import 'package:drift/drift.dart';

import '../Entities/drift_database.dart';
import '../Services/database_service.dart';

/// Funktionen zum interagieren mit der Datenbank für die Transaktionen
class TransactionRepository {
  final AppDatabase _db = DatabaseService().database;

  /// Fügt eine neue Transaktion zur Datenbank hinzu
  Future<Transaction?> add(final TransactionsCompanion transaction) async {
    final int id = await _db.into(_db.transactions).insert(transaction);
    return find(id);
  }

  /// Entfernt eine Transaktion aus der Datenbank
  Future<int> remove(final Transaction transaction) => (_db.delete(
    _db.transactions,
  )..where((final t) => t.id.equals(transaction.id))).go();

  /// Sucht eine Transaktion anhand seiner Id aus der Datenbank
  Future<Transaction?> find(final int id) => (_db.select(
    _db.transactions,
  )..where((final t) => t.id.equals(id))).getSingleOrNull();

  /// Sucht Transaktionen anhand der gegebenen Parameter aus der Datenbank
  Future<List<Transaction>> findBy({
    final int? id,
    final String? name,
    final DateTime? date,
    final DateTime? dateBefore,
    final DateTime? dateAfter,
    final double? amount,
    final double? amountMin,
    final double? amountMax,
    final String? orderBy,
  }) {
    final SimpleSelectStatement<$TransactionsTable, Transaction> query = _db
        .select(_db.transactions);

    if (id != null) {
      query.where((final t) => t.id.equals(id));
    }

    if (name != null && name.isNotEmpty) {
      query.where((final t) => t.name.like('%$name%'));
    }

    if (date != null) {
      query.where((final t) => t.date.equals(date));
    }

    if (dateBefore != null) {
      query.where((final t) => t.date.isBiggerThanValue(dateBefore));
    }

    if (dateAfter != null) {
      query.where((final t) => t.date.isSmallerThanValue(dateAfter));
    }

    if (amount != null) {
      query.where((final t) => t.amount.equals(amount));
    }

    if (amountMin != null) {
      query.where((final t) => t.amount.isBiggerThanValue(amountMin));
    }

    if (amountMax != null) {
      query.where((final t) => t.amount.isSmallerThanValue(amountMax));
    }

    if (orderBy != null) {
      switch (orderBy) {
        case 'nameAsc':
          query.orderBy([(final t) => OrderingTerm.asc(t.name)]);
        case 'nameDesc':
          query.orderBy([(final t) => OrderingTerm.desc(t.name)]);
        case 'dateAsc':
          query.orderBy([(final t) => OrderingTerm.asc(t.date)]);
        case 'dateDesc':
          query.orderBy([(final t) => OrderingTerm.desc(t.date)]);
        case 'amountAsc':
          query.orderBy([(final t) => OrderingTerm.asc(t.amount)]);
        case 'amountDesc':
          query.orderBy([(final t) => OrderingTerm.desc(t.amount)]);
      }
    }

    return query.get();
  }
}