import 'package:flutter/foundation.dart';
import '../models/todo.dart';

class ToDoProvider with ChangeNotifier {
  List<ToDo> _todos = [];

  List<ToDo> get todos => _todos;

  void addTask(ToDo todo) {
    _todos.add(todo);
    notifyListeners();
  }

  void removeTask(int index) {
    _todos.removeAt(index);
    notifyListeners();
  }

  void toggleCompletion(int index) {
    _todos[index].isCompleted = !_todos[index].isCompleted;
    notifyListeners();
  }

  // sorting logic for deadline
  void sortByDeadline() {
    _todos.sort((a, b) {
      if (a.deadline == null) return 1; // Tasks without deadline should come last
      if (b.deadline == null) return -1;
      return a.deadline!.compareTo(b.deadline!);
    });
    notifyListeners();
  }

  // sorting logic for priority
  void sortByPriority() {
    Map<String, int> priorityMap = {'High': 1, 'Medium': 2, 'Low': 3};
    _todos.sort((a, b) => priorityMap[a.priority]!.compareTo(priorityMap[b.priority]!));
    notifyListeners();
  }

  // sorting logic for staus
  void sortByStatus() {
    _todos.sort((a, b) => a.isCompleted ? 1 : -1); // Uncompleted first
    notifyListeners();
  }
}