/* ============================================================
   BAN YARO — UI Helpers
   Alle UI-Interaktionen an einem Ort.
   Toast, Modal, Loading, Confirm — einmal gebaut, überall nutzbar.
   ============================================================ */

const UI = (() => {

  // ----------------------------------------------------------
  // TOAST
  // ----------------------------------------------------------
  const toast = (() => {
    const container = () => document.getElementById('toast-container');

    function show(message, type = 'default', duration = 3500) {
      const el = document.createElement('div');
      el.className = `toast${type !== 'default' ? ` toast-${type}` : ''}`;

      const icon = { success: '✓', danger: '✕', warning: '⚠', info: 'ℹ' }[type] || '';
      el.innerHTML = icon
        ? `<span style="font-size:1.1em">${icon}</span><span>${message}</span>`
        : `<span>${message}</span>`;

      container().appendChild(el);

      const timer = setTimeout(() => remove(el), duration);
      el.addEventListener('click', () => { clearTimeout(timer); remove(el); });
    }

    function remove(el) {
      el.classList.add('removing');
      const fallback = setTimeout(() => el.remove(), 300);
      el.addEventListener('animationend', () => { clearTimeout(fallback); el.remove(); }, { once: true });
    }

    return {
      show,
      success: (msg, dur)  => show(msg, 'success', dur),
      error:   (msg, dur)  => show(msg, 'danger',  dur || 5000),
      warning: (msg, dur)  => show(msg, 'warning', dur),
      info:    (msg, dur)  => show(msg, 'info',    dur),
    };
  })();

  // ----------------------------------------------------------
  // MODAL
  // ----------------------------------------------------------
  const modal = (() => {
    let _current = null;

    function open({ title, body, footer, onClose } = {}) {
      close(); // vorheriges schließen

      const overlay = document.createElement('div');
      overlay.className = 'modal-overlay';
      overlay.innerHTML = `
        <div class="modal" role="dialog" aria-modal="true">
          <div class="modal-handle"></div>
          ${title ? `
            <div class="modal-header">
              <span class="modal-title">${title}</span>
              <button class="btn btn-ghost btn-icon modal-close-btn" aria-label="Schließen">✕</button>
            </div>
          ` : ''}
          <div class="modal-body">${body || ''}</div>
          ${footer ? `<div class="modal-footer">${footer}</div>` : ''}
        </div>
      `;

      overlay.querySelector('.modal-close-btn')?.addEventListener('click', close);
      overlay.addEventListener('click', e => { if (e.target === overlay) close(); });

      document.getElementById('modal-container').appendChild(overlay);
      document.body.style.overflow = 'hidden';
      _current = { overlay, onClose };

      return overlay.querySelector('.modal');
    }

    function close() {
      if (!_current) return;
      _current.onClose?.();
      _current.overlay.remove();
      document.body.style.overflow = '';
      _current = null;
    }

    // Bestätigungsdialog
    function confirm({ title, message, confirmText = 'OK', cancelText = 'Abbrechen',
                        danger = false } = {}) {
      return new Promise(resolve => {
        const m = open({
          title,
          body: `<p style="color:var(--c-text-secondary)">${message}</p>`,
          footer: `
            <button class="btn btn-secondary" id="modal-cancel">${cancelText}</button>
            <button class="btn ${danger ? 'btn-danger' : 'btn-primary'}" id="modal-confirm">
              ${confirmText}
            </button>
          `,
          onClose: () => resolve(false),
        });
        m.parentElement.querySelector('#modal-cancel').addEventListener('click', () => {
          resolve(false); close();
        });
        m.parentElement.querySelector('#modal-confirm').addEventListener('click', () => {
          resolve(true); close();
        });
      });
    }

    return { open, close, confirm };
  })();

  // ----------------------------------------------------------
  // LOADING STATE für Buttons
  // ----------------------------------------------------------
  function setLoading(btn, loading) {
    if (loading) {
      btn._originalContent = btn.innerHTML;
      btn.innerHTML = '<span class="spinner spinner-sm"></span>';
      btn.disabled = true;
    } else {
      btn.innerHTML = btn._originalContent || btn.innerHTML;
      btn.disabled = false;
    }
  }

  // ----------------------------------------------------------
  // ASYNC BUTTON: Button-Click → Loader → Ergebnis → Toast
  // Verwendung: UI.asyncButton(btn, async () => { await API.something() })
  // ----------------------------------------------------------
  async function asyncButton(btn, fn, { successMsg, errorMsg } = {}) {
    setLoading(btn, true);
    try {
      const result = await fn();
      if (successMsg) toast.success(successMsg);
      return result;
    } catch (err) {
      const msg = errorMsg || err.message || 'Ein Fehler ist aufgetreten.';
      toast.error(msg);
      throw err;
    } finally {
      setLoading(btn, false);
    }
  }

