import 'package:flutter/foundation.dart';
import 'package:please_pay_me/core/state/async_value.dart';
import 'package:please_pay_me/data/api/api_client.dart';
import 'package:please_pay_me/data/models/job.dart';
import 'package:please_pay_me/data/repositories/repositories.dart';

class JobsController extends ChangeNotifier {
  JobsController({required JobRepository jobs}) : _jobs = jobs;

  final JobRepository _jobs;

  AsyncValue<List<Job>> _state = const AsyncValue.loading();
  bool _mutating = false;

  AsyncValue<List<Job>> get state => _state;
  bool get isMutating => _mutating;
  List<Job> get items => _state.valueOrNull ?? const [];

  /// Nearest payday across all jobs — shown on the overview screen.
  UpcomingPay? get nextPay {
    final pays = items.expand((job) => job.nextPays).toList()
      ..sort((a, b) => a.date.compareTo(b.date));
    return pays.isEmpty ? null : pays.first;
  }

  Future<void> load({bool silent = false}) async {
    if (!silent) {
      _state = const AsyncValue.loading();
      notifyListeners();
    }

    try {
      _state = AsyncValue.data(await _jobs.list());
    } on ApiException catch (error) {
      _state = AsyncValue.error(error.message);
    }
    notifyListeners();
  }

  Future<String?> create({
    required String name,
    required double salaryAmount,
    required List<int> payDays,
    required double firstPayPercent,
    required WeekendPolicy weekendPolicy,
  }) {
    return _mutate(
      () => _jobs.create(
        name: name,
        salaryAmount: salaryAmount,
        payDays: payDays,
        firstPayPercent: firstPayPercent,
        weekendPolicy: weekendPolicy,
      ),
    );
  }

  Future<String?> update({
    required int jobId,
    required String name,
    required double salaryAmount,
    required List<int> payDays,
    required double firstPayPercent,
    required WeekendPolicy weekendPolicy,
  }) {
    return _mutate(
      () => _jobs.update(
        jobId: jobId,
        name: name,
        salaryAmount: salaryAmount,
        payDays: payDays,
        firstPayPercent: firstPayPercent,
        weekendPolicy: weekendPolicy,
      ),
    );
  }

  Future<String?> delete(int jobId) => _mutate(() => _jobs.delete(jobId));

  Future<String?> _mutate(Future<void> Function() action) async {
    _mutating = true;
    notifyListeners();

    try {
      await action();
      await load(silent: true);
      return null;
    } on ApiException catch (error) {
      return error.message;
    } finally {
      _mutating = false;
      notifyListeners();
    }
  }
}