# -*- coding: utf-8 -*-
# Copyright 2017-2018 Davide Alberani <da@erlug.linux.it>
#
# This program 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 2 of the License, or
# (at your option) any later version.
#
# This program 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 this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

"""
This package provides the IMDbS3AccessSystem class used to access IMDb's data
through the Amazon S3 dataset.

The :func:`imdb.IMDb` function will return an instance of this class when
called with the ``accessSystem`` parameter is set to "s3" or "s3dataset".
"""

from __future__ import absolute_import, division, print_function, unicode_literals

import logging
import sqlalchemy
from operator import itemgetter
from imdb import IMDbBase
from .utils import DB_TRANSFORM, title_soundex, name_soundexes, scan_titles, scan_names

from imdb.Movie import Movie
from imdb.Person import Person


def split_array(text):
    """Split a string assuming it's an array.

    :param text: the text to split
    :type text: str
    :returns: list of splitted strings
    :rtype: list
    """
    if not isinstance(text, str):
        return text
    # for some reason, titles.akas.tsv.gz contains \x02 as a separator
    sep = ',' if ',' in text else '\x02'
    return text.split(sep)


class IMDbS3AccessSystem(IMDbBase):
    """The class used to access IMDb's data through the s3 dataset."""

    accessSystem = 's3'
    _s3_logger = logging.getLogger('imdbpy.parser.s3')
    _metadata = sqlalchemy.MetaData()

    def __init__(self, uri, adultSearch=True, *arguments, **keywords):
        """Initialize the access system."""
        IMDbBase.__init__(self, *arguments, **keywords)
        self._engine = sqlalchemy.create_engine(uri, encoding='utf-8', echo=False)
        self._metadata.bind = self._engine
        self._metadata.reflect()
        self.T = self._metadata.tables

    def _rename(self, table, data):
        for column, conf in DB_TRANSFORM.get(table, {}).items():
            if 'rename' not in conf:
                continue
            if column not in data:
                continue
            data[conf['rename']] = data[column]
            del data[column]
        return data

    def _clean(self, data, keys_to_remove=None):
        if keys_to_remove is None:
            keys_to_remove = []
        for key in list(data.keys()):
            if key in keys_to_remove or data[key] in (None, '', []):
                del data[key]
        return data

    def _base_title_info(self, movieID, movies_cache=None, persons_cache=None):
        if movies_cache is None:
            movies_cache = {}
        if persons_cache is None:
            persons_cache = {}
        if movieID in movies_cache:
            return movies_cache[movieID]
        tb = self.T['title_basics']
        movie = tb.select(tb.c.tconst == movieID).execute().fetchone() or {}
        data = self._rename('title_basics', dict(movie))
        data['year'] = str(data.get('startYear') or '')
        if 'endYear' in data and data['endYear']:
            data['year'] += '-%s' % data['endYear']
        genres = data.get('genres') or ''
        data['genres'] = split_array(genres.lower())
        if 'runtimes' in data and data['runtimes']:
            data['runtimes'] = [data['runtimes']]
        self._clean(data, ('startYear', 'endYear', 'movieID'))
        movies_cache[movieID] = data
        return data

    def _base_person_info(self, personID, movies_cache=None, persons_cache=None):
        if movies_cache is None:
            movies_cache = {}
        if persons_cache is None:
            persons_cache = {}
        if personID in persons_cache:
            return persons_cache[personID]
        nb = self.T['name_basics']
        person = nb.select(nb.c.nconst == personID).execute().fetchone() or {}
        data = self._rename('name_basics', dict(person))
        movies = []
        for movieID in split_array(data.get('known for') or ''):
            if not movieID:
                continue
            movieID = int(movieID)
            movie_data = self._base_title_info(movieID, movies_cache=movies_cache, persons_cache=persons_cache)
            movie = Movie(movieID=movieID, data=movie_data, accessSystem=self.accessSystem)
            movies.append(movie)
        data['known for'] = movies
        self._clean(data, ('ns_soundex', 'sn_soundex', 's_soundex', 'personID'))
        persons_cache[personID] = data
        return data

    def get_movie_main(self, movieID):
        movieID = int(movieID)
        data = self._base_title_info(movieID)
        _movies_cache = {movieID: data}
        _persons_cache = {}

        tc = self.T['title_crew']
        movie = tc.select(tc.c.tconst == movieID).execute().fetchone() or {}
        tc_data = self._rename('title_crew', dict(movie))
        writers = []
        directors = []
        for key, target in (('director', directors), ('writer', writers)):
            for personID in split_array(tc_data.get(key) or ''):
                if not personID:
                    continue
                personID = int(personID)
                person_data = self._base_person_info(personID,
                                                     movies_cache=_movies_cache,
                                                     persons_cache=_persons_cache)
                person = Person(personID=personID, data=person_data, accessSystem=self.accessSystem)
                target.append(person)
        tc_data['director'] = directors
        tc_data['writer'] = writers
        data.update(tc_data)

