'use client'

import { useEffect, useState } from 'react'

type AuthUser = { id: string; email?: string | null }

const AUTH_EVENT = 'letschat-auth-refresh'

export const emitAuthChanged = () => {
  if (typeof window !== 'undefined') {
    window.dispatchEvent(new Event(AUTH_EVENT))
  }
}

export function useAuth() {
  const [user, setUser] = useState<AuthUser | null>(null)
  const [loading, setLoading] = useState(true)

  const refresh = async () => {
    try {
      // include Authorization header from localStorage fallback if present
      const headers: Record<string, string> = { 'Content-Type': 'application/json' }
      if (typeof window !== 'undefined') {
        const fallback = window.localStorage.getItem('letschat_session')
        if (fallback) headers['Authorization'] = `Bearer ${fallback}`
      }
      const res = await fetch('/api/auth/me', { cache: 'no-store', credentials: 'include', headers })
      const data = await res.json().catch(() => ({}))
      setUser(data?.user ? { id: data.user.id, email: data.user.email } : null)
    } catch {
      setUser(null)
    } finally {
      setLoading(false)
    }
  }

  useEffect(() => {
    refresh()
    const listener = () => {
      setLoading(true)
      refresh()
    }
    window.addEventListener(AUTH_EVENT, listener)
    return () => window.removeEventListener(AUTH_EVENT, listener)
  }, [])

  return { user, loading, refresh }
}