'use client'

import { useState, useEffect } from 'react'
import { signIn, useSession } from 'next-auth/react'
import { useRouter, useSearchParams } from 'next/navigation'
import { Button, Input } from '@/components/ui'
import { Mail, Lock, AlertCircle } from 'lucide-react'

export default function LoginPage() {
  const router = useRouter()
  const { data: session, status } = useSession()
  const searchParams = useSearchParams()
  const callbackUrl = searchParams.get('callbackUrl') || '/admin'
  
  const [email, setEmail] = useState('')
  const [password, setPassword] = useState('')
  const [error, setError] = useState('')
  const [isLoading, setIsLoading] = useState(false)

  // Si déjà connecté, rediriger vers /admin
  useEffect(() => {
    if (status === 'authenticated') {
      router.push(callbackUrl)
    }
  }, [status, router, callbackUrl])

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()
    setError('')
    setIsLoading(true)

    try {
      const result = await signIn('credentials', {
        email,
        password,
        redirect: false,
      })

      if (result?.error) {
        setError('Email ou mot de passe incorrect')
      } else {
        router.push(callbackUrl)
        router.refresh()
      }
    } catch (err) {
      setError('Une erreur est survenue')
    } finally {
      setIsLoading(false)
    }
  }

  if (status === 'loading') {
    return (
      <div className="min-h-screen flex items-center justify-center bg-gradient-to-br from-primary-50 via-white to-accent-50 dark:from-neutral-950 dark:via-neutral-900 dark:to-neutral-950">
        <div className="text-center">
          <div className="inline-flex items-center justify-center w-12 h-12 rounded-full bg-primary-100 dark:bg-primary-900/30 animate-spin mb-4">
            <div className="w-8 h-8 rounded-full border-2 border-primary-500 border-t-transparent"></div>
          </div>
          <p className="text-gray-600 dark:text-gray-400">Chargement...</p>
        </div>
      </div>
    )
  }

  return (
    <div className="min-h-screen flex items-center justify-center bg-gradient-to-br from-primary-50 via-white to-accent-50 dark:from-neutral-950 dark:via-neutral-900 dark:to-neutral-950 p-4">
      <div className="w-full max-w-md">
        {/* Logo */}
        <div className="text-center mb-8">
          <div className="w-16 h-16 mx-auto mb-4 rounded-2xl bg-gradient-to-br from-primary-500 to-accent-500 flex items-center justify-center shadow-lg">
            <span className="text-3xl">💰</span>
          </div>
          <h1 className="text-2xl font-display font-bold text-neutral-900 dark:text-white">
            Smart Budget CMS
          </h1>
          <p className="text-neutral-500 dark:text-neutral-400 mt-2">
            Connectez-vous pour accéder à l'administration
          </p>
        </div>

        {/* Form */}
        <div className="bg-white dark:bg-neutral-900 rounded-3xl shadow-soft border border-neutral-200 dark:border-neutral-800 p-8">
          <form onSubmit={handleSubmit} className="space-y-6">
            {error && (
              <div className="flex items-center gap-3 p-4 bg-red-50 dark:bg-red-900/20 rounded-xl text-red-700 dark:text-red-400">
                <AlertCircle className="h-5 w-5 flex-shrink-0" />
                <p className="text-sm">{error}</p>
              </div>
            )}

            <Input
              label="Email"
              type="email"
              value={email}
              onChange={(e) => setEmail(e.target.value)}
              placeholder="admin@smartbudget.fr"
              leftIcon={<Mail className="h-5 w-5" />}
              required
            />

            <Input
              label="Mot de passe"
              type="password"
              value={password}
              onChange={(e) => setPassword(e.target.value)}
              placeholder="••••••••"
              leftIcon={<Lock className="h-5 w-5" />}
              required
            />

            <Button
              type="submit"
              className="w-full"
              size="lg"
              isLoading={isLoading}
            >
              Se connecter
            </Button>
          </form>
        </div>

        <p className="text-center text-sm text-neutral-500 dark:text-neutral-400 mt-6">
          Retour au{' '}
          <a href="/" className="text-primary-600 dark:text-primary-400 hover:underline">
            site public
          </a>
        </p>
      </div>
    </div>
  )
}