export interface Task {
  id: number;
  title: string;
  description: string;
  status: "pending" | "in_progress" | "completed";
  priority: "low" | "medium" | "high";
  createdAt: string;
  updatedAt: string;
}

export interface APIResponse<T> {
  success: boolean;
  data?: T;
  error?: string;
}

const API_BASE = "/api";

export async function fetchTasks(): Promise<Task[]> {
  const res = await fetch(`${API_BASE}/tasks`);
  const json: APIResponse<Task[]> = await res.json();
  if (!json.success) throw new Error(json.error || "Failed to fetch tasks");
  return json.data || [];
}

export async function fetchTask(id: number): Promise<Task> {
  const res = await fetch(`${API_BASE}/tasks/${id}`);
  const json: APIResponse<Task> = await res.json();
  if (!json.success) throw new Error(json.error || "Failed to fetch task");
  return json.data!;
}

export async function createTask(
  task: Pick<Task, "title" | "description" | "priority" | "status">
): Promise<Task> {
  const res = await fetch(`${API_BASE}/tasks`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify(task),
  });
  const json: APIResponse<Task> = await res.json();
  if (!json.success) throw new Error(json.error || "Failed to create task");
  return json.data!;
}

export async function deleteTask(id: number): Promise<void> {
  const res = await fetch(`${API_BASE}/tasks/${id}`, {
    method: "DELETE",
  });
  const json: APIResponse<string> = await res.json();
  if (!json.success) throw new Error(json.error || "Failed to delete task");
}