/**
 * Backup Manager module for ObsiGate.
 *
 * Full-page view to browse, preview, restore, and delete backups across vaults.
 * Accessible from the backup/diff viewer footer.
 */
import { api } from './auth.js';
import { showToast } from './ui.js';
import { safeCreateIcons } from './utils.js';

var state = { backups: [], filter: '', preview: null };

export function openBackupManager() {
  var area = document.getElementById('content-area');
  if (!area) return;
  area.innerHTML = '';

  var container = document.createElement('div');
  container.className = 'backup-manager';
  container.id = 'backup-manager';

  container.innerHTML =
    '<div class="backup-manager-header">' +
    '<h2><i data-lucide="archive" style="width:20px;height:20px"></i> Gestion des backups</h2>' +
    '<div class="backup-manager-actions">' +
    '<input type="text" id="bm-filter" class="backup-manager-filter" placeholder="Filtrer par fichier...">' +
    '<button class="backup-manager-btn" id="bm-refresh" title="Rafraichir"><i data-lucide="refresh-cw" style="width:14px;height:14px"></i></button>' +
    '</div>' +
    '</div>' +
    '<div class="backup-manager-stats" id="bm-stats"></div>' +
    '<div class="backup-manager-body">' +
    '<div class="backup-manager-list" id="bm-list"></div>' +
    '<div class="backup-manager-preview" id="bm-preview" style="display:none">' +
    '<div class="bm-preview-header">' +
    '<h3 id="bm-preview-title">Apercu</h3>' +
    '<button class="backup-manager-btn" id="bm-preview-close" title="Fermer"><i data-lucide="x" style="width:14px;height:14px"></i></button>' +
    '</div>' +
    '<pre class="bm-preview-content" id="bm-preview-content"></pre>' +
    '</div>' +
    '</div>';

  area.appendChild(container);
  safeCreateIcons();

  document.getElementById('bm-filter').addEventListener('input', function() {
    state.filter = this.value.toLowerCase();
    render();
  });
  document.getElementById('bm-refresh').addEventListener('click', load);
  document.getElementById('bm-preview-close').addEventListener('click', function() {
    document.getElementById('bm-preview').style.display = 'none';
  });

  state.preview = null;
  load();
}

async function load() {
  var list = document.getElementById('bm-list');
  list.innerHTML = '<div class="tree-loading" style="padding:2rem;text-align:center"><div class="loading-spinner" style="width:24px;height:24px;border-width:3px;margin:0 auto"></div></div>';

  try {
    var data = await api('/api/backups');
    state.backups = data.backups || [];
    updateStats(data);
    render();
  } catch (err) {
    list.innerHTML = '<div class="backup-manager-error">Erreur: ' + escapeHtml(err.message || 'Inconnue') + '</div>';
  }
}

function updateStats(data) {
  var stats = document.getElementById('bm-stats');
  if (!stats) return;
  var totalSize = formatSize(data.total_size_bytes || 0);
  stats.innerHTML =
    '<span class="bm-stat"><strong>' + data.total + '</strong> backups</span>' +
    '<span class="bm-stat"><strong>' + totalSize + '</strong> total</span>';
}

function render() {
  var list = document.getElementById('bm-list');
  if (!list) return;

  var filtered = state.backups;
  if (state.filter) {
    filtered = state.backups.filter(function(b) {
      return b.file.toLowerCase().indexOf(state.filter) !== -1 || b.vault.toLowerCase().indexOf(state.filter) !== -1;
    });
  }

  if (filtered.length === 0) {
    list.innerHTML = '<div class="backup-manager-empty">Aucun backup trouve.</div>';
    return;
  }

  var grouped = {};
  filtered.forEach(function(b) {
    if (!grouped[b.vault]) grouped[b.vault] = [];
    grouped[b.vault].push(b);
  });

  var html = '';
  var vaultNames = Object.keys(grouped).sort();
  vaultNames.forEach(function(vault) {
    var vaultBackups = grouped[vault];
    var vaultSize = vaultBackups.reduce(function(s, b) { return s + b.size; }, 0);

