/*
    This file is part of darktable,
    Copyright (C) 2011-2021 darktable developers.

    darktable is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    darktable is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with darktable.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "common/atomic.h"
#include "common/database.h"
#include "common/darktable.h"
#include "common/datetime.h"
#include "common/debug.h"
#include "common/file_location.h"
#include "common/iop_order.h"
#include "common/styles.h"
#include "common/history.h"
#ifdef HAVE_ICU
#include "common/sqliteicu.h"
#endif
#include "control/conf.h"
#include "control/control.h"
#include "gui/legacy_presets.h"

#include <gio/gio.h>
#include <glib.h>
#include <glib/gstdio.h>
#include <sqlite3.h>

#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/types.h>

// whenever _create_*_schema() gets changed you HAVE to bump this version and add an update path to
// _upgrade_*_schema_step()!
#define CURRENT_DATABASE_VERSION_LIBRARY 36
#define CURRENT_DATABASE_VERSION_DATA     9

// #define USE_NESTED_TRANSACTIONS
#define MAX_NESTED_TRANSACTIONS 0
/* transaction id */
static dt_atomic_int _trxid;

typedef struct dt_database_t
{
  gboolean lock_acquired;

  /* data database filename */
  gchar *dbfilename_data, *lockfile_data;

  /* library database filename */
  gchar *dbfilename_library, *lockfile_library;

  /* ondisk DB */
  sqlite3 *handle;

  gchar *error_message, *error_dbfilename;
  int error_other_pid;
} dt_database_t;


/* migrates database from old place to new */
static void _database_migrate_to_xdg_structure();

/* delete old mipmaps files */
static void _database_delete_mipmaps_files();

#define _SQLITE3_EXEC(a, b, c, d, e)                                                                         \
  if(sqlite3_exec(a, b, c, d, e) != SQLITE_OK)                                                               \
  {                                                                                                          \
    all_ok = FALSE;                                                                                          \
    failing_query = b;                                                                                       \
    goto end;                                                                                                \
  }

/* migrate from the legacy db format (with the 'settings' blob) to the first version this system knows */
static gboolean _migrate_schema(dt_database_t *db, int version)
{
  gboolean all_ok = TRUE;
  const char *failing_query = NULL;
  sqlite3_stmt *stmt;
  sqlite3_stmt *innerstmt;

  if(version != 36) // if anyone shows up with an older db we can probably add extra code
    return FALSE;

  sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
  // clang-format off
  // remove stuff that is either no longer needed or that got renamed
  _SQLITE3_EXEC(db->handle, "DROP TABLE IF EXISTS main.lock", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE IF EXISTS main.settings", NULL, NULL, NULL); // yes, we do this in many
                                                                                     // places. because it's really
                                                                                     // important to not miss it in
                                                                                     // any code path.
  _SQLITE3_EXEC(db->handle, "DROP INDEX IF EXISTS main.group_id_index", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP INDEX IF EXISTS main.imgid_index", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE IF EXISTS main.mipmaps", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE IF EXISTS main.mipmap_timestamps", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE IF EXISTS main.dt_migration_table", NULL, NULL, NULL);

  // using _create_library_schema() and filling that with the old data doesn't work since we always want to generate
  // version 1 tables
  ////////////////////////////// db_info
  _SQLITE3_EXEC(db->handle, "CREATE TABLE main.db_info (key VARCHAR PRIMARY KEY, value VARCHAR)",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "INSERT OR REPLACE INTO main.db_info (key, value) VALUES ('version', 1)",
                NULL, NULL, NULL);
  ////////////////////////////// film_rolls
  _SQLITE3_EXEC(db->handle, "CREATE INDEX IF NOT EXISTS main.film_rolls_folder_index ON film_rolls (folder)",
                NULL, NULL, NULL);
  ////////////////////////////// images
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN orientation INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN focus_distance REAL", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN group_id INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN histogram BLOB", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN lightmap BLOB", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN longitude REAL", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN latitude REAL", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN color_matrix BLOB", NULL, NULL, NULL);
  // the colorspace as specified in some image types
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN colorspace INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN version INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.images ADD COLUMN max_version INTEGER", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.images SET orientation = -1 WHERE orientation IS NULL", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.images SET focus_distance = -1 WHERE focus_distance IS NULL",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.images SET group_id = id WHERE group_id IS NULL", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.images SET max_version = (SELECT COUNT(*)-1 FROM main.images i WHERE "
                            "i.filename = main.images.filename AND "
                            "i.film_id = main.images.film_id) WHERE max_version IS NULL",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(
      db->handle,
      "UPDATE main.images SET version = (SELECT COUNT(*) FROM main.images i "
      "WHERE i.filename = main.images.filename AND "
      "i.film_id = main.images.film_id AND i.id < main.images.id) WHERE version IS NULL",
      NULL, NULL, NULL);
  // make sure we have AUTOINCREMENT on imgid --> move the whole thing away and recreate the table :(
  _SQLITE3_EXEC(db->handle, "ALTER TABLE main.images RENAME TO dt_migration_table", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP INDEX IF EXISTS main.images_group_id_index", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP INDEX IF EXISTS main.images_film_id_index", NULL, NULL, NULL);
  _SQLITE3_EXEC(
      db->handle,
      "CREATE TABLE main.images (id INTEGER PRIMARY KEY AUTOINCREMENT, group_id INTEGER, film_id INTEGER, "
      "width INTEGER, height INTEGER, filename VARCHAR, maker VARCHAR, model VARCHAR, "
      "lens VARCHAR, exposure REAL, aperture REAL, iso REAL, focal_length REAL, "
      "focus_distance REAL, datetime_taken CHAR(20), flags INTEGER, "
      "output_width INTEGER, output_height INTEGER, crop REAL, "
      "raw_parameters INTEGER, raw_denoise_threshold REAL, "
      "raw_auto_bright_threshold REAL, raw_black INTEGER, raw_maximum INTEGER, "
      "caption VARCHAR, description VARCHAR, license VARCHAR, sha1sum CHAR(40), "
      "orientation INTEGER, histogram BLOB, lightmap BLOB, longitude REAL, "
      "latitude REAL, color_matrix BLOB, colorspace INTEGER, version INTEGER, max_version INTEGER)",
      NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE INDEX main.images_group_id_index ON images (group_id)", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE INDEX main.images_film_id_index ON images (film_id)", NULL, NULL, NULL);
  _SQLITE3_EXEC(
      db->handle,
      "INSERT INTO main.images (id, group_id, film_id, width, height, filename, maker, model, "
      "lens, exposure, aperture, iso, focal_length, focus_distance, datetime_taken, flags, "
      "output_width, output_height, crop, raw_parameters, raw_denoise_threshold, "
      "raw_auto_bright_threshold, raw_black, raw_maximum, caption, description, license, sha1sum, "
      "orientation, histogram, lightmap, longitude, latitude, color_matrix, colorspace, version, "
      "max_version) "
      "SELECT id, group_id, film_id, width, height, filename, maker, model, lens, exposure, aperture, iso, "
      "focal_length, focus_distance, datetime_taken, flags, output_width, output_height, crop, "
      "raw_parameters, raw_denoise_threshold, raw_auto_bright_threshold, raw_black, raw_maximum, "
      "caption, description, license, sha1sum, orientation, histogram, lightmap, longitude, "
      "latitude, color_matrix, colorspace, version, max_version FROM dt_migration_table",
      NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE dt_migration_table", NULL, NULL, NULL);
  ////////////////////////////// selected_images
  // selected_images should have a primary key. add it if it's missing:
  _SQLITE3_EXEC(db->handle, "CREATE TEMPORARY TABLE dt_migration_table (imgid INTEGER)", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "INSERT INTO dt_migration_table SELECT imgid FROM main.selected_images", NULL, NULL,
                NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE main.selected_images", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE TABLE main.selected_images (imgid INTEGER PRIMARY KEY)", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "INSERT OR IGNORE INTO main.selected_images SELECT imgid FROM dt_migration_table",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE dt_migration_table", NULL, NULL, NULL);
  ////////////////////////////// history
  sqlite3_exec(db->handle, "ALTER TABLE main.history ADD COLUMN blendop_params BLOB", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.history ADD COLUMN blendop_version INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.history ADD COLUMN multi_priority INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.history ADD COLUMN multi_name VARCHAR(256)", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE INDEX IF NOT EXISTS main.history_imgid_index ON history (imgid)", NULL, NULL,
                NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.history SET blendop_version = 1 WHERE blendop_version IS NULL", NULL,
                NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.history SET multi_priority = 0 WHERE multi_priority IS NULL", NULL, NULL,
                NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.history SET multi_name = ' ' WHERE multi_name IS NULL", NULL, NULL, NULL);
  ////////////////////////////// mask
  _SQLITE3_EXEC(db->handle, "CREATE TABLE IF NOT EXISTS main.mask (imgid INTEGER, formid INTEGER, form INTEGER, "
                            "name VARCHAR(256), version INTEGER, "
                            "points BLOB, points_count INTEGER, source BLOB)",
                NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.mask ADD COLUMN source BLOB", NULL, NULL,
               NULL); // in case the table was there already but missed that column
  ////////////////////////////// tagged_images
  _SQLITE3_EXEC(db->handle, "CREATE INDEX IF NOT EXISTS main.tagged_images_tagid_index ON tagged_images (tagid)",
                NULL, NULL, NULL);
  ////////////////////////////// styles
  _SQLITE3_EXEC(db->handle,
                "CREATE TABLE IF NOT EXISTS main.styles (id INTEGER, name VARCHAR, description VARCHAR)", NULL,
                NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.styles ADD COLUMN id INTEGER", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.styles SET id = rowid WHERE id IS NULL", NULL, NULL, NULL);
  ////////////////////////////// style_items
  _SQLITE3_EXEC(db->handle, "CREATE TABLE IF NOT EXISTS main.style_items (styleid INTEGER, num INTEGER, module "
                            "INTEGER, operation VARCHAR(256), op_params BLOB, "
                            "enabled INTEGER, blendop_params BLOB, blendop_version INTEGER, multi_priority "
                            "INTEGER, multi_name VARCHAR(256))",
                NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.style_items ADD COLUMN blendop_params BLOB", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.style_items ADD COLUMN blendop_version INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.style_items ADD COLUMN multi_priority INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.style_items ADD COLUMN multi_name VARCHAR(256)", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.style_items SET blendop_version = 1 WHERE blendop_version IS NULL", NULL,
                NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.style_items SET multi_priority = 0 WHERE multi_priority IS NULL", NULL,
                NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.style_items SET multi_name = ' ' WHERE multi_name IS NULL", NULL, NULL,
                NULL);
  ////////////////////////////// color_labels
  // color_labels could have a PRIMARY KEY that we don't want
  _SQLITE3_EXEC(db->handle, "CREATE TEMPORARY TABLE dt_migration_table (imgid INTEGER, color INTEGER)", NULL,
                NULL, NULL);
  _SQLITE3_EXEC(db->handle, "INSERT INTO dt_migration_table SELECT imgid, color FROM main.color_labels", NULL,
                NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE main.color_labels", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE TABLE main.color_labels (imgid INTEGER, color INTEGER)", NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE UNIQUE INDEX main.color_labels_idx ON color_labels (imgid, color)", NULL, NULL,
                NULL);
  _SQLITE3_EXEC(db->handle, "INSERT OR IGNORE INTO main.color_labels SELECT imgid, color FROM dt_migration_table",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "DROP TABLE dt_migration_table", NULL, NULL, NULL);
  ////////////////////////////// meta_data
  _SQLITE3_EXEC(db->handle, "CREATE TABLE IF NOT EXISTS main.meta_data (id INTEGER, key INTEGER, value VARCHAR)",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "CREATE INDEX IF NOT EXISTS main.metadata_index ON meta_data (id, key)", NULL, NULL,
                NULL);
  ////////////////////////////// presets
  _SQLITE3_EXEC(db->handle, "CREATE TABLE IF NOT EXISTS main.presets (name VARCHAR, description VARCHAR, "
                            "operation VARCHAR, op_version INTEGER, op_params BLOB, "
                            "enabled INTEGER, blendop_params BLOB, blendop_version INTEGER, multi_priority "
                            "INTEGER, multi_name VARCHAR(256), "
                            "model VARCHAR, maker VARCHAR, lens VARCHAR, iso_min REAL, iso_max REAL, "
                            "exposure_min REAL, exposure_max REAL, "
                            "aperture_min REAL, aperture_max REAL, focal_length_min REAL, focal_length_max "
                            "REAL, writeprotect INTEGER, "
                            "autoapply INTEGER, filter INTEGER, def INTEGER, isldr INTEGER)",
                NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.presets ADD COLUMN op_version INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.presets ADD COLUMN blendop_params BLOB", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.presets ADD COLUMN blendop_version INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.presets ADD COLUMN multi_priority INTEGER", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "ALTER TABLE main.presets ADD COLUMN multi_name VARCHAR(256)", NULL, NULL, NULL);
  // the unique index only works if the db doesn't have any (name, operation, op_version) more than once.
  // apparently there are dbs out there which do have that. :(
  sqlite3_prepare_v2(db->handle,
                     "SELECT p.rowid, p.name, p.operation, p.op_version FROM main.presets p INNER JOIN "
                     "(SELECT * FROM (SELECT rowid, name, operation, op_version, COUNT(*) AS count "
                     "FROM main.presets GROUP BY name, operation, op_version) WHERE count > 1) s "
                     "ON p.name = s.name AND p.operation = s.operation AND p.op_version = s.op_version",
                     -1, &stmt, NULL);
  // clang-format on
  char *last_name = NULL, *last_operation = NULL;
  int last_op_version = 0;
  int i = 0;
  while(sqlite3_step(stmt) == SQLITE_ROW)
  {
    const int rowid = sqlite3_column_int(stmt, 0);
    const char *name = (const char *)sqlite3_column_text(stmt, 1);
    const char *operation = (const char *)sqlite3_column_text(stmt, 2);
    const int op_version = sqlite3_column_int(stmt, 3);

    // is it still the same (name, operation, op_version) triple?
    if(!last_name || strcmp(last_name, name) || !last_operation || strcmp(last_operation, operation)
       || last_op_version != op_version)
    {
      g_free(last_name);
      g_free(last_operation);
      last_name = g_strdup(name);
      last_operation = g_strdup(operation);
      last_op_version = op_version;
      i = 0;
    }

    // find the next free amended version of name
    // clang-format off
    sqlite3_prepare_v2(db->handle, "SELECT name FROM main.presets  WHERE name = ?1 || ' (' || ?2 || ')' AND "
                                   "operation = ?3 AND op_version = ?4",
                       -1, &innerstmt, NULL);
    // clang-format on
    while(1)
    {
      sqlite3_bind_text(innerstmt, 1, name, -1, SQLITE_TRANSIENT);
      sqlite3_bind_int(innerstmt, 2, i);
      sqlite3_bind_text(innerstmt, 3, operation, -1, SQLITE_TRANSIENT);
      sqlite3_bind_int(innerstmt, 4, op_version);
      if(sqlite3_step(innerstmt) != SQLITE_ROW) break;
      sqlite3_reset(innerstmt);
      sqlite3_clear_bindings(innerstmt);
      i++;
    }
    sqlite3_finalize(innerstmt);

    // rename preset
    // clang-format off
    const char *query = "UPDATE main.presets SET name = name || ' (' || ?1 || ')' WHERE rowid = ?2";
    // clang-format on
    sqlite3_prepare_v2(db->handle, query, -1, &innerstmt, NULL);
    sqlite3_bind_int(innerstmt, 1, i);
    sqlite3_bind_int(innerstmt, 2, rowid);
    if(sqlite3_step(innerstmt) != SQLITE_DONE)
    {
      all_ok = FALSE;
      failing_query = query;
      goto end;
    }
    sqlite3_finalize(innerstmt);
  }
  sqlite3_finalize(stmt);
  g_free(last_name);
  g_free(last_operation);
  // now we should be able to create the index
  // clang-format off
  _SQLITE3_EXEC(db->handle,
                "CREATE UNIQUE INDEX IF NOT EXISTS main.presets_idx ON presets (name, operation, op_version)",
                NULL, NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.presets SET blendop_version = 1 WHERE blendop_version IS NULL", NULL,
                NULL, NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.presets SET multi_priority = 0 WHERE multi_priority IS NULL", NULL, NULL,
                NULL);
  _SQLITE3_EXEC(db->handle, "UPDATE main.presets SET multi_name = ' ' WHERE multi_name IS NULL", NULL, NULL, NULL);
  // clang-format on


  // There are systems where absolute paths don't start with '/' (like Windows).
  // Since the bug which introduced absolute paths to the db was fixed before a
  // Windows build was available this shouldn't matter though.
  // clang-format off
  sqlite3_prepare_v2(db->handle, "SELECT id, filename FROM main.images WHERE filename LIKE '/%'", -1, &stmt, NULL);
  sqlite3_prepare_v2(db->handle, "UPDATE main.images SET filename = ?1 WHERE id = ?2", -1, &innerstmt, NULL);
  // clang-format on
  while(sqlite3_step(stmt) == SQLITE_ROW)
  {
    const int id = sqlite3_column_int(stmt, 0);
    const char *path = (const char *)sqlite3_column_text(stmt, 1);
    gchar *filename = g_path_get_basename(path);
    sqlite3_bind_text(innerstmt, 1, filename, -1, SQLITE_TRANSIENT);
    sqlite3_bind_int(innerstmt, 2, id);
    sqlite3_step(innerstmt);
    sqlite3_reset(innerstmt);
    sqlite3_clear_bindings(innerstmt);
    g_free(filename);
  }
  sqlite3_finalize(stmt);
  sqlite3_finalize(innerstmt);

  // We used to insert datetime_taken entries with '-' as date separators. Since that doesn't work well with
  // the regular ':' when parsing
  // or sorting we changed it to ':'. This takes care to change what we have as leftovers
  // clang-format off
  _SQLITE3_EXEC(
      db->handle,
      "UPDATE main.images SET datetime_taken = REPLACE(datetime_taken, '-', ':') WHERE datetime_taken LIKE '%-%'",
      NULL, NULL, NULL);
  // clang-format on

end:
  if(all_ok)
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
  else
  {
    fprintf(stderr, "[init] failing query: `%s'\n", failing_query);
    fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));
    sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);
  }

  return all_ok;
}

#undef _SQLITE3_EXEC

#define TRY_EXEC(_query, _message)                                               \
  do                                                                             \
  {                                                                              \
    if(sqlite3_exec(db->handle, _query, NULL, NULL, NULL) != SQLITE_OK)          \
    {                                                                            \
      fprintf(stderr, _message);                                                 \
      fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));              \
      FINALIZE;                                                                  \
      sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);        \
      return version;                                                            \
    }                                                                            \
  } while(0)

#define TRY_STEP(_stmt, _expected, _message)                                     \
  do                                                                             \
  {                                                                              \
    if(sqlite3_step(_stmt) != _expected)                                         \
    {                                                                            \
      fprintf(stderr, _message);                                                 \
      fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));              \
      FINALIZE;                                                                  \
      sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);        \
      return version;                                                            \
    }                                                                            \
  } while(0)

#define TRY_PREPARE(_stmt, _query, _message)                                     \
  do                                                                             \
  {                                                                              \
    if(sqlite3_prepare_v2(db->handle, _query, -1, &_stmt, NULL) != SQLITE_OK)    \
    {                                                                            \
      fprintf(stderr, _message);                                                 \
      fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));              \
      FINALIZE;                                                                  \
      sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);        \
      return version;                                                            \
    }                                                                            \
  } while(0)

// redefine this where needed
#define FINALIZE

/* do the real migration steps, returns the version the db was converted to */
static int _upgrade_library_schema_step(dt_database_t *db, int version)
{
  sqlite3_stmt *stmt;
  int new_version = version;
  if(version == CURRENT_DATABASE_VERSION_LIBRARY)
    return version;
  else if(version == 0)
  {
    // this can't happen, we started with 1, but it's a good example how this function works
    // <do some magic to the db>
    new_version = 1; // the version we transformed the db to. this way it might be possible to roll back or
                     // add fast paths
  }
  else if(version == 1)
  {
    // 1 -> 2 added write_timestamp
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN write_timestamp INTEGER",
             "[init] can't add `write_timestamp' column to database\n");
    TRY_EXEC("UPDATE main.images SET write_timestamp = STRFTIME('%s', 'now') WHERE write_timestamp IS NULL",
             "[init] can't initialize `write_timestamp' with current point in time\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 2;
  }
  else if(version == 2)
  {
    // 2 -> 3 reset raw_black and raw_maximum. in theory we should change the columns from REAL to INTEGER,
    // but sqlite doesn't care about types so whatever
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("UPDATE main.images SET raw_black = 0, raw_maximum = 16384",
             "[init] can't reset raw_black and raw_maximum\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 3;
  }
  else if(version == 3)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("CREATE TRIGGER insert_tag AFTER INSERT ON main.tags"
             " BEGIN"
             "   INSERT INTO tagxtag SELECT id, new.id, 0 FROM TAGS;"
             "   UPDATE tagxtag SET count = 1000000 WHERE id1=new.id AND id2=new.id;"
             " END",
             "[init] can't create insert_tag trigger\n");
    TRY_EXEC("CREATE TRIGGER delete_tag BEFORE DELETE ON main.tags"
             " BEGIN"
             "   DELETE FROM tagxtag WHERE id1=old.id OR id2=old.id;"
             "   DELETE FROM tagged_images WHERE tagid=old.id;"
             " END",
             "[init] can't create delete_tag trigger\n");
    TRY_EXEC("CREATE TRIGGER attach_tag AFTER INSERT ON main.tagged_images"
             " BEGIN"
             "   UPDATE tagxtag"
             "     SET count = count + 1"
             "     WHERE (id1=new.tagid AND id2 IN (SELECT tagid FROM tagged_images WHERE imgid=new.imgid))"
             "        OR (id2=new.tagid AND id1 IN (SELECT tagid FROM tagged_images WHERE imgid=new.imgid));"
             " END",
             "[init] can't create attach_tag trigger\n");
    TRY_EXEC("CREATE TRIGGER detach_tag BEFORE DELETE ON main.tagged_images"
             " BEGIN"
             "   UPDATE tagxtag"
             "     SET count = count - 1"
             "     WHERE (id1=old.tagid AND id2 IN (SELECT tagid FROM tagged_images WHERE imgid=old.imgid))"
             "        OR (id2=old.tagid AND id1 IN (SELECT tagid FROM tagged_images WHERE imgid=old.imgid));"
             " END",
             "[init] can't create detach_tag trigger\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 4;
  }
  else if(version == 4)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("ALTER TABLE main.presets RENAME TO tmp_presets",  "[init] can't rename table presets\n");

    TRY_EXEC("CREATE TABLE main.presets (name VARCHAR, description VARCHAR, operation VARCHAR, op_params BLOB,"
             "enabled INTEGER, blendop_params BLOB, model VARCHAR, maker VARCHAR, lens VARCHAR,"
             "iso_min REAL, iso_max REAL, exposure_min REAL, exposure_max REAL, aperture_min REAL,"
             "aperture_max REAL, focal_length_min REAL, focal_length_max REAL, writeprotect INTEGER,"
             "autoapply INTEGER, filter INTEGER, def INTEGER, format INTEGER, op_version INTEGER,"
             "blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
             "[init] can't create new presets table\n");

    TRY_EXEC("INSERT INTO main.presets (name, description, operation, op_params, enabled, blendop_params, model, "
             "maker, lens, iso_min, iso_max, exposure_min, exposure_max, aperture_min, aperture_max,"
             "focal_length_min, focal_length_max, writeprotect, autoapply, filter, def, format, op_version, "
             "blendop_version, multi_priority, multi_name) SELECT name, description, operation, op_params, "
             "enabled, blendop_params, model, maker, lens, iso_min, iso_max, exposure_min, exposure_max, "
             "aperture_min, aperture_max, focal_length_min, focal_length_max, writeprotect, autoapply, filter, "
             "def, isldr, op_version, blendop_version, multi_priority, multi_name FROM tmp_presets",
             "[init] can't populate presets table from tmp_presets\n");

    TRY_EXEC("DROP TABLE tmp_presets", "[init] can't delete table tmp_presets\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 5;
  }
  else if(version == 5)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("CREATE INDEX main.images_filename_index ON images (filename)",
             "[init] can't create index on image filename\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 6;
  }
  else if(version == 6)
  {
    // some ancient tables can have the styleid column of style_items be called style_id. fix that.
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);

    if(sqlite3_exec(db->handle, "SELECT style_id FROM main.style_items", NULL, NULL, NULL) == SQLITE_OK)
    {
      // clang-format off
      TRY_EXEC("ALTER TABLE main.style_items RENAME TO tmp_style_items",
               "[init] can't rename table style_items\n");

