import { useState, useEffect } from 'react'
import { getPublicEvent, getGuestForEvent, submitEventRsvp } from '../api/api'
import './GuestSelfService.css'

/**
 * GuestSelfService
 *
 * Primary flow  : guest opens /guest/:eventId (from WhatsApp button)
 *   → page loads event details
 *   → guest enters phone number
 *   → backend looks up guest scoped to THAT event
 *   → guest fills RSVP form
 *   → POST /public/events/:eventId/rsvp  (only updates this event's record)
 *
 * Fallback flow : /guest with no eventId → plain phone lookup (legacy)
 */
function GuestSelfService({ eventId }) {
  // ─── Event state ──────────────────────────────────────────────────────
  const [event, setEvent] = useState(null)
  const [eventLoading, setEventLoading] = useState(false)
  const [eventError, setEventError] = useState('')

  // ─── Phone lookup state ──────────────────────────────────────────────
  const [phoneNumber, setPhoneNumber] = useState('')
  const [guest, setGuest] = useState(null)

  // ─── RSVP form state ─────────────────────────────────────────────────
  const [loading, setLoading] = useState(false)
  const [error, setError] = useState('')
  const [success, setSuccess] = useState(false)
  const [formData, setFormData] = useState({
    first_name: '',
    last_name: '',
    rsvp_status: 'invited',
    meal_preference: '',
    companion_count: 1,
  })

  // ─── Load event on mount ────────────────────────────────────────────
  useEffect(() => {
    if (!eventId) return
    setEventLoading(true)
    getPublicEvent(eventId)
      .then(setEvent)
      .catch(() => setEventError('האירוע לא נמצא.'))
      .finally(() => setEventLoading(false))
  }, [eventId])

  // ─── Phone lookup ────────────────────────────────────────────────────
  const handleLookup = async (e) => {
    e.preventDefault()
    setError('')
    setLoading(true)
    try {
      const guestData = await getGuestForEvent(eventId, phoneNumber)
      // Always present the form regardless of whether the guest was pre-imported.
      // Never pre-fill the name — the host may have saved a nickname in their
      // contacts that the guest should not see.
      setGuest(guestData)  // found:true or found:false — both show the RSVP form
      setFormData({
        first_name: '',  // guest enters their own name
        last_name: '',
        rsvp_status: guestData.rsvp_status || 'invited',
        meal_preference: guestData.meal_preference || '',
        companion_count: guestData.companion_count ?? 1,
      })
    } catch {
      // Only real network / server errors reach here
      setError('אירעה שגיאה. אנא נסה שוב.')
    } finally {
      setLoading(false)
    }
  }

  // ─── Submit RSVP ─────────────────────────────────────────────────────
  const handleSubmit = async (e) => {
    e.preventDefault()
    setError('')
    setLoading(true)
    try {
      await submitEventRsvp(eventId, { phone: phoneNumber, ...formData })
      setSuccess(true)
    } catch {
      setError('נכשל בשמירת הפרטים. אנא נסה שוב.')
    } finally {
      setLoading(false)
    }
  }

  const handleChange = (e) => {
    const { name, value, type, checked } = e.target
    setFormData((prev) => ({
      ...prev,
      [name]: type === 'checkbox' ? checked : type === 'number' ? parseInt(value, 10) || 1 : value,
    }))
  }

  // ─── Guest form field visibility (controlled by admin column settings) ──
  const guestFormFields = (() => {
    try {
      if (event?.guest_form_fields) return new Set(JSON.parse(event.guest_form_fields))
    } catch {}
    // Default: show all fields when no setting saved yet
    return new Set(['mealPref', 'companions'])
  })()
  const showMealPref    = guestFormFields.has('mealPref')
  // support both old key ('plusOne') and new key ('companions')
  const showCompanions  = guestFormFields.has('companions') || guestFormFields.has('plusOne')

  // ─── RSVP form (shared JSX) ──────────────────────────────────────────
  const rsvpForm = (
    <form onSubmit={handleSubmit} className="update-form">
      <div className="form-group">
        <label htmlFor="first_name">שם פרטי *</label>
        <input
          type="text"
          id="first_name"
          name="first_name"
          value={formData.first_name}
          onChange={handleChange}
          placeholder="השם הפרטי שלך"
          required
        />
      </div>

      <div className="form-group">
        <label htmlFor="last_name">שם משפחה</label>
        <input
          type="text"
          id="last_name"
          name="last_name"
          value={formData.last_name}
          onChange={handleChange}
          placeholder="שם המשפחה שלך"
        />
      </div>

