OneBot: Leantime 改造版源码（BOM/Univer 表格/AI 接管/品牌替换等）

dev/DWGViewer/.htaccess

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+# WebAssembly 必须带正确的 MIME，否则 instantiateStreaming 会失败
+AddType application/wasm .wasm
+AddType text/javascript .js .mjs
+
+# wasm/图标体积大，允许长缓存（升级时改文件名或加 ?v=）
+<FilesMatch "\.(wasm|css|png|ico)$">
+  Header set Cache-Control "public, max-age=2592000"
+</FilesMatch>
+
+# 防下载：图纸源文件一律不允许直接 GET，只能走 api/model.php（校验短时令牌 + 解密）。
+# 查看器已经会自动走令牌流程，所以封掉不影响正常使用。
+# 如果你希望图纸可以直链下载，把下面这段删掉即可。
+<FilesMatch "\.(dwg|dxf|enc|DWG|DXF)$">
+  Require all denied
+</FilesMatch>

dev/DWGViewer/api/.htaccess

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+# 禁止直接访问图纸文件（双保险：PHP 接口已校验令牌）
+<FilesMatch "\.(dwg|dxf|enc)$">
+  Require all denied
+</FilesMatch>

dev/DWGViewer/api/model.php

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+<?php
+/**
+ * DWG/DXF 查看器 - 图纸读取接口
+ * 校验令牌 → .enc 解密 / 原文件原样 → 流式返回。
+ * SECRET 必须与 token.php、upload.php 一致。
+ */
+$SECRET = 'be323d1b90bd2fda624083d4d1d716b7';
+// 与 upload.php 保持一致的私有目录配置：图纸放 Web 目录外，web 里根本没有文件可下载
+$PRIVATE_DIR = '/volume1/dwgviewer_private';
+
+function json_out($code, $obj) {
+    http_response_code($code);
+    header('Content-Type: application/json; charset=utf-8');
+    echo json_encode($obj, JSON_UNESCAPED_UNICODE);
+    exit;
+}
+
+$f = $_GET['f'] ?? '';
+$t = $_GET['t'] ?? '';
+$e = (int)($_GET['e'] ?? 0);
+if (!$f || !$t || !preg_match('/\.(dwg|dxf|enc)$/i', $f)) json_out(400, ['error' => 'bad params']);
+if (strpos($f, '..') !== false) json_out(400, ['error' => 'bad path']);
+
+$sig = substr(hash_hmac('sha256', $f . '|' . $e, $SECRET), 0, 16);
+if (!hash_equals($sig, $t) || time() > $e) json_out(403, ['error' => 'invalid or expired token']);
+
+$root = realpath(__DIR__ . '/..');
+if ($PRIVATE_DIR !== '') {
+    // 私有目录优先（嵌入链接写纯文件名即可）；目录不存在时退回站内路径，
+    // 让留在 web 目录里的样例图纸按原路径继续可用（这些文件本来就允许直链，
+    // 退回不新增暴露面）。要保护的图纸必须移出 web 目录放进私有目录。
+    $full = realpath($PRIVATE_DIR . '/' . basename($f));
+    $ok = $full && strpos($full, realpath($PRIVATE_DIR)) === 0 && is_file($full);
+    if (!$ok) {
+        $full = realpath($root . '/' . $f);
+        $ok = $full && strpos($full, $root) === 0 && is_file($full);
+    }
+} else {
+    $full = realpath($root . '/' . $f);
+    $ok = $full && strpos($full, $root) === 0 && is_file($full);
+}
+if (!$ok) json_out(404, ['error' => 'not found']);
+
+$data = file_get_contents($full);
+$origName = basename($f);
+if (preg_match('/\.enc$/i', $f)) {
+    $nonce = substr($data, 0, 16);
+    $key = hash('sha256', $SECRET . $nonce, true);
+    $body = substr($data, 16);
+    $out = '';
+    for ($i = 0; $i < strlen($body); $i++) {
+        $out .= $body[$i] ^ $key[$i % strlen($key)];
+    }
+    // 加密体头部藏着原文件名（落盘名是随机的，链接里看不出是哪张图）
+    if (strlen($out) > 2) {
+        $nl = unpack('n', substr($out, 0, 2))[1];
+        if ($nl > 0 && $nl <= 255 && strlen($out) > 2 + $nl) {
+            $origName = substr($out, 2, $nl);
+            $out = substr($out, 2 + $nl);
+        }
+    }
+    $data = $out;
+}
+header('X-Filename: ' . rawurlencode($origName));
+header('Access-Control-Expose-Headers: X-Filename');
+
+// 上传时已经 gzip 过，解密后就是 gzip 流，直接标 Content-Encoding 让浏览器解；
+// 明文文件（如 dxf）在线压一次，DXF 文本能压到 1/8 左右
+$send = $data;
+if (substr($send, 0, 2) === "\x1f\x8b") {
+    header('Content-Encoding: gzip');
+} elseif (!ini_get('zlib.output_compression') && strlen($data) > 1024) {
+    $gz = gzencode($data, 6);
+    if ($gz !== false) { $send = $gz; header('Content-Encoding: gzip'); }
+}
+header('Content-Type: application/octet-stream');
+header('Content-Length: ' . strlen($send));
+header('Cache-Control: no-store');
+header('Content-Disposition: inline');
+echo $send;

dev/DWGViewer/api/token.php

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+<?php
