// frontend/src/api/todos.ts
export interface Todo {
  id: string
  title: string
  body: string | null
  url: string | null
  domains: string[]
  category: string | null
  tags: string[]
  status: 'pending' | 'done' | 'cancelled'
  priority: 'low' | 'medium' | 'high'
  due_date: string | null
  postponed_count: number
  photo_path: string | null
  gps_lat: number | null
  gps_lng: number | null
  created_at: string
  updated_at: string | null
  owner_id: string | null
}

export interface TodoCreate {
  title: string
  body?: string
  url?: string
  domain?: string
  domains?: string[]
  category?: string
  tags?: string[]
  status?: 'pending' | 'done' | 'cancelled'
  priority?: 'low' | 'medium' | 'high'
  due_date?: string
  photo_path?: string
  gps_lat?: number
  gps_lng?: number
}

export interface TodoUpdate {
  title?: string
  body?: string
  url?: string
  domain?: string
  domains?: string[]
  category?: string
  tags?: string[]
  status?: 'pending' | 'done' | 'cancelled'
  priority?: 'low' | 'medium' | 'high'
  due_date?: string
  photo_path?: string
  gps_lat?: number
  gps_lng?: number
}

export interface TodoFilters {
  domain?: string
  status?: string
  priority?: string
  tag?: string
  due_after?: string
  due_before?: string
}

const BASE = '/api/todos'

async function handleResponse<T>(res: Response): Promise<T> {
  if (!res.ok) throw new Error(`${res.status} ${res.statusText}`)
  if (res.status === 204) return undefined as T
  return res.json() as Promise<T>
}

export async function fetchTodos(filters?: TodoFilters): Promise<Todo[]> {
  const qs = new URLSearchParams()
  if (filters?.domain) qs.set('domain', filters.domain)
  if (filters?.status !== undefined) qs.set('status', filters.status)
  if (filters?.priority) qs.set('priority', filters.priority)
  if (filters?.tag) qs.set('tag', filters.tag)
  if (filters?.due_after) qs.set('due_after', filters.due_after)
  if (filters?.due_before) qs.set('due_before', filters.due_before)
  const res = await fetch(`${BASE}/?${qs}`)
  return handleResponse<Todo[]>(res)
}

export async function createTodo(data: TodoCreate): Promise<Todo> {
  const res = await fetch(`${BASE}/`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(data),
  })
  return handleResponse<Todo>(res)
}

export async function updateTodo(id: string, data: TodoUpdate): Promise<Todo> {
  const res = await fetch(`${BASE}/${id}`, {
    method: 'PATCH',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(data),
  })
  return handleResponse<Todo>(res)
}

export async function deleteTodo(id: string): Promise<void> {
  const res = await fetch(`${BASE}/${id}`, { method: 'DELETE' })
  await handleResponse<void>(res)
}

export async function postponeTodo(id: string, days: 1 | 7): Promise<Todo> {
  const res = await fetch(`${BASE}/${id}/postpone`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ days }),
  })
  return handleResponse<Todo>(res)
}