  // ----------------------------------------------------------
  // FORMULAR-HELPER
  // ----------------------------------------------------------
  function formData(form) {
    const data = {};
    new FormData(form).forEach((v, k) => { data[k] = v; });
    return data;
  }

  function setFormError(form, fieldName, message) {
    const field = form.querySelector(`[name="${fieldName}"]`);
    if (!field) return;
    field.classList.add('is-invalid');
    let hint = field.parentElement.querySelector('.form-error');
    if (!hint) {
      hint = document.createElement('span');
      hint.className = 'form-error';
      field.parentElement.appendChild(hint);
    }
    hint.textContent = message;
  }

  function clearFormErrors(form) {
    form.querySelectorAll('.is-invalid').forEach(el => el.classList.remove('is-invalid'));
    form.querySelectorAll('.form-error').forEach(el => el.remove());
  }

  // ----------------------------------------------------------
  // LEERER ZUSTAND (Empty State)
  // ----------------------------------------------------------
  function emptyState({ icon, title, text, action } = {}) {
    return `
      <div class="empty-state">
        ${icon ? `<div class="empty-state-icon">${icon}</div>` : ''}
        ${title ? `<div class="empty-state-title">${title}</div>` : ''}
        ${text  ? `<div class="empty-state-text">${text}</div>` : ''}
        ${action ? `<div style="margin-top:var(--space-4)">${action}</div>` : ''}
      </div>
    `;
  }

  // ----------------------------------------------------------
  // DATUM-FORMATIERUNG (Deutsch, relativ)
  // ----------------------------------------------------------
  const time = (() => {
    const fmt = new Intl.RelativeTimeFormat('de', { numeric: 'auto' });
    const fmtDate = new Intl.DateTimeFormat('de-DE', {
      day: 'numeric', month: 'long', year: 'numeric'
    });
    const fmtDateShort = new Intl.DateTimeFormat('de-DE', {
      day: 'numeric', month: 'short'
    });

    function relative(dateStr) {
      const diff = (new Date(dateStr) - Date.now()) / 1000;
      const abs  = Math.abs(diff);
      if (abs < 60)   return fmt.format(Math.round(diff), 'second');
      if (abs < 3600) return fmt.format(Math.round(diff / 60), 'minute');
      if (abs < 86400)return fmt.format(Math.round(diff / 3600), 'hour');
      if (abs < 604800) return fmt.format(Math.round(diff / 86400), 'day');
      return fmtDate.format(new Date(dateStr));
    }

    return {
      relative,
      format:      d => fmtDate.format(new Date(d)),
      formatShort: d => fmtDateShort.format(new Date(d)),
    };
  })();

  // ----------------------------------------------------------
  // FOTO-VORSCHAU (Input[type=file] → img)
  // ----------------------------------------------------------
  function setupPhotoPreview(input, imgEl) {
    input.addEventListener('change', () => {
      const file = input.files[0];
      if (!file) return;
      const reader = new FileReader();
      reader.onload = e => { imgEl.src = e.target.result; };
      reader.readAsDataURL(file);
    });
  }

  // ----------------------------------------------------------
  // SCROLL TO TOP der Seite
  // ----------------------------------------------------------
  function scrollTop() {
    document.getElementById('page-content')?.scrollTo({ top: 0, behavior: 'smooth' });
  }

  // ----------------------------------------------------------
  // SKELETON LOADER (Platzhalter während Laden)
  // ----------------------------------------------------------
  function skeleton(lines = 3) {
    return Array.from({ length: lines }, (_, i) => `
      <div style="height:${i === 0 ? 20 : 14}px; width:${70 + Math.random() * 30}%;
           background:var(--c-surface-2); border-radius:var(--radius-sm);
           margin-bottom:var(--space-2); animation:skeleton-pulse 1.5s ease infinite">
      </div>
    `).join('') + `
      <style>
        @keyframes skeleton-pulse {
          0%,100% { opacity:1 } 50% { opacity:0.4 }
        }
      </style>
    `;
  }

  // Öffentliche API
  return {
    toast, modal,
    setLoading, asyncButton,
    formData, setFormError, clearFormErrors,
    emptyState, time,
    setupPhotoPreview, scrollTop, skeleton,
  };

})();