+/**
+ * DWG/DXF 查看器 - 令牌接口
+ * 同源校验 + HMAC 短时令牌（5 分钟）。与 STEPViewer 的 api/token.php 同一套设计。
+ * 部署前务必改掉 SECRET。
+ */
+header('Content-Type: application/json; charset=utf-8');
+header('Cache-Control: no-store');
+
+$SECRET = 'be323d1b90bd2fda624083d4d1d716b7';
+$TTL = 300;
+
+function json_out($code, $obj) {
+    http_response_code($code);
+    echo json_encode($obj, JSON_UNESCAPED_UNICODE);
+    exit;
+}
+
+$f = $_GET['f'] ?? '';
+if (!$f || !preg_match('/\.(dwg|dxf|enc)$/i', $f)) json_out(400, ['error' => 'bad file']);
+if (strpos($f, '..') !== false) json_out(400, ['error' => 'bad path']);
+
+// 只允许本站页面来取令牌，挡掉直接爬取。
+// 优先看 Sec-Fetch-Site：由查看器页面发起的同源 fetch 恒为 same-origin（跨站 iframe
+// 嵌入也不受影响，且不会被父站点的 Referrer-Policy 剥掉）；没有该头的旧浏览器
+// 退回「Referer 含本站 host」的校验。直链/curl 两种都过不了。
+$fetchSite = $_SERVER['HTTP_SEC_FETCH_SITE'] ?? '';
+$referer = $_SERVER['HTTP_REFERER'] ?? '';
+$host = $_SERVER['HTTP_HOST'] ?? '';
+if ($fetchSite !== '') {
+    if ($fetchSite !== 'same-origin' && $fetchSite !== 'same-site') json_out(403, ['error' => 'forbidden']);
+} elseif (!$host || strpos($referer, $host) === false) {
+    json_out(403, ['error' => 'forbidden']);
+}
+
+$exp = time() + $TTL;
+$sig = substr(hash_hmac('sha256', $f . '|' . $exp, $SECRET), 0, 16);
+json_out(200, ['token' => $sig, 'expires' => $exp]);

dev/DWGViewer/api/upload.php

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+<?php
+/**
+ * DWG/DXF 查看器 - 上传接口
+ * 接收原始字节流 + X-Filename 头，gzip 后异或加密存成 uploads/xxx.enc。
+ * 落盘就是密文，即使目录被翻到也拿不到可用的图纸。
+ * SECRET 必须与 token.php、model.php 一致。
+ */
+header('Content-Type: application/json; charset=utf-8');
+
+$SECRET = 'be323d1b90bd2fda624083d4d1d716b7';
+$MAX_SIZE = 200 * 1024 * 1024;
+// 私有目录：Web 目录外的绝对路径，图纸只存这里，web 目录里根本没有图纸文件可下载。
+// 群晖 File Station 在 web 目录外建 /volume1/dwgviewer_private 并给 http 用户组读写权限；
+// 路径不同就改成你的实际路径。
+$PRIVATE_DIR = '/volume1/dwgviewer_private';
+
+function json_out($code, $obj) {
+    http_response_code($code);
+    echo json_encode($obj, JSON_UNESCAPED_UNICODE);
+    exit;
+}
+
+if ($_SERVER['REQUEST_METHOD'] !== 'POST') json_out(405, ['error' => 'method not allowed']);
+
+// 只允许本站页面发起上传（与 token.php 同一策略：Sec-Fetch-Site 优先、Referer 兜底，
+// 父站点的 Referrer-Policy 剥不掉 Sec-Fetch-Site，跨站 iframe 嵌入也能上传）
+$fetchSite = $_SERVER['HTTP_SEC_FETCH_SITE'] ?? '';
+$referer = $_SERVER['HTTP_REFERER'] ?? '';
+$host = $_SERVER['HTTP_HOST'] ?? '';
+if ($fetchSite !== '') {
+    if ($fetchSite !== 'same-origin' && $fetchSite !== 'same-site') json_out(403, ['error' => 'forbidden']);
+} elseif (!$host || strpos($referer, $host) === false) {
+    json_out(403, ['error' => 'forbidden']);
+}
+
+$len = (int)($_SERVER['CONTENT_LENGTH'] ?? 0);
+if ($len <= 0) json_out(400, ['error' => 'empty body']);
+if ($len > $MAX_SIZE) json_out(413, ['error' => 'file too large (max 200MB)']);
+
+$raw = urldecode($_SERVER['HTTP_X_FILENAME'] ?? 'drawing.dwg');
+$base = basename($raw);
+$safe = preg_replace('/[^\w.\-\x{4e00}-\x{9fff}]/u', '_', $base);
+if (!$safe || !preg_match('/\.(dwg|dxf)$/i', $safe)) json_out(400, ['error' => '只支持 .dwg / .dxf']);
+if (strlen($safe) > 200) $safe = substr($safe, 0, 200);
+
+// 落盘名是纯随机的，不带原文件名也不带真实后缀：
+// 嵌入链接里就看不出这是哪张图、属于哪个项目，也没法按名字猜其它图纸。
+// 原文件名放进加密体里，读取时由 model.php 通过 X-Filename 头带回来显示。
+$name = bin2hex(random_bytes(12)) . '.enc';
+
+$data = file_get_contents('php://input');
+if ($data === false || strlen($data) !== $len) json_out(400, ['error' => 'incomplete upload']);
+
+// 存储层压缩：DWG 本身已压过，DXF 文本能压到 1/8
+$rawSize = strlen($data);
+$data = gzencode($data, 6);
+if ($data === false) json_out(500, ['error' => 'gzip failed']);
+// 加密体 = 2 字节名字长度 + 原文件名 + gzip 数据
+$data = pack('n', strlen($safe)) . $safe . $data;
+
+$dir = $PRIVATE_DIR !== '' ? $PRIVATE_DIR : (__DIR__ . '/../uploads');
+if (!is_dir($dir)) @mkdir($dir, 0755, true);
