import { useState } from 'react'
import { Navigate, useNavigate } from 'react-router-dom'
import { setInitialPasswordApi } from '../services/auth'
import { useAuth } from '../context/AuthContext'
import { homeFor } from '../config/roles'
import PasswordRules from '../components/PasswordRules'
import { isPasswordValid, PASSWORD_RULES_ERROR } from '../utils/passwordRules'

// Première connexion d'un employé créé par un admin : le mot de passe reçu
// par email est provisoire, il doit être remplacé avant tout accès.
export default function NouveauMotDePasse() {
  const navigate = useNavigate()
  const { user, login, logout } = useAuth()

  const [form, setForm] = useState({ password: '', confirmPassword: '' })
  const [showPassword, setShowPassword] = useState(false)
  const [error, setError] = useState('')
  const [loading, setLoading] = useState(false)

  if (!user) return <Navigate to="/connexion" replace />
  if (!user.mustChangePassword) return <Navigate to={homeFor(user)} replace />

  const handleChange = (e) => setForm({ ...form, [e.target.name]: e.target.value })

  const handleSubmit = async (e) => {
    e.preventDefault()
    setError('')

    if (!isPasswordValid(form.password)) {
      setError(PASSWORD_RULES_ERROR)
      return
    }
    if (form.password !== form.confirmPassword) {
      setError('Les deux mots de passe ne correspondent pas.')
      return
    }

    setLoading(true)
    try {
      await setInitialPasswordApi(form)
      const updatedUser = { ...user, mustChangePassword: false }
      login(updatedUser, localStorage.getItem('token'))
      navigate(homeFor(updatedUser), { replace: true })
    } catch (err) {
      if (err.status === 401) {
        logout()
        navigate('/connexion', { replace: true })
        return
      }
      setError(err.message)
      setLoading(false)
    }
  }

  const handleLogout = () => {
    logout()
    navigate('/connexion', { replace: true })
  }

  return (
    <div className="min-h-screen bg-white flex flex-col justify-center px-8 py-12 max-w-sm mx-auto">
      <div className="mb-8">
        <h1 className="text-4xl font-bold italic font-serif text-[#006B6B]">Nouveau mot de passe</h1>
        <p className="text-gray-500 mt-2 text-sm">
          Bienvenue {user.firstname} ! Vous vous êtes connecté avec un mot de passe provisoire.
          Choisissez votre propre mot de passe pour accéder à votre espace.
        </p>
      </div>

      {error && (
        <div className="mb-4 px-4 py-3 rounded-lg bg-red-50 border border-red-200 text-red-600 text-sm" role="alert">
          {error}
        </div>
      )}

      <form onSubmit={handleSubmit} className="space-y-5">
        <div>
          <label htmlFor="new-password" className="block text-sm font-medium text-gray-800 mb-1">
            Nouveau mot de passe <span className="text-gray-800">*</span>
          </label>
          <input
            type={showPassword ? 'text' : 'password'}
            id="new-password"
            name="password"
            value={form.password}
            onChange={handleChange}
            required
            autoComplete="new-password"
            aria-describedby="new-password-rules"
            placeholder="Votre nouveau mot de passe"
            className="w-full border border-gray-200 rounded-lg px-4 py-3 text-sm text-gray-700 placeholder-gray-500 focus:outline-none focus:ring-1 focus:ring-[#006B6B] focus:border-[#006B6B]"
          />
          <PasswordRules id="new-password-rules" password={form.password} />
        </div>

        <div>
          <label htmlFor="confirm-new-password" className="block text-sm font-medium text-gray-800 mb-1">
            Confirmer le mot de passe <span className="text-gray-800">*</span>
          </label>
          <input
            type={showPassword ? 'text' : 'password'}
            id="confirm-new-password"
            name="confirmPassword"
            value={form.confirmPassword}
            onChange={handleChange}
            required
            autoComplete="new-password"
            placeholder="Saisissez-le à nouveau"
            className="w-full border border-gray-200 rounded-lg px-4 py-3 text-sm text-gray-700 placeholder-gray-500 focus:outline-none focus:ring-1 focus:ring-[#006B6B] focus:border-[#006B6B]"
          />
        </div>

        <label className="flex items-center gap-2 cursor-pointer">
          <input
            type="checkbox"
            checked={showPassword}
            onChange={(e) => setShowPassword(e.target.checked)}
            className="w-5 h-5 accent-[#006B6B]"
          />
          <span className="text-xs text-gray-500">Afficher les mots de passe</span>
        </label>

        <button
          type="submit"
          disabled={loading}
          className="w-full bg-[#006B6B] hover:bg-[#005959] disabled:opacity-60 text-white font-medium py-3 rounded-lg transition-colors"
        >
          {loading ? 'Enregistrement…' : 'Enregistrer mon mot de passe'}
        </button>
      </form>

      <p className="text-center text-sm text-gray-500 mt-8">
        <button type="button" onClick={handleLogout} className="text-gray-700 font-medium hover:underline">
          Se déconnecter
        </button>
      </p>
    </div>
  )
}