import 'dart:async';

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:mobile_scanner/mobile_scanner.dart';
import 'package:seshat/data/repositories/book_instance_repository.dart';
import 'package:seshat/data/repositories/book_repository.dart';
import 'package:seshat/data/repositories/owner_repository.dart';
import 'package:seshat/domain/models/bal.dart';
import 'package:seshat/domain/models/book.dart';
import 'package:seshat/domain/models/book_instance.dart';
import 'package:seshat/domain/models/owner.dart';
import 'package:seshat/utils/command.dart';
import 'package:seshat/utils/result.dart';

class AddViewModel extends ChangeNotifier {
  AddViewModel({
    required OwnerRepository ownerRepository,
    required BookRepository bookRepository,
    required BookInstanceRepository bookInstanceRepository,
  }) : _ownerRepository = ownerRepository,
       _bookRepository = bookRepository,
       _bookInstanceRepository = bookInstanceRepository {
    load = Command0(_load)..execute();
  }

  final OwnerRepository _ownerRepository;
  final BookRepository _bookRepository;
  final BookInstanceRepository _bookInstanceRepository;
  late final StreamSubscription sub;

  /*
 * ====================
 * =====[ OWNERS ]=====
 * ====================
*/

  Owner? _currentOwner;
  Owner? get currentOwner => _currentOwner;
  set currentOwner(Owner? owner) {
    _currentOwner = owner;
    notifyListeners();
  }

  List<Owner> _owners = [];
  List<Owner>? get owners => _owners;
  Future<Result<Owner>> addOwner(
    String firstName,
    String lastName,
    String contact,
  ) async {
    debugPrint("\n\n\n\n(2) TRANFERRING\n\n\n\n");
    final result = await _ownerRepository.addOwner(
      firstName,
      lastName,
      contact,
    );

    switch (result) {
      case Ok():
        final secondResult = await _ownerRepository.getOwners();

        switch (secondResult) {
          case Ok():
            debugPrint("\n\n\n${secondResult.value.length}");
            _owners = secondResult.value;
            debugPrint("\n\n\n${_owners.length}");
            _currentOwner = result.value;
            notifyListeners();
            return Result.ok(result.value);
          case Error():
            return Result.error(secondResult.error);
        }
      case Error():
        return Result.error(result.error);
    }
  }

  /*
 * ===================
 * =====[ PRICE ]=====
 * ===================
*/

  bool _askPrice = true;
  bool get askPrice => _askPrice;
  set askPrice(bool newValue) {
    _askPrice = newValue;
    notifyListeners();
  }

  /*
 * =================================
 * =====[ BOOKS AND INSTANCES ]=====
 * =================================
*/

  /// Sends an api request with a [bacorde], then gets the [Book] that was
  /// either created or retrieved. Sens the [Book] back wrapped in a [Result].
  Future<Result<Book>> scanBook(BarcodeCapture barcode) async {
    var ean = barcode.barcodes.first.rawValue!;
    var result = await _bookRepository.getBookByEAN(ean);
    return result;
  }

  Future<Result<BookInstance>> sendBook(
    Book book,
    Owner owner,
    Bal bal,
    double price,
  ) async {
    return await _bookInstanceRepository.sendBook(book, owner, bal, price);
  }

  /// Sends an api request with
  // Result<BookInstance> newBookInstance() {

  // };

  /*
 * =================================
 * =====[ COMMAND AND LOADING ]=====
 * =================================
*/

  late final Command0 load;
  bool isLoaded = false;

  Future<Result<void>> _load() async {
    return await _loadOwners();
  }

  Future<Result<void>> _loadOwners() async {
    final result = await _ownerRepository.getOwners();
    switch (result) {
      case Ok():
        _owners = result.value
          ..sort(
            (a, b) => "${a.firstName} ${a.lastName}".compareTo(
              "${b.firstName} ${b.lastName}",
            ),
          );
        isLoaded = true;
      case Error():
        debugPrint("Oupsie daysie, ${result.error}");
    }
    notifyListeners();

    return result;
  }

  @override
  void dispose() {
    sub.cancel();
    super.dispose();
  }
}