+if (!is_dir($dir)) json_out(500, ['error' => 'upload dir not writable']);
+
+$nonce = random_bytes(16);
+$key = hash('sha256', $SECRET . $nonce, true);
+$enc = '';
+for ($i = 0; $i < strlen($data); $i++) {
+    $enc .= $data[$i] ^ $key[$i % strlen($key)];
+}
+
+if (file_put_contents($dir . '/' . $name, $nonce . $enc) === false) {
+    json_out(500, ['error' => 'write failed']);
+}
+// 私有目录模式下返回裸文件名：嵌入链接就是 ?file=xxx.enc，读取端按 basename 在私有目录找
+$entryPath = ($PRIVATE_DIR !== '' ? '' : 'uploads/') . $name;
+
+// 记入首页数模库（入口目录的 library.json，2D/3D 共享）；库写失败不影响上传本身
+try {
+    add_to_library($entryPath, $safe, '2d');
+} catch (Throwable $e) { /* 忽略 */ }
+
+json_out(200, ['path' => $entryPath, 'name' => $safe, 'size' => $rawSize]);
+
+/**
+ * 把刚上传的文件追加进首页数模库（../../library.json）：
+ * 同路径已有记录就刷新名称和时间，否则插到最前。
+ */
+function add_to_library($path, $name, $type) {
+    $libFile = dirname(__DIR__, 2) . '/library.json';
+    $records = [];
+    if (is_file($libFile)) {
+        $old = json_decode((string)file_get_contents($libFile), true);
+        if (is_array($old) && isset($old['records']) && is_array($old['records'])) $records = $old['records'];
+    }
+    $found = false;
+    foreach ($records as $i => $rec) {
+        if (isset($rec['path']) && $rec['path'] === $path) {
+            $records[$i]['name'] = $name;
+            $records[$i]['time'] = time();
+            $found = true;
+            break;
+        }
+    }
+    if (!$found) {
+        array_unshift($records, ['path' => $path, 'name' => $name, 'type' => $type, 'note' => '', 'time' => time()]);
+    }
+    @file_put_contents($libFile, json_encode(['records' => $records], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES), LOCK_EX);
+}

dev/DWGViewer/app.js

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+/**
+ * DWG / DXF 图纸查看器 —— 界面与交互装配。
+ *
+ * 数据流：文件 → source.js(解析) → flatten.js(展平成显示列表) → render.js(画)
+ * 这里只负责把 UI 事件接到上面三层，以及图层面板、测量/批注工具、导出等外围功能。
+ */
+
+import ACI from './libs/dxf-parser/AutoCadColorIndex.js'
+import { flatten } from './js/flatten.js'
+import { BACKGROUNDS, Renderer } from './js/render.js'
+import { extOf, loadDrawing } from './js/source.js'
+import { ANNO_MODES, AnnoTool, MEASURE_MODES, MeasureTool, Snapper } from './js/tools.js'
+
+const $ = (id) => document.getElementById(id)
+const params = new URLSearchParams(location.search)
+
+// ---------------------------------------------------------------- 状态
+
+const S = {
+  doc: null,
+  shapes: [],
+  layerStats: new Map(),     // 图层名 → 图元数
+  tool: 'select',            // select | measure | anno | zoomBox
+  embed: params.get('embed') === '1',
+}
+
+const wrap = $('canvasWrap')
+const renderer = new Renderer(wrap)
+const snapper = new Snapper(renderer)
+const measure = new MeasureTool(renderer, snapper, () => { renderStats(); renderer.requestDraw() })
+const anno = new AnnoTool(renderer, () => renderer.requestDraw())
+
+renderer.overlay = (ctx, r) => {
+  anno.draw(ctx, r)
+  if (S.tool === 'measure' || measure.results.length) measure.draw(ctx, r)
+  drawRubber(ctx, r)
+}
+
+if (S.embed) document.body.classList.add('embed')
+
+// ---------------------------------------------------------------- 加载
+
+function setLoading(on, text) {
+  $('loading').classList.toggle('hidden', !on)
+  if (text) $('loadingText').textContent = text
+}
+
+function showError(msg) {
+  let box = $('errBox')
+  if (!box) {
+    box = document.createElement('div')
+    box.id = 'errBox'
+    $('viewport').appendChild(box)
+  }
+  box.innerHTML = ''
+  box.append(msg)
+  const b = document.createElement('button')
+  b.className = 'small-btn'
+  b.textContent = '关闭'
+  b.style.marginLeft = '12px'
+  b.onclick = () => box.remove()
+  box.appendChild(b)
+}
+
+async function openBuffer(name, buffer) {
+  setLoading(true, '正在解析图纸...')
