"""Build the species-level catalog from a pinned PokéAPI CSV snapshot.

Run with --source-dir to reuse downloaded CSVs. Default downloads into a temporary
folder. Encounter absence is not evidence of trade/transfer/event exclusivity.
"""
import argparse
import concurrent.futures
import csv
import json
from pathlib import Path
import tempfile
import urllib.request

REVISION = '575291cdb197a7e3a320297be276c9de4ef8401a'
TABLES = ['pokemon', 'pokemon_species', 'pokemon_species_names', 'pokemon_types',
          'pokemon_stats', 'type_names', 'versions', 'version_names', 'version_groups',
          'pokemon_dex_numbers', 'pokedex_version_groups', 'pokemon_game_indices', 'encounters']


def build(directory):
    def rows(name):
        with (directory / f'{name}.csv').open() as f:
            return list(csv.DictReader(f))

    species = rows('pokemon_species')
    pokemon = rows('pokemon')
    species_for = {int(p['id']): int(p['species_id']) for p in pokemon}
    defaults = {int(p['species_id']): int(p['id']) for p in pokemon if p['is_default'] == '1'}
    names = {int(p['pokemon_species_id']): p['name'] for p in rows('pokemon_species_names') if p['local_language_id'] == '9'}
    type_names = {int(t['type_id']): t['name'] for t in rows('type_names') if t['local_language_id'] == '9'}
    types = {}
    for p in rows('pokemon_types'):
        types.setdefault(int(p['pokemon_id']), {})[int(p['slot'])] = type_names[int(p['type_id'])]
    stats = {}
    for p in rows('pokemon_stats'):
        stats.setdefault(int(p['pokemon_id']), {})[int(p['stat_id'])] = int(p['base_stat'])
    stat_fields = ['hp', 'attack', 'defense', 'specialAttack', 'specialDefense', 'speed']
    mons = []
    for s in species:
        number = int(s['id'])
        default = defaults[number]
        mons.append(dict(number=number, name=names[number], generation=int(s['generation_id']),
                         type1=types[default][1], type2=types[default].get(2),
                         **{name: stats[default][i + 1] for i, name in enumerate(stat_fields)}))

    groups = {int(g['id']): g for g in rows('version_groups')}
    versions = rows('versions')
    game_names = {int(v['version_id']): v['name'] for v in rows('version_names') if v['local_language_id'] == '9'}
    games = [dict(sourceId=int(v['id']), name=game_names.get(int(v['id']), v['identifier'].replace('-', ' ').title()),
                  generation=int(groups[int(v['version_group_id'])]['generation_id'])) for v in versions]
    for game, version in zip(games, versions):
        if version['identifier'].endswith('-japan'):
            game['name'] += ' (Japan)'
    versions_for_group = {}
    for v in versions:
        versions_for_group.setdefault(int(v['version_group_id']), []).append(int(v['id']))
    groups_for_dex = {}
    for d in rows('pokedex_version_groups'):
        groups_for_dex.setdefault(int(d['pokedex_id']), []).append(int(d['version_group_id']))
    entries = {}
    # Membership and internal game indices establish presence, not how it is obtained.
    for p in rows('pokemon_dex_numbers'):
        for group in groups_for_dex.get(int(p['pokedex_id']), []):
            for version in versions_for_group.get(group, []):
                entries[(int(p['species_id']), version)] = 'unknown'
    for p in rows('pokemon_game_indices'):
        if int(p['game_index']) > 0:
            entries[(species_for[int(p['pokemon_id'])], int(p['version_id']))] = 'unknown'
    for p in rows('encounters'):
        entries[(species_for[int(p['pokemon_id'])], int(p['version_id']))] = 'catchable'
    return dict(source={'repository': 'https://github.com/PokeAPI/pokeapi', 'revision': REVISION,
                        'scope': 'All species and game versions in this snapshot; default-form types/stats. Unknown means presence without confirmed encounter data. Missing pairs have no source record, not proven absence.'},
                pokemon=mons, games=games, entries=[[p, g, availability] for (p, g), availability in sorted(entries.items())])


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--source-dir', type=Path)
    args = parser.parse_args()
    with tempfile.TemporaryDirectory() as temporary:
        directory = args.source_dir or Path(temporary)
        if not args.source_dir:
            def download(table):
                url = f'https://raw.githubusercontent.com/PokeAPI/pokeapi/{REVISION}/data/v2/csv/{table}.csv'
                with urllib.request.urlopen(url, timeout=60) as response:
                    (directory / f'{table}.csv').write_bytes(response.read())
            with concurrent.futures.ThreadPoolExecutor(max_workers=4) as executor:
                list(executor.map(download, TABLES))
        catalog = build(directory)
    target = Path(__file__).resolve().parent.parent / 'data/pokemon-catalog.json'
    target.write_text(json.dumps(catalog, ensure_ascii=False, separators=(',', ':')) + '\n')
    print(f"Built {len(catalog['pokemon'])} species, {len(catalog['games'])} versions, {len(catalog['entries'])} entries")


if __name__ == '__main__':
    main()