      TRY_EXEC("CREATE TABLE main.style_items (styleid INTEGER, num INTEGER, module INTEGER, "
               "operation VARCHAR(256), op_params BLOB, enabled INTEGER, "
               "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
               "[init] can't create new style_items table\n");

      TRY_EXEC("INSERT INTO main.style_items (styleid, num, module, operation, op_params, enabled,"
               "                         blendop_params, blendop_version, multi_priority, multi_name)"
               "                  SELECT style_id, num, module, operation, op_params, enabled,"
               "                         blendop_params, blendop_version, multi_priority, multi_name"
               "                  FROM   tmp_style_items",
               "[init] can't populate style_items table from tmp_style_items\n");

      TRY_EXEC("DROP TABLE tmp_style_items", "[init] can't delete table tmp_style_items\n");
      // clang-format on
    }

    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 7;
  }
  else if(version == 7)
  {
    // make sure that we have no film rolls with a NULL folder
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("ALTER TABLE main.film_rolls RENAME TO tmp_film_rolls", "[init] can't rename table film_rolls\n");

    TRY_EXEC("CREATE TABLE main.film_rolls "
             "(id INTEGER PRIMARY KEY, datetime_accessed CHAR(20), "
             "folder VARCHAR(1024) NOT NULL)",
             "[init] can't create new film_rolls table\n");

    TRY_EXEC("INSERT INTO main.film_rolls (id, datetime_accessed, folder) "
             "SELECT id, datetime_accessed, folder "
             "FROM   tmp_film_rolls "
             "WHERE  folder IS NOT NULL",
             "[init] can't populate film_rolls table from tmp_film_rolls\n");

    TRY_EXEC("DROP TABLE tmp_film_rolls", "[init] can't delete table tmp_film_rolls\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 8;
  }
  else if(version == 8)
  {
    // 8 -> 9 added history_end column to images
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN history_end INTEGER",
             "[init] can't add `history_end' column to database\n");

    TRY_EXEC("UPDATE main.images SET history_end = (SELECT IFNULL(MAX(num) + 1, 0) FROM main.history "
             "WHERE imgid = id)", "[init] can't initialize `history_end' with last history entry\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 9;
  }
  else if(version == 9)
  {
    // 9 -> 10 cleanup of last update :(
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("UPDATE main.images SET history_end = (SELECT IFNULL(MAX(num) + 1, 0) FROM main.history "
             "WHERE imgid = id)", "[init] can't set `history_end' to 0 where it was NULL\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 10;
  }
  else if(version == 10)
  {
    // 10 -> 11 added altitude column to images
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN altitude REAL",
             "[init] can't add `altitude' column to database\n");

    TRY_EXEC("UPDATE main.images SET altitude = NULL", "[init] can't initialize `altitude' with NULL\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 11;
  }
  else if(version == 11)
  {
    // 11 -> 12 tagxtag was removed in order to reduce database size
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("DROP TRIGGER main.detach_tag", "[init] can't drop trigger `detach_tag' from database\n");

    TRY_EXEC("DROP TRIGGER main.attach_tag", "[init] can't drop trigger `attach_tag' from database\n");

    TRY_EXEC("DROP TRIGGER main.delete_tag", "[init] can't drop trigger `delete_tag' from database\n");

    TRY_EXEC("DROP TRIGGER main.insert_tag", "[init] can't drop trigger `insert_tag' from database\n");

    TRY_EXEC("DROP TABLE main.tagxtag", "[init] can't drop table `tagxtag' from database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 12;
  }
  else if(version == 12)
  {
    // 11 -> 12 move presets, styles and tags over to the data database
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);

    ////////////// presets
#undef FINALIZE
#define FINALIZE                                                                   \
    do                                                                             \
    {                                                                              \
      sqlite3_finalize(stmt);                                                      \
      sqlite3_finalize(select_stmt);                                               \
      sqlite3_finalize(count_clashes_stmt);                                        \
      sqlite3_finalize(update_name_stmt);                                          \
      sqlite3_finalize(insert_stmt);                                               \
      sqlite3_finalize(delete_stmt);                                               \
    } while(0)

    stmt = NULL;
    sqlite3_stmt *insert_stmt = NULL, *delete_stmt = NULL, *select_stmt = NULL, *count_clashes_stmt = NULL,
    *update_name_stmt = NULL;
    // clang-format off
    // remove presets that are already in data.
    // we can't use a NATURAL JOIN here as that fails when columns have NULL values. :-(
    TRY_EXEC("DELETE FROM main.presets WHERE rowid IN (SELECT p1.rowid FROM main.presets p1 "
             "JOIN data.presets p2 ON "
                 "p1.name IS p2.name AND "
                 "p1.description IS p2.description AND "
                 "p1.operation IS p2.operation AND "
                 "p1.op_version IS p2.op_version AND "
                 "p1.op_params IS p2.op_params AND "
                 "p1.enabled IS p2.enabled AND "
                 "p1.blendop_params IS p2.blendop_params AND "
                 "p1.blendop_version IS p2.blendop_version AND "
                 "p1.multi_priority IS p2.multi_priority AND "
                 "p1.multi_name IS p2.multi_name AND "
                 "p1.model IS p2.model AND "
                 "p1.maker IS p2.maker AND "
                 "p1.lens IS p2.lens AND "
                 "p1.iso_min IS p2.iso_min AND "
                 "p1.iso_max IS p2.iso_max AND "
                 "p1.exposure_min IS p2.exposure_min AND "
                 "p1.exposure_max IS p2.exposure_max AND "
                 "p1.aperture_min IS p2.aperture_min AND "
                 "p1.aperture_max IS p2.aperture_max AND "
                 "p1.focal_length_min IS p2.focal_length_min AND "
                 "p1.focal_length_max IS p2.focal_length_max AND "
                 "p1.writeprotect IS p2.writeprotect AND "
                 "p1.autoapply IS p2.autoapply AND "
                 "p1.filter IS p2.filter AND "
                 "p1.def IS p2.def AND "
                 "p1.format IS p2.format "
             "WHERE p1.writeprotect = 0)",
             "[init] can't delete already migrated presets from database\n");

    // find all presets that are clashing with something else in presets. that can happen as we introduced an
    // index on presets in data which wasn't in place in library.
    TRY_PREPARE(select_stmt, "SELECT p.rowid, r FROM main.presets AS p, (SELECT rowid AS r, name, operation, "
                             "op_version FROM main.presets GROUP BY name, operation, op_version HAVING "
                             "COUNT(*) > 1) USING (name, operation, op_version) WHERE p.rowid != r",
                "[init] can't prepare selecting presets with same name, operation, op_version from database\n");

    // see if an updated preset name still causes problems
    TRY_PREPARE(count_clashes_stmt, "SELECT COUNT(*) FROM main.presets AS p, (SELECT name, operation, op_version "
                                    "FROM main.presets WHERE rowid = ?1) AS i ON p.name = i.name || \" #\" || ?2 "
                                    "AND p.operation = i.operation AND p.op_version = i.op_version",
                "[init] can't prepare selection of preset count by name from database\n");

    // update the preset name for good
    TRY_PREPARE(update_name_stmt, "UPDATE main.presets SET name = name || \" #\" || ?1 WHERE rowid = ?2",
                "[init] can't prepare updating of preset name in database\n");

    // find all presets that would be clashing with something in data
    TRY_PREPARE(stmt, "SELECT p1.rowid FROM main.presets p1 INNER JOIN data.presets p2 "
                      "USING (name, operation, op_version) WHERE p1.writeprotect = 0",
                "[init] can't access table `presets' in database\n");

    // ... and move them over with a new name
    TRY_PREPARE(insert_stmt, "INSERT OR FAIL INTO data.presets (name, description, operation, op_version, "
                             "op_params, enabled, blendop_params, blendop_version, multi_priority, multi_name, "
                             "model, maker, lens, iso_min, iso_max, exposure_min, exposure_max, aperture_min, "
                             "aperture_max, focal_length_min, focal_length_max, writeprotect, autoapply, filter, "
                             "def, format) "
                             "SELECT name || \" #\" || ?1, description, operation, op_version, op_params, "
                             "enabled, blendop_params, blendop_version, multi_priority, multi_name, model, maker, "
                             "lens, iso_min, iso_max, exposure_min, exposure_max, aperture_min, aperture_max, "
                             "focal_length_min, focal_length_max, writeprotect, autoapply, filter, def, format "
                             "FROM main.presets p1 WHERE p1.rowid = ?2",
                "[init] can't prepare insertion statement\n");

    TRY_PREPARE(delete_stmt, "DELETE FROM main.presets WHERE rowid = ?1", "[init] can't prepare deletion statement\n");
    // clang-format on
    // first rename presets with (name, operation, op_version) not being unique
    while(sqlite3_step(select_stmt) == SQLITE_ROW)
    {
      const int own_rowid = sqlite3_column_int(select_stmt, 0);
      const int other_rowid = sqlite3_column_int(select_stmt, 1);
      int preset_version = 0;

      do
      {
        preset_version++;
        sqlite3_reset(count_clashes_stmt);
        sqlite3_clear_bindings(count_clashes_stmt);
        sqlite3_bind_int(count_clashes_stmt, 1, other_rowid);
        sqlite3_bind_int(count_clashes_stmt, 2, preset_version);
      }
      while(sqlite3_step(count_clashes_stmt) == SQLITE_ROW && sqlite3_column_int(count_clashes_stmt, 0) > 0);

      sqlite3_bind_int(update_name_stmt, 1, preset_version);
      sqlite3_bind_int(update_name_stmt, 2, own_rowid);
      TRY_STEP(update_name_stmt, SQLITE_DONE, "[init] can't rename preset in database\n");
      sqlite3_reset(update_name_stmt);
      sqlite3_reset(update_name_stmt);
    }

    // now rename to avoid clashes with data.presets
    while(sqlite3_step(stmt) == SQLITE_ROW)
    {
      int preset_version = 0;
      const int rowid = sqlite3_column_int(stmt, 0);

      do
      {
        preset_version++;
        sqlite3_reset(insert_stmt);
        sqlite3_clear_bindings(insert_stmt);
        sqlite3_bind_int(insert_stmt, 1, preset_version);
        sqlite3_bind_int(insert_stmt, 2, rowid);
      } while(sqlite3_step(insert_stmt) != SQLITE_DONE);

      sqlite3_reset(delete_stmt);
      sqlite3_clear_bindings(delete_stmt);
      sqlite3_bind_int(delete_stmt, 1, rowid);
      TRY_STEP(delete_stmt, SQLITE_DONE, "[init] can't delete preset from database\n");
    }
    // clang-format off
    // all that is left in presets should be those that can be moved over without any further concerns
    TRY_EXEC("INSERT OR FAIL INTO data.presets SELECT name, description, operation, "
             "op_version, op_params, enabled, blendop_params, blendop_version, "
             "multi_priority, multi_name, model, maker, lens, iso_min, iso_max, "
             "exposure_min, exposure_max, aperture_min, aperture_max, "
             "focal_length_min, focal_length_max, writeprotect, autoapply, filter, "
             "def, format FROM main.presets WHERE writeprotect = 0",
             "[init] can't copy presets to the data database\n");
    // ... delete them on the old side
    TRY_EXEC("DELETE FROM main.presets WHERE writeprotect = 0",
             "[init] can't copy presets to the data database\n");
    // clang-format on

    FINALIZE;
#undef FINALIZE

    ////////////// styles
#define FINALIZE                                                                   \
    do                                                                             \
    {                                                                              \
      sqlite3_finalize(stmt);                                                      \
      sqlite3_finalize(insert_stmt);                                               \
      sqlite3_finalize(select_stmt);                                               \
      sqlite3_finalize(delete_stmt);                                               \
      sqlite3_finalize(update_name_stmt);                                          \
      sqlite3_finalize(select_new_stmt);                                           \
      sqlite3_finalize(copy_style_items_stmt);                                     \
      sqlite3_finalize(delete_style_items_stmt);                                   \
    } while(0)

    stmt = NULL;
    select_stmt = NULL;
    update_name_stmt = NULL;
    insert_stmt = NULL;
    delete_stmt = NULL;
    sqlite3_stmt *select_new_stmt = NULL, *copy_style_items_stmt = NULL, *delete_style_items_stmt = NULL;
    // clang-format off
    TRY_PREPARE(stmt, "SELECT id, name FROM main.styles", "[init] can't prepare style selection from database\n");
    TRY_PREPARE(select_stmt, "SELECT rowid FROM data.styles WHERE name = ?1 LIMIT 1",
                "[init] can't prepare style item selection from database\n");
    TRY_PREPARE(update_name_stmt, "UPDATE main.styles SET name = ?1 WHERE id = ?2",
                "[init] can't prepare style name update\n");
    TRY_PREPARE(insert_stmt, "INSERT INTO data.styles (id, name, description) "
                             "SELECT (SELECT COALESCE(MAX(id),0)+1 FROM data.styles), name, description "
                             "FROM main.styles where id = ?1",
                "[init] can't prepare style insertion for database\n");
    TRY_PREPARE(delete_stmt, "DELETE FROM main.styles WHERE id = ?1",
                "[init] can't prepare style deletion for database\n");
    TRY_PREPARE(select_new_stmt, "SELECT id FROM data.styles WHERE rowid = ?1",
                "[init] can't prepare style selection from data database\n");
    TRY_PREPARE(copy_style_items_stmt, "INSERT INTO data.style_items "
                                       "(styleid, num, module, operation, op_params, enabled, blendop_params, "
                                       "blendop_version, multi_priority, multi_name) "
                                       "SELECT ?1, num, module, operation, op_params, enabled, blendop_params, "
                                       "blendop_version, multi_priority, multi_name FROM main.style_items "
                                       "WHERE styleid = ?2",
                "[init] can't prepare style item copy into data database\n");
    TRY_PREPARE(delete_style_items_stmt, "DELETE FROM main.style_items WHERE styleid = ?1",
                "[init] can't prepare style item deletion for database\n");
    // clang-format on
    while(sqlite3_step(stmt) == SQLITE_ROW)
    {
      const int id = sqlite3_column_int(stmt, 0);
      const char *name = (const char *)sqlite3_column_text(stmt, 1);

      // find a unique name of the style for data.styles
      sqlite3_bind_text(select_stmt, 1, name, -1, SQLITE_TRANSIENT);
      if(sqlite3_step(select_stmt) == SQLITE_ROW)
      {
        // we need to append a version
        int style_version = 0;
        char *new_name = NULL;
        do
        {
          style_version++;
          g_free(new_name);
          new_name = g_strdup_printf("%s #%d", name, style_version);
          sqlite3_reset(select_stmt);
          sqlite3_clear_bindings(select_stmt);
          sqlite3_bind_text(select_stmt, 1, new_name, -1, SQLITE_TRANSIENT);
        } while(sqlite3_step(select_stmt) == SQLITE_ROW);

        // update the name in the old place
        sqlite3_bind_text(update_name_stmt, 1, new_name, -1, SQLITE_TRANSIENT);
        sqlite3_bind_int(update_name_stmt, 2, id);
        TRY_STEP(update_name_stmt, SQLITE_DONE, "[init] can't update name of style in database\n");
        sqlite3_reset(update_name_stmt);
        sqlite3_clear_bindings(update_name_stmt);
        g_free(new_name);
      }

      // move the style to data.styles and get the rowid
      sqlite3_bind_int(insert_stmt, 1, id);
      TRY_STEP(insert_stmt, SQLITE_DONE, "[init] can't insert style into data database\n");
      sqlite3_int64 last_rowid = sqlite3_last_insert_rowid(db->handle);

      // delete style from styles
      sqlite3_bind_int(delete_stmt, 1, id);
      TRY_STEP(delete_stmt, SQLITE_DONE, "[init] can't delete style from database\n");

      sqlite3_bind_int(select_new_stmt, 1, last_rowid);
      TRY_STEP(select_new_stmt, SQLITE_ROW, "[init] can't select new style from data database\n");
      const int new_id = sqlite3_column_int(select_new_stmt, 0);

      // now that we have the style over in data.styles and the new id we can just copy over all style items
      sqlite3_bind_int(copy_style_items_stmt, 1, new_id);
      sqlite3_bind_int(copy_style_items_stmt, 2, id);
      TRY_STEP(copy_style_items_stmt, SQLITE_DONE, "[init] can't copy style items into data database\n");

      // delete the style items from the old table
      sqlite3_bind_int(delete_style_items_stmt, 1, id);
      TRY_STEP(delete_style_items_stmt, SQLITE_DONE, "[init] can't delete style items from database\n");

      // cleanup for the next round
      sqlite3_reset(insert_stmt);
      sqlite3_clear_bindings(insert_stmt);
      sqlite3_reset(select_stmt);
      sqlite3_clear_bindings(select_stmt);
      sqlite3_reset(delete_stmt);
      sqlite3_clear_bindings(delete_stmt);
      sqlite3_reset(select_new_stmt);
      sqlite3_clear_bindings(select_new_stmt);
      sqlite3_reset(copy_style_items_stmt);
      sqlite3_clear_bindings(copy_style_items_stmt);
      sqlite3_reset(delete_style_items_stmt);
      sqlite3_clear_bindings(delete_style_items_stmt);
    }
    FINALIZE;
#undef FINALIZE

    ////////////// tags
#define FINALIZE
    // clang-format off
    // tags
    TRY_EXEC("INSERT OR IGNORE INTO data.tags (name, icon, description, flags) "
             "SELECT name, icon, description, flags FROM main.tags",
             "[init] can't prepare insertion of used tags into data database\n");

    // tagged images
    // we need a temp table to update tagged_images due to its primary key
    TRY_EXEC("CREATE TEMPORARY TABLE tagged_images_tmp (imgid INTEGER, tagid INTEGER)",
             "[init] can't create temporary table for updating `tagged_images'\n");

    TRY_EXEC("INSERT INTO tagged_images_tmp (imgid, tagid) "
             "SELECT imgid, (SELECT t2.id FROM main.tags t1, data.tags t2 USING (name) WHERE t1.id = tagid) "
             "FROM main.tagged_images", "[init] can't insert into `tagged_images_tmp'\n");

    TRY_EXEC("DELETE FROM main.tagged_images", "[init] can't delete tagged images in database\n");

    TRY_EXEC("INSERT OR IGNORE INTO main.tagged_images (imgid, tagid) SELECT imgid, tagid FROM tagged_images_tmp",
             "[init] can't copy updated values back to `tagged_images'\n");

    TRY_EXEC("DROP TABLE tagged_images_tmp", "[init] can't drop table `tagged_images_tmp' from database\n");

    ////////////// cleanup - drop the indexes and tags
    TRY_EXEC("DROP INDEX IF EXISTS main.presets_idx", "[init] can't drop index `presets_idx' from database\n");
    TRY_EXEC("DROP TABLE main.presets", "[init] can't drop table `presets' from database\n");
    TRY_EXEC("DROP TABLE main.style_items", "[init] can't drop table `style_items' from database\n");
    TRY_EXEC("DROP TABLE main.styles", "[init] can't drop table `styles' from database\n");
    TRY_EXEC("DROP TABLE main.tags", "[init] can't drop table `tags' from database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 13;
  } else if(version == 13)
  {
    // 12 -> 13 bring back the used tag names to library.db so people can use it independently of data.db
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("CREATE TABLE main.used_tags (id INTEGER, name VARCHAR NOT NULL)",
             "[init] can't create `used_tags` table\n");

    TRY_EXEC("CREATE INDEX main.used_tags_idx ON used_tags (id, name)",
             "[init] can't create index on table `used_tags' in database\n");

    TRY_EXEC("INSERT INTO main.used_tags (id, name) SELECT t.id, t.name FROM data.tags AS t, main.tagged_images "
             "AS i ON t.id = i.tagid GROUP BY t.id",
             "[init] can't insert used tags into `used_tags` table in database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 14;
  }
  else if(version == 14)
  {
    // 13 -> fix the index on used_tags to be a UNIQUE index :-/
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("DELETE FROM main.used_tags WHERE rowid NOT IN (SELECT rowid FROM used_tags GROUP BY id)",
             "[init] can't delete duplicated entries from `used_tags' in database\n");

    TRY_EXEC("DROP INDEX main.used_tags_idx", "[init] can't drop index `used_tags_idx' from database\n");

    TRY_EXEC("CREATE UNIQUE INDEX main.used_tags_idx ON used_tags (id, name)",
             "[init] can't create index `used_tags_idx' in database\n");

    TRY_EXEC("DELETE FROM main.tagged_images WHERE tagid IS NULL",
             "[init] can't delete NULL entries from `tagged_images' in database");

    TRY_EXEC("DELETE FROM main.used_tags WHERE id NOT IN (SELECT DISTINCT tagid FROM main.tagged_images)",
             "[init] can't delete unused tags from `used_tags' in database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 15;
  }
  else if(version == 15)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    ////////////////////////////// custom image order
    // clang-format off
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN position INTEGER",
             "[init] can't add `position' column to images table in database\n");
    TRY_EXEC("CREATE INDEX main.image_position_index ON images (position)",
             "[init] can't create index for custom image order table\n");

    // Set the initial image sequence. The image id - the sequence images were imported -
    // defines the initial order of images.
    //
    // An int64 is used for the position index. The upper 31 bits define the initial order.
    // The lower 32bit provide space to reorder images.
    //
    // see: dt_collection_move_before()
    //
    TRY_EXEC("UPDATE main.images SET position = id << 32",
             "[init] can't update positions custom image order table\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 16;
  }
  else if(version == 16)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    ////////////////////////////// final image aspect ratio
    // clang-format off
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN aspect_ratio REAL",
             "[init] can't add `aspect_ratio' column to images table in database\n");
    TRY_EXEC("UPDATE main.images SET aspect_ratio = 0.0",
             "[init] can't update aspect_ratio in database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 17;
  }
  else if(version == 17)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);

    ////////////////////////////// masks history
    // clang-format off
    TRY_EXEC("CREATE TABLE main.masks_history (imgid INTEGER, num INTEGER, formid INTEGER, form INTEGER, name VARCHAR(256), "
             "version INTEGER, points BLOB, points_count INTEGER, source BLOB)",
             "[init] can't create `masks_history` table\n");

    TRY_EXEC("CREATE INDEX main.masks_history_imgid_index ON masks_history (imgid)",
             "[init] can't create index `masks_history_imgid_index' in database\n");

    // to speed up the mask look-up, and makes the following UPDATE instantaneous whereas it could takes hours
    TRY_EXEC("CREATE INDEX main.mask_imgid_index ON mask (imgid);",
             "[init] can't create index `mask_imgid_index' in database\n");

    // create a mask manager entry on history for all images containing all forms
    // make room for mask manager history entry
    TRY_EXEC("UPDATE main.history SET num=num+1 WHERE imgid IN (SELECT imgid FROM main.mask WHERE main.mask.imgid=main.history.imgid)",
             "[init] can't update `num' with num+1\n");

    // update history end
    TRY_EXEC("UPDATE main.images SET history_end = history_end+1 WHERE id IN (SELECT imgid FROM main.mask WHERE main.mask.imgid=main.images.id)",
             "[init] can't update `history_end' with history_end+1\n");

    // copy all masks into history
    TRY_EXEC("INSERT INTO main.masks_history (imgid, num, formid, form, name, version, points, points_count, source) SELECT "
             "imgid, 0, formid, form, name, version, points, points_count, source FROM main.mask",
             "[init] can't insert into masks_history\n");

    // create a mask manager entry for each image that has masks
    TRY_EXEC("INSERT INTO main.history (imgid, num, operation, op_params, module, enabled, "
             "blendop_params, blendop_version, multi_priority, multi_name) "
             "SELECT DISTINCT imgid, 0, 'mask_manager', NULL, 1, 0, NULL, 0, 0, '' FROM main.mask "
             "GROUP BY imgid",
             "[init] can't insert mask manager into history\n");

    TRY_EXEC("DROP TABLE main.mask", "[init] can't drop table `mask' from database\n");

    ////////////////////////////// custom iop order
    GList *prior_v1 = dt_ioppr_get_iop_order_list_version(DT_IOP_ORDER_LEGACY);

    TRY_EXEC("ALTER TABLE main.images ADD COLUMN iop_order_version INTEGER",
             "[init] can't add `iop_order_version' column to images table in database\n");

    TRY_EXEC("UPDATE main.images SET iop_order_version = 0",
             "[init] can't update iop_order_version in database\n");

    TRY_EXEC("UPDATE main.images SET iop_order_version = 1 WHERE "
             "EXISTS(SELECT * FROM main.history WHERE main.history.imgid = main.images.id)",
             "[init] can't update iop_order_version in database\n");

    TRY_EXEC("ALTER TABLE main.history ADD COLUMN iop_order REAL",
             "[init] can't add `iop_order' column to history table in database\n");

