import { useState, useEffect, useCallback } from 'react'
import api from '@/services/api'
import type { User } from '@/types'

interface AuthState {
  user: User | null
  token: string | null
  loading: boolean
}

export function useAuth() {
  const [state, setState] = useState<AuthState>({
    user: null,
    token: localStorage.getItem('token'),
    loading: true,
  })

  const fetchUser = useCallback(async () => {
    const token = localStorage.getItem('token')
    if (!token) {
      setState({ user: null, token: null, loading: false })
      return
    }
    try {
      const { data } = await api.get<User>('/auth/me')
      setState({ user: data, token, loading: false })
    } catch {
      localStorage.removeItem('token')
      setState({ user: null, token: null, loading: false })
    }
  }, [])

  useEffect(() => { fetchUser() }, [fetchUser])

  const login = async (username: string, password: string) => {
    const form = new URLSearchParams()
    form.append('username', username)
    form.append('password', password)
    const { data } = await api.post('/auth/token', form, {
      headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    })
    localStorage.setItem('token', data.access_token)
    setState((s) => ({ ...s, token: data.access_token }))
    await fetchUser()
  }

  const loginWithToken = async (token: string) => {
    localStorage.setItem('token', token)
    setState((s) => ({ ...s, token }))
    await fetchUser()
  }

  const logout = () => {
    localStorage.removeItem('token')
    setState({ user: null, token: null, loading: false })
  }

  return { ...state, login, loginWithToken, logout }
}