    html += '<div class="bm-vault-group">';
    html += '<div class="bm-vault-header">';
    html += '<h3 class="bm-vault-name"><i data-lucide="database" style="width:14px;height:14px"></i> ' + escapeHtml(vault) + '</h3>';
    html += '<span class="bm-vault-meta">' + vaultBackups.length + ' backups &middot; ' + formatSize(vaultSize) + '</span>';
    html += '<button class="bm-vault-purge" data-vault="' + escapeHtml(vault) + '" title="Supprimer tous les backups de ce vault"><i data-lucide="trash-2" style="width:14px;height:14px"></i> Vider</button>';
    html += '</div>';

    var byFile = {};
    vaultBackups.forEach(function(b) {
      if (!byFile[b.file]) byFile[b.file] = [];
      byFile[b.file].push(b);
    });

    var fileNames = Object.keys(byFile).sort();
    fileNames.forEach(function(file) {
      var backups = byFile[file];
      backups.sort(function(a, b) { return b.timestamp - a.timestamp; });
      var totalFileSize = backups.reduce(function(s, b) { return s + b.size; }, 0);

      html += '<div class="bm-file-group">';
      html += '<div class="bm-file-header">';
      html += '<span class="bm-file-name"><i data-lucide="file-text" style="width:14px;height:14px"></i> ' + escapeHtml(file) + '</span>';
      html += '<span class="bm-file-meta">' + backups.length + ' versions &middot; ' + formatSize(totalFileSize) + '</span>';
      html += '<button class="bm-file-purge" data-vault="' + escapeHtml(vault) + '" data-file="' + escapeHtml(file) + '" title="Supprimer tous les backups de ce fichier"><i data-lucide="trash-2" style="width:12px;height:12px"></i></button>';
      html += '</div>';

      html += '<div class="bm-backup-list">';
      backups.forEach(function(b) {
        var d = new Date(b.timestamp * 1000);
        var ds = d.getFullYear() + '-' + pad(d.getMonth()+1) + '-' + pad(d.getDate()) + ' ' + pad(d.getHours()) + ':' + pad(d.getMinutes());
        html += '<div class="bm-backup-item' + (state.preview === b.full_path ? ' active' : '') + '" data-path="' + escapeHtml(b.full_path) + '" data-vault="' + escapeHtml(b.vault) + '" data-file="' + escapeHtml(b.file) + '">';
        html += '<span class="bm-backup-date">' + ds + '</span>';
        html += '<span class="bm-backup-size">' + formatSize(b.size) + '</span>';
        html += '<div class="bm-backup-actions">';
        html += '<button class="bm-backup-preview" title="Apercu"><i data-lucide="eye" style="width:12px;height:12px"></i></button>';
        html += '<button class="bm-backup-restore" title="Restaurer cette version"><i data-lucide="rotate-ccw" style="width:12px;height:12px"></i></button>';
        html += '<button class="bm-backup-delete" data-path="' + escapeHtml(b.full_path) + '" title="Supprimer"><i data-lucide="x" style="width:12px;height:12px"></i></button>';
        html += '</div>';
        html += '</div>';
      });
      html += '</div>';
      html += '</div>';
    });

    html += '</div>';
  });

  list.innerHTML = html;
  safeCreateIcons();

  // Bind vault purge
  list.querySelectorAll('.bm-vault-purge').forEach(function(btn) {
    btn.addEventListener('click', function(e) {
      e.stopPropagation();
      if (confirm('Supprimer TOUS les backups du vault "' + btn.dataset.vault + '" ?')) {
        purgeVault(btn.dataset.vault);
      }
    });
  });

  // Bind file purge
  list.querySelectorAll('.bm-file-purge').forEach(function(btn) {
    btn.addEventListener('click', function(e) {
      e.stopPropagation();
      if (confirm('Supprimer TOUS les backups de "' + btn.dataset.file + '" ?')) {
        purgeFile(btn.dataset.vault, btn.dataset.file);
      }
    });
  });

  // Bind backup item clicks (preview) and action buttons
  list.querySelectorAll('.bm-backup-item').forEach(function(item) {
    item.addEventListener('click', function(e) {
      // Don't trigger preview if clicking an action button
      if (e.target.closest('button')) return;
      state.preview = item.dataset.path;
      render();
      previewBackup(item.dataset.path);
    });
  });