    // create a temp table with the previous priorities
    TRY_EXEC("CREATE TEMPORARY TABLE iop_order_tmp (iop_order REAL, operation VARCHAR(256))",
             "[init] can't create temporary table for updating `main.history'\n");
    // clang-format on
    // fill temp table with all operations up to this release
    // it will be used to create the pipe and update the iop_order on history
    for(GList *priorities = prior_v1; priorities; priorities = g_list_next(priorities))
    {
      dt_iop_order_entry_t *prior = (dt_iop_order_entry_t *)priorities->data;

      sqlite3_prepare_v2(
          db->handle,
          "INSERT INTO iop_order_tmp (iop_order, operation) VALUES (?1, ?2)",
          -1, &stmt, NULL);
      sqlite3_bind_double(stmt, 1, prior->o.iop_order_f);
      sqlite3_bind_text(stmt, 2, prior->operation, -1, SQLITE_TRANSIENT);
      TRY_STEP(stmt, SQLITE_DONE, "[init] can't insert default value in iop_order_tmp\n");
      sqlite3_finalize(stmt);
    }
    g_list_free_full(prior_v1, free);

    // create the order of the pipe
    // iop_order is by default the module priority
    // if there's multi-instances we add the multi_priority
    // multi_priority is in reverse order in this version,
    // so we assume that is always less than 1000 and reverse it
    // it is possible that multi_priority = 0 don't appear in history
    // so just in case 1 / 1000 to every instance
    // clang-format off
    TRY_EXEC("UPDATE main.history SET iop_order = ((("
        "SELECT MAX(multi_priority) FROM main.history hist1 WHERE hist1.imgid = main.history.imgid AND hist1.operation = main.history.operation "
             ") + 1. - multi_priority) / 1000.) + "
             "IFNULL((SELECT iop_order FROM iop_order_tmp WHERE iop_order_tmp.operation = "
             "main.history.operation), -999999.) ",
             "[init] can't update iop_order in history table\n");

    // check if there's any entry in history that was not updated
    sqlite3_stmt *sel_stmt;
    TRY_PREPARE(sel_stmt, "SELECT DISTINCT operation FROM main.history WHERE iop_order <= 0 OR iop_order IS NULL",
                "[init] can't prepare selecting history iop_order\n");
    // clang-format on
    while(sqlite3_step(sel_stmt) == SQLITE_ROW)
    {
      const char *op_name = (const char *)sqlite3_column_text(sel_stmt, 0);
      printf("operation %s with no iop_order while upgrading database\n", op_name);
    }
    sqlite3_finalize(sel_stmt);
    // clang-format off
    TRY_EXEC("DROP TABLE iop_order_tmp", "[init] can't drop table `iop_order_tmp' from database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 18;
  }
  // maybe in the future, see commented out code elsewhere
  //   else if(version == XXX)
  //   {
  //     sqlite3_exec(db->handle, "ALTER TABLE film_rolls ADD COLUMN external_drive VARCHAR(1024)", NULL,
  //     NULL, NULL);
  //   }
  else if(version == 18)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("UPDATE images SET orientation=-2 WHERE orientation=1;",
             "[init] can't update images orientation 1 from database\n");

    TRY_EXEC("UPDATE images SET orientation=1 WHERE orientation=2;",
             "[init] can't update images orientation 2 from database\n");

    TRY_EXEC("UPDATE images SET orientation=-6 WHERE orientation=5;",
             "[init] can't update images orientation 5 from database\n");

    TRY_EXEC("UPDATE images SET orientation=5 WHERE orientation=6;",
             "[init] can't update images orientation 6 from database\n");

    TRY_EXEC("UPDATE images SET orientation=2 WHERE orientation=-2;",
             "[init] can't update images orientation -1 from database\n");

    TRY_EXEC("UPDATE images SET orientation=6 WHERE orientation=-6;",
             "[init] can't update images orientation -6 from database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 19;
  }
  else if(version == 19)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // create a temp table to invert all multi_priority
    TRY_EXEC("CREATE TEMPORARY TABLE m_prio (id INTEGER, operation VARCHAR(256), prio INTEGER)",
             "[init] can't create temporary table for updating `history and style_items'\n");

    TRY_EXEC("CREATE INDEX m_prio_id_index ON m_prio (id)",
             "[init] can't create temporary index for updating `history and style_items'\n");
    TRY_EXEC("CREATE INDEX m_prio_op_index ON m_prio (operation)",
             "[init] can't create temporary index for updating `history and style_items'\n");

    TRY_EXEC("INSERT INTO m_prio SELECT imgid, operation, MAX(multi_priority)"
             " FROM main.history GROUP BY imgid, operation",
             "[init] can't populate m_prio\n");

    TRY_EXEC("UPDATE main.history SET multi_priority = "
             "(SELECT prio FROM m_prio "
             " WHERE main.history.operation = operation AND main.history.imgid = id) - main.history.multi_priority",
             "[init] can't update multi_priority for history\n");

    TRY_EXEC("DROP TABLE m_prio", "[init] can't drop table `m_prio' from database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 20;
  }
  else if(version == 20)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("DROP INDEX IF EXISTS main.used_tags_idx", "[init] can't drop index `used_tags_idx' from database\n");
    TRY_EXEC("DROP TABLE used_tags", "[init] can't delete table used_tags\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 21;
  }
  else if(version == 21)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // create a temp table to invert all multi_priority
    // clang-format off
    TRY_EXEC("CREATE TABLE module_order (imgid INTEGER PRIMARY KEY, version INTEGER, iop_list VARCHAR)",
             "[init] can't create module_order table'\n");

    // for all images:
    sqlite3_stmt *mig_stmt;
    TRY_PREPARE(mig_stmt, "SELECT imgid, operation, multi_priority, iop_order, mi.iop_order_version"
                          " FROM main.history AS hi, main.images AS mi"
                          " WHERE hi.imgid = mi.id"
                          " GROUP BY imgid, operation, multi_priority"
                          " ORDER BY imgid, iop_order",
                "[init] can't prepare selecting history for iop_order migration (v21)\n");
    // clang-format on
    GList *item_list = NULL;
    int current_imgid = -1;
    int current_order_version = -1;

    gboolean has_row = (sqlite3_step(mig_stmt) == SQLITE_ROW);

    while(has_row)
    {
      const int32_t imgid = sqlite3_column_int(mig_stmt, 0);
      char operation[20] = { 0 };
      g_strlcpy(operation, (const char *)sqlite3_column_text(mig_stmt, 1), sizeof(operation));
      const int multi_priority = sqlite3_column_int(mig_stmt, 2);
      const double iop_order = sqlite3_column_double(mig_stmt, 3);
      const int iop_order_version = sqlite3_column_int(mig_stmt, 4);

      has_row = (sqlite3_step(mig_stmt) == SQLITE_ROW);

      // a new image, let's initialize the iop_order_version
      if(imgid != current_imgid || !has_row)
      {
        // new image, let's handle it
        if(item_list != NULL)
        {
          // we keep legacy, everything else is migrated to v3.0
          const dt_iop_order_t new_order_version = current_order_version == 2 ? DT_IOP_ORDER_LEGACY : DT_IOP_ORDER_V30;

          GList *iop_order_list = dt_ioppr_get_iop_order_list_version(new_order_version);

          // merge entries into iop_order_list

          // first remove all item_list iop from the iop_order_list

          GList *e = item_list;
          GList *n = NULL;
          dt_iop_order_entry_t *n_entry = NULL;

          while(e)
          {
            dt_iop_order_entry_t *e_entry = (dt_iop_order_entry_t *)e->data;

            GList *s = iop_order_list;
            while(s && strcmp(((dt_iop_order_entry_t *)s->data)->operation, e_entry->operation))
            {
              s = g_list_next(s);
            }
            if(s)
            {
              iop_order_list = g_list_delete_link(iop_order_list, s);
            }

            // skip all multipe instances
            n = e;
            do
            {
              n = g_list_next(n);
              if(!n) break;
              n_entry = (dt_iop_order_entry_t *)n->data;
            } while(!strcmp(n_entry->operation, e_entry->operation));
            e = n;
          }

          // then add all item_list into iop_order_list

          for(e = item_list; e; e = g_list_next(e))
          {
            dt_iop_order_entry_t *e_entry = (dt_iop_order_entry_t *)e->data;
            iop_order_list = g_list_prepend(iop_order_list, e_entry);
          }

          // and finally reorder the full list based on the iop-order

          iop_order_list = g_list_sort(iop_order_list, dt_sort_iop_list_by_order_f);

          const dt_iop_order_t kind = dt_ioppr_get_iop_order_list_kind(iop_order_list);

          // check if we have some multi-instances

          gboolean has_multiple_instances = FALSE;
          GList *l = iop_order_list;

          while(l)
          {
            GList *next = g_list_next(l);
            if(next
               && (strcmp(((dt_iop_order_entry_t *)(l->data))->operation,
                          ((dt_iop_order_entry_t *)(next->data))->operation) == 0))
            {
              has_multiple_instances = TRUE;
              break;
            }
            l = next;
          }

          // write iop_order_list and/or version into module_order

          sqlite3_stmt *ins_stmt = NULL;
          if(kind == DT_IOP_ORDER_CUSTOM || has_multiple_instances)
          {
            char *iop_list_txt = dt_ioppr_serialize_text_iop_order_list(iop_order_list);

            sqlite3_prepare_v2(db->handle,
                               "INSERT INTO module_order VALUES (?1, ?2, ?3)", -1,
                               &ins_stmt, NULL);
            sqlite3_bind_int(ins_stmt, 1, current_imgid);
            sqlite3_bind_int(ins_stmt, 2, kind);
            sqlite3_bind_text(ins_stmt, 3, iop_list_txt, -1, SQLITE_TRANSIENT);
            TRY_STEP(ins_stmt, SQLITE_DONE, "[init] can't insert into module_order (custom order)\n");
            sqlite3_finalize(ins_stmt);

            g_free(iop_list_txt);
          }
          else
          {
            sqlite3_prepare_v2(db->handle,
                               "INSERT INTO module_order VALUES (?1, ?2, NULL)", -1,
                               &ins_stmt, NULL);
            sqlite3_bind_int(ins_stmt, 1, current_imgid);
            sqlite3_bind_int(ins_stmt, 2, kind);
            TRY_STEP(ins_stmt, SQLITE_DONE, "[init] can't insert into module_order (standard order)\n");
            sqlite3_finalize(ins_stmt);
          }

          g_list_free(item_list);
          g_list_free_full(iop_order_list, free);

          item_list = NULL;
        }

        current_imgid = imgid;
        current_order_version = iop_order_version;
      }

      dt_iop_order_entry_t *item = (dt_iop_order_entry_t *)malloc(sizeof(dt_iop_order_entry_t));
      memcpy(item->operation, operation, sizeof(item->operation));
      item->instance = multi_priority;
      item->o.iop_order_f = iop_order; // used to order the enties only
      item_list = g_list_append(item_list, item);
    }
    sqlite3_finalize(mig_stmt);

    // remove iop_order from history table
    // clang-format off
    TRY_EXEC("CREATE TABLE h (imgid INTEGER, num INTEGER, module INTEGER, "
             "operation VARCHAR(256), op_params BLOB, enabled INTEGER, "
             "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
             "[init] can't create module_order table\n");
    TRY_EXEC("CREATE INDEX h_imgid_index ON h (imgid)",
             "[init] can't create index h_imgid_index\n");
    TRY_EXEC("INSERT INTO h SELECT imgid, num, module, operation, op_params, enabled, "
             "blendop_params, blendop_version, multi_priority, multi_name FROM main.history",
             "[init] can't create module_order table\n");
    TRY_EXEC("DROP TABLE history",
             "[init] can't drop table history\n");
    TRY_EXEC("ALTER TABLE h RENAME TO history",
             "[init] can't rename h to history\n");
    TRY_EXEC("DROP INDEX h_imgid_index",
             "[init] can't drop index h_imgid_index\n");
    TRY_EXEC("CREATE INDEX main.history_imgid_index ON history (imgid)",
             "[init] can't create index images_imgid_index\n");

    // remove iop_order_version from images

    TRY_EXEC("CREATE TABLE i (id INTEGER PRIMARY KEY AUTOINCREMENT, group_id INTEGER, film_id INTEGER, "
             "width INTEGER, height INTEGER, filename VARCHAR, maker VARCHAR, model VARCHAR, "
             "lens VARCHAR, exposure REAL, aperture REAL, iso REAL, focal_length REAL, "
             "focus_distance REAL, datetime_taken CHAR(20), flags INTEGER, "
             "output_width INTEGER, output_height INTEGER, crop REAL, "
             "raw_parameters INTEGER, raw_denoise_threshold REAL, "
             "raw_auto_bright_threshold REAL, raw_black INTEGER, raw_maximum INTEGER, "
             "caption VARCHAR, description VARCHAR, license VARCHAR, sha1sum CHAR(40), "
             "orientation INTEGER, histogram BLOB, lightmap BLOB, longitude REAL, "
             "latitude REAL, altitude REAL, color_matrix BLOB, colorspace INTEGER, version INTEGER, "
             "max_version INTEGER, write_timestamp INTEGER, history_end INTEGER, position INTEGER, aspect_ratio REAL)",
             "[init] can't create table i\n");
    TRY_EXEC("INSERT INTO i SELECT id, group_id, film_id, width, height, filename, maker, model,"
             " lens, exposure, aperture, iso, focal_length, focus_distance, datetime_taken, flags,"
             " output_width, output_height, crop, raw_parameters, raw_denoise_threshold,"
             " raw_auto_bright_threshold, raw_black, raw_maximum, caption, description, license, sha1sum,"
             " orientation, histogram, lightmap, longitude, latitude, altitude, color_matrix, colorspace, version,"
             " max_version, write_timestamp, history_end, position, aspect_ratio "
             "FROM images",
             "[init] can't populate table h\n");
    TRY_EXEC("DROP TABLE images",
             "[init] can't drop table images\n");
    TRY_EXEC("ALTER TABLE i RENAME TO images",
             "[init] can't rename i to images\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 22;
  }
  else if(version == 22)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.images_group_id_index ON images (group_id)",
             "[init] can't create group_id index on image\n");
    TRY_EXEC("CREATE INDEX IF NOT EXISTS  main.images_film_id_index ON images (film_id)",
             "[init] can't create film_id index on image\n");
    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.images_filename_index ON images (filename)",
             "[init] can't create filename index on image\n");
    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.image_position_index ON images (position)",
             "[init] can't create position index on image\n");

    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.film_rolls_folder_index ON film_rolls (folder)",
             "[init] can't create folder index on film_rolls\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 23;
  }
  else if(version == 23)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("CREATE TABLE main.history_hash (imgid INTEGER PRIMARY KEY, "
             "basic_hash BLOB, auto_hash BLOB, current_hash BLOB)",
             "[init] can't create table history_hash\n");
    // clang-format on

    // use the former dt_image_altered() to initialise the history_hash table
    // insert an history_hash entry for all images which have an history
    // note that images without history don't get hash and are considered as basic
    sqlite3_stmt *h_stmt;
    const gboolean basecurve_auto_apply = dt_conf_is_equal("plugins/darkroom/workflow", "display-referred");
    const gboolean sharpen_auto_apply = dt_conf_get_bool("plugins/darkroom/sharpen/auto_apply");
    // clang-format off
    char *query = g_strdup_printf(
                            "SELECT id, CASE WHEN imgid IS NULL THEN 0 ELSE 1 END as altered "
                            // first, images which are both in images and history (avoids history orphans)
                            "FROM (SELECT DISTINCT id FROM main.images JOIN main.history ON imgid = id) "
                            "LEFT JOIN (SELECT DISTINCT imgid FROM main.images JOIN main.history ON imgid = id "
                            "           WHERE num < history_end AND enabled = 1"
                            "             AND operation NOT IN ('flip', 'dither', 'highlights', 'rawprepare', "
                            "             'colorin', 'colorout', 'gamma', 'demosaic', 'temperature'%s%s)) "
                            "ON imgid = id",
                             basecurve_auto_apply ? ", 'basecurve'" : "",
                             sharpen_auto_apply ? ", 'sharpen'" : "");
    // clang-format on
    TRY_PREPARE(h_stmt, query,
                "[init] can't prepare selecting history for history_hash migration\n");
    while(sqlite3_step(h_stmt) == SQLITE_ROW)
    {
      const int32_t imgid= sqlite3_column_int(h_stmt, 0);
      const int32_t altered = sqlite3_column_int(h_stmt, 1);

      guint8 *hash = NULL;
      GChecksum *checksum = g_checksum_new(G_CHECKSUM_MD5);
      gsize hash_len = 0;

      // get history
      sqlite3_stmt *h2_stmt;
      // clang-format off
      sqlite3_prepare_v2(db->handle,
                         "SELECT operation, op_params, blendop_params"
                         " FROM main.history"
                         " WHERE imgid = ?1 AND enabled = 1"
                         " ORDER BY num",
                         -1, &h2_stmt, NULL);
      // clang-format on
      sqlite3_bind_int(h2_stmt, 1, imgid);
      while(sqlite3_step(h2_stmt) == SQLITE_ROW)
      {
        // operation
        char *buf = (char *)sqlite3_column_text(h2_stmt, 0);
        if(buf) g_checksum_update(checksum, (const guchar *)buf, -1);
        // op_params
        buf = (char *)sqlite3_column_blob(h2_stmt, 1);
        int params_len = sqlite3_column_bytes(h2_stmt, 1);
        if(buf) g_checksum_update(checksum, (const guchar *)buf, params_len);
        // blendop_params
        buf = (char *)sqlite3_column_blob(h2_stmt, 2);
        params_len = sqlite3_column_bytes(h2_stmt, 2);
        if(buf) g_checksum_update(checksum, (const guchar *)buf, params_len);
      }
      sqlite3_finalize(h2_stmt);

      // get module order
      h2_stmt = NULL;
      // clang-format off
      sqlite3_prepare_v2(db->handle,
                         "SELECT version, iop_list"
                         " FROM main.module_order"
                         " WHERE imgid = ?1",
                         -1, &h2_stmt, NULL);
      // clang-format on
      sqlite3_bind_int(h2_stmt, 1, imgid);
      if(sqlite3_step(h2_stmt) == SQLITE_ROW)
      {
        const int version_h = sqlite3_column_int(h2_stmt, 0);
        g_checksum_update(checksum, (const guchar *)&version_h, sizeof(version_h));
        if(version_h == DT_IOP_ORDER_CUSTOM)
        {
          // iop_list
          const char *buf = (char *)sqlite3_column_text(h2_stmt, 1);
          if(buf) g_checksum_update(checksum, (const guchar *)buf, -1);
        }
      }
      sqlite3_finalize(h2_stmt);

      const gsize checksum_len = g_checksum_type_get_length(G_CHECKSUM_MD5);
      hash = g_malloc(checksum_len);
      hash_len = checksum_len;
      g_checksum_get_digest(checksum, hash, &hash_len);

      g_checksum_free(checksum);
      // insert the hash for that image
      h2_stmt = NULL;
      // clang-format off
      sqlite3_prepare_v2(db->handle,
                         "INSERT INTO main.history_hash"
                         " VALUES (?1, ?2, NULL, ?3)",
                         -1, &h2_stmt, NULL);
      // clang-format on
      sqlite3_bind_int(h2_stmt, 1, imgid);
      sqlite3_bind_blob(h2_stmt, 2, altered ? NULL : hash, altered ? 0 : hash_len, SQLITE_TRANSIENT);
      sqlite3_bind_blob(h2_stmt, 3, hash, hash_len, SQLITE_TRANSIENT);
      TRY_STEP(h2_stmt, SQLITE_DONE, "[init] can't insert into history_hash\n");
      sqlite3_finalize(h2_stmt);
      g_free(hash);
    }
    sqlite3_finalize(h_stmt);
    g_free(query);

    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 24;
  }
  else if(version == 24)
  {
    // clang-format off
    TRY_EXEC("ALTER TABLE main.history_hash ADD COLUMN mipmap_hash BLOB",
             "[init] can't add `mipmap_hash' column to history_hash table in database\n");
    // clang-format on

    new_version = 25;
  }
  else if(version == 25)
  {
    // clang-format of
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN exposure_bias REAL",
             "[init] can't add `exposure_bias' column to images table in database\n");
    // clang-format on

    new_version = 26;
  }
  else if(version == 26)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("CREATE TABLE main.new_film_rolls "
             "(id INTEGER PRIMARY KEY, "
             "access_timestamp INTEGER, "
             "folder VARCHAR(1024) NOT NULL)",
             "[init] can't create new_film_rolls table\n");

    TRY_EXEC("INSERT INTO main.new_film_rolls"
             "(id, access_timestamp, folder) "
             "SELECT id, "
             "strftime('%s', replace(substr(datetime_accessed, 1, 10), ':', '-') || substr(datetime_accessed, 11), 'utc'), "
             "folder "
             "FROM film_rolls "
             "WHERE folder IS NOT NULL",
             "[init] can't populate new_film_rolls table from film_rolls\n");

    TRY_EXEC("DROP TABLE film_rolls",
             "[init] can't delete table film_rolls\n");

    TRY_EXEC("ALTER TABLE main.new_film_rolls RENAME TO film_rolls",
             "[init] can't rename table new_film_rolls to film_rolls\n");

    TRY_EXEC("CREATE INDEX main.film_rolls_folder_index ON film_rolls (folder)",
             "[init] can't create index `film_rolls_folder_index' on table `film_rolls'\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 27;
  }
  else if(version == 27)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN import_timestamp INTEGER DEFAULT -1",
             "[init] can't add `import_timestamp' column to images table in database\n");
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN change_timestamp INTEGER DEFAULT -1",
             "[init] can't add `change_timestamp' column to images table in database\n");
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN export_timestamp INTEGER DEFAULT -1",
             "[init] can't add `export_timestamp' column to images table in database\n");
    TRY_EXEC("ALTER TABLE main.images ADD COLUMN print_timestamp INTEGER DEFAULT -1",
             "[init] can't add `print_timestamp' column to images table in database\n");

    TRY_EXEC("UPDATE main.images SET import_timestamp = (SELECT access_timestamp "
               "FROM main.film_rolls WHERE film_rolls.id = images.film_id)",
             "[init] can't populate import_timestamp column from film_rolls.access_timestamp.\n");

    TRY_EXEC("UPDATE main.images SET change_timestamp = images.write_timestamp "
               "WHERE images.write_timestamp IS NOT NULL "
                 "AND images.id = (SELECT imgid FROM tagged_images "
                   "JOIN data.tags ON tags.id = tagged_images.tagid "
                     "WHERE data.tags.name = 'darktable|changed')",
             "[init] can't populate change_timestamp column from images.write_timestamp.\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 28;
  }
  else if(version == 28)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // clear flag DT_IMAGE_REJECTED (was not used)
    TRY_EXEC("UPDATE main.images SET flags = (flags & ~8)",
             "[init] can't clear rejected flags");

    // add DT_IMAGE_REJECTED and clear rating for all images being rejected
    TRY_EXEC("UPDATE main.images SET flags = (flags | 8) & ~7 WHERE (flags & 7) = 6",
             "[init] can't set rejected flags");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 29;
  }
  else if(version == 29)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // add position in tagged_images table
    TRY_EXEC("ALTER TABLE main.tagged_images ADD COLUMN position INTEGER",
             "[init] can't add `position' column to tagged_images table in database\n");

    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.tagged_images_imgid_index ON tagged_images (imgid)",
             "[init] can't create image index on tagged_images\n");
    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.tagged_images_position_index ON tagged_images (position)",
             "[init] can't create position index on tagged_images\n");
    TRY_EXEC("UPDATE main.tagged_images SET position = (tagid + imgid) << 32",
             "[init] can't populate position on tagged_images\n");

    // remove caption and description fields from images table

    TRY_EXEC("CREATE TABLE main.i (id INTEGER PRIMARY KEY AUTOINCREMENT, group_id INTEGER, film_id INTEGER, "
             "width INTEGER, height INTEGER, filename VARCHAR, maker VARCHAR, model VARCHAR, "
             "lens VARCHAR, exposure REAL, aperture REAL, iso REAL, focal_length REAL, "
             "focus_distance REAL, datetime_taken CHAR(20), flags INTEGER, "
             "output_width INTEGER, output_height INTEGER, crop REAL, "
             "raw_parameters INTEGER, raw_denoise_threshold REAL, "
             "raw_auto_bright_threshold REAL, raw_black INTEGER, raw_maximum INTEGER, "
             "license VARCHAR, sha1sum CHAR(40), "
             "orientation INTEGER, histogram BLOB, lightmap BLOB, longitude REAL, "
             "latitude REAL, altitude REAL, color_matrix BLOB, colorspace INTEGER, version INTEGER, "
             "max_version INTEGER, write_timestamp INTEGER, history_end INTEGER, position INTEGER, "
             "aspect_ratio REAL, exposure_bias REAL, "
             "import_timestamp INTEGER DEFAULT -1, change_timestamp INTEGER DEFAULT -1, "
             "export_timestamp INTEGER DEFAULT -1, print_timestamp INTEGER DEFAULT -1)",
             "[init] can't create table i\n");

