shinkan-jinkendo/frontend/src/pages/VerifyPage.jsx

import { useState, useEffect } from 'react'
import { useSearchParams, useNavigate } from 'react-router-dom'
import { useAuth } from '../context/AuthContext'
import api from '../utils/api'

/**
 * E-Mail-Bestätigung (?token=) — gleiches Muster wie Mitai: SPA ruft /api/auth/verify/{token} auf.
 */
export default function VerifyPage() {
  const [searchParams] = useSearchParams()
  const token = searchParams.get('token')
  const navigate = useNavigate()
  const { checkAuth } = useAuth()

  const [status, setStatus] = useState('loading')
  const [error, setError] = useState(null)
  const [email, setEmail] = useState('')
  const [resending, setResending] = useState(false)
  const [resendSuccess, setResendSuccess] = useState(false)
  const [hasStarted, setHasStarted] = useState(false)

  useEffect(() => {
    if (hasStarted) return
    if (!token?.trim()) {
      setStatus('error')
      setError('Kein Verifikations-Token in der URL')
      return
    }
    setHasStarted(true)

    const run = async () => {
      try {
        const result = await api.verifyEmail(token.trim())
        if (result.token) {
          localStorage.setItem('authToken', result.token)
          await checkAuth()
        }
        setStatus('success')
        setTimeout(() => navigate('/', { replace: true }), 1500)
      } catch (err) {
        const msg = err.message || 'Verifizierung fehlgeschlagen'

        if (msg.includes('bereits bestätigt') || msg.includes('bereits verwendet')) {
          setStatus('already_verified')
          setError(msg)
          setTimeout(() => navigate('/login', { replace: true }), 3500)
        } else if (msg.includes('abgelaufen')) {
          setStatus('expired')
          setError(msg)
        } else {
          setStatus('error')
          setError(msg)
        }
      }
    }
    run()
  }, [token, hasStarted, checkAuth, navigate])

  const handleResend = async () => {
    if (!email.trim()) {
      setError('Bitte E-Mail-Adresse eingeben')
      return
    }
    setResending(true)
    setError(null)
    try {
      await api.resendVerification(email.trim().toLowerCase())
      setResendSuccess(true)
    } catch (err) {
      setError(err.message || 'Versand fehlgeschlagen')
    } finally {
      setResending(false)
    }
  }

  if (status === 'loading') {
    return (
      <div style={{ maxWidth: 420, margin: '0 auto', padding: '3rem 1rem', textAlign: 'center' }}>
        <div className="spinner" style={{ width: 48, height: 48, margin: '0 auto 1rem' }} />
        <h2 style={{ fontSize: '1.25rem' }}>E-Mail wird bestätigt…</h2>
        <p style={{ color: 'var(--text2)' }}>Einen Moment bitte.</p>
      </div>
    )
  }

  if (status === 'expired') {
    return (
      <div style={{ maxWidth: 420, margin: '0 auto', padding: '2rem 1rem' }}>
        <div className="card" style={{ marginBottom: '1rem' }}>
          <h2 style={{ fontSize: '1.15rem', marginBottom: '0.5rem' }}>Link abgelaufen</h2>
          <p style={{ color: 'var(--text2)', fontSize: '0.9rem', lineHeight: 1.5 }}>
            {error || 'Bitte fordere eine neue Bestätigungs-E-Mail an.'}
          </p>
          {resendSuccess ? (
            <p style={{ color: 'var(--accent)', fontWeight: 600, marginTop: '1rem' }}>E-Mail unterwegs — Postfach prüfen.</p>
          ) : (
            <>
              <label className="form-label" style={{ marginTop: '1rem' }}>
                Registrierte E-Mail
              </label>
              <input
                type="email"
                className="form-input"
                placeholder="du@beispiel.de"
                value={email}
                onChange={(e) => setEmail(e.target.value)}
                autoComplete="email"
              />
              {error && !resendSuccess && (
                <p style={{ color: 'var(--danger)', fontSize: '0.85rem', marginTop: '0.5rem' }}>{error}</p>
              )}
              <button
                type="button"
                className="btn btn-primary btn-full"
                style={{ marginTop: '0.85rem' }}
                disabled={resending || !email.trim()}
                onClick={handleResend}
              >
                {resending ? 'Sende…' : 'Erneut senden'}
              </button>
            </>
          )}
        </div>
        <button
          type="button"
          onClick={() => navigate('/login')}
          style={{
            background: 'none',
            border: 'none',
            color: 'var(--text3)',
            textDecoration: 'underline',
            cursor: 'pointer',
            width: '100%',
          }}
        >
          Zum Login
        </button>
      </div>
    )
  }

  if (status === 'already_verified') {
    return (
      <div style={{ maxWidth: 420, margin: '0 auto', padding: '2rem 1rem', textAlign: 'center' }}>
        <div className="card">
          <h2 style={{ fontSize: '1.15rem' }}>Schon erledigt</h2>
          <p style={{ color: 'var(--text2)', fontSize: '0.92rem', marginTop: '0.5rem' }}>
            {error || 'E-Mail bereits bestätigt — du kannst dich anmelden.'}
          </p>
          <p style={{ fontSize: '0.82rem', color: 'var(--text3)', marginTop: '0.75rem' }}>Weiterleitung zum Login…</p>
        </div>
      </div>
    )
  }

  if (status === 'error') {
    return (
      <div style={{ maxWidth: 420, margin: '0 auto', padding: '2rem 1rem', textAlign: 'center' }}>
        <div className="card" style={{ borderColor: 'var(--danger)' }}>
          <h2 style={{ fontSize: '1.15rem', color: 'var(--danger)' }}>Konnte nicht bestätigen</h2>
          <p style={{ color: 'var(--text2)', fontSize: '0.92rem', marginTop: '0.5rem' }}>{error}</p>
          <button type="button" className="btn btn-primary btn-full" style={{ marginTop: '1rem' }} onClick={() => navigate('/login')}>
            Zum Login
          </button>
        </div>
      </div>
    )
  }

  /* success */
  return (
    <div style={{ maxWidth: 420, margin: '0 auto', padding: '2rem 1rem', textAlign: 'center' }}>
      <div className="card">
        <h2 style={{ fontSize: '1.15rem', color: 'var(--accent-dark)', marginBottom: '0.5rem' }}>
          Bestätigung erfolgreich
        </h2>
        <p style={{ color: 'var(--text2)', fontSize: '0.92rem' }}>Du wirst weitergeleitet…</p>
        <div className="spinner" style={{ width: 32, height: 32, margin: '1rem auto 0' }} />
      </div>
    </div>
  )
}