+  const t0 = performance.now()
+  try {
+    const doc = await loadDrawing(name, buffer, (m) => setLoading(true, m))
+    setLoading(true, '正在生成图形...')
+    await nextFrame()
+    const { shapes, bbox, stats } = flatten(doc)
+    if (!shapes.length) throw new Error('图纸里没有可显示的图元（可能是空图或全部实体类型暂不支持）')
+
+    S.doc = doc
+    S.buffer = buffer          // 留着给「上传并生成嵌入链接」用
+    applyShapes(doc, shapes, bbox)
+    measure.clear()
+    anno.clear()
+    setUnit(unitLabel(doc), true)
+    buildLayoutSelect(doc)
+
+    $('fileName').textContent = `${name}　·　${doc.format}　·　${stats.entities} 实体 / ${shapes.length} 图元`
+    renderInfo(stats, performance.now() - t0)
+    setStatus(`已加载 ${name}`)
+    $('modelInfo').textContent = `${shapes.length} 图元 · ${(performance.now() - t0).toFixed(0)}ms`
+  } catch (e) {
+    console.error(e)
+    showError(`打开失败：${e && e.message ? e.message : e}`)
+  } finally {
+    setLoading(false)
+  }
+}
+
+const nextFrame = () => new Promise((r) => requestAnimationFrame(() => r()))
+
+/** 把一份显示列表装进渲染器并刷新左侧图层面板 */
+function applyShapes(doc, shapes, bbox) {
+  S.shapes = shapes
+  S.layerStats = new Map()
+  for (const s of shapes) S.layerStats.set(s.layer, (S.layerStats.get(s.layer) || 0) + 1)
+  renderer.setDocument(doc, shapes, bbox)
+  renderer.zoomExtents()
+  isolated = null
+  buildLayerPanel()
+  renderer.draw()
+}
+
+/**
+ * 模型空间 / 图纸空间布局切换。
+ * 国内机械图多半把图框画在模型空间，所以只有布局里真有实体时才显示这个下拉。
+ */
+function buildLayoutSelect(doc) {
+  const sel = $('layoutSelect')
+  const used = (doc.layouts || []).filter((l) => l.entities && l.entities.length)
+  sel.innerHTML = ''
+  const add = (val, text) => { const o = document.createElement('option'); o.value = val; o.textContent = text; sel.appendChild(o) }
+  add('model', '模型空间')
+  used.forEach((l, i) => add(String(i), l.name.replace(/^\*/, '') || `布局 ${i + 1}`))
+  $('layoutBox').classList.toggle('hidden', used.length === 0)
+  sel.value = 'model'
+  sel.onchange = () => {
+    const ents = sel.value === 'model' ? doc.modelEntities : used[+sel.value].entities
+    const { shapes, bbox } = flatten(doc, { entities: ents })
+    if (!shapes.length) { showError('该布局里没有可显示的图元'); sel.value = 'model'; return }
+    applyShapes(doc, shapes, bbox)
+    $('modelInfo').textContent = `${shapes.length} 图元`
+  }
+}
+
+/** 单位：DWG 的 $INSUNITS 常年是默认值，所以给用户留了手动覆盖 */
+function setUnit(u, fromFile) {
+  measure.unit = u
+  $('optUnit').value = u
+  $('optUnitSrc').textContent = fromFile ? '自动' : '手动'
+  measure.refresh()
+  renderStats()
+  renderer.requestDraw()
+}
+
+function openFile(file) {
+  const ext = extOf(file.name)
+  if (ext !== 'dwg' && ext !== 'dxf') { showError('只支持 .dwg 和 .dxf 文件'); return }
+  S.loadPath = null               // 本地文件没有服务器路径，嵌入前要先上传
+  const fr = new FileReader()
+  fr.onload = () => openBuffer(file.name, fr.result)
+  fr.onerror = () => showError('文件读取失败')
+  setLoading(true, '正在读取文件...')
+  fr.readAsArrayBuffer(file)
+}
+
+async function openUrl(url, loadPath) {
+  setLoading(true, '正在读取图纸...')