    TRY_EXEC("INSERT INTO main.i SELECT id, group_id, film_id, width, height, filename, maker, model,"
             " lens, exposure, aperture, iso, focal_length, focus_distance, datetime_taken, flags,"
             " output_width, output_height, crop, raw_parameters, raw_denoise_threshold,"
             " raw_auto_bright_threshold, raw_black, raw_maximum, license, sha1sum,"
             " orientation, histogram, lightmap, longitude, latitude, altitude, color_matrix, colorspace, version,"
             " max_version, write_timestamp, history_end, position, aspect_ratio, exposure_bias,"
             " import_timestamp, change_timestamp, export_timestamp, print_timestamp "
             "FROM main.images",
             "[init] can't populate table i\n");
    TRY_EXEC("DROP TABLE main.images",
             "[init] can't drop table images\n");
    TRY_EXEC("ALTER TABLE main.i RENAME TO images",
             "[init] can't rename i to images\n");

    TRY_EXEC("CREATE INDEX main.images_group_id_index ON images (group_id)",
          "[init] can't create group_id index on images table\n");
    TRY_EXEC("CREATE INDEX main.images_film_id_index ON images (film_id)",
          "[init] can't create film_id index on images table\n");
    TRY_EXEC("CREATE INDEX main.images_filename_index ON images (filename)",
          "[init] can't create filename index on images table\n");
    TRY_EXEC("CREATE INDEX main.image_position_index ON images (position)",
          "[init] can't create position index on images table\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 30;
  }
  else if(version == 30)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // add second columns to speed up sorting
    TRY_EXEC("DROP INDEX IF EXISTS `history_imgid_index`",
        "[init] can't drop history_imgid_index\n");
    TRY_EXEC("CREATE INDEX `history_imgid_index` ON `history` ( `imgid`, `operation` )",
        "[init] can't recreate history_imgid_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `images_filename_index`",
        "[init] can't drop images_filename_index\n");
    TRY_EXEC("CREATE INDEX `images_filename_index` ON `images` ( `filename`, `version` )",
        "[init] can't recreate images_filename_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `images_film_id_index`",
        "[init] can't drop images_film_id_index\n");
    TRY_EXEC("CREATE INDEX `images_film_id_index` ON `images` ( `film_id`, `filename` )",
        "[init] can't recreate images_film_id_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `images_group_id_index`",
        "[init] can't drop images_group_id_index\n");
    TRY_EXEC("CREATE INDEX `images_group_id_index` ON `images` ( `group_id`, `id` )",
        "[init] can't recreate images_group_id_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `masks_history_imgid_index`",
        "[init] can't drop masks_history_imgid_index\n");
    TRY_EXEC("CREATE INDEX `masks_history_imgid_index` ON `masks_history` ( `imgid`, `num` )",
        "[init] can't recreate masks_history_imgid_index\n");

    // map refinement: avoid full table scan
    TRY_EXEC("CREATE INDEX `images_latlong_index` ON `images` ( `latitude` DESC, `longitude` DESC )",
        "[init] can't create images_latlong_index\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 31;
  }
  else if(version == 31)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // remove duplicates
    TRY_EXEC("DELETE FROM main.meta_data WHERE rowid NOT IN (SELECT MIN(rowid) "
             "FROM main.meta_data GROUP BY id, key)",
             "[init] can't remove duplicates from meta_data\n");

    // recreate the index with UNIQUE option
    TRY_EXEC("DROP INDEX IF EXISTS metadata_index",
             "[init] can't drop metadata_index\n");
    TRY_EXEC("CREATE UNIQUE INDEX main.metadata_index ON meta_data (id, key)",
             "[init] can't create metadata_index\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 32;
  }
  else if(version == 32)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // add foreign keys for database consistency. ON UPDATE CASCADE since you never know
    // if a future version will change image_id
    // Unfortunately sqlite does not support adding foreign keys to existing tables
    // so we have to rename the existing tables, recreate them and copy back the old values
    // images first
    // needs to delete orphaned entries
    TRY_EXEC("ALTER TABLE `images` RENAME TO `images_old`",
        "[init] can't rename images\n");

    TRY_EXEC("CREATE TABLE `images` (id INTEGER PRIMARY KEY AUTOINCREMENT, group_id INTEGER, film_id INTEGER, "
      "width INTEGER, height INTEGER, filename VARCHAR, maker VARCHAR, model VARCHAR, lens VARCHAR, "
      "exposure REAL, aperture REAL, iso REAL, focal_length REAL, focus_distance REAL, datetime_taken CHAR(20), "
      "flags INTEGER, output_width INTEGER, output_height INTEGER, crop REAL, "
      "raw_parameters INTEGER, raw_denoise_threshold REAL, raw_auto_bright_threshold REAL, "
      "raw_black INTEGER, raw_maximum INTEGER, license VARCHAR, sha1sum CHAR(40), "
      "orientation INTEGER, histogram BLOB, lightmap BLOB, longitude REAL, latitude REAL, altitude REAL, "
      "color_matrix BLOB, colorspace INTEGER, version INTEGER, max_version INTEGER, write_timestamp INTEGER, "
      "history_end INTEGER, position INTEGER, aspect_ratio REAL, exposure_bias REAL, "
      "import_timestamp INTEGER DEFAULT -1, change_timestamp INTEGER DEFAULT -1, export_timestamp INTEGER DEFAULT -1, print_timestamp INTEGER DEFAULT -1, "
      "FOREIGN KEY(film_id) REFERENCES film_rolls(id) ON DELETE CASCADE ON UPDATE CASCADE, "
      "FOREIGN KEY(group_id) REFERENCES images(id) ON DELETE RESTRICT ON UPDATE CASCADE)",
        "[init] can't create new images table\n");

    // corner case: database inconsistency with images having invalid film id
    TRY_EXEC("DELETE FROM `images_old` WHERE film_id NOT IN (SELECT id FROM `film_rolls`)",
        "[init] can't delete images with invalid film id\n");

    TRY_EXEC("UPDATE `images_old` SET group_id=id WHERE group_id NOT IN (SELECT id from `images_old`)",
        "[init] can't fix invalid group ids\n");

    TRY_EXEC("INSERT INTO `images` SELECT * FROM `images_old`",
        "[init] can't copy back from images_old\n");

    // pita: need to recreate index
    TRY_EXEC("DROP INDEX IF EXISTS `image_position_index`",
        "[init] can't drop image_position_index\n");
    TRY_EXEC("CREATE INDEX `image_position_index` ON `images` (position)",
        "[init] can't add image_position_index\n");

    // second columns
    TRY_EXEC("DROP INDEX IF EXISTS `images_filename_index`",
        "[init] can't drop images_filename_index\n");
    TRY_EXEC("CREATE INDEX `images_filename_index` ON `images` ( `filename`, `version` )",
        "[init] can't recreate images_filename_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `images_film_id_index`",
        "[init] can't drop images_film_id_index\n");
    TRY_EXEC("CREATE INDEX `images_film_id_index` ON `images` ( `film_id`, `filename` )",
        "[init] can't recreate images_film_id_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `images_group_id_index`",
        "[init] can't drop images_group_id_index\n");
    TRY_EXEC("CREATE INDEX `images_group_id_index` ON `images` ( `group_id`, `id` )",
        "[init] can't recreate images_group_id_index\n");

    TRY_EXEC("DROP INDEX IF EXISTS `images_latlong_index`",
        "[init] can't drop images_latlong_index\n");
    TRY_EXEC("CREATE INDEX `images_latlong_index` ON `images` ( latitude DESC, longitude DESC )",
        "[init] can't add images_latlong_index\n");

    TRY_EXEC("DROP TABLE `images_old`",
        "[init] can't drop table images_old\n");

    // history
    TRY_EXEC("ALTER TABLE `history` RENAME TO `history_old`",
        "[init] can't rename history\n");

    TRY_EXEC("CREATE TABLE `history` (imgid INTEGER, num INTEGER, module INTEGER, "
      "operation VARCHAR(256), op_params BLOB, enabled INTEGER, blendop_params BLOB, blendop_version INTEGER, "
      "multi_priority INTEGER, multi_name VARCHAR(256), "
      "FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new history table\n");

    TRY_EXEC("DELETE FROM `history_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
        "[init] can't delete orphaned history elements\n");

    TRY_EXEC("INSERT INTO history SELECT * FROM history_old",
         "[init] can't copy back from history_old\n");

    TRY_EXEC("DROP INDEX IF EXISTS `history_imgid_index`",
        "[init] can't drop history_imgid_index\n");
    TRY_EXEC("CREATE INDEX `history_imgid_op_index` ON `history` ( `imgid`, `operation` )",
        "[init] can't recreate history_imgid_index\n");
    TRY_EXEC("CREATE INDEX `history_imgid_num_index` ON `history` ( `imgid`, `num` DESC )",
        "[init] can't recreate history_imgid_index\n");

    TRY_EXEC("DROP TABLE `history_old`",
        "[init] can't drop table history_old\n");

    // history hash
    TRY_EXEC("ALTER TABLE `history_hash` RENAME TO `history_hash_old`",
         "[init] can't rename history_hash\n");

    TRY_EXEC("CREATE TABLE `history_hash` (imgid INTEGER PRIMARY KEY, basic_hash BLOB, auto_hash BLOB, current_hash BLOB, "
      "mipmap_hash BLOB, FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new history_hash table\n");

    TRY_EXEC("DELETE FROM `history_hash_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
        "[init] can't delete orphaned history_hash elements\n");

    TRY_EXEC("INSERT INTO `history_hash` SELECT * FROM `history_hash_old`",
         "[init] can't copy back from history_hash_old\n");

    TRY_EXEC("DROP TABLE `history_hash_old`",
        "[init] can't drop table history_hash_old\n");

    // tagged images
    TRY_EXEC("ALTER TABLE `tagged_images` RENAME TO `tagged_images_old`",
         "[init] can't rename tagged_images\n");

    TRY_EXEC("CREATE TABLE `tagged_images` (imgid integer, tagid integer, position INTEGER, "
        "primary key(imgid, tagid), FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new tagged_images table\n");

    TRY_EXEC("DELETE FROM `tagged_images_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
        "[init] can't delete orphaned tagged_images elements\n");

    TRY_EXEC("INSERT INTO `tagged_images` SELECT * FROM `tagged_images_old`",
         "[init] can't copy back from tagged_images_old\n");

    // old indices
    TRY_EXEC("DROP INDEX IF EXISTS tagged_images_imgid_index",
        "[init] can't drop tagged_images_imgid_index\n");
    TRY_EXEC("DROP INDEX IF EXISTS tagged_images_position_index",
        "[init] can't drop tagged_images_position_index\n");
    TRY_EXEC("CREATE INDEX tagged_images_position_index ON tagged_images (position)",
        "[init] can't add index tagged_images_position_index\n");
    TRY_EXEC("DROP INDEX IF EXISTS tagged_images_tagid_index",
        "[init] can't drop tagged_images_tagid_index\n");
    TRY_EXEC("CREATE INDEX tagged_images_tagid_index ON tagged_images (tagid)",
        "[init] can't add index tagged_images_tagid_index\n");

    TRY_EXEC("DROP TABLE `tagged_images_old`",
        "[init] can't drop table tagged_images_old\n");

    // masks history
    TRY_EXEC("ALTER TABLE `masks_history` RENAME TO `masks_history_old`",
         "[init] can't rename masks_history\n");

    TRY_EXEC("CREATE TABLE masks_history (imgid INTEGER, num INTEGER, formid INTEGER, form INTEGER, "
        "name VARCHAR(256), version INTEGER, points BLOB, points_count INTEGER, source BLOB, "
        "FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new masks_history table\n");

    TRY_EXEC("DELETE FROM `masks_history_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
        "[init] can't delete orphaned masks_history elements\n");

    TRY_EXEC("INSERT INTO `masks_history` SELECT * FROM `masks_history_old`",
         "[init] can't copy back from masks_history\n");

    TRY_EXEC("DROP INDEX IF EXISTS `masks_history_imgid_index`",
        "[init] can't drop masks_history_imgid_index\n");
    TRY_EXEC("CREATE INDEX `masks_history_imgid_index` ON `masks_history` ( imgid, num )",
        "[init] can't recreate masks_history_imgid_index\n");

    TRY_EXEC("DROP TABLE masks_history_old",
        "[init] can't drop table masks_history_old\n");

    // color labels
    TRY_EXEC("ALTER TABLE `color_labels` RENAME TO `color_labels_old`",
         "[init] can't rename color_labels\n");
    TRY_EXEC("CREATE TABLE `color_labels` (imgid INTEGER, color INTEGER, "
      "FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new color_labels table\n");

    TRY_EXEC("DELETE FROM `color_labels_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
        "[init] can't delete orphaned color_labels elements\n");

    TRY_EXEC("INSERT INTO `color_labels` SELECT * FROM `color_labels_old`",
         "[init] can't copy back from color_labels\n");

    TRY_EXEC("DROP TABLE color_labels_old",
        "[init] can't drop table color_labels_old\n");

    TRY_EXEC("CREATE UNIQUE INDEX `color_labels_idx` ON `color_labels` (imgid, color)",
        "[init] can't recreate color_labels_idx\n");

    // meta data
    TRY_EXEC("ALTER TABLE `meta_data` RENAME TO `meta_data_old`",
         "[init] can't rename meta_data\n");
    TRY_EXEC("CREATE TABLE `meta_data` (id integer, key integer, value varchar, "
      "FOREIGN KEY(id) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new meta_data table\n");

    TRY_EXEC("DELETE FROM `meta_data_old` WHERE id NOT IN (SELECT id FROM `images`)",
      "[init] can't delete orphaned meta_data elements\n");

    TRY_EXEC("INSERT INTO `meta_data` SELECT * FROM `meta_data_old`",
         "[init] can't copy back from meta_data\n");

    TRY_EXEC("DROP TABLE meta_data_old",
        "[init] can't drop table meta_data_old\n");

    TRY_EXEC("CREATE UNIQUE INDEX `metadata_index` ON `meta_data` (id, key, value)",
         "[init] can't recreate metadata_index\n");

    // selected images
    TRY_EXEC("ALTER TABLE `selected_images` RENAME TO `selected_images_old`",
         "[init] can't rename selected_images\n");
    TRY_EXEC("CREATE TABLE `selected_images` (imgid INTEGER PRIMARY KEY, "
      "FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new selected_images table\n");

    TRY_EXEC("DELETE FROM `selected_images_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
      "[init] can't delete orphaned selected_images elements\n");

    TRY_EXEC("INSERT INTO `selected_images` SELECT * FROM `selected_images_old`",
         "[init] can't copy back selected_images meta_data\n");

    TRY_EXEC("DROP TABLE selected_images_old",
        "[init] can't drop table selected_images_old\n");

    // module order
    TRY_EXEC("ALTER TABLE `module_order` RENAME TO `module_order_old`",
         "[init] can't rename module_order\n");
    TRY_EXEC("CREATE TABLE `module_order` (imgid INTEGER PRIMARY KEY, version INTEGER, iop_list VARCHAR, "
        "FOREIGN KEY(imgid) REFERENCES images(id) ON DELETE CASCADE ON UPDATE CASCADE)",
        "[init] can't create new module_order table\n");

    TRY_EXEC("DELETE FROM `module_order_old` WHERE imgid NOT IN (SELECT id FROM `images`)",
        "[init] can't delete orphaned module_order elements\n");

    TRY_EXEC("INSERT INTO `module_order` SELECT * FROM `module_order_old`",
         "[init] can't copy back module_order meta_data\n");

    TRY_EXEC("DROP TABLE module_order_old",
        "[init] can't drop table module_order_old\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 33;
  }
  else if(version == 33)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);

    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.images_datetime_taken_nc ON images (datetime_taken COLLATE NOCASE)",
             "[init] can't create images_datetime_taken\n");
    TRY_EXEC("CREATE INDEX IF NOT EXISTS main.metadata_index_key ON meta_data (key)",
             "[init] can't create metadata_index_key\n");

    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    new_version = 34;
  }
  else if(version == 34)
  {
    sqlite3_exec(db->handle, "PRAGMA foreign_keys = OFF", NULL, NULL, NULL);
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);

    TRY_EXEC("CREATE TABLE main.images_new (id INTEGER PRIMARY KEY AUTOINCREMENT, group_id INTEGER, film_id INTEGER, "
        "width INTEGER, height INTEGER, filename VARCHAR, maker VARCHAR, model VARCHAR, "
        "lens VARCHAR, exposure REAL, aperture REAL, iso REAL, focal_length REAL, "
        "focus_distance REAL, datetime_taken INTEGER, flags INTEGER, "
        "output_width INTEGER, output_height INTEGER, crop REAL, "
        "raw_parameters INTEGER, raw_denoise_threshold REAL, "
        "raw_auto_bright_threshold REAL, raw_black INTEGER, raw_maximum INTEGER, "
        "license VARCHAR, sha1sum CHAR(40), "
        "orientation INTEGER, histogram BLOB, lightmap BLOB, longitude REAL, "
        "latitude REAL, altitude REAL, color_matrix BLOB, colorspace INTEGER, version INTEGER, "
        "max_version INTEGER, write_timestamp INTEGER, history_end INTEGER, position INTEGER, "
        "aspect_ratio REAL, exposure_bias REAL, "
        "import_timestamp INTEGER, change_timestamp INTEGER, "
        "export_timestamp INTEGER, print_timestamp INTEGER, "
        "FOREIGN KEY(film_id) REFERENCES film_rolls(id) ON DELETE CASCADE ON UPDATE CASCADE, "
        "FOREIGN KEY(group_id) REFERENCES images(id) ON DELETE RESTRICT ON UPDATE CASCADE)",
        "[init] can't create new images table\n");

    TRY_EXEC("INSERT INTO `images_new` SELECT "
        "id, group_id, film_id, width, height, filename, maker, model, "
        "lens, exposure, aperture, iso, focal_length, focus_distance, NULL AS datetime_taken, flags, "
        "output_width, output_height, crop, raw_parameters, raw_denoise_threshold, raw_auto_bright_threshold, raw_black, raw_maximum, "
        "license, sha1sum, orientation, histogram, lightmap, longitude, latitude, altitude, color_matrix, colorspace, version, "
        "max_version, write_timestamp, history_end, position, aspect_ratio, exposure_bias, "
        "NULL AS import_timestamp, NULL AS change_timestamp, NULL AS export_timestamp, NULL AS print_timestamp "
        "FROM `images`",
        "[init] can't copy back from images\n");

    TRY_PREPARE(stmt, "SELECT id,"
                      " CASE WHEN datetime_taken = '' THEN NULL ELSE datetime_taken END,"
                      " CASE WHEN import_timestamp = -1 THEN NULL ELSE import_timestamp END,"
                      " CASE WHEN change_timestamp = -1 THEN NULL ELSE change_timestamp END,"
                      " CASE WHEN export_timestamp = -1 THEN NULL ELSE export_timestamp END,"
                      " CASE WHEN print_timestamp = -1 THEN NULL ELSE print_timestamp END "
                      "FROM `images`",
                "[init] can't get datetime from images\n");
    while(sqlite3_step(stmt) == SQLITE_ROW)
    {
      sqlite3_stmt *stmt2;
      sqlite3_prepare_v2(db->handle,
                         "UPDATE `images_new` SET"
                         " (datetime_taken, import_timestamp,"
                         "  change_timestamp, export_timestamp, print_timestamp) = "
                         " (?2, ?3, ?4, ?5, ?6) WHERE id = ?1",
                         -1, &stmt2, NULL);
      sqlite3_bind_int(stmt2, 1, sqlite3_column_int(stmt, 0));
      if(sqlite3_column_type(stmt, 1) != SQLITE_NULL)
      {
        GDateTime *gdt = dt_datetime_exif_to_gdatetime((const char *)sqlite3_column_text(stmt, 1), darktable.utc_tz);
        if(gdt)
        {
          sqlite3_bind_int64(stmt2, 2, dt_datetime_gdatetime_to_gtimespan(gdt));
          g_date_time_unref(gdt);
        }
      }
      for(int i = 0; i < 4; i++)
      {
        if(sqlite3_column_type(stmt, i + 2) != SQLITE_NULL)
        {
          GDateTime *gdt = g_date_time_new_from_unix_utc(sqlite3_column_int(stmt, i + 2));
          if(gdt)
          {
            sqlite3_bind_int64(stmt2, i + 3, dt_datetime_gdatetime_to_gtimespan(gdt));
            g_date_time_unref(gdt);
          }
        }
      }
      TRY_STEP(stmt2, SQLITE_DONE, "[init] can't update datetimes into images_new table\n");
      sqlite3_finalize(stmt2);
    }
    sqlite3_finalize(stmt);

    TRY_EXEC("DROP TABLE `images`", "[init] can't drop images table\n");
    // that's the way to keep the other tables foreign keys references valid
    TRY_EXEC("ALTER TABLE `images_new` RENAME TO `images`", "[init] can't rename images_new table to images");

    // pita: need to recreate indexes
    TRY_EXEC("CREATE INDEX `image_position_index` ON `images` (position)",
        "[init] can't add image_position_index\n");
    TRY_EXEC("CREATE INDEX `images_filename_index` ON `images` ( `filename`, `version` )",
        "[init] can't recreate images_filename_index\n");
    TRY_EXEC("CREATE INDEX `images_film_id_index` ON `images` ( `film_id`, `filename` )",
        "[init] can't recreate images_film_id_index\n");
    TRY_EXEC("CREATE INDEX `images_group_id_index` ON `images` ( `group_id`, `id` )",
        "[init] can't recreate images_group_id_index\n");
    TRY_EXEC("CREATE INDEX `images_latlong_index` ON `images` ( latitude DESC, longitude DESC )",
        "[init] can't add images_latlong_index\n");
    TRY_EXEC("CREATE INDEX `images_datetime_taken` ON images (datetime_taken)",
        "[init] can't create images_datetime_taken\n");

    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);
    sqlite3_exec(db->handle, "PRAGMA foreign_keys = ON", NULL, NULL, NULL);
    new_version = 35;
  }
  else if(version == 35)
  {
    TRY_EXEC("CREATE TABLE main.images_new (id INTEGER, filename VARCHAR, flags INTEGER)",
             "[init] can't create new images table\n");

    gchar *query = g_strdup_printf("INSERT INTO `images_new` "
                                   "SELECT id, filename, flags"
                                   " FROM images"
                                   " WHERE (flags & %d == 0)",
                                   DT_IMAGE_RAW | DT_IMAGE_LDR | DT_IMAGE_HDR);
    TRY_EXEC(query, "[init] can't copy back from images\n");

    TRY_PREPARE(stmt, "SELECT id, filename, flags FROM `images_new`",
                "[init] can't prepare selecting images flags\n");

    while(sqlite3_step(stmt) == SQLITE_ROW)
    {
      sqlite3_stmt *stmt2;
      sqlite3_prepare_v2(db->handle,
                         "UPDATE `images` SET"
                         " (flags) = "
                         " (?2) WHERE id = ?1",
                         -1, &stmt2, NULL);
      sqlite3_bind_int(stmt2, 1, sqlite3_column_int(stmt, 0));

      dt_image_flags_t flags = sqlite3_column_int(stmt, 2);
      gchar *ext = g_strrstr((const char *)sqlite3_column_text(stmt, 1), ".");
      flags |= dt_imageio_get_type_from_extension(ext);
      sqlite3_bind_int(stmt2, 2, flags);

      TRY_STEP(stmt2, SQLITE_DONE, "[init] can't update flags\n");
      sqlite3_finalize(stmt2);
    }
    sqlite3_finalize(stmt);

    TRY_EXEC("DROP TABLE `images_new`", "[init] can't drop temp images table\n");
    new_version = 36;
  }
  else
    new_version = version; // should be the fallback so that calling code sees that we are in an infinite loop

