/**
 * Gestion du formulaire de contact en modal avec envoi AJAX.
 * Protections : CSRF, honeypot, limitation de débit côté session.
 */
class ContactForm {
  /**
   * @param {HTMLFormElement} form
   * @param {HTMLElement}     modal
   * @param {string}          url    - endpoint POST
   * @param {string}          csrfToken
   */
  constructor(form, modal, url, csrfToken) {
    this.form      = form;
    this.modal     = modal;
    this.url       = url;
    this.csrfToken = csrfToken;

    this.overlay  = modal.querySelector('#contact-overlay');
    this.btnClose = modal.querySelector('#contact-modal-close');
    this.btnOpen  = document.querySelector('#open-contact-modal');
    this.submit   = form.querySelector('#contact-submit');
    this.success  = modal.querySelector('#contact-success');
    this.globalErr = modal.querySelector('#contact-global-error');

    this._bindEvents();
  }

  // ── Initialisation ─────────────────────────────────────────────────────────

  _bindEvents() {
    // Ouvrir
    if (this.btnOpen) {
      this.btnOpen.addEventListener('click', () => {
        this._setPropertyId(this.btnOpen.dataset.property);
        this.open();
      });
    }

    // Fermer
    if (this.btnClose) this.btnClose.addEventListener('click', () => this.close());
    if (this.overlay)  this.overlay.addEventListener('click', () => this.close());

    // Clavier
    document.addEventListener('keydown', (e) => {
      if (e.key === 'Escape' && !this.modal.hidden) this.close();
    });

    // Soumission
    this.form.addEventListener('submit', (e) => this._handleSubmit(e));

    // Nettoyage des erreurs à la saisie
    this.form.querySelectorAll('input, textarea').forEach((el) => {
      el.addEventListener('input', () => this._clearFieldError(el.name));
    });
  }

  // ── API publique ───────────────────────────────────────────────────────────

  open() {
    this._resetForm();
    this.modal.hidden = false;
    document.body.style.overflow = 'hidden';
    this.form.querySelector('#id_name')?.focus();
  }

  close() {
    this.modal.hidden = true;
    document.body.style.overflow = '';
  }

  // ── Soumission ─────────────────────────────────────────────────────────────

  async _handleSubmit(e) {
    e.preventDefault();
    if (!this._validateLocal()) return;

    this._setLoading(true);
    this._hideGlobalError();

    const formData = new FormData(this.form);

    try {
      const response = await fetch(this.url, {
        method: 'POST',
        body: formData,
        headers: {
          'X-Requested-With': 'XMLHttpRequest',
          'X-CSRFToken': this.csrfToken,
        },
      });

      if (!response.ok) throw new Error(`HTTP ${response.status}`);
      const data = await response.json();

      if (data.success) {
        this._showSuccess();
      } else if (data.errors) {
        this._showFieldErrors(data.errors);
      } else if (data.error) {
        this._showGlobalError(data.error);
      }
    } catch (err) {
      this._showGlobalError(
        (window.I18N?.networkError) || 'Une erreur est survenue. Veuillez réessayer.'
      );
    } finally {
      this._setLoading(false);
    }
  }

  // ── Validation locale légère ───────────────────────────────────────────────

  _validateLocal() {
    let valid = true;
    const name  = this.form.querySelector('#id_name');
    const email = this.form.querySelector('#id_email');
    const msg   = this.form.querySelector('#id_message');

    if (!name.value.trim()) {
      this._setFieldError('name', name.required ? 'Ce champ est requis.' : '');
      valid = false;
    }
    if (!email.value.trim() || !email.value.includes('@')) {
      this._setFieldError('email', 'Adresse email invalide.');
      valid = false;
    }
    if (!msg.value.trim() || msg.value.trim().length < 10) {
      this._setFieldError('message', 'Votre message est trop court.');
      valid = false;
    }
    return valid;
  }

  // ── Utilitaires ────────────────────────────────────────────────────────────

  _setPropertyId(id) {
    const input = this.form.querySelector('#id_property_id');
    if (input) input.value = id || '';
  }

  _setLoading(loading) {
    if (!this.submit) return;
    const i18n = window.I18N || {};
    this.submit.disabled = loading;
    this.submit.textContent = loading
      ? (i18n.sending || 'Envoi en cours…')
      : (i18n.send    || 'Envoyer');
  }

  _showSuccess() {
    this.form.hidden   = true;
    this.success.hidden = false;
  }

  _resetForm() {
    this.form.reset();
    this.form.hidden    = false;
    this.success.hidden = true;
    this._hideGlobalError();
    this.form.querySelectorAll('.field-error').forEach(el => { el.textContent = ''; });
  }

  _setFieldError(name, msg) {
    const el = this.form.querySelector(`.field-error[data-field="${name}"]`);
    if (el) el.textContent = msg;
  }

  _clearFieldError(name) {
    this._setFieldError(name, '');
  }

  _showFieldErrors(errors) {
    for (const [field, msgs] of Object.entries(errors)) {
      const list = Array.isArray(msgs) ? msgs : [msgs];
      this._setFieldError(field, list.join(' '));
    }
  }

  _showGlobalError(msg) {
    if (!this.globalErr) return;
    this.globalErr.textContent = msg;
    this.globalErr.hidden = false;
  }

  _hideGlobalError() {
    if (this.globalErr) this.globalErr.hidden = true;
  }
}