        te = self.T['title_episode']
        movie = tc.select(te.c.tconst == movieID).execute().fetchone() or {}
        te_data = self._rename('title_episode', dict(movie))
        if 'parentTconst' in te_data:
            te_data['episodes of'] = self._base_title_info(te_data['parentTconst'])
        self._clean(te_data, ('parentTconst',))
        data.update(te_data)

        tp = self.T['title_principals']
        movie_rows = tp.select(tp.c.tconst == movieID).execute().fetchall() or {}
        roles = {}
        for movie_row in movie_rows:
            movie_row = dict(movie_row)
            tp_data = self._rename('title_principals', dict(movie_row))
            category = tp_data.get('category')
            if not category:
                continue
            if category in ('actor', 'actress', 'self'):
                category = 'cast'
            roles.setdefault(category, []).append(movie_row)
        for role in roles:
            roles[role].sort(key=itemgetter('ordering'))
            persons = []
            for person_info in roles[role]:
                personID = person_info.get('nconst')
                if not personID:
                    continue
                person_data = self._base_person_info(personID,
                                                     movies_cache=_movies_cache,
                                                     persons_cache=_persons_cache)
                person = Person(personID=personID, data=person_data,
                                billingPos=person_info.get('ordering'),
                                currentRole=person_info.get('characters'),
                                notes=person_info.get('job'),
                                accessSystem=self.accessSystem)
                persons.append(person)
            data[role] = persons

        tr = self.T['title_ratings']
        movie = tr.select(tr.c.tconst == movieID).execute().fetchone() or {}
        tr_data = self._rename('title_ratings', dict(movie))
        data.update(tr_data)

        ta = self.T['title_akas']
        akas = ta.select(ta.c.titleId == movieID).execute()
        akas_list = []
        for aka in akas:
            ta_data = self._rename('title_akas', dict(aka)) or {}
            for key in list(ta_data.keys()):
                if not ta_data[key]:
                    del ta_data[key]
            for key in 't_soundex', 'movieID':
                if key in ta_data:
                    del ta_data[key]
            for key in 'types', 'attributes':
                if key not in ta_data:
                    continue
                ta_data[key] = split_array(ta_data[key])
            akas_list.append(ta_data)
        if akas_list:
            data['akas'] = akas_list

        self._clean(data, ('movieID', 't_soundex'))
        return {'data': data, 'info sets': self.get_movie_infoset()}

    # we don't really have plot information, yet
    get_movie_plot = get_movie_main

    def get_person_main(self, personID):
        personID = int(personID)
        data = self._base_person_info(personID)
        self._clean(data, ('personID',))
        return {'data': data, 'info sets': self.get_person_infoset()}

    get_person_filmography = get_person_main
    get_person_biography = get_person_main

    def _search_movie(self, title, results, _episodes=False):
        title = title.strip()
        if not title:
            return []
        results = []
        t_soundex = title_soundex(title)
        tb = self.T['title_basics']
        conditions = [tb.c.t_soundex == t_soundex]
        if _episodes:
            conditions.append(tb.c.titleType == 'episode')
        results = tb.select(sqlalchemy.and_(*conditions)).execute()
        results = [(x['tconst'], self._clean(self._rename('title_basics', dict(x)), ('t_soundex',)))
                   for x in results]

        # Also search the AKAs
        ta = self.T['title_akas']
        ta_conditions = [ta.c.t_soundex == t_soundex]
        ta_results = ta.select(sqlalchemy.and_(*ta_conditions)).execute()
        ta_results = [(x['titleId'], self._clean(self._rename('title_akas', dict(x)), ('t_soundex',)))
                      for x in ta_results]
        results += ta_results

        results = scan_titles(results, title)
        results = [x[1] for x in results]
        return results

    def _search_episode(self, title, results):
        return self._search_movie(title, results=results, _episodes=True)

    def _search_person(self, name, results):
        name = name.strip()
        if not name:
            return []
        results = []
        ns_soundex, sn_soundex, s_soundex = name_soundexes(name)
        nb = self.T['name_basics']
        conditions = [nb.c.ns_soundex == ns_soundex]
        if sn_soundex:
            conditions.append(nb.c.sn_soundex == sn_soundex)
        if s_soundex:
            conditions.append(nb.c.s_soundex == s_soundex)
        results = nb.select(sqlalchemy.or_(*conditions)).execute()
        results = [(x['nconst'], self._clean(self._rename('name_basics', dict(x)),
                                             ('ns_soundex', 'sn_soundex', 's_soundex')))
                   for x in results]
        results = scan_names(results, name)
        results = [x[1] for x in results]
        return results