  // write the new version to db
  sqlite3_prepare_v2(db->handle, "INSERT OR REPLACE INTO main.db_info (key, value) VALUES ('version', ?1)", -1, &stmt,
                     NULL);
  sqlite3_bind_int(stmt, 1, new_version);
  sqlite3_step(stmt);
  sqlite3_finalize(stmt);

  return new_version;
}

/* do the real migration steps, returns the version the db was converted to */
static int _upgrade_data_schema_step(dt_database_t *db, int version)
{
  sqlite3_stmt *stmt;
  int new_version = version;
  if(version == CURRENT_DATABASE_VERSION_DATA)
    return version;
  else if(version == 0)
  {
    // this can't happen, we started with 1, but it's a good example how this function works
    // <do some magic to the db>
    new_version = 1; // the version we transformed the db to. this way it might be possible to roll back or
    // add fast paths
  }
  else if(version == 1)
  {
    // clang-format off
    // style_items:
    //    NO TRY_EXEC has the column could be there before version 1 (master build)
    //    TRY_EXEC("ALTER TABLE data.style_items ADD COLUMN iop_order REAL",
    //             "[init] can't add `iop_order' column to style_items table in database\n");
    sqlite3_exec(db->handle, "ALTER TABLE data.style_items ADD COLUMN iop_order REAL", NULL, NULL, NULL);
    // clang-format on
    sqlite3_stmt *sel_stmt = NULL;
    GList *prior_v1 = dt_ioppr_get_iop_order_list_version(DT_IOP_ORDER_LEGACY);
    // clang-format off
    // create a temp table with the previous priorities
    TRY_EXEC("CREATE TEMPORARY TABLE iop_order_tmp (iop_order REAL, operation VARCHAR(256))",
             "[init] can't create temporary table for updating `data.style_items'\n");
    // clang-format on
    // fill temp table with all operations up to this release
    // it will be used to create the pipe and update the iop_order on history
    for(GList *priorities = prior_v1; priorities; priorities = g_list_next(priorities))
    {
      dt_iop_order_entry_t *prior = (dt_iop_order_entry_t *)priorities->data;

      sqlite3_prepare_v2(
          db->handle,
          "INSERT INTO iop_order_tmp (iop_order, operation) VALUES (?1, ?2)",
          -1, &stmt, NULL);
      sqlite3_bind_double(stmt, 1, prior->o.iop_order_f);
      sqlite3_bind_text(stmt, 2, prior->operation, -1, SQLITE_TRANSIENT);
      TRY_STEP(stmt, SQLITE_DONE, "[init] can't insert default value in iop_order_tmp\n");
      sqlite3_finalize(stmt);
    }
    g_list_free_full(prior_v1, free);

    // do the same as for history
    // clang-format off
    TRY_EXEC("UPDATE data.style_items SET iop_order = ((("
        "SELECT MAX(multi_priority) FROM data.style_items style1 WHERE style1.styleid = data.style_items.styleid AND style1.operation = data.style_items.operation "
             ") + 1. - multi_priority) / 1000.) + "
             "IFNULL((SELECT iop_order FROM iop_order_tmp WHERE iop_order_tmp.operation = "
             "data.style_items.operation), -999999.) ",
             "[init] can't update iop_order in style_items table\n");

    TRY_PREPARE(sel_stmt, "SELECT DISTINCT operation FROM data.style_items WHERE iop_order <= 0 OR iop_order IS NULL",
                "[init] can't prepare selecting style_items iop_order\n");
    // clang-format on
    while(sqlite3_step(sel_stmt) == SQLITE_ROW)
    {
      const char *op_name = (const char *)sqlite3_column_text(sel_stmt, 0);
      printf("operation %s with no iop_order while upgrading style_items in database\n", op_name);
    }
    sqlite3_finalize(sel_stmt);
    // clang-format off
    TRY_EXEC("DROP TABLE iop_order_tmp", "[init] can't drop table `iop_order_tmp' from database\n");
    // clang-format on
    new_version = 2;
  }
  else if(version == 2)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);

    //    With sqlite above or equal to 3.25.0 RENAME COLUMN can be used instead of the following code
    //    TRY_EXEC("ALTER TABLE data.tags RENAME COLUMN description TO synonyms;",
    //             "[init] can't change tags column name from description to synonyms\n");
    // clang-format off
    TRY_EXEC("ALTER TABLE data.tags RENAME TO tmp_tags",  "[init] can't rename table tags\n");

    TRY_EXEC("CREATE TABLE data.tags (id INTEGER PRIMARY KEY, name VARCHAR, "
             "synonyms VARCHAR, flags INTEGER)",
             "[init] can't create new tags table\n");

    TRY_EXEC("INSERT INTO data.tags (id, name, synonyms, flags) SELECT id, name, description, flags "
             "FROM tmp_tags",
             "[init] can't populate tags table from tmp_tags\n");

    TRY_EXEC("DROP TABLE tmp_tags", "[init] can't delete table tmp_tags\n");

    TRY_EXEC("CREATE UNIQUE INDEX data.tags_name_idx ON tags (name)",
             "[init] can't create tags_name_idx on tags table\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 3;
  }
  else if(version == 3)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // create a temp table to invert all multi_priority
    TRY_EXEC("CREATE TEMPORARY TABLE m_prio (id INTEGER, operation VARCHAR(256), prio INTEGER)",
             "[init] can't create temporary table for updating `history and style_items'\n");

    TRY_EXEC("INSERT INTO m_prio SELECT styleid, operation, MAX(multi_priority)"
             " FROM data.style_items GROUP BY styleid, operation",
             "[init] can't populate m_prio\n");

    // update multi_priority for style items and history
    TRY_EXEC("UPDATE data.style_items SET multi_priority = "
             "(SELECT prio FROM m_prio "
             " WHERE data.style_items.operation = operation AND data.style_items.styleid = id)"
             " - data.style_items.multi_priority",
             "[init] can't update multi_priority for style_items\n");

    TRY_EXEC("DROP TABLE m_prio", "[init] can't drop table `m_prio' from database\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 4;
  }
  else if(version == 4)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format off
    // remove iop_order from style_item table
    TRY_EXEC("ALTER TABLE data.style_items RENAME TO s",
             "[init] can't rename style_items to s\n");
    TRY_EXEC("CREATE TABLE data.style_items (styleid INTEGER, num INTEGER, module INTEGER, "
             "operation VARCHAR(256), op_params BLOB, enabled INTEGER, "
             "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
             "[init] can't create style_items table'\n");
    TRY_EXEC("INSERT INTO data.style_items SELECT styleid, num, module, operation, op_params, enabled, "
             " blendop_params, blendop_version, multi_priority, multi_name "
             "FROM s",
             "[init] can't populate style_items table'\n");
    TRY_EXEC("DROP TABLE s",
             "[init] can't drop table s'\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 5;
  }
  else if(version == 5)
  {
    sqlite3_exec(db->handle, "BEGIN TRANSACTION", NULL, NULL, NULL);
    // clang-format of
    // make style.id a PRIMARY KEY and add iop_list
    TRY_EXEC("ALTER TABLE data.styles RENAME TO s",
             "[init] can't rename styles to s\n");
    TRY_EXEC("CREATE TABLE data.styles (id INTEGER PRIMARY KEY, name VARCHAR, description VARCHAR, iop_list VARCHAR)",
             "[init] can't create styles table\n");
    TRY_EXEC("INSERT INTO data.styles SELECT id, name, description, NULL FROM s",
             "[init] can't populate styles table\n");
    TRY_EXEC("DROP TABLE s",
             "[init] can't drop table s\n");

    TRY_EXEC("CREATE INDEX IF NOT EXISTS data.styles_name_index ON styles (name)",
             "[init] can't create styles_nmae_index\n");

    // make style_items.styleid index

    TRY_EXEC("CREATE INDEX IF NOT EXISTS data.style_items_styleid_index ON style_items (styleid)",
             "[init] can't create style_items_styleid_index\n");
    // clang-format on
    sqlite3_exec(db->handle, "COMMIT", NULL, NULL, NULL);

    new_version = 6;
  }
  else if(version == 6)
  {
    // clang-format off
    TRY_EXEC("CREATE TABLE data.locations "
             "(tagid INTEGER PRIMARY KEY, type INTEGER, longitude REAL, latitude REAL, "
             "delta1 REAL, delta2 REAL, FOREIGN KEY(tagid) REFERENCES tags(id))",
             "[init] can't create new locations table\n");
    // clang-format on
    new_version = 7;
  }
  else if(version == 7)
  {
    // clang-format off
    TRY_EXEC("ALTER TABLE data.locations ADD COLUMN ratio FLOAT DEFAULT 1",
             "[init] can't add column `ratio' column to locations table\n");
    // clang-format on
    new_version = 8;
  }
  else if(version == 8)
  {
    // clang-format off
    TRY_EXEC("ALTER TABLE data.locations ADD COLUMN polygons BLOB",
             "[init] can't add column `polygons' column to locations table\n");
    // clang-format on
    new_version = 9;
  }
  else
    new_version = version; // should be the fallback so that calling code sees that we are in an infinite loop

  // write the new version to db
  // clang-format off¨
  sqlite3_prepare_v2(db->handle, "INSERT OR REPLACE INTO data.db_info (key, value) VALUES ('version', ?1)", -1, &stmt,
                     NULL);
  // clang-format on
  sqlite3_bind_int(stmt, 1, new_version);
  sqlite3_step(stmt);
  sqlite3_finalize(stmt);

  return new_version;
}

#undef FINALIZE

#undef TRY_EXEC
#undef TRY_STEP
#undef TRY_PREPARE

/* upgrade library db from 'version' to CURRENT_DATABASE_VERSION_LIBRARY. don't touch this function but
 * _upgrade_library_schema_step() instead. */
static gboolean _upgrade_library_schema(dt_database_t *db, int version)
{
  while(version < CURRENT_DATABASE_VERSION_LIBRARY)
  {
    const int new_version = _upgrade_library_schema_step(db, version);
    if(new_version == version)
      return FALSE; // we don't know how to upgrade this db. probably a bug in _upgrade_library_schema_step
    else
      version = new_version;
  }
  return TRUE;
}

/* upgrade data db from 'version' to CURRENT_DATABASE_VERSION_DATA. don't touch this function but
 * _upgrade_data_schema_step() instead. */
static gboolean _upgrade_data_schema(dt_database_t *db, int version)
{
  while(version < CURRENT_DATABASE_VERSION_DATA)
  {
    const int new_version = _upgrade_data_schema_step(db, version);
    if(new_version == version)
      return FALSE; // we don't know how to upgrade this db. probably a bug in _upgrade_data_schema_step
    else
      version = new_version;
  }
  return TRUE;
}

/* create the current database schema and set the version in db_info accordingly */
static void _create_library_schema(dt_database_t *db)
{
  sqlite3_stmt *stmt;
  ////////////////////////////// db_info
  // clang-format off
  sqlite3_exec(db->handle, "CREATE TABLE main.db_info (key VARCHAR PRIMARY KEY, value VARCHAR)", NULL,
               NULL, NULL);
  sqlite3_prepare_v2(
      db->handle, "INSERT OR REPLACE INTO main.db_info (key, value) VALUES ('version', ?1)", -1, &stmt, NULL);
  // clang-format on
  sqlite3_bind_int(stmt, 1, CURRENT_DATABASE_VERSION_LIBRARY);
  sqlite3_step(stmt);
  sqlite3_finalize(stmt);
  ////////////////////////////// film_rolls
  // clang-format off
  sqlite3_exec(db->handle,
               "CREATE TABLE main.film_rolls "
               "(id INTEGER PRIMARY KEY, access_timestamp INTEGER, "
               //                        "folder VARCHAR(1024), external_drive VARCHAR(1024))", //
               //                        FIXME: make sure to bump CURRENT_DATABASE_VERSION_LIBRARY and add a
               //                        case to _upgrade_library_schema_step when adding this!
               "folder VARCHAR(1024) NOT NULL)",
               NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.film_rolls_folder_index ON film_rolls (folder)", NULL, NULL, NULL);
  ////////////////////////////// images
  sqlite3_exec(
      db->handle,
      "CREATE TABLE main.images (id INTEGER PRIMARY KEY AUTOINCREMENT, group_id INTEGER, film_id INTEGER, "
      "width INTEGER, height INTEGER, filename VARCHAR, maker VARCHAR, model VARCHAR, "
      "lens VARCHAR, exposure REAL, aperture REAL, iso REAL, focal_length REAL, "
      "focus_distance REAL, datetime_taken INTEGER, flags INTEGER, "
      "output_width INTEGER, output_height INTEGER, crop REAL, "
      "raw_parameters INTEGER, raw_denoise_threshold REAL, "
      "raw_auto_bright_threshold REAL, raw_black INTEGER, raw_maximum INTEGER, "
      "license VARCHAR, sha1sum CHAR(40), "
      "orientation INTEGER, histogram BLOB, lightmap BLOB, longitude REAL, "
      "latitude REAL, altitude REAL, color_matrix BLOB, colorspace INTEGER, version INTEGER, "
      "max_version INTEGER, write_timestamp INTEGER, history_end INTEGER, position INTEGER, "
      "aspect_ratio REAL, exposure_bias REAL, "
      "import_timestamp INTEGER DEFAULT -1, change_timestamp INTEGER DEFAULT -1, "
      "export_timestamp INTEGER DEFAULT -1, print_timestamp INTEGER DEFAULT -1, "
      "FOREIGN KEY(film_id) REFERENCES film_rolls(id) ON DELETE CASCADE ON UPDATE CASCADE, "
      "FOREIGN KEY(group_id) REFERENCES images(id) ON DELETE RESTRICT ON UPDATE CASCADE)",
      NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.images_group_id_index ON images (group_id, id)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.images_film_id_index ON images (film_id, filename)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.images_filename_index ON images (filename, version)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.image_position_index ON images (position)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.images_datetime_taken_nc ON images (datetime_taken)", NULL, NULL, NULL);

  ////////////////////////////// selected_images
  sqlite3_exec(db->handle, "CREATE TABLE main.selected_images (imgid INTEGER PRIMARY KEY)", NULL, NULL, NULL);
  ////////////////////////////// history
  sqlite3_exec(
      db->handle,
      "CREATE TABLE main.history (imgid INTEGER, num INTEGER, module INTEGER, "
      "operation VARCHAR(256), op_params BLOB, enabled INTEGER, "
      "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256), "
      "FOREIGN KEY(imgid) REFERENCES images(id) ON UPDATE CASCADE ON DELETE CASCADE)",
      NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.history_imgid_op_index ON history (imgid, operation)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.history_imgid_num_index ON history (imgid, num DESC)", NULL, NULL, NULL);
  ////////////////////////////// masks history
  sqlite3_exec(db->handle,
               "CREATE TABLE main.masks_history (imgid INTEGER, num INTEGER, formid INTEGER, form INTEGER, name VARCHAR(256), "
               "version INTEGER, points BLOB, points_count INTEGER, source BLOB, "
                "FOREIGN KEY(imgid) REFERENCES images(id) ON UPDATE CASCADE ON DELETE CASCADE)",
                 NULL, NULL, NULL);

  sqlite3_exec(db->handle,
      "CREATE INDEX main.masks_history_imgid_index ON masks_history (imgid, num)",
      NULL, NULL, NULL);

  sqlite3_exec(db->handle, "CREATE INDEX main.images_latlong_index ON images (latitude DESC, longitude DESC)",
      NULL, NULL, NULL);

  ////////////////////////////// tagged_images
  sqlite3_exec(db->handle, "CREATE TABLE main.tagged_images (imgid INTEGER, tagid INTEGER, position INTEGER, "
                           "PRIMARY KEY (imgid, tagid),"
                           "FOREIGN KEY(imgid) REFERENCES images(id) ON UPDATE CASCADE ON DELETE CASCADE)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.tagged_images_tagid_index ON tagged_images (tagid)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.tagged_images_position_index ON tagged_images (position)", NULL, NULL, NULL);
  ////////////////////////////// color_labels
  sqlite3_exec(db->handle, "CREATE TABLE main.color_labels (imgid INTEGER, color INTEGER)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE UNIQUE INDEX main.color_labels_idx ON color_labels (imgid, color)", NULL, NULL,
               NULL);
  ////////////////////////////// meta_data
  sqlite3_exec(db->handle, "CREATE TABLE main.meta_data (id INTEGER, key INTEGER, value VARCHAR)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE UNIQUE INDEX main.metadata_index ON meta_data (id, key, value)", NULL, NULL, NULL);

  sqlite3_exec(db->handle, "CREATE INDEX main.metadata_index_key ON meta_data (key)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE TABLE main.module_order (imgid INTEGER PRIMARY KEY, version INTEGER, iop_list VARCHAR)",
               NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE TABLE main.history_hash (imgid INTEGER PRIMARY KEY, "
               "basic_hash BLOB, auto_hash BLOB, current_hash BLOB, mipmap_hash BLOB, "
               "FOREIGN KEY(imgid) REFERENCES images(id) ON UPDATE CASCADE ON DELETE CASCADE)",
               NULL, NULL, NULL);

  // v34
  sqlite3_exec(db->handle, "CREATE INDEX main.images_datetime_taken_nc ON images (datetime_taken COLLATE NOCASE)",
               NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX main.metadata_index_key ON meta_data (key)", NULL, NULL, NULL);
  // clang-format on
}

/* create the current database schema and set the version in db_info accordingly */
static void _create_data_schema(dt_database_t *db)
{
  sqlite3_stmt *stmt;
  // clang-format off
  ////////////////////////////// db_info
  sqlite3_exec(db->handle, "CREATE TABLE data.db_info (key VARCHAR PRIMARY KEY, value VARCHAR)", NULL,
               NULL, NULL);
  sqlite3_prepare_v2(
        db->handle, "INSERT OR REPLACE INTO data.db_info (key, value) VALUES ('version', ?1)", -1, &stmt, NULL);
  sqlite3_bind_int(stmt, 1, CURRENT_DATABASE_VERSION_DATA);
  sqlite3_step(stmt);
  sqlite3_finalize(stmt);
  ////////////////////////////// tags
  sqlite3_exec(db->handle, "CREATE TABLE data.tags (id INTEGER PRIMARY KEY, name VARCHAR, "
                           "synonyms VARCHAR, flags INTEGER)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE UNIQUE INDEX data.tags_name_idx ON tags (name)", NULL, NULL, NULL);
  ////////////////////////////// styles
  sqlite3_exec(db->handle, "CREATE TABLE data.styles (id INTEGER PRIMARY KEY, name VARCHAR, description VARCHAR, iop_list VARCHAR)",
                        NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE INDEX data.styles_name_index ON styles (name)", NULL, NULL, NULL);
  ////////////////////////////// style_items
  sqlite3_exec(
      db->handle,
      "CREATE TABLE data.style_items (styleid INTEGER, num INTEGER, module INTEGER, "
      "operation VARCHAR(256), op_params BLOB, enabled INTEGER, "
      "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
      NULL, NULL, NULL);
  sqlite3_exec(
      db->handle,
      "CREATE INDEX IF NOT EXISTS data.style_items_styleid_index ON style_items (styleid)",
      NULL, NULL, NULL);
  ////////////////////////////// presets
  sqlite3_exec(db->handle, "CREATE TABLE data.presets (name VARCHAR, description VARCHAR, operation "
                           "VARCHAR, op_version INTEGER, op_params BLOB, "
                           "enabled INTEGER, blendop_params BLOB, blendop_version INTEGER, "
                           "multi_priority INTEGER, multi_name VARCHAR(256), "
                           "model VARCHAR, maker VARCHAR, lens VARCHAR, iso_min REAL, iso_max REAL, "
                           "exposure_min REAL, exposure_max REAL, "
                           "aperture_min REAL, aperture_max REAL, focal_length_min REAL, "
                           "focal_length_max REAL, writeprotect INTEGER, "
                           "autoapply INTEGER, filter INTEGER, def INTEGER, format INTEGER)",
               NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE UNIQUE INDEX data.presets_idx ON presets (name, operation, op_version)",
               NULL, NULL, NULL);
  ////////////////////////////// (map) locations
  sqlite3_exec(db->handle, "CREATE TABLE data.locations (tagid INTEGER PRIMARY KEY, "
               "type INTEGER, longitude REAL, latitude REAL, delta1 REAL, delta2 REAL, ratio FLOAT, polygons BLOB, "
               "FOREIGN KEY(tagid) REFERENCES tags(id))", NULL, NULL, NULL);
  // clang-format on
}

// create the in-memory tables
// temporary stuff for some ops, need this for some reason with newer sqlite3:
static void _create_memory_schema(dt_database_t *db)
{
  // clang-format off
  sqlite3_exec(db->handle, "CREATE TABLE memory.color_labels_temp (imgid INTEGER PRIMARY KEY)", NULL, NULL, NULL);
  sqlite3_exec(
      db->handle,
      "CREATE TABLE memory.collected_images (rowid INTEGER PRIMARY KEY AUTOINCREMENT, imgid INTEGER)", NULL,
      NULL, NULL);
  sqlite3_exec(db->handle, "CREATE TABLE memory.tmp_selection (imgid INTEGER PRIMARY KEY)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE TABLE memory.taglist "
                           "(tmpid INTEGER PRIMARY KEY, id INTEGER UNIQUE ON CONFLICT IGNORE, "
                           "count INTEGER DEFAULT 0, count2 INTEGER DEFAULT 0)",
               NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE TABLE memory.similar_tags (tagid INTEGER PRIMARY KEY)", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "CREATE TABLE memory.darktable_tags (tagid INTEGER PRIMARY KEY)", NULL, NULL, NULL);
  sqlite3_exec(
      db->handle,
      "CREATE TABLE memory.history (imgid INTEGER, num INTEGER, module INTEGER, "
      "operation VARCHAR(256) UNIQUE ON CONFLICT REPLACE, op_params BLOB, enabled INTEGER, "
      "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
      NULL, NULL, NULL);
  sqlite3_exec(
      db->handle,
      "CREATE TABLE memory.undo_history (id INTEGER, imgid INTEGER, num INTEGER, module INTEGER, "
      "operation VARCHAR(256), op_params BLOB, enabled INTEGER, "
      "blendop_params BLOB, blendop_version INTEGER, multi_priority INTEGER, multi_name VARCHAR(256))",
      NULL, NULL, NULL);
  sqlite3_exec(
      db->handle,
      "CREATE TABLE memory.undo_masks_history (id INTEGER, imgid INTEGER, num INTEGER, formid INTEGER,"
      " form INTEGER, name VARCHAR(256), version INTEGER, points BLOB, points_count INTEGER, source BLOB)",
      NULL, NULL, NULL);
  sqlite3_exec(
      db->handle,
      "CREATE TABLE memory.undo_module_order (id INTEGER, imgid INTEGER, version INTEGER, iop_list VARCHAR)",
      NULL, NULL, NULL);
  sqlite3_exec(db->handle,
      "CREATE TABLE memory.darktable_iop_names (operation VARCHAR(256) PRIMARY KEY, name VARCHAR(256))",
      NULL, NULL, NULL);
  sqlite3_exec(db->handle,
      "CREATE TABLE memory.film_folder (id INTEGER PRIMARY KEY, status INTEGER)",
      NULL, NULL, NULL);
  // clang-format on
}

static void _sanitize_db(dt_database_t *db)
{
  sqlite3_stmt *stmt, *innerstmt;
  // clang-format off
  /* first let's get rid of non-utf8 tags. */
  sqlite3_prepare_v2(db->handle, "SELECT id, name FROM data.tags", -1, &stmt, NULL);
  sqlite3_prepare_v2(db->handle, "UPDATE data.tags SET name = ?1 WHERE id = ?2", -1, &innerstmt, NULL);
  // clang-format on
  while(sqlite3_step(stmt) == SQLITE_ROW)
  {
    const int id = sqlite3_column_int(stmt, 0);
    const char *tag = (const char *)sqlite3_column_text(stmt, 1);

    if(!g_utf8_validate(tag, -1, NULL))
    {
      gchar *new_tag = dt_util_foo_to_utf8(tag);
      fprintf(stderr, "[init]: tag `%s' is not valid utf8, replacing it with `%s'\n", tag, new_tag);
      if(tag)
      {
        sqlite3_bind_text(innerstmt, 1, new_tag, -1, SQLITE_TRANSIENT);
        sqlite3_bind_int(innerstmt, 2, id);
        sqlite3_step(innerstmt);
        sqlite3_reset(innerstmt);
        sqlite3_clear_bindings(innerstmt);
        g_free(new_tag);
      }
    }
  }
  sqlite3_finalize(stmt);
  sqlite3_finalize(innerstmt);
  // clang-format off
  // make sure film_roll folders don't end in "/", that will result in empty entries in the collect module
  sqlite3_exec(db->handle,
               "UPDATE main.film_rolls SET folder = substr(folder, 1, length(folder) - 1) WHERE folder LIKE '%/'",
               NULL, NULL, NULL);
  // clang-format on
}

// in library we keep the names of the tags used in tagged_images. however, using that table at runtime results
// in some overhead not necessary so instead we just use the used_tags table to update tagged_images on startup
#define TRY_EXEC(_query, _message)                                                 \
  do                                                                               \
  {                                                                                \
    if(sqlite3_exec(db->handle, _query, NULL, NULL, NULL) != SQLITE_OK)            \
    {                                                                              \
      fprintf(stderr, _message);                                                   \
      fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));                \
      FINALIZE;                                                                    \
      sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);          \
      return FALSE;                                                                \
    }                                                                              \
  } while(0)

#define TRY_STEP(_stmt, _expected, _message)                                       \
  do                                                                               \
  {                                                                                \
    if(sqlite3_step(_stmt) != _expected)                                           \
    {                                                                              \
      fprintf(stderr, _message);                                                   \
      fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));                \
      FINALIZE;                                                                    \
      sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);          \
      return FALSE;                                                                \
    }                                                                              \
  } while(0)

