import { api } from '@/api/client'
import { setAuthTokenProvider } from '@/api/client'
import type { User } from '@/domain/types'

let cachedUser: User | null = null
let authToken: string | null = null
setAuthTokenProvider(() => authToken)

export async function currentUser(): Promise<User | null> {
  if (cachedUser) return cachedUser
  try {
    const res = await api.POST('/api/v1/auth/refresh', { params: { cookie: { user_id: 0 } } })
    if (!res.response.ok) return null
    // refresh returns legacy Person; adapt minimally to User shape
    const p = res.data as unknown as { id: number; name: string } | null
    cachedUser = p ? ({ id: p.id, email: '', displayName: p.name } as User) : null
  } catch (_) {
    cachedUser = null
  }
  return cachedUser
}

export async function login(username: string): Promise<User> {
  // Legacy compatibility shim: avoid network call; will be removed with new LoginPage
  cachedUser = { id: -1, email: '', displayName: username } as User
  return cachedUser
}

// New multitenant-ready API surface
export async function loginWithPassword(email: string, password: string): Promise<User> {
  const res = await api.POST('/api/v1/auth/login', { body: { email, password } })
  if (!res.response.ok) {
    const err = res.error
    throw ((err instanceof Error && err) || new Error(`${res.response.status} ${res.response.statusText || 'HTTP error'}`))
  }
  const token = res.data?.accessToken ?? null
  const user = res.data?.user ?? null
  if (!token || !user) throw new Error('Invalid token response')
  authToken = token
  cachedUser = user as User
  return cachedUser
}

export async function createAccount(email: string, displayName: string, password: string): Promise<User> {
  const res = await api.POST('/api/v1/auth/register', { body: { email, password, displayName } })
  if (!res.response.ok) {
    const err = res.error
    throw ((err instanceof Error && err) || new Error(`${res.response.status} ${res.response.statusText || 'HTTP error'}`))
  }
  const token = res.data?.accessToken ?? null
  const user = res.data?.user ?? null
  if (!token || !user) throw new Error('Invalid token response')
  authToken = token
  cachedUser = user as User
  return cachedUser
}

export async function handleGoogleLogin(_token: string): Promise<never> {
  // Placeholder until Google OAuth flow is wired
  throw new Error('handleGoogleLogin not implemented yet')
}

export async function logout(): Promise<void> {
  // Clear local cache; server session is cookie-based and will be refreshed on next call
  cachedUser = null
  authToken = null
}