+  try {
+    const { buffer, name } = await fetchDrawing(url)
+    S.loadPath = loadPath || url      // 嵌入链接沿用真正打开的路径，别用裸文件名
+    await openBuffer(name || url.split('/').pop() || url, buffer)
+  } catch (e) {
+    setLoading(false)
+    showError(`读取失败：${e.message}（${url}）`)
+  }
+}
+
+/**
+ * 取图纸字节。
+ *
+ * 站内路径优先走「令牌 → 解密接口」：服务端用 .htaccess 封掉了 .dwg/.dxf/.enc 的直接 GET，
+ * 只有拿到 5 分钟有效的 HMAC 令牌才能通过 api/model.php 读到内容，挡住直链下载和爬取。
+ * 接口不存在时（比如本地 python 开发服务器没有 PHP）自动退回直连，不影响开发。
+ */
+async function fetchDrawing(url) {
+  if (!/^https?:\/\//i.test(url)) {
+    const via = await tryTokenFetch(url)
+    if (via) return via
+  }
+  const res = await fetch(url)
+  if (!res.ok) throw new Error(`HTTP ${res.status}`)
+  return { buffer: await res.arrayBuffer(), name: '' }
+}
+
+/**
+ * 走令牌接口取图纸；接口没部署就返回 null 让调用方直连。
+ *
+ * 判断「接口有没有部署」看的是响应内容而不是异常文本：本地开发用的 python
+ * 静态服务器不会执行 PHP，会把 token.php 的源码当普通文件 200 发回来，
+ * 只看状态码会误判成接口可用，然后 json() 直接炸掉。
+ */
+async function tryTokenFetch(url) {
+  let tok
+  try {
+    const tr = await fetch(`api/token.php?f=${encodeURIComponent(url)}`, { cache: 'no-store' })
+    if (!tr.ok) return null
+    if (!/application\/json/i.test(tr.headers.get('content-type') || '')) return null
+    tok = await tr.json()
+  } catch {
+    return null                       // 网络层失败：当作没部署
+  }
+  if (!tok || !tok.token) return null
+  // 到这里说明接口确实在跑，它再拒绝就该明确报错，不能悄悄退回直连
+  const mr = await fetch(
+    `api/model.php?f=${encodeURIComponent(url)}&t=${tok.token}&e=${tok.expires}`, { cache: 'no-store' })
+  if (!mr.ok) {
+    const j = await mr.json().catch(() => ({}))
+    throw new Error(j.error || `读取接口返回 ${mr.status}`)
+  }
+  // 落盘名是随机的，真实文件名由接口通过头带回
+  const hdr = mr.headers.get('X-Filename')
+  return { buffer: await mr.arrayBuffer(), name: hdr ? decodeURIComponent(hdr) : '' }
+}
+
+/** 把当前图纸上传到服务器（加密落盘 + 随机文件名），返回可用于嵌入的路径 */
+async function uploadCurrent() {
+  if (!S.buffer) throw new Error('还没有打开图纸')
+  const res = await fetch('api/upload.php', {
+    method: 'POST',
+    headers: { 'X-Filename': encodeURIComponent(S.doc.name), 'Content-Type': 'application/octet-stream' },
+    body: S.buffer,
+  })
+  const j = await res.json().catch(() => ({}))
+  if (!res.ok) throw new Error(j.error || `HTTP ${res.status}`)
+  return j.path
+}
+
+/**
+ * $INSUNITS → 单位标签。
+ * 只认公制的显式取值：0（未设）和 1（英寸）多半是 CAD 的默认值没改过，
+ * 国内机械图实际都是毫米，直接按英寸显示会差 25.4 倍。用户可在设置里改。
+ */
+function unitLabel(doc) {
+  const u = doc.header && doc.header.INSUNITS
+  return ({ 2: 'ft', 4: 'mm', 5: 'cm', 6: 'm', 13: 'µm' })[u] || 'mm'
+}
+
+// ---------------------------------------------------------------- 图层面板
+
+function buildLayerPanel() {
+  const box = $('tree')
+  box.innerHTML = ''
+  if (!S.doc) return
+  const names = [...S.doc.layers.keys()].sort((a, b) => a.localeCompare(b, 'zh'))
+  // 没有任何图元的图层排到后面
+  names.sort((a, b) => (S.layerStats.get(b) || 0) - (S.layerStats.get(a) || 0))
+  $('layerCount').textContent = `(${names.length})`
+
+  for (const name of names) {
+    const layer = S.doc.layers.get(name)
+    const n = S.layerStats.get(name) || 0
+    const row = document.createElement('div')
+    row.className = 'tree-row'
+    row.dataset.layer = name
+
+    const cb = document.createElement('input')
+    cb.type = 'checkbox'
+    cb.className = 'tree-check'
+    cb.checked = !renderer.hidden.has(name)
+    cb.onchange = () => {
+      if (cb.checked) renderer.hidden.delete(name); else renderer.hidden.add(name)
+      row.classList.toggle('off', !cb.checked)
+      renderer.requestDraw()
+    }
+
+    const sw = document.createElement('span')
+    sw.className = 'layer-swatch'
+    sw.style.background = swatchColor(layer)
+
+    const lb = document.createElement('span')
+    lb.className = 'tree-label'
+    lb.textContent = name
+    lb.title = `${name}（${n} 个图元）`
+
+    const num = document.createElement('span')
+    num.className = 'tree-num'
+    num.textContent = n || ''
+
+    row.append(cb, sw, lb, num)
+    // 点行（不含勾选框）= 只显示这一层
+    row.onclick = (e) => {
+      if (e.target === cb) return
+      isolateLayer(name)
+    }
+    box.appendChild(row)
+  }
+  if (!names.length) box.innerHTML = '<div class="tree-empty">没有图层</div>'
+}
+
+function swatchColor(layer) {
+  if (!layer) return '#000'
+  let c = 0
+  if (typeof layer.trueColor === 'number') c = layer.trueColor