#define TRY_PREPARE(_stmt, _query, _message)                                       \
  do                                                                               \
  {                                                                                \
    if(sqlite3_prepare_v2(db->handle, _query, -1, &_stmt, NULL) != SQLITE_OK)      \
    {                                                                              \
      fprintf(stderr, _message);                                                   \
      fprintf(stderr, "[init]   %s\n", sqlite3_errmsg(db->handle));                \
      FINALIZE;                                                                    \
      sqlite3_exec(db->handle, "ROLLBACK TRANSACTION", NULL, NULL, NULL);          \
      return FALSE;                                                                \
    }                                                                              \
  } while(0)

#define FINALIZE                                                                   \
  do                                                                               \
  {                                                                                \
    sqlite3_finalize(stmt); stmt = NULL; /* NULL so that finalize becomes a NOP */ \
  } while(0)

#undef TRY_EXEC
#undef TRY_STEP
#undef TRY_PREPARE
#undef FINALIZE

void dt_database_show_error(const dt_database_t *db)
{
  if(!db->lock_acquired)
  {
    char lck_pathname[1024];
    snprintf(lck_pathname, sizeof(lck_pathname), "%s.lock", db->error_dbfilename);
    char *lck_dirname = g_strdup(lck_pathname);
    *g_strrstr(lck_dirname, "/") = '\0';
    // clang-format off
    char *label_text = g_markup_printf_escaped(
        _("\n"
          "  Sorry, darktable could not be started (database is locked)\n"
          "\n"
          "  How to solve this problem?\n"
          "\n"
          "  1 - If another darktable instance is already open, \n"
          "      click cancel and either use that instance or close it before attempting to rerun darktable \n"
          "      (process ID <i><b>%d</b></i> created the database locks)\n"
          "\n"
          "  2 - If you can't find a running instance of darktable, try restarting your session or your computer. \n"
          "      This will close all running programs and hopefully close the databases correctly. \n"
          "\n"
          "  3 - If you have done this or are certain that no other instances of darktable are running, \n"
          "      this probably means that the last instance was ended abnormally. \n"
          "      Click on the \"delete database lock files\" button to remove the files <i>data.db.lock</i> and <i>library.db.lock</i>.  \n"
          "\n\n"
          "      <i><u>Caution!</u> Do not delete these files without first undertaking the above checks, \n"
          "      otherwise you risk generating serious inconsistencies in your database.</i>\n"),
      db->error_other_pid);
    // clang-format on

    gboolean delete_lockfiles = dt_gui_show_standalone_yes_no_dialog(_("error starting darktable"),
                                        label_text, _("cancel"), _("delete database lock files"));

    if(delete_lockfiles)
    {
      gboolean really_delete_lockfiles =
        dt_gui_show_standalone_yes_no_dialog
        (_("are you sure?"),
         _("\ndo you really want to delete the lock files?\n"), _("no"), _("yes"));
      if(really_delete_lockfiles)
      {
        int status = 0;

        char *lck_filename = g_strconcat(lck_dirname, "/data.db.lock", NULL);
        if(g_access(lck_filename, F_OK) != -1)
          status += remove(lck_filename);

        lck_filename = g_strconcat(lck_dirname, "/library.db.lock", NULL);
        if(g_access(lck_filename, F_OK) != -1)
          status += remove(lck_filename);
        g_free(lck_filename);

        if(status==0)
          dt_gui_show_standalone_yes_no_dialog(_("done"),
                                        _("\nsuccessfully deleted the lock files.\nyou can now restart darktable\n"),
                                        _("ok"), NULL);
        else
          dt_gui_show_standalone_yes_no_dialog
            (_("error"), g_markup_printf_escaped(
              _("\nat least one file could not be removed.\n"
                "you may try to manually delete the files <i>data.db.lock</i> and <i>library.db.lock</i>\n"
                "in folder <a href=\"file:///%s\">%s</a>.\n"), lck_dirname, lck_dirname),
             _("ok"), NULL);
      }
    }

    g_free(lck_dirname);
    g_free(label_text);
  }

  g_free(db->error_message);
  g_free(db->error_dbfilename);
  ((dt_database_t *)db)->error_other_pid = 0;
  ((dt_database_t *)db)->error_message = NULL;
  ((dt_database_t *)db)->error_dbfilename = NULL;
}

static gboolean pid_is_alive(int pid)
{
  gboolean pid_is_alive;

#ifdef _WIN32
  pid_is_alive = FALSE;
  HANDLE h = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE, pid);
  if(h)
  {
    wchar_t wfilename[MAX_PATH];
    long unsigned int n_filename = sizeof(wfilename);
    int ret = QueryFullProcessImageNameW(h, 0, wfilename, &n_filename);
    char *filename = g_utf16_to_utf8(wfilename, -1, NULL, NULL, NULL);
    if(ret && n_filename > 0 && filename && g_str_has_suffix(filename, "darktable.exe"))
      pid_is_alive = TRUE;
    g_free(filename);
    CloseHandle(h);
  }
#else
  pid_is_alive = !((kill(pid, 0) == -1) && errno == ESRCH);

#ifdef __linux__
  // If this is Linux, we can query /proc to see if the pid is
  // actually a darktable instance.
  if(pid_is_alive)
  {
    gchar *contents;
    gsize length;
    gchar filename[64];
    snprintf(filename, sizeof(filename), "/proc/%d/cmdline", pid);

    if(g_file_get_contents("", &contents, &length, NULL))
    {
      if(strstr(contents, "darktable") == NULL)
      {
        pid_is_alive = FALSE;
      }
      g_free(contents);
    }
  }
#endif

#endif

  return pid_is_alive;
}

static gboolean _lock_single_database(dt_database_t *db, const char *dbfilename, char **lockfile)
{
  gboolean lock_acquired = FALSE;
  mode_t old_mode;
  int lock_tries = 0;
  gchar *pid = g_strdup_printf("%d", getpid());

  if(!strcmp(dbfilename, ":memory:"))
  {
    lock_acquired = TRUE;
  }
  else
  {
    *lockfile = g_strconcat(dbfilename, ".lock", NULL);
lock_again:
    lock_tries++;
    old_mode = umask(0);
    int fd = g_open(*lockfile, O_RDWR | O_CREAT | O_EXCL, 0666);
    umask(old_mode);

    if(fd != -1) // the lockfile was successfully created - write our PID into it
    {
      if(write(fd, pid, strlen(pid) + 1) > -1) lock_acquired = TRUE;
      close(fd);
    }
    else // the lockfile already exists - see if it's a stale one left over from a crashed instance
    {
      char buf[64];
      memset(buf, 0, sizeof(buf));
      fd = g_open(*lockfile, O_RDWR | O_CREAT, 0666);
      if(fd != -1)
      {
        int foo;
        if((foo = read(fd, buf, sizeof(buf) - 1)) > 0)
        {
          db->error_other_pid = atoi(buf);
          if(!pid_is_alive(db->error_other_pid))
          {
            // the other process seems to no longer exist. unlink the .lock file and try again
            g_unlink(*lockfile);
            if(lock_tries < 5)
            {
              close(fd);
              goto lock_again;
            }
          }
          else
          {
            fprintf(
              stderr,
              "[init] the database lock file contains a pid that seems to be alive in your system: %d\n",
              db->error_other_pid);
            db->error_message = g_strdup_printf(_("the database lock file contains a pid that seems to be alive in your system: %d"), db->error_other_pid);
          }
        }
        else
        {
          fprintf(stderr, "[init] the database lock file seems to be empty\n");
          db->error_message = g_strdup_printf(_("the database lock file seems to be empty"));
        }
        close(fd);
      }
      else
      {
        int err = errno;
        fprintf(stderr, "[init] error opening the database lock file for reading: %s\n", strerror(err));
        db->error_message = g_strdup_printf(_("error opening the database lock file for reading: %s"), strerror(err));
      }
    }
  }

  g_free(pid);

  if(db->error_message)
    db->error_dbfilename = g_strdup(dbfilename);

  return lock_acquired;
}

static gboolean _lock_databases(dt_database_t *db)
{
  if(!_lock_single_database(db, db->dbfilename_data, &db->lockfile_data))
    return FALSE;
  if(!_lock_single_database(db, db->dbfilename_library, &db->lockfile_library))
  {
    // unlock data.db to not leave a stale lock file around
    g_unlink(db->lockfile_data);
    return FALSE;
  }
  return TRUE;
}

void ask_for_upgrade(const gchar *dbname, const gboolean has_gui)
{
  // if there's no gui just leave
  if(!has_gui)
  {
    fprintf(stderr, "[init] database `%s' is out-of-date. aborting.\n", dbname);
    exit(1);
  }

  // the database has to be upgraded, let's ask user

  char *label_text = g_markup_printf_escaped(_("the database schema has to be upgraded for\n"
                                               "\n"
                                               "<span style='italic'>%s</span>\n"
                                               "\nthis might take a long time in case of a large database\n\n"
                                               "do you want to proceed or quit now to do a backup\n"),
                                               dbname);

  gboolean shall_we_update_the_db =
    dt_gui_show_standalone_yes_no_dialog(_("darktable - schema migration"), label_text,
                                         _("close darktable"), _("upgrade database"));

  g_free(label_text);

  // if no upgrade, we exit now, nothing we can do more
  if(!shall_we_update_the_db)
  {
    fprintf(stderr, "[init] we shall not update the database, aborting.\n");
    exit(1);
  }
}

void dt_database_backup(const char *filename)
{
  char *version = g_strdup(darktable_package_version);
  int k = 0;
  // get plain version (no commit id)
  while(version[k])
  {
    if((version[k] < '0' || version[k] > '9') && (version[k] != '.'))
    {
      version[k] = '\0';
      break;
    }
    k++;
  }

  gchar *backup = g_strdup_printf("%s-pre-%s", filename, version);

  GError *gerror = NULL;
  if(!g_file_test(backup, G_FILE_TEST_EXISTS))
  {
    GFile *src = g_file_new_for_path(filename);
    GFile *dest = g_file_new_for_path(backup);
    gboolean copy_status = TRUE;
    if(g_file_test(filename, G_FILE_TEST_EXISTS))
    {
      copy_status = g_file_copy(src, dest, G_FILE_COPY_NONE, NULL, NULL, NULL, &gerror);
      if(copy_status) copy_status = g_chmod(backup, S_IRUSR) == 0;
    }
    else
    {
      // there is nothing to backup, create an empty file to prevent further backup attempts
      int fd = g_open(backup, O_CREAT, S_IRUSR);
      if(fd < 0 || !g_close(fd, &gerror)) copy_status = FALSE;
    }
    if(!copy_status) fprintf(stderr, "[backup failed] %s -> %s\n", filename, backup);

    g_object_unref(src);
    g_object_unref(dest);
  }

  g_free(version);
  g_free(backup);
}

int _get_pragma_int_val(sqlite3 *db, const char* pragma)
{
  gchar* query= g_strdup_printf("PRAGMA %s", pragma);
  int val = -1;
  sqlite3_stmt *stmt;
  const int rc = sqlite3_prepare_v2(db, query,-1, &stmt, NULL);
  if(rc == SQLITE_OK && sqlite3_step(stmt) == SQLITE_ROW)
  {
    val = sqlite3_column_int(stmt, 0);
  }
  sqlite3_finalize(stmt);
  g_free(query);

  return val;
}

gchar* _get_pragma_string_val(sqlite3 *db, const char* pragma)
{
  gchar* query= g_strdup_printf("PRAGMA %s", pragma);
  sqlite3_stmt *stmt;
  gchar* val = NULL;
  const int rc = sqlite3_prepare_v2(db, query,-1, &stmt, NULL);
  if(rc == SQLITE_OK && sqlite3_step(stmt) == SQLITE_ROW)
  {
    val = g_strdup((const char *)sqlite3_column_text(stmt, 0));
    while(sqlite3_step(stmt) == SQLITE_ROW)
    {
      gchar* cur_val = g_strdup((const char *)sqlite3_column_text(stmt, 0));
      gchar* tmp_val = g_strdup(val);
      g_free(val);
      val = g_strconcat(tmp_val, "\n", cur_val, NULL);
      g_free(cur_val);
      g_free(tmp_val);
    }
  }
  sqlite3_finalize(stmt);
  g_free(query);
  return val;
}

dt_database_t *dt_database_init(const char *alternative, const gboolean load_data, const gboolean has_gui)
{
  /*  set the threading mode to Serialized */
  sqlite3_config(SQLITE_CONFIG_SERIALIZED);

  sqlite3_initialize();

start:
  if(alternative == NULL)
  {
    /* migrate default database location to new default */
    _database_migrate_to_xdg_structure();
  }

  /* delete old mipmaps files */
  _database_delete_mipmaps_files();

  /* lets construct the db filename  */
  gchar *dbname = NULL;
  gchar dbfilename_library[PATH_MAX] = { 0 };
  gchar datadir[PATH_MAX] = { 0 };

  dt_loc_get_user_config_dir(datadir, sizeof(datadir));

  if(alternative == NULL)
  {
    dbname = dt_conf_get_string("database");
    if(!dbname)
      snprintf(dbfilename_library, sizeof(dbfilename_library), "%s/library.db", datadir);
    else if(!strcmp(dbname, ":memory:"))
      g_strlcpy(dbfilename_library, dbname, sizeof(dbfilename_library));
    else if(dbname[0] != '/')
      snprintf(dbfilename_library, sizeof(dbfilename_library), "%s/%s", datadir, dbname);
    else
      g_strlcpy(dbfilename_library, dbname, sizeof(dbfilename_library));
  }
  else
  {
    g_strlcpy(dbfilename_library, alternative, sizeof(dbfilename_library));

    GFile *galternative = g_file_new_for_path(alternative);
    dbname = g_file_get_basename(galternative);
    g_object_unref(galternative);
  }

  /* we also need a 2nd db with permanent data like presets, styles and tags */
  char dbfilename_data[PATH_MAX] = { 0 };
  if(load_data)
    snprintf(dbfilename_data, sizeof(dbfilename_data), "%s/data.db", datadir);
  else
    snprintf(dbfilename_data, sizeof(dbfilename_data), ":memory:");

  /* create database */
  dt_database_t *db = (dt_database_t *)g_malloc0(sizeof(dt_database_t));
  db->dbfilename_data = g_strdup(dbfilename_data);
  db->dbfilename_library = g_strdup(dbfilename_library);

  dt_atomic_set_int(&_trxid, 0);

  /* make sure the folder exists. this might not be the case for new databases */
  /* also check if a database backup is needed */
  if(g_strcmp0(dbfilename_data, ":memory:"))
  {
    char *data_path = g_path_get_dirname(dbfilename_data);
    g_mkdir_with_parents(data_path, 0750);
    g_free(data_path);
    dt_database_backup(dbfilename_data);
  }
  if(g_strcmp0(dbfilename_library, ":memory:"))
  {
    char *library_path = g_path_get_dirname(dbfilename_library);
    g_mkdir_with_parents(library_path, 0750);
    g_free(library_path);
    dt_database_backup(dbfilename_library);
  }

  dt_print(DT_DEBUG_SQL, "[init sql] library: %s, data: %s\n", dbfilename_library, dbfilename_data);

  /* having more than one instance of darktable using the same database is a bad idea */
  /* try to get locks for the databases */
  db->lock_acquired = _lock_databases(db);

  if(!db->lock_acquired)
  {
    fprintf(stderr, "[init] database is locked, probably another process is already using it\n");
    g_free(dbname);
    return db;
  }


  /* opening / creating database */
  if(sqlite3_open(db->dbfilename_library, &db->handle))
  {
    fprintf(stderr, "[init] could not find database ");
    if(dbname)
      fprintf(stderr, "`%s'!\n", dbname);
    else
      fprintf(stderr, "\n");
    fprintf(stderr, "[init] maybe your %s/darktablerc is corrupt?\n", datadir);
    dt_loc_get_datadir(dbfilename_library, sizeof(dbfilename_library));
    fprintf(stderr, "[init] try `cp %s/darktablerc %s/darktablerc'\n", dbfilename_library, datadir);
    sqlite3_close(db->handle);
    g_free(dbname);
    g_free(db->lockfile_data);
    g_free(db->dbfilename_data);
    g_free(db->lockfile_library);
    g_free(db->dbfilename_library);
    g_free(db);
    return NULL;
  }

  /* attach a memory database to db connection for use with temporary tables
     used during instance life time, which is discarded on exit.
  */
  sqlite3_exec(db->handle, "attach database ':memory:' as memory", NULL, NULL, NULL);

  // attach the data database which contains presets, styles, tags and similar things not tied to single images
  sqlite3_stmt *stmt;
  gboolean have_data_db = load_data && g_file_test(dbfilename_data, G_FILE_TEST_EXISTS);
  int rc = sqlite3_prepare_v2(db->handle, "ATTACH DATABASE ?1 AS data", -1, &stmt, NULL);
  sqlite3_bind_text(stmt, 1, dbfilename_data, -1, SQLITE_TRANSIENT);
  if(rc != SQLITE_OK || sqlite3_step(stmt) != SQLITE_DONE)
  {
    sqlite3_finalize(stmt);
    fprintf(stderr, "[init] database `%s' couldn't be opened. aborting\n", dbfilename_data);
    dt_database_destroy(db);
    db = NULL;
    goto error;
  }
  sqlite3_finalize(stmt);

  // some sqlite3 config
  sqlite3_exec(db->handle, "PRAGMA synchronous = OFF", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "PRAGMA journal_mode = MEMORY", NULL, NULL, NULL);
  sqlite3_exec(db->handle, "PRAGMA page_size = 32768", NULL, NULL, NULL);

  // WARNING: the foreign_keys pragma must not be used, the integrity of the
  // database rely on it.
  sqlite3_exec(db->handle, "PRAGMA foreign_keys = ON", NULL, NULL, NULL);

  /* now that we got functional databases that are locked for us we can make sure that the schema is set up */

  // first we update the data database to the latest version so that we can potentially move data from the library
  // over when updating that one
  if(!have_data_db)
  {
    _create_data_schema(db); // a brand new db it seems
  }
  else
  {
    gchar* data_status = _get_pragma_string_val(db->handle, "data.quick_check");
    rc = sqlite3_prepare_v2(db->handle, "select value from data.db_info where key = 'version'", -1, &stmt, NULL);
    if(!g_strcmp0(data_status, "ok") && rc == SQLITE_OK && sqlite3_step(stmt) == SQLITE_ROW)
    {
      g_free(data_status); // status is OK and we don't need to care :)
      // compare the version of the db with what is current for this executable
      const int db_version = sqlite3_column_int(stmt, 0);
      sqlite3_finalize(stmt);
      if(db_version < CURRENT_DATABASE_VERSION_DATA)
      {
        ask_for_upgrade(dbfilename_data, has_gui);

        // older: upgrade
        if(!_upgrade_data_schema(db, db_version))
        {
          // we couldn't upgrade the db for some reason. bail out.
          fprintf(stderr, "[init] database `%s' couldn't be upgraded from version %d to %d. aborting\n",
                  dbfilename_data, db_version, CURRENT_DATABASE_VERSION_DATA);
          dt_database_destroy(db);
          db = NULL;
          goto error;
        }

        // upgrade was successfull, time for some housekeeping
        sqlite3_exec(db->handle, "VACUUM data", NULL, NULL, NULL);
        sqlite3_exec(db->handle, "ANALYZE data", NULL, NULL, NULL);

      }
      else if(db_version > CURRENT_DATABASE_VERSION_DATA)
      {
        // newer: bail out
        fprintf(stderr, "[init] database version of `%s' is too new for this build of darktable. aborting\n",
                dbfilename_data);
        dt_database_destroy(db);
        db = NULL;
        goto error;
      }
      // else: the current version, do nothing
    }
    else
    {
      // oh, bad situation. the database is corrupt and can't be read!
      // we inform the user here and let him decide what to do: exit or delete and try again.

      gchar* quick_check_text = NULL;
      if(g_strcmp0(data_status, "ok")) // data_status is not ok
      {
        quick_check_text = g_strdup_printf(_("quick_check said:\n"
                                            "%s \n"), data_status);
      }
      else
      {
        quick_check_text = g_strdup(""); // a trick;
      }

      gchar *data_snap = dt_database_get_most_recent_snap(dbfilename_data);

      GtkWidget *dialog;
      GtkDialogFlags dflags = GTK_DIALOG_MODAL | GTK_DIALOG_DESTROY_WITH_PARENT;

      const char* label_options = NULL;

      if(data_snap)
      {
        dialog = gtk_dialog_new_with_buttons(_("darktable - error opening database"),
                                            NULL,
                                            dflags,
                                            _("close darktable"),
                                            GTK_RESPONSE_CLOSE,
                                            _("attempt restore"),
                                            GTK_RESPONSE_ACCEPT,
                                            _("delete database"),
                                            GTK_RESPONSE_REJECT,
                                            NULL);
        gtk_dialog_set_default_response(GTK_DIALOG(dialog), GTK_RESPONSE_ACCEPT);
        label_options = _("do you want to close darktable now to manually restore\n"
                          "the database from a backup, attempt an automatic restore\n"
                          "from the most recent snapshot or delete the corrupted database\n"
                          "and start with a new one?");
      }
      else
      {
        dialog = gtk_dialog_new_with_buttons(_("darktable - error opening database"),
                                            NULL,
                                            dflags,
                                            _("close darktable"),
                                            GTK_RESPONSE_CLOSE,
                                            _("delete database"),
                                            GTK_RESPONSE_REJECT,
                                            NULL);
        gtk_dialog_set_default_response(GTK_DIALOG(dialog), GTK_RESPONSE_CLOSE);
        label_options = _("do you want to close darktable now to manually restore\n"
                          "the database from a backup or delete the corrupted database\n"
                          "and start with a new one?");
      }



      char *label_text = g_markup_printf_escaped(_("an error has occurred while trying to open the database from\n"
                                                   "\n"
                                                   "<span style='italic'>%s</span>\n"
                                                   "\n"
                                                   "it seems that the database is corrupted.\n"
                                                   "%s"
                                                   "%s"),
                                                 dbfilename_data, quick_check_text, label_options);

      g_free(quick_check_text);
      g_free(data_status);

      GtkWidget *content_area = gtk_dialog_get_content_area(GTK_DIALOG (dialog));
      GtkWidget *label = gtk_label_new(NULL);
      gtk_label_set_markup(GTK_LABEL(label), label_text);
      g_free(label_text);
      gtk_container_add(GTK_CONTAINER (content_area), label);

      gtk_widget_show_all(content_area);

      const int resp = gtk_dialog_run(GTK_DIALOG(dialog));

      gtk_widget_destroy(dialog);

      dt_database_destroy(db);
      db = NULL;

      if(resp != GTK_RESPONSE_ACCEPT && resp != GTK_RESPONSE_REJECT)
      {
        fprintf(stderr, "[init] database `%s' is corrupt and can't be opened! either replace it from a backup or "
        "delete the file so that darktable can create a new one the next time. aborting\n", dbfilename_data);
        g_free(data_snap);
        goto error;
      }

      //here were sure that response is either accept (restore from snap) or reject (just delete the damaged db)

      fprintf(stderr, "[init] deleting `%s' on user request", dbfilename_data);

      if(g_unlink(dbfilename_data) == 0)
        fprintf(stderr, " ... ok\n");
      else
        fprintf(stderr, " ... failed\n");

      if(resp == GTK_RESPONSE_ACCEPT && data_snap)
      {
        fprintf(stderr, "[init] restoring `%s' from `%s'...", dbfilename_data, data_snap);
        GError *gerror = NULL;
        if(!g_file_test(dbfilename_data, G_FILE_TEST_EXISTS))
        {
          GFile *src = g_file_new_for_path(data_snap);
          GFile *dest = g_file_new_for_path(dbfilename_data);
          gboolean copy_status = TRUE;
          if(g_file_test(data_snap, G_FILE_TEST_EXISTS))
          {
            copy_status = g_file_copy(src, dest, G_FILE_COPY_NONE, NULL, NULL, NULL, &gerror);
            if(copy_status) copy_status = g_chmod(dbfilename_data, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) == 0;
          }
          else
          {
            // there is nothing to restore, create an empty file
            const int fd = g_open(dbfilename_data, O_CREAT, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
            if(fd < 0 || !g_close(fd, &gerror)) copy_status = FALSE;
          }
          if(copy_status)
            fprintf(stderr, " success!\n");
          else
            fprintf(stderr, " failed!\n");

          g_object_unref(src);
          g_object_unref(dest);
        }
      }
      g_free(data_snap);
      g_free(dbname);
      goto start;
    }
  }

  gchar* libdb_status = _get_pragma_string_val(db->handle, "main.quick_check");
  // next we are looking at the library database
  // does the db contain the new 'db_info' table?
  rc = sqlite3_prepare_v2(db->handle, "select value from main.db_info where key = 'version'", -1, &stmt, NULL);
  if(!g_strcmp0(libdb_status, "ok") && rc == SQLITE_OK && sqlite3_step(stmt) == SQLITE_ROW)
  {
    g_free(libdb_status);//it's ok :)

