feat(data): add instance-based SQLite local datasource

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

lib/data/datasources/pokemon_local_datasource.dart

@@ -0,0 +1,70 @@
+import 'package:sqflite_common/sqflite.dart';
+import '../../domain/entities/pokemon.dart';
+import '../dto/pokemon_dto.dart';
+
+/// Accès SQLite local au Pokédex. Schéma et migrations identiques à l'ancien PokedexDatabase.
+class PokemonLocalDataSource {
+  Database? _database;
+
+  Future<Database> _getDb() async {
+    _database ??= await openDatabase(
+      'pokedex.db',
+      version: 2,
+      onUpgrade: (db, oldVersion, newVersion) async {
+        if (oldVersion < 2) {
+          await db.execute('DROP TABLE IF EXISTS pokemon');
+          await db.execute(
+              'CREATE TABLE pokemon (id INTEGER PRIMARY KEY NOT NULL, name TEXT NOT NULL, type1 TEXT NOT NULL, type2 TEXT, hp INTEGER NOT NULL, atk INTEGER NOT NULL, def INTEGER NOT NULL, spd INTEGER NOT NULL, description TEXT, isCaught INTEGER NOT NULL DEFAULT 0, isSeen INTEGER NOT NULL DEFAULT 0)');
+        }
+      },
+      onCreate: (db, version) async {
+        await db.execute(
+            'CREATE TABLE IF NOT EXISTS pokemon (id INTEGER PRIMARY KEY NOT NULL, name TEXT NOT NULL, type1 TEXT NOT NULL, type2 TEXT, hp INTEGER NOT NULL, atk INTEGER NOT NULL, def INTEGER NOT NULL, spd INTEGER NOT NULL, description TEXT, isCaught INTEGER NOT NULL DEFAULT 0, isSeen INTEGER NOT NULL DEFAULT 0)');
+      },
+    );
+    return _database!;
+  }
+
+  Future<List<Pokemon>> getAll() async {
+    final db = await _getDb();
+    final rows = await db.query('pokemon');
+    return rows.map(PokemonDto.fromDb).toList();
+  }
+
+  Future<Pokemon?> getById(int id) async {
+    final db = await _getDb();
+    final rows = await db.query('pokemon', where: 'id = ?', whereArgs: [id]);
+    if (rows.isEmpty) return null;
+    return PokemonDto.fromDb(rows.first);
+  }
+
+  Future<void> saveAll(List<Pokemon> pokemons) async {
+    final db = await _getDb();
+    final batch = db.batch();
+    for (final p in pokemons) {
+      batch.insert('pokemon', PokemonDto.toDb(p),
+          conflictAlgorithm: ConflictAlgorithm.replace);
+    }
+    await batch.commit(noResult: true);
+  }
+
+  Future<void> update(Pokemon pokemon) async {
+    final db = await _getDb();
+    await db.update('pokemon', PokemonDto.toDb(pokemon),
+        where: 'id = ?', whereArgs: [pokemon.id]);
+  }
+
+  Future<int> caughtCount() async {
+    final db = await _getDb();
+    final result =
+        await db.rawQuery('SELECT COUNT(*) FROM pokemon WHERE isCaught = 1');
+    return result.isNotEmpty ? (result.first.values.first as int? ?? 0) : 0;
+  }
+
+  Future<int> seenCount() async {
+    final db = await _getDb();
+    final result =
+        await db.rawQuery('SELECT COUNT(*) FROM pokemon WHERE isSeen = 1');
+    return result.isNotEmpty ? (result.first.values.first as int? ?? 0) : 0;
+  }
+}