+  else if (layer.colorIndex != null) {
+    const idx = Math.abs(layer.colorIndex)
+    c = idx === 7 ? 0x000000 : ACI_CACHE[idx] || 0x000000
+  }
+  return `#${(c >>> 0).toString(16).padStart(6, '0')}`
+}
+
+const ACI_CACHE = ACI
+
+let isolated = null
+function isolateLayer(name) {
+  if (isolated === name) {
+    renderer.hidden.clear()
+    isolated = null
+  } else {
+    renderer.hidden.clear()
+    for (const k of S.doc.layers.keys()) if (k !== name) renderer.hidden.add(k)
+    isolated = name
+  }
+  syncLayerChecks()
+  renderer.requestDraw()
+  setStatus(isolated ? `只显示图层「${name}」，再点一次恢复` : '已显示全部图层')
+}
+
+function syncLayerChecks() {
+  for (const row of $('tree').children) {
+    const cb = row.querySelector('input')
+    if (!cb) continue
+    cb.checked = !renderer.hidden.has(row.dataset.layer)
+    row.classList.toggle('off', !cb.checked)
+  }
+}
+
+$('treeSearch').addEventListener('input', () => {
+  const q = $('treeSearch').value.trim().toLowerCase()
+  for (const row of $('tree').children) {
+    const name = (row.dataset.layer || '').toLowerCase()
+    const hit = !q || name.includes(q)
+    row.style.display = hit ? '' : 'none'
+    row.classList.toggle('matched', !!q && hit)
+  }
+})
+$('btnLayerAll').onclick = () => { renderer.hidden.clear(); isolated = null; syncLayerChecks(); renderer.requestDraw() }
+$('btnLayerNone').onclick = () => {
+  for (const k of S.doc ? S.doc.layers.keys() : []) renderer.hidden.add(k)
+  isolated = null; syncLayerChecks(); renderer.requestDraw()
+}
+$('btnLayerInvert').onclick = () => {
+  for (const k of S.doc ? S.doc.layers.keys() : []) {
+    if (renderer.hidden.has(k)) renderer.hidden.delete(k); else renderer.hidden.add(k)
+  }
+  isolated = null; syncLayerChecks(); renderer.requestDraw()
+}
+
+// ---------------------------------------------------------------- 工具栏
+
+function setTool(t) {
+  S.tool = t
+  for (const b of document.querySelectorAll('#toolbar .tool-btn[data-tool]')) {
+    b.classList.toggle('active', b.dataset.tool === t)
+  }
+  const isMeasure = t === 'measure'
+  const isAnno = t === 'anno'
+  $('toolbar').classList.toggle('hidden', isMeasure || isAnno)
+  $('measurePanel').classList.toggle('hidden', !isMeasure)
+  $('annoPanel').classList.toggle('hidden', !isAnno)
+  if (!isMeasure) measure.setMode(null)
+  if (!isAnno) anno.setMode(null)
+  wrap.classList.toggle('crosshair', isMeasure || isAnno || t === 'zoomBox')
+  setStatus(TOOL_HINT[t] || '')
+  renderer.requestDraw()
+}
+
+const TOOL_HINT = {
+  select: '选择：点击图元查看属性 · 拖动平移 · 滚轮缩放 · 双击全图',
+  measure: '测量：先选测量方式，再在图上点取（自动捕捉端点/中点/圆心）',
+  anno: '批注：先选批注方式，在图上拖动绘制',
+  zoomBox: '框选放大：按住左键拖出矩形',
+}
+
+for (const b of document.querySelectorAll('#toolbar .tool-btn[data-tool]')) {
+  b.onclick = () => setTool(b.dataset.tool)
+}
+
+// 测量子面板
+const mBox = $('measureModes')
+for (const m of MEASURE_MODES) {
+  const b = document.createElement('button')
+  b.className = 'measure-btn'
+  b.title = m.name
+  b.innerHTML = `<img src="./icons/${m.icon}" alt=""><span>${m.name}</span>`
+  b.onclick = () => {
+    const on = measure.mode === m.id
+    measure.setMode(on ? null : m.id)
+    for (const x of mBox.children) x.classList.remove('active')
+    if (!on) b.classList.add('active')
+    setStatus(on ? '' : `${m.name}：在图上点取`)
+  }
+  mBox.appendChild(b)
+}
+$('btnMeasureClose').onclick = () => setTool('select')
+$('btnMeasureClear').onclick = () => measure.clear()
+$('btnStats').onclick = () => togglePanel('stats')
+
+// 批注子面板
+const aBox = $('annoModes')
+for (const m of ANNO_MODES) {
+  const b = document.createElement('button')
+  b.className = 'measure-btn'
+  b.title = m.name
+  b.innerHTML = `<img src="./icons/${m.icon}" alt=""><span>${m.name}</span>`
+  b.onclick = () => {
+    const on = anno.mode === m.id
+    anno.setMode(on ? null : m.id)
+    for (const x of aBox.children) x.classList.remove('active')
+    if (!on) b.classList.add('active')
+  }
+  aBox.appendChild(b)
+}
+$('btnAnnoClose').onclick = () => setTool('select')
+$('btnAnnoClear').onclick = () => anno.clear()
+$('btnAnnoUndo').onclick = () => anno.undo()
+$('annoColor').oninput = (e) => { anno.color = e.target.value }
+$('annoWidth').onchange = (e) => { anno.width = +e.target.value }
+
+// 其它工具按钮