    // compare the version of the db with what is current for this executable
    const int db_version = sqlite3_column_int(stmt, 0);

    sqlite3_finalize(stmt);
    if(db_version < CURRENT_DATABASE_VERSION_LIBRARY)
    {
      ask_for_upgrade(dbfilename_library, has_gui);

      // older: upgrade
      if(!_upgrade_library_schema(db, db_version))
      {
        // we couldn't upgrade the db for some reason. bail out.
        fprintf(stderr, "[init] database `%s' couldn't be upgraded from version %d to %d. aborting\n", dbname,
                db_version, CURRENT_DATABASE_VERSION_LIBRARY);
        dt_database_destroy(db);
        db = NULL;
        goto error;
      }

      // upgrade was successfull, time for some housekeeping
      sqlite3_exec(db->handle, "VACUUM main", NULL, NULL, NULL);
      sqlite3_exec(db->handle, "ANALYZE main", NULL, NULL, NULL);
    }
    else if(db_version > CURRENT_DATABASE_VERSION_LIBRARY)
    {
      // newer: bail out. it's better than what we did before: delete everything
      fprintf(stderr, "[init] database version of `%s' is too new for this build of darktable. aborting\n",
              dbname);
      dt_database_destroy(db);
      db = NULL;
      goto error;
    }
    // else: the current version, do nothing
  }
  else if(g_strcmp0(libdb_status, "ok") || rc == SQLITE_CORRUPT || rc == SQLITE_NOTADB)
  {
    // oh, bad situation. the database is corrupt and can't be read!
    // we inform the user here and let him decide what to do: exit or delete and try again.

    gchar* quick_check_text = NULL;
    if(g_strcmp0(libdb_status, "ok")) // data_status is not ok
    {
      quick_check_text = g_strdup_printf(_("quick_check said:\n"
                                          "%s \n"), libdb_status);
    }
    else
    {
      quick_check_text = g_strdup(""); // a trick;
    }

    gchar *data_snap = dt_database_get_most_recent_snap(dbfilename_library);

    GtkWidget *dialog;
    GtkDialogFlags dflags = GTK_DIALOG_MODAL | GTK_DIALOG_DESTROY_WITH_PARENT;

    const char* label_options = NULL;

    if(data_snap)
    {
      dialog = gtk_dialog_new_with_buttons(_("darktable - error opening database"),
                                          NULL,
                                          dflags,
                                          _("close darktable"),
                                          GTK_RESPONSE_CLOSE,
                                          _("attempt restore"),
                                          GTK_RESPONSE_ACCEPT,
                                          _("delete database"),
                                          GTK_RESPONSE_REJECT,
                                          NULL);
      gtk_dialog_set_default_response(GTK_DIALOG(dialog), GTK_RESPONSE_ACCEPT);
      label_options = _("do you want to close darktable now to manually restore\n"
                        "the database from a backup, attempt an automatic restore\n"
                        "from the most recent snapshot or delete the corrupted database\n"
                        "and start with a new one?");
    }
    else
    {
      dialog = gtk_dialog_new_with_buttons(_("darktable - error opening database"),
                                          NULL,
                                          dflags,
                                          _("close darktable"),
                                          GTK_RESPONSE_CLOSE,
                                          _("delete database"),
                                          GTK_RESPONSE_REJECT,
                                          NULL);
      gtk_dialog_set_default_response(GTK_DIALOG(dialog), GTK_RESPONSE_CLOSE);
      label_options = _("do you want to close darktable now to manually restore\n"
                        "the database from a backup or delete the corrupted database\n"
                        "and start with a new one?");
    }

    char *label_text = g_markup_printf_escaped(_("an error has occurred while trying to open the database from\n"
                                                 "\n"
                                                 "<span style='italic'>%s</span>\n"
                                                 "\n"
                                                 "it seems that the database is corrupted.\n"
                                                 "%s"
                                                 "%s"),
                                               dbfilename_data, quick_check_text, label_options);

    g_free(quick_check_text);
    g_free(libdb_status);

    GtkWidget *content_area = gtk_dialog_get_content_area(GTK_DIALOG (dialog));
    GtkWidget *label = gtk_label_new(NULL);
    gtk_label_set_markup(GTK_LABEL(label), label_text);
    g_free(label_text);
    gtk_container_add(GTK_CONTAINER (content_area), label);

    gtk_widget_show_all(content_area);

    const int resp = gtk_dialog_run(GTK_DIALOG(dialog));

    gtk_widget_destroy(dialog);

    dt_database_destroy(db);
    db = NULL;

    if(resp != GTK_RESPONSE_ACCEPT && resp != GTK_RESPONSE_REJECT)
    {
      fprintf(stderr, "[init] database `%s' is corrupt and can't be opened! either replace it from a backup or "
        "delete the file so that darktable can create a new one the next time. aborting\n", dbfilename_library);
      g_free(data_snap);
      goto error;
    }

    //here were sure that response is either accept (restore from snap) or reject (just delete the damaged db)

    fprintf(stderr, "[init] deleting `%s' on user request", dbfilename_library);

    if(g_unlink(dbfilename_library) == 0)
      fprintf(stderr, " ... ok\n");
    else
      fprintf(stderr, " ... failed\n");

    if(resp == GTK_RESPONSE_ACCEPT && data_snap)
    {
      fprintf(stderr, "[init] restoring `%s' from `%s'...", dbfilename_library, data_snap);
      GError *gerror = NULL;
      if(!g_file_test(dbfilename_library, G_FILE_TEST_EXISTS))
      {
        GFile *src = g_file_new_for_path(data_snap);
        GFile *dest = g_file_new_for_path(dbfilename_library);
        gboolean copy_status = TRUE;
        if(g_file_test(data_snap, G_FILE_TEST_EXISTS))
        {
          copy_status = g_file_copy(src, dest, G_FILE_COPY_NONE, NULL, NULL, NULL, &gerror);
          if(copy_status) copy_status = g_chmod(dbfilename_library, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) == 0;
        }
        else
        {
          // there is nothing to restore, create an empty file to prevent further backup attempts
          const int fd = g_open(dbfilename_library, O_CREAT, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
          if(fd < 0 || !g_close(fd, &gerror)) copy_status = FALSE;
        }
        if(copy_status)
          fprintf(stderr, " success!\n");
        else
          fprintf(stderr, " failed!\n");
        g_object_unref(src);
        g_object_unref(dest);
      }
    }
    g_free(data_snap);
    g_free(dbname);
    goto start;
  }
  else
  {
    // does it contain the legacy 'settings' table?
    sqlite3_finalize(stmt);
    rc = sqlite3_prepare_v2(db->handle, "select settings from main.settings", -1, &stmt, NULL);
    if(rc == SQLITE_OK && sqlite3_step(stmt) == SQLITE_ROW)
    {
      // the old blob had the version as an int in the first place
      const void *set = sqlite3_column_blob(stmt, 0);
      const int db_version = *(int *)set;
      sqlite3_finalize(stmt);
      if(!_migrate_schema(db, db_version)) // bring the legacy layout to the first one known to our upgrade
                                           // path ...
      {
        // we couldn't migrate the db for some reason. bail out.
        fprintf(stderr, "[init] database `%s' couldn't be migrated from the legacy version %d. aborting\n",
                dbname, db_version);
        dt_database_destroy(db);
        db = NULL;
        goto error;
      }
      if(!_upgrade_library_schema(db, 1)) // ... and upgrade it
      {
        // we couldn't upgrade the db for some reason. bail out.
        fprintf(stderr, "[init] database `%s' couldn't be upgraded from version 1 to %d. aborting\n", dbname,
                CURRENT_DATABASE_VERSION_LIBRARY);
        dt_database_destroy(db);
        db = NULL;
        goto error;
      }
    }
    else
    {
      sqlite3_finalize(stmt);
      _create_library_schema(db); // a brand new db it seems
    }
  }

  // create the in-memory tables
  _create_memory_schema(db);

  // create a table legacy_presets with all the presets from pre-auto-apply-cleanup darktable.
  dt_legacy_presets_create(db);

  // drop table settings -- we don't want old versions of dt to drop our tables
  sqlite3_exec(db->handle, "drop table main.settings", NULL, NULL, NULL);

  // take care of potential bad data in the db.
  _sanitize_db(db);

#ifdef HAVE_ICU
  // check if sqlite is already icu enabled
  // if not enabled expected error: no such function:icu_load_collation
  rc = sqlite3_prepare_v2(db->handle,
                          "SELECT icu_load_collation('en_US', 'english')",
                          -1, &stmt, NULL);
  sqlite3_finalize(stmt);

  if(rc != SQLITE_OK)
  {
    rc = sqlite3IcuInit(db->handle);
    if(rc != SQLITE_OK)
      fprintf(stderr, "[sqlite] init icu extension error %d\n", rc);
  }
#endif

error:
  g_free(dbname);

  return db;
}

void dt_database_destroy(const dt_database_t *db)
{
  sqlite3_close(db->handle);
  if (db->lockfile_data)
  {
    g_unlink(db->lockfile_data);
    g_free(db->lockfile_data);
  }
  if (db->lockfile_library)
  {
    g_unlink(db->lockfile_library);
    g_free(db->lockfile_library);
  }
  g_free(db->dbfilename_data);
  g_free(db->dbfilename_library);
  g_free((dt_database_t *)db);

  sqlite3_shutdown();
}

sqlite3 *dt_database_get(const dt_database_t *db)
{
  return db ? db->handle : NULL;
}

const gchar *dt_database_get_path(const struct dt_database_t *db)
{
  return db->dbfilename_library;
}

static void _database_migrate_to_xdg_structure()
{
  gchar dbfilename[PATH_MAX] = { 0 };
  gchar *conf_db = dt_conf_get_string("database");

  gchar datadir[PATH_MAX] = { 0 };
  dt_loc_get_datadir(datadir, sizeof(datadir));

  if(conf_db && conf_db[0] != '/')
  {
    const char *homedir = getenv("HOME");
    snprintf(dbfilename, sizeof(dbfilename), "%s/%s", homedir, conf_db);
    if(g_file_test(dbfilename, G_FILE_TEST_EXISTS))
    {
      char destdbname[PATH_MAX] = { 0 };
      snprintf(destdbname, sizeof(dbfilename), "%s/%s", datadir, "library.db");
      if(!g_file_test(destdbname, G_FILE_TEST_EXISTS))
      {
        fprintf(stderr, "[init] moving database into new XDG directory structure\n");
        rename(dbfilename, destdbname);
        dt_conf_set_string("database", "library.db");
      }
    }
  }

  g_free(conf_db);
}

/* delete old mipmaps files */
static void _database_delete_mipmaps_files()
{
  /* This migration is intended to be run only from 0.9.x to new cache in 1.0 */

  // Directory
  char cachedir[PATH_MAX] = { 0 }, mipmapfilename[PATH_MAX] = { 0 };
  dt_loc_get_user_cache_dir(cachedir, sizeof(cachedir));

  snprintf(mipmapfilename, sizeof(mipmapfilename), "%s/mipmaps", cachedir);

  if(g_access(mipmapfilename, F_OK) != -1)
  {
    fprintf(stderr, "[mipmap_cache] dropping old version file: %s\n", mipmapfilename);
    g_unlink(mipmapfilename);

    snprintf(mipmapfilename, sizeof(mipmapfilename), "%s/mipmaps.fallback", cachedir);

    if(g_access(mipmapfilename, F_OK) != -1) g_unlink(mipmapfilename);
  }
}

gboolean dt_database_get_lock_acquired(const dt_database_t *db)
{
  return db->lock_acquired;
}

void dt_database_cleanup_busy_statements(const struct dt_database_t *db)
{
  sqlite3_stmt *stmt = NULL;
  while( (stmt = sqlite3_next_stmt(db->handle, NULL)) != NULL)
  {
    const char* sql = sqlite3_sql(stmt);
    if(sqlite3_stmt_busy(stmt))
    {
      dt_print(DT_DEBUG_SQL, "[db busy stmt] non-finalized nor stepped through statement: '%s'\n",sql);
      sqlite3_reset(stmt);
    }
    else {
      dt_print(DT_DEBUG_SQL, "[db busy stmt] non-finalized statement: '%s'\n",sql);
    }
    sqlite3_finalize(stmt);
  }
}

#define ERRCHECK {if (err!=NULL) {dt_print(DT_DEBUG_SQL, "[db maintenance] maintenance error: '%s'\n",err); sqlite3_free(err); err=NULL;}}
void dt_database_perform_maintenance(const struct dt_database_t *db)
{
  char* err = NULL;

  const int main_pre_free_count = _get_pragma_int_val(db->handle, "main.freelist_count");
  const int main_page_size = _get_pragma_int_val(db->handle, "main.page_size");
  const int data_pre_free_count = _get_pragma_int_val(db->handle, "data.freelist_count");
  const int data_page_size = _get_pragma_int_val(db->handle, "data.page_size");

  const guint64 calc_pre_size = (main_pre_free_count*main_page_size) + (data_pre_free_count*data_page_size);

  if(calc_pre_size == 0)
  {
    dt_print(DT_DEBUG_SQL, "[db maintenance] maintenance deemed unnecesary, performing only analyze.\n");
    DT_DEBUG_SQLITE3_EXEC(db->handle, "ANALYZE data", NULL, NULL, &err);
    ERRCHECK
    DT_DEBUG_SQLITE3_EXEC(db->handle, "ANALYZE main", NULL, NULL, &err);
    ERRCHECK
    DT_DEBUG_SQLITE3_EXEC(db->handle, "ANALYZE", NULL, NULL, &err);
    ERRCHECK
    return;
  }

  DT_DEBUG_SQLITE3_EXEC(db->handle, "VACUUM data", NULL, NULL, &err);
  ERRCHECK
  DT_DEBUG_SQLITE3_EXEC(db->handle, "VACUUM main", NULL, NULL, &err);
  ERRCHECK
  DT_DEBUG_SQLITE3_EXEC(db->handle, "ANALYZE data", NULL, NULL, &err);
  ERRCHECK
  DT_DEBUG_SQLITE3_EXEC(db->handle, "ANALYZE main", NULL, NULL, &err);
  ERRCHECK

  // for some reason this is needed in some cases
  // in case above performed vacuum+analyze properly, this is noop.
  DT_DEBUG_SQLITE3_EXEC(db->handle, "VACUUM", NULL, NULL, &err);
  ERRCHECK
  DT_DEBUG_SQLITE3_EXEC(db->handle, "ANALYZE", NULL, NULL, &err);
  ERRCHECK

  const int main_post_free_count = _get_pragma_int_val(db->handle, "main.freelist_count");
  const int data_post_free_count = _get_pragma_int_val(db->handle, "data.freelist_count");

  const guint64 calc_post_size = (main_post_free_count*main_page_size) + (data_post_free_count*data_page_size);
  const gint64 bytes_freed = calc_pre_size - calc_post_size;

  dt_print(DT_DEBUG_SQL, "[db maintenance] maintenance done, %" G_GINT64_FORMAT " bytes freed.\n", bytes_freed);

  if(calc_post_size >= calc_pre_size)
  {
    dt_print(DT_DEBUG_SQL, "[db maintenance] maintenance problem. if no errors logged, it should work fine next time.\n");
  }
}
#undef ERRCHECK

gboolean _ask_for_maintenance(const gboolean has_gui, const gboolean closing_time, const guint64 size)
{
  if(!has_gui)
  {
    return FALSE;
  }

  char *later_info = NULL;
  char *size_info = g_format_size(size);
  const char *config = dt_conf_get_string_const("database/maintenance_check");
  if((closing_time && (!g_strcmp0(config, "on both"))) || !g_strcmp0(config, "on startup"))
  {
    later_info = _("click later to be asked on next startup");
  }
  else if (!closing_time && (!g_strcmp0(config, "on both")))
  {
    later_info = _("click later to be asked when closing darktable");
  }
  else if (!g_strcmp0(config, "on close"))
  {
    later_info = _("click later to be asked next time when closing darktable");
  }

  char *label_text = g_markup_printf_escaped(_("the database could use some maintenance\n"
                                                 "\n"
                                                 "there's <span style='italic'>%s</span> to be freed"
                                                 "\n\n"
                                                 "do you want to proceed now?\n\n"
                                                 "%s\n"
                                                 "you can always change maintenance preferences in core options"),
                                                 size_info, later_info);

    const gboolean shall_perform_maintenance =
      dt_gui_show_standalone_yes_no_dialog(_("darktable - schema maintenance"), label_text,
                                           _("later"), _("yes"));

    g_free(label_text);
    g_free(size_info);

    return shall_perform_maintenance;
}

static inline gboolean _is_mem_db(const struct dt_database_t *db)
{
  return !g_strcmp0(db->dbfilename_data, ":memory:") || !g_strcmp0(db->dbfilename_library, ":memory:");
}

gboolean dt_database_maybe_maintenance(const struct dt_database_t *db, const gboolean has_gui, const gboolean closing_time)
{
  if(_is_mem_db(db))
    return FALSE;

  const char *config = dt_conf_get_string_const("database/maintenance_check");

  if(!g_strcmp0(config, "never"))
  {
    // early bail out on "never"
    dt_print(DT_DEBUG_SQL, "[db maintenance] please consider enabling database maintenance.\n");
    return FALSE;
  }

  gboolean check_for_maintenance = FALSE;
  const gboolean force_maintenance = g_str_has_suffix (config, "(don't ask)");

  if(config)
  {
    if((strstr(config, "on both")) // should cover "(don't ask) suffix
        || (closing_time && (strstr(config, "on close")))
        || (!closing_time && (strstr(config, "on startup"))))
    {
      // we have "on both/on close/on startup" setting, so - checking!
      dt_print(DT_DEBUG_SQL, "[db maintenance] checking for maintenance, due to rule: '%s'.\n", config);
      check_for_maintenance = TRUE;
    }
    // if the config was "never", check_for_vacuum is false.
  }

  if(!check_for_maintenance)
  {
    return FALSE;
  }

  // checking free pages
  const int main_free_count = _get_pragma_int_val(db->handle, "main.freelist_count");
  const int main_page_count = _get_pragma_int_val(db->handle, "main.page_count");
  const int main_page_size = _get_pragma_int_val(db->handle, "main.page_size");

  const int data_free_count = _get_pragma_int_val(db->handle, "data.freelist_count");
  const int data_page_count = _get_pragma_int_val(db->handle, "data.page_count");
  const int data_page_size = _get_pragma_int_val(db->handle, "data.page_size");

  dt_print(DT_DEBUG_SQL,
      "[db maintenance] main: [%d/%d pages], data: [%d/%d pages].\n",
      main_free_count, main_page_count, data_free_count, data_page_count);

  if(main_page_count <= 0 || data_page_count <= 0)
  {
    //something's wrong with PRAGMA page_size returns. early bail.
    dt_print(DT_DEBUG_SQL,
        "[db maintenance] page_count <= 0 : main.page_count: %d, data.page_count: %d \n",
        main_page_count, data_page_count);
    return FALSE;
  }

  // we don't need fine-grained percentages, so let's do ints
  const int main_free_percentage = (main_free_count * 100 ) / main_page_count;
  const int data_free_percentage = (data_free_count * 100 ) / data_page_count;

  const int freepage_ratio = dt_conf_get_int("database/maintenance_freepage_ratio");

  if((main_free_percentage >= freepage_ratio)
      || (data_free_percentage >= freepage_ratio))
  {
    const guint64 calc_size = (main_free_count*main_page_size) + (data_free_count*data_page_size);
    dt_print(DT_DEBUG_SQL, "[db maintenance] maintenance suggested, %" G_GUINT64_FORMAT " bytes to free.\n", calc_size);

    if(force_maintenance || _ask_for_maintenance(has_gui, closing_time, calc_size))
    {
      return TRUE;
    }
  }
  return FALSE;
}

void dt_database_optimize(const struct dt_database_t *db)
{
  if(_is_mem_db(db))
    return;
  // optimize should in most cases be no-op and have no noticeable downsides
  // this should be ran on every exit
  // see: https://www.sqlite.org/pragma.html#pragma_optimize
  DT_DEBUG_SQLITE3_EXEC(db->handle, "PRAGMA optimize", NULL, NULL, NULL);
}

static void _print_backup_progress(int remaining, int total)
{
  // TODO if we have closing splashpage - this can be used to advance progressbar :)
  dt_print(DT_DEBUG_SQL, "[db backup] %d out of %d done\n", total - remaining, total);
}

static int _backup_db(
  sqlite3 *src_db,               /* Database handle to back up */
  const char *src_db_name,       /* Database name to back up */
  const char *dest_filename,      /* Name of file to back up to */
  void(*xProgress)(int, int)  /* Progress function to invoke */
)
{
  sqlite3 *dest_db;             /* Database connection opened on zFilename */
  sqlite3_backup *sb_dest;    /* Backup handle used to copy data */

  /* Open the database file identified by zFilename. */
  int rc = sqlite3_open(dest_filename, &dest_db);

  if(rc == SQLITE_OK)
  {
    /* Open the sqlite3_backup object used to accomplish the transfer */
    sb_dest = sqlite3_backup_init(dest_db, "main", src_db, src_db_name);
    if(sb_dest)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] %s to %s\n", src_db_name, dest_filename);
      gchar *pragma = g_strdup_printf("%s.page_count", src_db_name);
      const int spc = _get_pragma_int_val(src_db, pragma);
      g_free(pragma);
      const int pc = MIN(spc, MAX(5,spc/100));
      do
      {
        rc = sqlite3_backup_step(sb_dest, pc);
        if(xProgress)
          xProgress(
            sqlite3_backup_remaining(sb_dest),
            sqlite3_backup_pagecount(sb_dest)
          );
        if( rc==SQLITE_OK || rc==SQLITE_BUSY || rc==SQLITE_LOCKED )
        {
          sqlite3_sleep(25);
        }
      }
      while( rc==SQLITE_OK || rc==SQLITE_BUSY || rc==SQLITE_LOCKED );

      /* Release resources allocated by backup_init(). */
      (void)sqlite3_backup_finish(sb_dest);
    }
    rc = sqlite3_errcode(dest_db);
  }
  /* Close the database connection opened on database file zFilename
  ** and return the result of this function. */
  (void)sqlite3_close(dest_db);
  return rc;
}

gboolean dt_database_snapshot(const struct dt_database_t *db)
{
  // backing up memory db is pointelss
  if(_is_mem_db(db))
    return FALSE;
  GDateTime *date_now = g_date_time_new_now_local();
  gchar *date_suffix = g_date_time_format(date_now, "%Y%m%d%H%M%S");
  g_date_time_unref(date_now);

  const char *file_pattern = "%s-snp-%s";
  const char *temp_pattern = "%s-tmp-%s";

  gchar *lib_backup_file = g_strdup_printf(file_pattern, db->dbfilename_library, date_suffix);
  gchar *lib_tmpbackup_file = g_strdup_printf(temp_pattern, db->dbfilename_library, date_suffix);

  int rc = _backup_db(db->handle, "main", lib_tmpbackup_file, _print_backup_progress);
  if(!(rc==SQLITE_OK))
  {
    g_unlink(lib_tmpbackup_file);
    g_free(lib_tmpbackup_file);
    g_free(lib_backup_file);
    g_free(date_suffix);
    return FALSE;
  }
  g_rename(lib_tmpbackup_file, lib_backup_file);
  g_chmod(lib_backup_file, S_IRUSR);
  g_free(lib_tmpbackup_file);
  g_free(lib_backup_file);

  gchar *dat_backup_file = g_strdup_printf(file_pattern, db->dbfilename_data, date_suffix);
  gchar *dat_tmpbackup_file = g_strdup_printf(temp_pattern, db->dbfilename_data, date_suffix);

  g_free(date_suffix);

  rc = _backup_db(db->handle, "data", dat_tmpbackup_file, _print_backup_progress);
  if(!(rc==SQLITE_OK))
  {
    g_unlink(dat_tmpbackup_file);
    g_free(dat_tmpbackup_file);
    g_free(dat_backup_file);
    return FALSE;
  }
  g_rename(dat_tmpbackup_file, dat_backup_file);
  g_chmod(dat_backup_file, S_IRUSR);
  g_free(dat_tmpbackup_file);
  g_free(dat_backup_file);

  return TRUE;
}

gboolean dt_database_maybe_snapshot(const struct dt_database_t *db)
{
  if(_is_mem_db(db))
    return FALSE;

  const char *config = dt_conf_get_string_const("database/create_snapshot");
  if(!g_strcmp0(config, "never"))
  {
    // early bail out on "never"
    dt_print(DT_DEBUG_SQL, "[db backup] please consider enabling database snapshots.\n");
    return FALSE;
  }
  if(!g_strcmp0(config, "on close"))
  {
    // early bail out on "on close"
    dt_print(DT_DEBUG_SQL, "[db backup] performing unconditional snapshot.\n");
    return TRUE;
  }