      <div className="form-group">
        <label htmlFor="rsvp_status">סטטוס אישור הגעה *</label>
        <select
          id="rsvp_status"
          name="rsvp_status"
          value={formData.rsvp_status}
          onChange={handleChange}
          required
        >
          <option value="invited">עדיין לא בטוח</option>
          <option value="confirmed">כן, אהיה שם! 🎉</option>
          <option value="declined">מצטער, לא אוכל להגיע 😢</option>
        </select>
      </div>

      {formData.rsvp_status === 'confirmed' && (
        <>
          {showMealPref && (
            <div className="form-group">
              <label htmlFor="meal_preference">העדפת ארוחה</label>
              <select
                id="meal_preference"
                name="meal_preference"
                value={formData.meal_preference}
                onChange={handleChange}
              >
                <option value="">בחר ארוחה</option>
                <option value="chicken">עוף</option>
                <option value="beef">בשר בקר</option>
                <option value="fish">דג</option>
                <option value="vegetarian">צמחוני</option>
                <option value="vegan">טבעוני</option>
              </select>
            </div>
          )}

          {showCompanions && (
            <div className="form-group">
              <label htmlFor="companion_count">כמה תהיו? (כולל עצמך)</label>
              <input
                type="number"
                id="companion_count"
                name="companion_count"
                min="1"
                max="20"
                value={formData.companion_count}
                onChange={handleChange}
              />
            </div>
          )}
        </>
      )}

      <button type="submit" disabled={loading} className="btn btn-primary">
        {loading ? 'שומר...' : 'שמור אישור הגעה'}
      </button>
    </form>
  )

  // ─── Early returns ─────────────────────────────────────────────────────

  if (eventId && eventLoading) {
    return (
      <div className="guest-self-service" dir="rtl">
        <div className="service-container">
          <p className="subtitle">טוען פרטי אירוע...</p>
        </div>
      </div>
    )
  }

  if (eventId && eventError) {
    return (
      <div className="guest-self-service" dir="rtl">
        <div className="service-container">
          <h1>💒 אישור הגעה</h1>
          <div className="error-message">{eventError}</div>
        </div>
      </div>
    )
  }

  // ─── Event header (shown when we have event details) ─────────────────
  const eventHeader = event ? (
    <>
      <h1>💒 {event.name}</h1>
      {(event.partner1_name || event.partner2_name) && (
        <p className="subtitle">
          {[event.partner1_name, event.partner2_name].filter(Boolean).join(' ו')}
        </p>
      )}
      {event.date && <p className="subtitle">📅 {event.date}</p>}
      {event.venue && <p className="subtitle">📍 {event.venue}</p>}
      {event.event_time && <p className="subtitle">⏰ {event.event_time}</p>}
    </>
  ) : (
    <>
      <h1>💒 אישור הגעה לחתונה</h1>
      <p className="subtitle">עדכן את הגעתך והעדפותיך</p>
    </>
  )

  // ─── Main render ──────────────────────────────────────────────────────
  const hasImage = !!event?.invitation_image_url

  return (
    <div className={`guest-self-service${hasImage ? ' split-layout' : ''}`} dir="rtl">

      {/* Left panel — invitation image */}
      {hasImage && (
        <div className="invitation-image-panel">
          <img
            src={event.invitation_image_url}
            alt="הזמנה"
            className="invitation-image"
          />
        </div>
      )}

      {/* Right panel — form */}
      <div className="service-container">
        {eventHeader}

        {!guest ? (
          /* ── Step 1: phone lookup ── */
          <form onSubmit={handleLookup} className="lookup-form">
            <div className="form-group">
              <label htmlFor="phone">הזן מספר טלפון לאימות זהות</label>
              <input
                type="tel"
                id="phone"
                value={phoneNumber}
                onChange={(e) => setPhoneNumber(e.target.value)}
                placeholder="לדוגמה: 0501234567"
                required
              />
            </div>

            {error && <div className="error-message">{error}</div>}

            <button type="submit" disabled={loading} className="btn btn-primary">
              {loading ? 'מחפש...' : 'מצא את ההזמנה שלי'}
            </button>
          </form>
        ) : (
          /* ── Step 2: RSVP form ── */
          <div className="update-form-container">
            <div className="guest-info">
              <h2>שלום! 👋</h2>
              <p className="guest-note">אנא אשר את הגעתך והעדפותיך</p>
              {!success && (
                <button
                  onClick={() => { setGuest(null); setError(''); setSuccess(false) }}
                  className="btn-link"
                >
                  מספר טלפון אחר?
                </button>
              )}
            </div>

            {success && (
              <div className="success-message">
                ✓ תודה! אישור ההגעה שלך נשמר בהצלחה 🎉
              </div>
            )}
            {error && <div className="error-message">{error}</div>}
            {!success && rsvpForm}
          </div>
        )}
      </div>
    </div>
  )
}

export default GuestSelfService