+$('btnLayerPanel').onclick = (e) => {
+  if (e) e.stopPropagation()   // 别让「点击外部收起抽屉」把这次打开又关掉
+  if (window.innerWidth <= 768) {
+    // 手机：图层面板是抽屉，点按钮开合（默认隐藏）
+    document.body.classList.toggle('tree-open')
+  } else {
+    // 桌面：默认显示，点击隐藏/显示侧栏
+    document.body.classList.toggle('no-tree')
+  }
+  renderer.resize()
+}
+// 手机抽屉：✕ 按钮关闭 + 点击抽屉外部自动收起
+const btnTreeClose = $('btnTreeClose')
+if (btnTreeClose) btnTreeClose.onclick = () => document.body.classList.remove('tree-open')
+document.addEventListener('click', (e) => {
+  if (window.innerWidth > 768 || !document.body.classList.contains('tree-open')) return
+  if (!$('treePanel').contains(e.target)) document.body.classList.remove('tree-open')
+})
+$('btnFind').onclick = () => togglePanel('find')
+$('btnSettings').onclick = () => togglePanel('settings')
+$('btnInfo').onclick = () => togglePanel('info')
+$('btnReset').onclick = () => { setRotation(0); renderer.zoomExtents(); renderer.requestDraw() }
+$('btnLineWeight').onclick = () => {
+  renderer.opts.lineWeight = !renderer.opts.lineWeight
+  $('btnLineWeight').classList.toggle('active', renderer.opts.lineWeight)
+  $('optLineWeight').checked = renderer.opts.lineWeight
+  renderer.requestDraw()
+}
+$('btnSnapshot').onclick = snapshot
+$('btnPrint').onclick = printDrawing
+$('btnOpen').onclick = () => $('fileInput').click()
+$('fileInput').onchange = (e) => { if (e.target.files[0]) openFile(e.target.files[0]) }
+$('btnFullscreen').onclick = () => toggleFullscreen()
+$('btnEmbed').onclick = () => { togglePanel('embed'); updateEmbed() }
+
+for (const el of document.querySelectorAll('.panel-close')) {
+  el.onclick = () => $(`${el.dataset.panel}Panel`).classList.add('hidden')
+}
+
+function togglePanel(name) {
+  const p = $(`${name}Panel`)
+  const willShow = p.classList.contains('hidden')
+  for (const n of ['stats', 'find', 'settings', 'info', 'embed']) {
+    if (n !== name) $(`${n}Panel`).classList.add('hidden')
+  }
+  p.classList.toggle('hidden', !willShow)
+  if (willShow && name === 'find') $('findInput').focus()
+}
+
+// ---------------------------------------------------------------- 显示设置
+
+// ---- 背景（浅灰 / 米白 / 黑，与新迪 2D 一致）----
+const bgBox = $('bgSwatches')
+for (const b of BACKGROUNDS) {
+  const el = document.createElement('button')
+  el.className = 'bg-swatch'
+  el.dataset.bg = b.id
+  el.title = b.name
+  el.style.background = b.color
+  el.onclick = () => setBackground(b.id)
+  bgBox.appendChild(el)
+}
+
+/** 背景偏好存本地，下次打开还是上次那个底 */
+function setBackground(id) {
+  const b = BACKGROUNDS.find((x) => x.id === id) || BACKGROUNDS[0]
+  renderer.opts.bg = b.color
+  for (const el of bgBox.children) el.classList.toggle('active', el.dataset.bg === b.id)
+  $('btnBg').classList.toggle('active', renderer.isDarkBg)
+  try { localStorage.setItem('dwgviewer.bg', b.id) } catch { /* 隐私模式下写不了，忽略 */ }
+  renderer.requestDraw()
+}
+
+/** 工具栏那个按钮循环切三种底 */
+$('btnBg').onclick = () => {
+  const i = BACKGROUNDS.findIndex((b) => b.color === renderer.opts.bg)
+  const next = BACKGROUNDS[(i + 1) % BACKGROUNDS.length]
+  setBackground(next.id)
+  setStatus(`背景：${next.name}`)
+}
+$('optContrast').onchange = (e) => { renderer.opts.autoContrast = e.target.checked; renderer.requestDraw() }
+
+// ---- 视图旋转 ----
+function setRotation(rad, fromSlider) {
+  renderer.setRotation(rad)
+  const deg = Math.round((renderer.view.rot * 180) / Math.PI)
+  if (!fromSlider) $('optRot').value = deg
+  $('optRotVal').textContent = `${deg}°`
+  renderer.requestDraw()
+}
+/** 转 90°：原本铺满视口的话转完继续铺满，已经放大过就保持倍数不动 */
+function rotate90(dir) {
+  const wasFitted = renderer.isFitted()
+  setRotation(renderer.view.rot + dir * Math.PI / 2)
+  if (wasFitted) renderer.zoomExtents()
+  renderer.requestDraw()
+}
+$('btnRotL2').onclick = () => rotate90(1)
+$('btnRotR2').onclick = () => rotate90(-1)
+$('btnRot0').onclick = () => setRotation(0)
+$('optRot').oninput = (e) => setRotation((+e.target.value * Math.PI) / 180, true)
+
+// ---- 全屏（底部工具栏那个在嵌入模式下也能点到）----
+function toggleFullscreen() {
+  if (document.fullscreenElement) document.exitFullscreen()
+  else document.documentElement.requestFullscreen()
+}
+$('btnFull').onclick = toggleFullscreen
+$('optText').onchange = (e) => { renderer.opts.showText = e.target.checked; renderer.requestDraw() }