  // Bind action buttons
  list.querySelectorAll('.bm-backup-preview').forEach(function(btn) {
    btn.addEventListener('click', function(e) {
      e.stopPropagation();
      var item = btn.closest('.bm-backup-item');
      state.preview = item.dataset.path;
      render();
      previewBackup(item.dataset.path);
    });
  });

  list.querySelectorAll('.bm-backup-restore').forEach(function(btn) {
    btn.addEventListener('click', function(e) {
      e.stopPropagation();
      var item = btn.closest('.bm-backup-item');
      restoreBackup(item.dataset.vault, item.dataset.file);
    });
  });

  list.querySelectorAll('.bm-backup-delete').forEach(function(btn) {
    btn.addEventListener('click', function(e) {
      e.stopPropagation();
      if (confirm('Supprimer ce backup ?')) {
        deleteBackups([btn.dataset.path]);
      }
    });
  });
}

async function previewBackup(fpath) {
  var panel = document.getElementById('bm-preview');
  var content = document.getElementById('bm-preview-content');
  var title = document.getElementById('bm-preview-title');
  panel.style.display = 'block';
  content.textContent = t("common.loading");

  try {
    var data = await api('/api/backups/content?path=' + encodeURIComponent(fpath));
    content.textContent = data.content || '(fichier vide)';
    title.textContent = 'Apercu - ' + (data.name || '');
  } catch (err) {
    content.textContent = 'Erreur: ' + (err.message || 'Inconnue');
  }
}

async function restoreBackup(vault, file) {
  // Find the backup timestamp from the currently selected backup
  var item = document.querySelector('.bm-backup-item.active');
  if (!item) { showToast(t('backup.select_to_restore'), 'error'); return; }

  var backupPath = item.dataset.path;
  // Extract timestamp from the filename
  var parts = backupPath.replace(/\\/g, '/').split('/').pop().split('.');
  // The timestamp is the second-to-last component before .bak
  var ts = null;
  for (var i = parts.length - 1; i >= 0; i--) {
    if (parts[i] === 'bak' && i > 0 && /^\d+$/.test(parts[i-1])) {
      ts = parseInt(parts[i-1]);
      break;
    }
  }
  if (!ts) { showToast(t('backup.timestamp_not_found'), 'error'); return; }

  if (!confirm('Restaurer "' + file + '" a la version du backup selectionne ?\nLa version actuelle sera sauvegardee.')) return;

  try {
    var resp = await api('/api/file/' + encodeURIComponent(vault) + '/restore?path=' + encodeURIComponent(file), {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ version: ts }),
    });
    if (resp && resp.success) {
      showToast(t('backup.file_restored'), 'success');
      load();
    }
  } catch (err) {
    showToast('Erreur: ' + (err.message || 'Inconnue'), 'error');
  }
}

async function deleteBackups(paths) {
  try {
    var resp = await api('/api/backups/delete', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ paths: paths }),
    });
    showToast(resp.deleted + ' backup(s) supprime(s)', 'success');
    load();
  } catch (err) {
    showToast('Erreur: ' + err.message, 'error');
  }
}

async function purgeFile(vault, file) {
  try {
    var resp = await api('/api/backups/purge', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ vault: vault, file: file }),
    });
    showToast(resp.deleted + ' backup(s) supprime(s)', 'success');
    load();
  } catch (err) {
    showToast('Erreur: ' + err.message, 'error');
  }
}

async function purgeVault(vault) {
  try {
    var resp = await api('/api/backups/purge', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ vault: vault }),
    });
    showToast(resp.deleted + ' backup(s) supprime(s)', 'success');
    load();
  } catch (err) {
    showToast('Erreur: ' + err.message, 'error');
  }
}

function formatSize(bytes) {
  if (bytes < 1024) return bytes + ' o';
  if (bytes < 1024 * 1024) return (bytes / 1024).toFixed(1) + ' Ko';
  return (bytes / (1024 * 1024)).toFixed(1) + ' Mo';
}

function pad(n) { return String(n).padStart(2, '0'); }

function escapeHtml(str) {
  var div = document.createElement('div');
  div.textContent = str;
  return div.innerHTML;
}