import 'package:floor/floor.dart';

abstract class DatabaseMigration {
  /// 从版本1到版本2的迁移:添加productNamePy字段
  static Migration migration1To2 = Migration(1, 2, (database) async {
    // 先检查列是否存在，不存在才添加
    final result = await database.rawQuery(
      "PRAGMA table_info(supermarket_spu)",
    );
    bool columnExists = false;
    for (var column in result) {
      if (column['name'] == 'productNamePy') {
        columnExists = true;
        break;
      }
    }
    if (!columnExists) {
      await database
          .execute('ALTER TABLE supermarket_spu ADD COLUMN productNamePy TEXT');
    }
  });

  /// 从版本2到版本3的迁移:添加orderListJson字段
  static Migration migration2To3 = Migration(2, 3, (database) async {
    // 如果表不存在则创建，存在则校验列并补齐缺失项
    final tables = await database.rawQuery(
      "SELECT name FROM sqlite_master WHERE type='table' AND name='order_hold_bill'",
    );
    if (tables.isEmpty) {
      await database.execute('''
            CREATE TABLE IF NOT EXISTS order_hold_bill (
              id INTEGER PRIMARY KEY AUTOINCREMENT,
              sysType TEXT NOT NULL,
              carListJson TEXT,
              userJson TEXT,
              price INTEGER DEFAULT 0 NOT NULL,
              extraPrice INTEGER DEFAULT 0 NOT NULL,
              payPrice INTEGER DEFAULT 0 NOT NULL,
              createTime TEXT NOT NULL
            )
          ''');
      await database.execute(
        "CREATE INDEX IF NOT EXISTS idx_order_hold_bill_sysType ON order_hold_bill(sysType)",
      );
      await database.execute(
        "CREATE INDEX IF NOT EXISTS idx_order_hold_bill_createTime ON order_hold_bill(createTime)",
      );
    } else {
      final columns =
          await database.rawQuery("PRAGMA table_info(order_hold_bill)");
      bool hasSysType = false;
      bool hasCarListJson = false;
      bool hasOrderListJson = false;
      bool hasUserJson = false;
      bool hasPrice = false;
      bool hasExtraPrice = false;
      bool hasPayPrice = false;
      bool hasCreateTime = false;
      for (final c in columns) {
        final name = c['name'];
        if (name == 'sysType') hasSysType = true;
        if (name == 'carListJson') hasCarListJson = true;
        if (name == 'orderListJson') hasOrderListJson = true;
        if (name == 'userJson') hasUserJson = true;
        if (name == 'price') hasPrice = true;
        if (name == 'extraPrice') hasExtraPrice = true;
        if (name == 'payPrice') hasPayPrice = true;
        if (name == 'createTime') hasCreateTime = true;
      }
      if (!hasSysType) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN sysType TEXT',
        );
      }
      if (!hasCarListJson) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN carListJson TEXT',
        );
        if (hasOrderListJson) {
          // 旧列迁移到新列
          await database.execute(
            "UPDATE order_hold_bill SET carListJson = orderListJson WHERE carListJson IS NULL",
          );
        }
      }
      if (!hasUserJson) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN userJson TEXT',
        );
      }
      if (!hasPrice) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN price INTEGER DEFAULT 0 NOT NULL',
        );
      }
      if (!hasExtraPrice) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN extraPrice INTEGER DEFAULT 0 NOT NULL',
        );
      }
      if (!hasPayPrice) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN payPrice INTEGER DEFAULT 0 NOT NULL',
        );
      }
      if (!hasCreateTime) {
        await database.execute(
          'ALTER TABLE order_hold_bill ADD COLUMN createTime TEXT DEFAULT "" NOT NULL',
        );
      }
      await database.execute(
        "CREATE INDEX IF NOT EXISTS idx_order_hold_bill_sysType ON order_hold_bill(sysType)",
      );
      await database.execute(
        "CREATE INDEX IF NOT EXISTS idx_order_hold_bill_createTime ON order_hold_bill(createTime)",
      );
    }
  });

  /// 从版本3到版本4的迁移:添加为user_record表添加discountsList字段
  static Migration migration3To4 = Migration(3, 4, (database) async {
    final columns = await database.rawQuery("PRAGMA table_info(user_record)");
    bool hasDiscountsList = false;
    for (final c in columns) {
      if (c['name'] == 'discountsList') {
        hasDiscountsList = true;
        break;
      }
    }
    if (!hasDiscountsList) {
      await database
          .execute("ALTER TABLE user_record ADD COLUMN discountsList TEXT");
      await database.execute(
        "UPDATE user_record SET discountsList = '[]' WHERE discountsList IS NULL",
      );
    }
  });

  static Migration migration4To5 = Migration(4, 5, (database) async {
    final columns = await database.rawQuery("PRAGMA table_info(user_record)");
    bool hasDiscountsUpdateTime = false;
    for (final c in columns) {
      if (c['name'] == 'discountsUpdateTime') {
        hasDiscountsUpdateTime = true;
        break;
      }
    }
    if (!hasDiscountsUpdateTime) {
      await database.execute(
          "ALTER TABLE user_record ADD COLUMN discountsUpdateTime TEXT");
    }
  });

  static Migration migration5To6 = Migration(5, 6, (database) async {
    final columns = await database.rawQuery("PRAGMA table_info(canteen_spu)");
    bool hasIsPriceIncreased = false;
    for (final c in columns) {
      if (c['name'] == 'isPriceIncreased') {
        hasIsPriceIncreased = true;
        break;
      }
    }
    if (!hasIsPriceIncreased) {
      await database.execute(
        "ALTER TABLE canteen_spu ADD COLUMN isPriceIncreased INTEGER NOT NULL DEFAULT 0",
      );
    }
  });

  static Migration migration6To7 = Migration(6, 7, (database) async {
    final columns = await database.rawQuery("PRAGMA table_info(shop_card)");
    bool hasIsPriceIncreased = false;
    for (final c in columns) {
      if (c['name'] == 'isPriceIncreased') {
        hasIsPriceIncreased = true;
        break;
      }
    }
    if (!hasIsPriceIncreased) {
      await database.execute(
        "ALTER TABLE shop_card ADD COLUMN isPriceIncreased INTEGER NOT NULL DEFAULT 0",
      );
    }
  });

  static List<Migration> getDatabaseMigrations() {
    return [
      migration1To2,
      migration2To3,
      migration3To4,
      migration4To5,
      migration5To6,
      migration6To7,
    ];
  }
}