'use strict';

// ---------------------------------------------------------------------------
// 批量选择 / 批量下载 / 批量删除 (依赖 app.js 的 consts: checkAll, checkAllWrap,
// batchBtn, batchCount, batchDeleteBtn, batchDeleteCount, filesList, toast)
// 用 var 顶层声明, 跨文件共享 (classic <script> 加载顺序: app.js → helpers.js → batch.js).
// ---------------------------------------------------------------------------
var selectedFiles = new Set();

function onCheckChange(name, checked) {
  if (checked) selectedFiles.add(name);
  else selectedFiles.delete(name);
  updateBatchUI();
}

function updateBatchUI() {
  const n = selectedFiles.size;
  batchCount.textContent = n;
  batchBtn.style.display = n > 0 ? 'inline-block' : 'none';
  batchDeleteCount.textContent = n;
  batchDeleteBtn.style.display = n > 0 ? 'inline-block' : 'none';

  const checks = filesList.querySelectorAll('.file-check');
  if (checks.length === 0) {
    checkAllWrap.style.display = 'none';
    checkAll.checked = false;
    checkAll.indeterminate = false;
    return;
  }
  checkAllWrap.style.display = 'inline-flex';
  let checkedCount = 0;
  checks.forEach(c => { if (c.checked) checkedCount++; });
  checkAll.checked = checkedCount === checks.length;
  checkAll.indeterminate = checkedCount > 0 && checkedCount < checks.length;
}

checkAll.addEventListener('change', () => {
  const want = checkAll.checked;
  filesList.querySelectorAll('.file-check').forEach(c => {
    if (c.checked !== want) {
      c.checked = want;
      const name = c.dataset.name;
      if (want) selectedFiles.add(name);
      else selectedFiles.delete(name);
    }
  });
  updateBatchUI();
});

batchBtn.addEventListener('click', async () => {
  if (selectedFiles.size === 0) return;
  const names = [...selectedFiles];
  batchBtn.disabled = true;
  const restore = () => { batchBtn.disabled = false; batchBtn.textContent = `批量下载 (${selectedFiles.size})`; };
  batchBtn.textContent = '打包中...';
  try {
    const r = await fetch('/download-zip', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ files: names }),
    });
    if (!r.ok) {
      let msg = 'HTTP ' + r.status;
      try { msg = (await r.json()).error || msg; } catch {}
      throw new Error(msg);
    }
    // 从 Content-Disposition 取 server 起的 zip 文件名, 兜底 'files.zip'
    let fname = 'files.zip';
    const cd = r.headers.get('Content-Disposition') || '';
    const m = cd.match(/filename="?([^";]+)"?/);
    if (m) fname = m[1];
    const blob = await r.blob();
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url; a.download = fname;
    document.body.appendChild(a); a.click(); document.body.removeChild(a);
    setTimeout(() => URL.revokeObjectURL(url), 1000);
    toast(`已下载 ${names.length} 个文件`, 'success');
  } catch (e) {
    toast('批量下载失败: ' + e.message, 'error');
  } finally {
    restore();
  }
});

batchDeleteBtn.addEventListener('click', async () => {
  if (selectedFiles.size === 0) return;
  const names = [...selectedFiles];
  if (!confirm(`确定删除选中的 ${names.length} 个文件吗? 该操作不可恢复.`)) return;
  batchDeleteBtn.disabled = true;
  const restore = () => { batchDeleteBtn.disabled = false; batchDeleteBtn.textContent = `批量删除 (${selectedFiles.size})`; };
  batchDeleteBtn.textContent = '删除中...';
  try {
    const r = await fetch('/files-delete', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ files: names }),
    });
    if (!r.ok) {
      let msg = 'HTTP ' + r.status;
      try { msg = (await r.json()).error || msg; } catch {}
      throw new Error(msg);
    }
    const data = await r.json();
    toast(`已删除 ${data.deleted} 个文件`, 'success');
    selectedFiles.clear();
    await loadFiles();
  } catch (e) {
    toast('批量删除失败: ' + e.message, 'error');
  } finally {
    restore();
  }
});

// ---------------------------------------------------------------------------
// Boot (从 app.js 末尾移过来, 确保 selectedFiles 已声明再启动首次 loadFiles)
// ---------------------------------------------------------------------------
loadFiles();
setInterval(loadFiles, 30000);