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*****************************************************************************/

/** @file pars/pars0sym.cc
 SQL parser symbol table

 Created 12/15/1997 Heikki Tuuri
 *******************************************************/
#include "current_thd.h"

#include "pars0sym.h"

#include "data0data.h"
#include "data0type.h"
#include "dict0dd.h"
#include "eval0eval.h"
#include "mem0mem.h"
#include "pars0grm.h"
#include "pars0pars.h"
#include "que0que.h"
#include "row0sel.h"

/** Creates a symbol table for a single stored procedure or query.
 @return own: symbol table */
sym_tab_t *sym_tab_create(
    mem_heap_t *heap) /*!< in: memory heap where to create */
{
  sym_tab_t *sym_tab;

  sym_tab = static_cast<sym_tab_t *>(mem_heap_alloc(heap, sizeof(sym_tab_t)));

  UT_LIST_INIT(sym_tab->sym_list);
  UT_LIST_INIT(sym_tab->func_node_list);

  sym_tab->heap = heap;

  return (sym_tab);
}

/** Frees the memory allocated dynamically AFTER parsing phase for variables
 etc. in the symbol table. Does not free the mem heap where the table was
 originally created. Frees also SQL explicit cursor definitions. */
void sym_tab_free_private(sym_tab_t *sym_tab) /*!< in, own: symbol table */
{
  THD *thd = current_thd;

  for (auto sym : sym_tab->sym_list) {
    /* Close the tables opened in pars_retrieve_table_def(). */

    if (sym->token_type == SYM_TABLE_REF_COUNTED) {
      if (sym->mdl != nullptr) {
        dd_table_close(sym->table, thd, &sym->mdl, false);
      } else {
        dd_table_close(sym->table, nullptr, nullptr, false);
      }

      sym->table = nullptr;
      sym->resolved = false;
      sym->token_type = SYM_UNSET;
      sym->mdl = nullptr;
    }

    eval_node_free_val_buf(sym);

    if (sym->prefetch_buf) {
      sel_col_prefetch_buf_free(sym->prefetch_buf);
    }

    if (sym->cursor_def) {
      que_graph_free_recursive(sym->cursor_def);
    }
  }

  for (auto func : sym_tab->func_node_list) {
    eval_node_free_val_buf(func);
  }
}

/** Adds an integer literal to a symbol table.
 @return symbol table node */
sym_node_t *sym_tab_add_int_lit(sym_tab_t *sym_tab, /*!< in: symbol table */
                                ulint val)          /*!< in: integer value */
{
  sym_node_t *node;
  byte *data;

  node = static_cast<sym_node_t *>(
      mem_heap_alloc(sym_tab->heap, sizeof(sym_node_t)));

  node->common.type = QUE_NODE_SYMBOL;

  node->table = nullptr;
  node->resolved = true;
  node->token_type = SYM_LIT;

  node->indirection = nullptr;

  dtype_set(dfield_get_type(&node->common.val), DATA_INT, 0, 4);

  data = static_cast<byte *>(mem_heap_alloc(sym_tab->heap, 4));
  mach_write_to_4(data, val);

  dfield_set_data(&(node->common.val), data, 4);

  node->common.val_buf_size = 0;
  node->prefetch_buf = nullptr;
  node->cursor_def = nullptr;

  UT_LIST_ADD_LAST(sym_tab->sym_list, node);

  node->like_node = nullptr;

  node->sym_table = sym_tab;

  return (node);
}

/** Adds a string literal to a symbol table.
 @return symbol table node */
sym_node_t *sym_tab_add_str_lit(sym_tab_t *sym_tab, /*!< in: symbol table */
                                const byte *str, /*!< in: string with no quotes
                                                 around it */
                                ulint len)       /*!< in: string length */
{
  sym_node_t *node;
  byte *data;

  node = static_cast<sym_node_t *>(
      mem_heap_alloc(sym_tab->heap, sizeof(sym_node_t)));

  node->common.type = QUE_NODE_SYMBOL;

  node->table = nullptr;
  node->resolved = true;
  node->token_type = SYM_LIT;

  node->indirection = nullptr;

  dtype_set(dfield_get_type(&node->common.val), DATA_VARCHAR, DATA_ENGLISH, 0);

  data = (len) ? static_cast<byte *>(mem_heap_dup(sym_tab->heap, str, len))
               : nullptr;

  dfield_set_data(&(node->common.val), data, len);

  node->common.val_buf_size = 0;
  node->prefetch_buf = nullptr;
  node->cursor_def = nullptr;

  UT_LIST_ADD_LAST(sym_tab->sym_list, node);

  node->like_node = nullptr;

  node->sym_table = sym_tab;

  return (node);
}

/** Add a bound literal to a symbol table.
 @return symbol table node */
sym_node_t *sym_tab_add_bound_lit(
    sym_tab_t *sym_tab, /*!< in: symbol table */
    const char *name,   /*!< in: name of bound literal */
    ulint *lit_type)    /*!< out: type of literal (PARS_*_LIT) */
{
  sym_node_t *node;
  pars_bound_lit_t *blit;
  ulint len = 0;

  blit = pars_info_get_bound_lit(sym_tab->info, name);
  ut_a(blit);

  node = static_cast<sym_node_t *>(
      mem_heap_alloc(sym_tab->heap, sizeof(sym_node_t)));

  node->common.type = QUE_NODE_SYMBOL;
  node->common.brother = node->common.parent = nullptr;