  GTimeSpan span_from_last_snap_required;

  if(!g_strcmp0(config, "once a day"))
  {
    span_from_last_snap_required = G_TIME_SPAN_DAY;
  }
  else if(!g_strcmp0(config, "once a week"))
  {
    span_from_last_snap_required = G_TIME_SPAN_DAY * 7;
  }
  else if(!g_strcmp0(config, "once a month"))
  {
    //average month ;)
    span_from_last_snap_required = G_TIME_SPAN_DAY * 30;
  }
  else
  {
    // early bail out on "invalid value"
    dt_print(DT_DEBUG_SQL, "[db backup] invalid timespan requirement expecting never/on close/once a [day/week/month], got %s.\n", config);
    return TRUE;
  }

  //we're in trouble zone - we have to determine when was the last snapshot done (including version upgrade snapshot) :/
  //this could be easy if we wrote date of last successful backup to config, but that's not really an option since
  //backup may done as last db operation, way after config file is closed. Plus we might be mixing dates of backups for
  //various library.db

  dt_print(DT_DEBUG_SQL, "[db backup] checking snapshots existence.\n");
  GFile *library = g_file_parse_name(db->dbfilename_library);
  GFile *parent = g_file_get_parent(library);

  if(parent == NULL)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] couldn't get library parent!.\n");
    g_object_unref(library);
    return FALSE;
  }

  GError *error = NULL;
  GFileEnumerator *library_dir_files = g_file_enumerate_children(parent, G_FILE_ATTRIBUTE_STANDARD_NAME "," G_FILE_ATTRIBUTE_TIME_MODIFIED, G_FILE_QUERY_INFO_NONE, NULL, &error);

  if(library_dir_files == NULL)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] couldn't enumerate library parent: %s.\n", error->message);
    g_object_unref(parent);
    g_object_unref(library);
    g_error_free(error);
    return FALSE;
  }

  gchar *lib_basename = g_file_get_basename(library);
  g_object_unref(library);

  gchar *lib_snap_format = g_strdup_printf("%s-snp-", lib_basename);
  gchar *lib_backup_format = g_strdup_printf("%s-pre-", lib_basename);
  g_free(lib_basename);

  GFileInfo *info = NULL;
  guint64 last_snap = 0;

  while ((info = g_file_enumerator_next_file(library_dir_files, NULL, &error)))
  {
    const char* fname = g_file_info_get_name(info);
    if(g_str_has_prefix(fname, lib_snap_format) || g_str_has_prefix(fname, lib_backup_format))
    {
      dt_print(DT_DEBUG_SQL, "[db backup] found file: %s.\n", fname);
      if(last_snap == 0)
      {
        last_snap = g_file_info_get_attribute_uint64(info, G_FILE_ATTRIBUTE_TIME_MODIFIED);
        g_object_unref(info);
        continue;
      }
      const guint64 try_snap = g_file_info_get_attribute_uint64(info, G_FILE_ATTRIBUTE_TIME_MODIFIED);
      if(try_snap > last_snap)
      {
        last_snap = try_snap;
      }
    }
    g_object_unref(info);
  }
  g_object_unref(parent);
  g_free(lib_snap_format);
  g_free(lib_backup_format);

  if(error)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] problem enumerating library parent: %s.\n", error->message);
    g_file_enumerator_close(library_dir_files, NULL, NULL);
    g_object_unref(library_dir_files);
    g_error_free(error);
    return FALSE;
  }

  g_file_enumerator_close(library_dir_files, NULL, NULL);
  g_object_unref(library_dir_files);

  GDateTime *date_now = g_date_time_new_now_local();

  // Even if last_snap is 0 (didn't found any snaps) it produces proper date - unix epoch
  GDateTime *date_last_snap = g_date_time_new_from_unix_local(last_snap);

  gchar *now_txt = g_date_time_format(date_now, "%Y%m%d%H%M%S");
  gchar *ls_txt = g_date_time_format(date_last_snap, "%Y%m%d%H%M%S");
  dt_print(DT_DEBUG_SQL, "[db backup] last snap: %s; curr date: %s.\n", ls_txt, now_txt);
  g_free(now_txt);
  g_free(ls_txt);

  GTimeSpan span_from_last_snap = g_date_time_difference(date_now, date_last_snap);

  g_date_time_unref(date_now);
  g_date_time_unref(date_last_snap);

  return span_from_last_snap > span_from_last_snap_required;
}

/* Parse integers in the form d (week days), dd (hours etc), ddd (ordinal days) or dddd (years) */
static gboolean _get_iso8601_int (const gchar *text, gsize length, gint *value)
{
  gsize i;
  guint v = 0;

  if (length < 1 || length > 4)
    return FALSE;

  for (i = 0; i < length; i++)
  {
    const gchar c = text[i];
    if (c < '0' || c > '9')
      return FALSE;
    v = v * 10 + (c - '0');
  }

  *value = v;
  return TRUE;
}

static gint _db_snap_sort(gconstpointer a, gconstpointer b, gpointer user_data)
{
  const gchar* e1 = (gchar *) a;
  const gchar* e2 = (gchar *) b;

  //we assume that both end with date in
  //"%Y%m%d%H%M%S" format

  gchar *datepos1 = g_strrstr(e1, "-snp-");
  gchar *datepos2 = g_strrstr(e2, "-snp-");
  if(!datepos1 || !datepos2)
    return 0;

  datepos1 +=5; //skip "-snp-"
  datepos2 +=5; //skip "-snp-"

  int year,month,day,hour,minute,second;

  if(!_get_iso8601_int(datepos1,    4, &year)   ||
     !_get_iso8601_int(datepos1+4,  2, &month)  ||
     !_get_iso8601_int(datepos1+6,  2, &day)    ||
     !_get_iso8601_int(datepos1+8,  2, &hour)   ||
     !_get_iso8601_int(datepos1+10, 2, &minute) ||
     !_get_iso8601_int(datepos1+12, 2, &second)
    )
  {
    return 0;
  }

  GDateTime *d1=g_date_time_new_local(year, month, day, hour, minute, second);

  if(!_get_iso8601_int(datepos2,    4, &year)   ||
     !_get_iso8601_int(datepos2+4,  2, &month)  ||
     !_get_iso8601_int(datepos2+6,  2, &day)    ||
     !_get_iso8601_int(datepos2+8,  2, &hour)   ||
     !_get_iso8601_int(datepos2+10, 2, &minute) ||
     !_get_iso8601_int(datepos2+12, 2, &second)
    )
  {
    g_date_time_unref(d1);
    return 0;
  }

  GDateTime *d2=g_date_time_new_local(year, month, day, hour, minute, second);

  const gint ret = g_date_time_compare(d1, d2);

  g_date_time_unref(d1);
  g_date_time_unref(d2);

  return ret;
}

char **dt_database_snaps_to_remove(const struct dt_database_t *db)
{
  if(_is_mem_db(db))
    return NULL;

  const int keep_snaps = dt_conf_get_int("database/keep_snapshots");

  if(keep_snaps < 0)
    return NULL;

  dt_print(DT_DEBUG_SQL, "[db backup] checking snapshots existence.\n");
  GFile *lib_file = g_file_parse_name(db->dbfilename_library);
  GFile *lib_parent = g_file_get_parent(lib_file);

  if(lib_parent == NULL)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] couldn't get library parent!.\n");
    g_object_unref(lib_file);
    return NULL;
  }

  GFile *dat_file = g_file_parse_name(db->dbfilename_data);
  GFile *dat_parent = g_file_get_parent(dat_file);

  if(dat_parent == NULL)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] couldn't get data parent!.\n");
    g_object_unref(dat_file);
    g_object_unref(lib_file);
    g_object_unref(lib_parent);
  }

  gchar *lib_basename = g_file_get_basename(lib_file);
  g_object_unref(lib_file);
  gchar *lib_snap_format = g_strdup_printf("%s-snp-", lib_basename);
  gchar *lib_tmp_format = g_strdup_printf("%s-tmp-", lib_basename);
  g_free(lib_basename);

  gchar *dat_basename = g_file_get_basename(dat_file);
  g_object_unref(dat_file);
  gchar *dat_snap_format = g_strdup_printf("%s-snp-", dat_basename);
  gchar *dat_tmp_format = g_strdup_printf("%s-tmp-", dat_basename);
  g_free(dat_basename);

  GQueue *lib_snaps = g_queue_new();
  GQueue *dat_snaps = g_queue_new();
  GQueue *tmplib_snaps = g_queue_new();
  GQueue *tmpdat_snaps = g_queue_new();

  if(g_file_equal(lib_parent, dat_parent))
  {
    //slight optimization if library and data are in same dir, we only have to scan one
    GError *error = NULL;
    GFileEnumerator *library_dir_files = g_file_enumerate_children(lib_parent, G_FILE_ATTRIBUTE_STANDARD_NAME, G_FILE_QUERY_INFO_NONE, NULL, &error);

    if(library_dir_files == NULL)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] couldn't enumerate library parent: %s.\n", error->message);
      g_object_unref(lib_parent);
      g_object_unref(dat_parent);
      g_free(lib_snap_format);
      g_free(dat_snap_format);
      g_free(lib_tmp_format);
      g_free(dat_tmp_format);
      g_queue_free(lib_snaps);
      g_queue_free(dat_snaps);
      g_queue_free(tmplib_snaps);
      g_queue_free(tmpdat_snaps);
      g_error_free(error);
      return NULL;
    }

    GFileInfo *info = NULL;

    while ((info = g_file_enumerator_next_file(library_dir_files, NULL, &error)))
    {
      const char* fname = g_file_info_get_name(info);
      if(g_str_has_prefix(fname, lib_snap_format))
      {
        dt_print(DT_DEBUG_SQL, "[db backup] found file: %s.\n", fname);
        g_queue_insert_sorted(lib_snaps, g_strdup(fname), _db_snap_sort, NULL);
      }
      else if(g_str_has_prefix(fname, dat_snap_format))
      {
        dt_print(DT_DEBUG_SQL, "[db backup] found file: %s.\n", fname);
        g_queue_insert_sorted(dat_snaps, g_strdup(fname), _db_snap_sort, NULL);
      }
      else if(g_str_has_prefix(fname, lib_tmp_format) || g_str_has_prefix(fname, dat_tmp_format))
      {
        //we insert into single queue, since it's just dependent on parent
        g_queue_push_head(tmplib_snaps, g_strdup(fname));
      }
      g_object_unref(info);
    }
    g_free(lib_snap_format);
    g_free(dat_snap_format);

    if(error)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] problem enumerating library parent: %s.\n", error->message);
      g_object_unref(lib_parent);
      g_object_unref(dat_parent);
      g_free(lib_tmp_format);
      g_free(dat_tmp_format);
      g_queue_free_full(lib_snaps, g_free);
      g_queue_free_full(dat_snaps, g_free);
      g_queue_free_full(tmplib_snaps, g_free);
      g_queue_free_full(tmpdat_snaps, g_free);
      g_file_enumerator_close(library_dir_files, NULL, NULL);
      g_object_unref(library_dir_files);
      g_error_free(error);
      return NULL;
    }
    g_file_enumerator_close(library_dir_files, NULL, NULL);
    g_object_unref(library_dir_files);
  }
  else
  {
    //well... fun.

    GError *error = NULL;
    GFileEnumerator *library_dir_files = g_file_enumerate_children(lib_parent, G_FILE_ATTRIBUTE_STANDARD_NAME, G_FILE_QUERY_INFO_NONE, NULL, &error);
    if(library_dir_files == NULL)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] couldn't enumerate library parent: %s.\n", error->message);
      g_object_unref(lib_parent);
      g_object_unref(dat_parent);
      g_free(lib_snap_format);
      g_free(dat_snap_format);
      g_free(lib_tmp_format);
      g_free(dat_tmp_format);
      g_error_free(error);
      g_queue_free(lib_snaps);
      g_queue_free(dat_snaps);
      g_queue_free(tmplib_snaps);
      g_queue_free(tmpdat_snaps);
      return NULL;
    }

    GFileEnumerator *data_dir_files = g_file_enumerate_children(dat_parent, G_FILE_ATTRIBUTE_STANDARD_NAME, G_FILE_QUERY_INFO_NONE, NULL, &error);
    if(data_dir_files == NULL)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] couldn't enumerate data parent: %s.\n", error->message);
      g_object_unref(lib_parent);
      g_object_unref(dat_parent);
      g_free(lib_snap_format);
      g_free(dat_snap_format);
      g_free(lib_tmp_format);
      g_free(dat_tmp_format);
      g_file_enumerator_close(library_dir_files, NULL, NULL);
      g_object_unref(library_dir_files);
      g_error_free(error);
      g_queue_free(lib_snaps);
      g_queue_free(dat_snaps);
      g_queue_free(tmplib_snaps);
      g_queue_free(tmpdat_snaps);
      return NULL;
    }

    GFileInfo *info = NULL;

    while ((info = g_file_enumerator_next_file(library_dir_files, NULL, &error)))
    {
      const char* fname = g_file_info_get_name(info);
      if(g_str_has_prefix(fname, lib_snap_format))
      {
        dt_print(DT_DEBUG_SQL, "[db backup] found file: %s.\n", fname);
        g_queue_insert_sorted(lib_snaps, g_strdup(fname), _db_snap_sort, NULL);
      }
      else if(g_str_has_prefix(fname, lib_tmp_format) || g_str_has_prefix(fname, dat_tmp_format))
      {
        // we remove all incomplete snaps matching pattern in BOTH dirs
        g_queue_push_head(tmplib_snaps, g_strdup(fname));
      }
      g_object_unref(info);
    }
    g_free(lib_snap_format);

    if(error)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] problem enumerating library parent: %s.\n", error->message);
      g_object_unref(lib_parent);
      g_object_unref(dat_parent);
      g_free(lib_tmp_format);
      g_free(dat_tmp_format);
      g_queue_free_full(lib_snaps, g_free);
      g_queue_free(dat_snaps);
      g_queue_free_full(tmplib_snaps, g_free);
      g_queue_free(tmpdat_snaps);
      g_file_enumerator_close(library_dir_files, NULL, NULL);
      g_object_unref(library_dir_files);
      g_file_enumerator_close(data_dir_files, NULL, NULL);
      g_object_unref(data_dir_files);
      g_error_free(error);
      return NULL;
    }
    g_file_enumerator_close(library_dir_files, NULL, NULL);
    g_object_unref(library_dir_files);

    while ((info = g_file_enumerator_next_file(data_dir_files, NULL, &error)))
    {
      const char* fname = g_file_info_get_name(info);
      if(g_str_has_prefix(fname, dat_snap_format))
      {
        dt_print(DT_DEBUG_SQL, "[db backup] found file: %s.\n", fname);
        g_queue_insert_sorted(dat_snaps, g_strdup(fname), _db_snap_sort, NULL);
      }
      else if(g_str_has_prefix(fname, lib_tmp_format) || g_str_has_prefix(fname, dat_tmp_format))
      {
        //we add to queue both matches - it just depends on parent
        g_queue_push_head(tmpdat_snaps, g_strdup(fname));
      }
      g_object_unref(info);
    }
    g_free(dat_snap_format);
    g_free(lib_tmp_format);
    g_free(dat_tmp_format);

    if(error)
    {
      dt_print(DT_DEBUG_SQL, "[db backup] problem enumerating data parent: %s.\n", error->message);
      g_object_unref(lib_parent);
      g_object_unref(dat_parent);
      g_queue_free_full(lib_snaps, g_free);
      g_queue_free_full(dat_snaps, g_free);
      g_queue_free_full(tmplib_snaps, g_free);
      g_queue_free_full(tmpdat_snaps, g_free);
      g_file_enumerator_close(data_dir_files, NULL, NULL);
      g_object_unref(data_dir_files);
      g_error_free(error);
      return NULL;
    }

    g_file_enumerator_close(data_dir_files, NULL, NULL);
    g_object_unref(data_dir_files);
  }

  // here we have list of snaps sorted in date order, now we have to
  // create from that list of snaps to be deleted and return that :D

  GPtrArray *ret = g_ptr_array_new();

  gchar *lib_parent_path = g_file_get_path(lib_parent);
  g_object_unref(lib_parent);

  while(g_queue_get_length(lib_snaps) > keep_snaps)
  {
    gchar *head = g_queue_pop_head(lib_snaps);
    g_ptr_array_add(ret, g_strconcat(lib_parent_path, G_DIR_SEPARATOR_S, head, NULL));
    g_free(head);
  }
  while(!g_queue_is_empty(tmplib_snaps))
  {
    gchar *head = g_queue_pop_head(tmplib_snaps);
    g_ptr_array_add(ret, g_strconcat(lib_parent_path, G_DIR_SEPARATOR_S, head, NULL));
    g_free(head);
  }
  g_free(lib_parent_path);
  g_queue_free_full(lib_snaps, g_free);
  g_queue_free_full(tmplib_snaps, g_free); // should be totally freed, but eh - this won't make doublefree

  gchar *dat_parent_path = g_file_get_path(dat_parent);
  g_object_unref(dat_parent);

  while(g_queue_get_length(dat_snaps) > keep_snaps)
  {
    gchar *head = g_queue_pop_head(dat_snaps);
    g_ptr_array_add(ret, g_strconcat(dat_parent_path, G_DIR_SEPARATOR_S, head, NULL));
    g_free(head);
  }
  while(!g_queue_is_empty(tmpdat_snaps))
  {
    gchar *head = g_queue_pop_head(tmpdat_snaps);
    g_ptr_array_add(ret, g_strconcat(dat_parent_path, G_DIR_SEPARATOR_S, head, NULL));
    g_free(head);
  }
  g_free(dat_parent_path);
  g_queue_free_full(dat_snaps, g_free);
  g_queue_free_full(tmpdat_snaps, g_free);

  g_ptr_array_add (ret, NULL);

  return (char**)g_ptr_array_free(ret, FALSE);
}

gchar *dt_database_get_most_recent_snap(const char* db_filename)
{
  if(!g_strcmp0(db_filename, ":memory:"))
    return NULL;

  dt_print(DT_DEBUG_SQL, "[db backup] checking snapshots existence.\n");
  GFile *db_file = g_file_parse_name(db_filename);
  GFile *parent = g_file_get_parent(db_file);

  if(parent == NULL)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] couldn't get database parent!.\n");
    g_object_unref(db_file);
    return NULL;
  }

  GError *error = NULL;
  GFileEnumerator *db_dir_files = g_file_enumerate_children(parent, G_FILE_ATTRIBUTE_STANDARD_NAME "," G_FILE_ATTRIBUTE_TIME_MODIFIED, G_FILE_QUERY_INFO_NONE, NULL, &error);

  if(db_dir_files == NULL)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] couldn't enumerate database parent: %s.\n", error->message);
    g_object_unref(parent);
    g_object_unref(db_file);
    g_error_free(error);
    return NULL;
  }

  gchar *db_basename = g_file_get_basename(db_file);
  g_object_unref(db_file);

  gchar *db_snap_format = g_strdup_printf("%s-snp-", db_basename);
  gchar *db_backup_format = g_strdup_printf("%s-pre-", db_basename);
  g_free(db_basename);

  GFileInfo *info = NULL;
  guint64 last_snap = 0;
  gchar *last_snap_name = NULL;

  while ((info = g_file_enumerator_next_file(db_dir_files, NULL, &error)))
  {
    const char* fname = g_file_info_get_name(info);
    if(g_str_has_prefix(fname, db_snap_format) || g_str_has_prefix(fname, db_backup_format))
    {
      dt_print(DT_DEBUG_SQL, "[db backup] found file: %s.\n", fname);
      if(last_snap == 0)
      {
        last_snap = g_file_info_get_attribute_uint64(info, G_FILE_ATTRIBUTE_TIME_MODIFIED);
        last_snap_name = g_strdup(fname);
        g_object_unref(info);
        continue;
      }
      guint64 try_snap = g_file_info_get_attribute_uint64(info, G_FILE_ATTRIBUTE_TIME_MODIFIED);
      if(try_snap > last_snap)
      {
        last_snap = try_snap;
        g_free(last_snap_name);
        last_snap_name = g_strdup(fname);
      }
    }
    g_object_unref(info);
  }
  g_free(db_snap_format);
  g_free(db_backup_format);

  if(error)
  {
    dt_print(DT_DEBUG_SQL, "[db backup] problem enumerating database parent: %s.\n", error->message);
    g_file_enumerator_close(db_dir_files, NULL, NULL);
    g_object_unref(db_dir_files);
    g_error_free(error);
    g_free(last_snap_name);
    return NULL;
  }

  g_file_enumerator_close(db_dir_files, NULL, NULL);
  g_object_unref(db_dir_files);

  if(!last_snap_name)
  {
    g_object_unref(parent);
    return NULL;
  }

  gchar *parent_path = g_file_get_path(parent);
  g_object_unref(parent);

  gchar *ret = g_strconcat(parent_path, G_DIR_SEPARATOR_S, last_snap_name, NULL);
  g_free(parent_path);
  g_free(last_snap_name);

  return ret;
}

// Nested transactions support
//
// NOTE: the nested support is actually not activated (see || TRUE below). This current
//       implementation is just a refactoring of the previous code using:
//          - dt_database_start_transaction()
//          - dt_database_release_transaction()
//          - dt_database_rollback_transaction()
//
//       With this refactoring we can count and check for nested transaction and unmatched
//       transaction routines. And it has been done to help further implementation for
//       proper threading and nested transaction support.
//
void dt_database_start_transaction(const struct dt_database_t *db)
{
  const int trxid = dt_atomic_add_int(&_trxid, 1);

  // if top level a simple unamed transaction is used BEGIN / COMMIT / ROLLBACK
  // otherwise we use a savepoint (named transaction).

  if(trxid == 0 || TRUE)
  {
    // In theads application it may be safer to use an IMMEDIATE transaction:
    // "BEGIN IMMEDIATE TRANSACTION"
    DT_DEBUG_SQLITE3_EXEC(dt_database_get(db), "BEGIN TRANSACTION", NULL, NULL, NULL);
  }
#ifdef USE_NESTED_TRANSACTIONS
  else
  {
    char SQLTRX[32] = { 0 };
    g_snprintf(SQLTRX, sizeof(SQLTRX), "SAVEPOINT trx%d", trxid);
    DT_DEBUG_SQLITE3_EXEC(dt_database_get(db), SQLTRX, NULL, NULL, NULL);
  }
#endif

  if(trxid > MAX_NESTED_TRANSACTIONS)
    fprintf(stderr, "[dt_database_start_transaction] more than %d nested transaction\n", MAX_NESTED_TRANSACTIONS);
}

void dt_database_release_transaction(const struct dt_database_t *db)
{
  const int trxid = dt_atomic_sub_int(&_trxid, 1);

  if(trxid <= 0)
    fprintf(stderr, "[dt_database_release_transaction] COMMIT outside a transaction\n");

  if(trxid == 1 || TRUE)
  {
    DT_DEBUG_SQLITE3_EXEC(dt_database_get(db), "COMMIT TRANSACTION", NULL, NULL, NULL);
  }
#ifdef USE_NESTED_TRANSACTIONS
  else
  {
    char SQLTRX[64] = { 0 };
    g_snprintf(SQLTRX, sizeof(SQLTRX), "RELEASE SAVEPOINT trx%d", trxid - 1);
    DT_DEBUG_SQLITE3_EXEC(dt_database_get(db), SQLTRX, NULL, NULL, NULL);
  }
#endif
}

void dt_database_rollback_transaction(const struct dt_database_t *db)
{
  const int trxid = dt_atomic_sub_int(&_trxid, 1);

  if(trxid <= 0)
    fprintf(stderr, "[dt_database_rollback_transaction] ROLLBACK outside a transaction\n");

  if(trxid == 1 || TRUE)
  {
    DT_DEBUG_SQLITE3_EXEC(dt_database_get(db), "ROLLBACK TRANSACTION", NULL, NULL, NULL);
  }
#ifdef USE_NESTED_TRANSACTIONS
  else
  {
    char SQLTRX[64] = { 0 };
    g_snprintf(SQLTRX, sizeof(SQLTRX), "ROLLBACK TRANSACTION TO SAVEPOINT trx%d", trxid - 1);
    DT_DEBUG_SQLITE3_EXEC(dt_database_get(db), SQLTRX, NULL, NULL, NULL);
  }
#endif
}

// clang-format off
// modelines: These editor modelines have been set for all relevant files by tools/update_modelines.py
// vim: shiftwidth=2 expandtab tabstop=2 cindent
// kate: tab-indents: off; indent-width 2; replace-tabs on; indent-mode cstyle; remove-trailing-spaces modified;
// clang-format on

