import "../config/api_config.dart";
import "../models/todo_item.dart";
import "api_client.dart";
import "mock_data.dart";

class TodoService {
  final ApiClient _client;

  TodoService(this._client);

  Future<List<TodoItem>> fetchTodos() async {
    if (ApiConfig.useMockData) {
      return List<TodoItem>.from(MockDataStore.todos);
    }
    final data = await _client.getList(ApiConfig.todos);
    return data
        .map((item) => TodoItem.fromJson(item as Map<String, dynamic>))
        .toList();
  }

  Future<List<TodoItem>> fetchTodayTodos() async {
    if (ApiConfig.useMockData) {
      final now = DateTime.now();
      final today = DateTime(now.year, now.month, now.day);
      final tomorrow = today.add(const Duration(days: 1));

      return MockDataStore.todos.where((todo) {
        if (todo.completed) {
          // If completed, only show if it was due today
          if (todo.dueDate == null) return false;
          return todo.dueDate!.isAfter(today.subtract(const Duration(milliseconds: 1))) &&
                 todo.dueDate!.isBefore(tomorrow);
        }
        
        // If not completed:
        // 1. No due date -> show
        // 2. Due today or before -> show
        if (todo.dueDate == null) return true;
        return todo.dueDate!.isBefore(tomorrow);
      }).toList();
    }
    final data = await _client.getList("${ApiConfig.todos}/today");
    return data
        .map((item) => TodoItem.fromJson(item as Map<String, dynamic>))
        .toList();
  }

  Future<TodoItem> createTodo(TodoItem todo) async {
    if (ApiConfig.useMockData) {
      final created = TodoItem(
        id: "todo-${DateTime.now().millisecondsSinceEpoch}",
        familyMemberId: todo.familyMemberId,
        title: todo.title,
        completed: todo.completed,
        dueDate: todo.dueDate,
      );
      MockDataStore.todos.add(created);
      return created;
    }
    final data = await _client.post(ApiConfig.todos, todo.toJson());
    return TodoItem.fromJson(data);
  }

  Future<TodoItem> updateTodo(TodoItem todo) async {
    if (ApiConfig.useMockData) {
      final index = MockDataStore.todos.indexWhere(
        (item) => item.id == todo.id,
      );
      if (index != -1) {
        MockDataStore.todos[index] = todo;
      }
      return todo;
    }
    final data = await _client.put(
      "${ApiConfig.todos}/${todo.id}",
      todo.toJson(),
    );
    return TodoItem.fromJson(data);
  }

  Future<void> deleteTodo(String id) async {
    if (ApiConfig.useMockData) {
      MockDataStore.todos.removeWhere((item) => item.id == id);
      return;
    }
    await _client.delete("${ApiConfig.todos}/$id");
  }
}