import type { User } from "@/lib/types"

import { mockUsers } from "@/lib/mock"

export type RegisterInput = {
  username: string
  email: string
  password: string
  vcode?: string
}

export type LoginInput = {
  username: string
  password: string
}

function throwApiError(code: number, msg: string): never {
  throw { code, msg }
}

function nextUserId(): string {
  const maxId = Math.max(0, ...mockUsers.map((user) => Number.parseInt(user.id, 10) || 0))
  return String(maxId + 1)
}

export async function register(input: RegisterInput): Promise<User> {
  const username = input.username.trim()
  const email = input.email.trim()
  const password = input.password

  if (!username) throwApiError(400, "请输入用户名")
  if (!email) throwApiError(400, "请输入邮箱")
  if (!password || password.length < 6) throwApiError(400, "密码至少6位")

  const usernameTaken = mockUsers.some(
    (user) => user.username.toLowerCase() === username.toLowerCase(),
  )
  if (usernameTaken) throwApiError(400, "用户名已存在")

  const emailTaken = mockUsers.some((user) => user.email?.toLowerCase() === email.toLowerCase())
  if (emailTaken) throwApiError(400, "邮箱已被注册")

  await new Promise((r) => setTimeout(r, 500))

  const user: User = {
    id: nextUserId(),
    username,
    email,
    nickname: username,
    avatar: "/avatars/u1.jpg",
    role: "consumer",
    createdAt: new Date().toISOString(),
  }

  mockUsers.push(user)
  return user
}

export async function login(input: LoginInput): Promise<User> {
  const username = input.username.trim()
  const password = input.password

  if (!username) throwApiError(400, "请输入用户名")
  if (!password || password.length < 6) throwApiError(400, "密码至少6位")

  await new Promise((r) => setTimeout(r, 500))

  const user =
    mockUsers.find((u) => u.username.toLowerCase() === username.toLowerCase()) ??
    mockUsers.find((u) => u.email?.toLowerCase() === username.toLowerCase())

  if (!user) throwApiError(404, "用户不存在")
  return user
}

export async function resetPassword(input: {
  email: string
  vcode: string
  newPassword: string
}): Promise<void> {
  const email = input.email.trim()
  const vcode = input.vcode.trim()
  const newPassword = input.newPassword

  if (!email) throwApiError(400, "请输入邮箱")
  if (!vcode) throwApiError(400, "请输入验证码")
  if (!newPassword || newPassword.length < 8) throwApiError(400, "密码至少8位")

  await new Promise((r) => setTimeout(r, 500))

  const user = mockUsers.find((u) => u.email?.toLowerCase() === email.toLowerCase())
  if (!user) throwApiError(404, "用户不存在")
}