// Revisions dropdown for a page: lists page_revisions; clicking one opens a modal
// with the rendered old content + a Restore action (PATCH body_md).
import { el } from '../dom.js';
import { api } from '../api.js';
import { marked } from '../vendor/marked.esm.js';
import DOMPurify from '../vendor/purify.es.mjs';

export function revisionsMenu(pageId, onRestore) {
  const wrap = el('div', { class: 'exp-menu' });
  const list = el('div', { class: 'exp-list rev-list' });

  const btn = el('button', {
    class: 'ghost',
    onclick: async (e) => { e.stopPropagation(); if (wrap.classList.toggle('open')) await load(); }
  }, 'Revisions ▾');

  async function load() {
    list.replaceChildren(el('div', { class: 'muted', style: { padding: '7px 10px' } }, 'Loading…'));
    let revs = [];
    try { revs = await api.get('/api/pages/' + pageId + '/revisions'); } catch { /* */ }
    list.replaceChildren();
    if (!revs.length) { list.appendChild(el('div', { class: 'muted', style: { padding: '7px 10px' } }, 'No earlier revisions.')); return; }
    revs.forEach(r => list.appendChild(el('button', { onclick: () => view(r) },
      new Date(r.created_at).toLocaleString() + (r.edited_by ? ` · ${r.edited_by}` : ''))));
  }

  function view(rev) {
    wrap.classList.remove('open');
    const body = el('div', { class: 'md-preview' });
    body.innerHTML = DOMPurify.sanitize(marked.parse(rev.body_md || ''));
    const modal = el('div', {
      class: 'rev-overlay',
      onclick: (e) => { if (e.target === modal) modal.remove(); }
    },
      el('div', { class: 'rev-modal' },
        el('div', { class: 'rev-modal-head' },
          el('span', {}, 'Revision · ' + new Date(rev.created_at).toLocaleString()),
          el('button', { class: 'ghost', onclick: () => modal.remove() }, 'Close')),
        body,
        el('div', { class: 'rev-modal-foot' },
          el('button', {
            class: 'primary',
            onclick: async () => {
              try {
                await api.patch('/api/pages/' + pageId, { body_md: rev.body_md });
                if (onRestore) onRestore(rev.body_md);
                modal.remove();
              } catch (e) { alert('Restore failed: ' + e.message); }
            }
          }, 'Restore this version'))));
    document.body.appendChild(modal);
  }

  wrap.append(btn, list);
  document.addEventListener('click', () => wrap.classList.remove('open'));
  return wrap;
}