  node->table = nullptr;
  node->resolved = true;
  node->token_type = SYM_LIT;

  node->indirection = nullptr;

  switch (blit->type) {
    case DATA_FIXBINARY:
      len = blit->length;
      *lit_type = PARS_FIXBINARY_LIT;
      break;

    case DATA_BLOB:
      *lit_type = PARS_BLOB_LIT;
      break;

    case DATA_VARCHAR:
      *lit_type = PARS_STR_LIT;
      break;

    case DATA_CHAR:
      ut_a(blit->length > 0);

      len = blit->length;
      *lit_type = PARS_STR_LIT;
      break;

    case DATA_INT:
      ut_a(blit->length > 0);
      ut_a(blit->length <= 8);

      len = blit->length;
      *lit_type = PARS_INT_LIT;
      break;

    default:
      ut_error;
  }

  dtype_set(dfield_get_type(&node->common.val), blit->type, blit->prtype, len);

  dfield_set_data(&(node->common.val), blit->address, blit->length);

  node->common.val_buf_size = 0;
  node->prefetch_buf = nullptr;
  node->cursor_def = nullptr;

  UT_LIST_ADD_LAST(sym_tab->sym_list, node);

  blit->node = node;
  node->like_node = nullptr;
  node->sym_table = sym_tab;

  return (node);
}

/**********************************************************************
Rebind literal to a node in the symbol table. */
sym_node_t *sym_tab_rebind_lit(
    /* out: symbol table node */
    sym_node_t *node,    /* in: node that is bound to literal*/
    const void *address, /* in: pointer to data */
    ulint length)        /* in: length of data */
{
  dfield_t *dfield = que_node_get_val(node);
  dtype_t *dtype = dfield_get_type(dfield);

  ut_a(node->token_type == SYM_LIT);

  dfield_set_data(&node->common.val, address, length);

  if (node->like_node) {
    ut_a(dtype_get_mtype(dtype) == DATA_CHAR ||
         dtype_get_mtype(dtype) == DATA_VARCHAR);

    /* Don't force [false] creation of sub-nodes (for LIKE) */
    pars_like_rebind(node, static_cast<const byte *>(address), length);
  }

  /* FIXME: What's this ? */
  node->common.val_buf_size = 0;

  if (node->prefetch_buf) {
    sel_col_prefetch_buf_free(node->prefetch_buf);
    node->prefetch_buf = nullptr;
  }

  if (node->cursor_def) {
    que_graph_free_recursive(node->cursor_def);
    node->cursor_def = nullptr;
  }

  return (node);
}

/** Adds an SQL null literal to a symbol table.
 @return symbol table node */
sym_node_t *sym_tab_add_null_lit(sym_tab_t *sym_tab) /*!< in: symbol table */
{
  sym_node_t *node;

  node = static_cast<sym_node_t *>(
      mem_heap_alloc(sym_tab->heap, sizeof(sym_node_t)));

  node->common.type = QUE_NODE_SYMBOL;

  node->table = nullptr;
  node->resolved = true;
  node->token_type = SYM_LIT;

  node->indirection = nullptr;

  dfield_get_type(&node->common.val)->mtype = DATA_ERROR;

  dfield_set_null(&node->common.val);

  node->common.val_buf_size = 0;
  node->prefetch_buf = nullptr;
  node->cursor_def = nullptr;

  UT_LIST_ADD_LAST(sym_tab->sym_list, node);

  node->like_node = nullptr;

  node->sym_table = sym_tab;

  return (node);
}

/** Adds an identifier to a symbol table.
 @return symbol table node */
sym_node_t *sym_tab_add_id(sym_tab_t *sym_tab, /*!< in: symbol table */
                           byte *name,         /*!< in: identifier name */
                           ulint len)          /*!< in: identifier length */
{
  sym_node_t *node;

  node =
      static_cast<sym_node_t *>(mem_heap_zalloc(sym_tab->heap, sizeof(*node)));

  node->common.type = QUE_NODE_SYMBOL;

  node->name = mem_heap_strdupl(sym_tab->heap, (char *)name, len);
  node->name_len = len;

  UT_LIST_ADD_LAST(sym_tab->sym_list, node);

  dfield_set_null(&node->common.val);

  node->sym_table = sym_tab;

  return (node);
}

/** Add a bound identifier to a symbol table.
 @return symbol table node */
sym_node_t *sym_tab_add_bound_id(sym_tab_t *sym_tab, /*!< in: symbol table */
                                 const char *name) /*!< in: name of bound id */
{
  sym_node_t *node;
  pars_bound_id_t *bid;

  bid = pars_info_get_bound_id(sym_tab->info, name);
  ut_a(bid);

  node = static_cast<sym_node_t *>(
      mem_heap_alloc(sym_tab->heap, sizeof(sym_node_t)));

  node->common.type = QUE_NODE_SYMBOL;

  node->table = nullptr;
  node->resolved = false;
  node->token_type = SYM_UNSET;
  node->indirection = nullptr;

  node->name = mem_heap_strdup(sym_tab->heap, bid->id);
  node->name_len = strlen(node->name);

  UT_LIST_ADD_LAST(sym_tab->sym_list, node);

  dfield_set_null(&node->common.val);

  node->common.val_buf_size = 0;
  node->prefetch_buf = nullptr;
  node->cursor_def = nullptr;

  node->like_node = nullptr;

  node->sym_table = sym_tab;

  return (node);
}