+$('optHatch').onchange = (e) => { renderer.opts.showHatch = e.target.checked; renderer.requestDraw() }
+$('optLineWeight').onchange = (e) => {
+  renderer.opts.lineWeight = e.target.checked
+  $('btnLineWeight').classList.toggle('active', e.target.checked)
+  renderer.requestDraw()
+}
+$('optLwScale').oninput = (e) => {
+  renderer.opts.lineWeightScale = e.target.value / 100
+  $('optLwVal').textContent = `${(e.target.value / 100).toFixed(1)}x`
+  if (renderer.opts.lineWeight) renderer.requestDraw()
+}
+$('optUnit').onchange = (e) => setUnit(e.target.value, false)
+$('optPrec').oninput = (e) => {
+  measure.precision = +e.target.value
+  $('optPrecVal').textContent = e.target.value
+  measure.refresh()
+  renderStats()
+  renderer.requestDraw()
+}
+
+// ---------------------------------------------------------------- 鼠标交互
+
+let drag = null
+let rubber = null           // 框选/框放大的临时矩形（屏幕 CSS 像素）
+
+wrap.addEventListener('contextmenu', (e) => e.preventDefault())
+
+wrap.addEventListener('pointerdown', (e) => {
+  wrap.setPointerCapture(e.pointerId)
+  const pos = local(e)
+  // 中键/右键始终是平移；左键看当前工具
+  if (e.button === 1 || e.button === 2) {
+    drag = { mode: 'pan', x: e.clientX, y: e.clientY }
+    wrap.classList.add('panning')
+    return
+  }
+  if (e.button !== 0) return
+
+  if (S.tool === 'zoomBox') { rubber = { x0: pos.x, y0: pos.y, x1: pos.x, y1: pos.y, kind: 'zoom' }; return }
+  if (S.tool === 'anno' && anno.mode) { if (anno.down(pos.x, pos.y)) { drag = { mode: 'anno' }; return } }
+  if (S.tool === 'measure' && measure.mode) return   // 测量在 pointerup 里按点击处理
+
+  drag = { mode: 'maybe-pan', x: e.clientX, y: e.clientY, sx: pos.x, sy: pos.y, moved: false }
+})
+
+wrap.addEventListener('pointermove', (e) => {
+  const pos = local(e)
+  updateCoord(pos)
+
+  if (rubber) { rubber.x1 = pos.x; rubber.y1 = pos.y; renderer.requestDraw(); return }
+  if (drag && drag.mode === 'anno') { anno.move(pos.x, pos.y); renderer.requestDraw(); return }
+  if (drag && (drag.mode === 'pan' || drag.mode === 'maybe-pan')) {
+    const dx = e.clientX - drag.x, dy = e.clientY - drag.y
+    if (drag.mode === 'maybe-pan' && Math.hypot(dx, dy) < 3) return
+    if (drag.mode === 'maybe-pan') { drag.mode = 'pan'; drag.moved = true; wrap.classList.add('panning') }
+    renderer.panByPixels(dx, dy)
+    drag.x = e.clientX; drag.y = e.clientY
+    renderer.requestDraw()
+    return
+  }
+
+  if (S.tool === 'measure' && measure.mode) { measure.hover(pos.x, pos.y); renderer.requestDraw(); return }
+  if (S.tool === 'select') {
+    const idx = renderer.pick(pos.x, pos.y, 6)
+    if (idx !== renderer.highlight) { renderer.highlight = idx; renderer.requestDraw() }
+  }
+})
+
+wrap.addEventListener('pointerup', (e) => {
+  const pos = local(e)
+  wrap.classList.remove('panning')
+  try { wrap.releasePointerCapture(e.pointerId) } catch { /* 指针已释放 */ }
+
+  if (rubber) {
+    const r = rubber; rubber = null
+    if (Math.abs(r.x1 - r.x0) > 6 && Math.abs(r.y1 - r.y0) > 6) {
+      const a = renderer.toWorld(r.x0, r.y0), b = renderer.toWorld(r.x1, r.y1)
+      renderer.zoomToBox([Math.min(a.x, b.x), Math.min(a.y, b.y), Math.max(a.x, b.x), Math.max(a.y, b.y)])
+      setTool('select')
+    }
+    renderer.requestDraw()
+    return
+  }
+  if (drag && drag.mode === 'anno') { anno.up(); drag = null; return }
+  const wasPan = drag && drag.mode === 'pan'
+  const wasClick = drag && drag.mode === 'maybe-pan'
+  drag = null
+  if (wasPan) return
+
+  if (e.button !== 0) return
+  if (S.tool === 'measure' && measure.mode) { measure.click(pos.x, pos.y); renderer.requestDraw(); return }
+  if (S.tool === 'select' && wasClick) selectAt(pos)
+})
+
+wrap.addEventListener('dblclick', () => {
+  if (S.tool === 'measure' && measure.mode) { measure.finish(); return }
+  renderer.zoomExtents()
+  renderer.requestDraw()
+})
+
+wrap.addEventListener('wheel', (e) => {
+  e.preventDefault()
+  const pos = local(e)
+  const f = e.deltaY < 0 ? 1.18 : 1 / 1.18
+  renderer.zoomAt(pos.x, pos.y, f)
+  renderer.requestDraw()
+  updateCoord(pos)
+}, { passive: false })
+
+function local(e) {
+  const r = wrap.getBoundingClientRect()
+  return { x: e.clientX - r.left, y: e.clientY - r.top }
+}
+
+function updateCoord(pos) {
+  const w = renderer.toWorld(pos.x, pos.y)
+  $('coordText').textContent = S.doc ? `X ${w.x.toFixed(2)}   Y ${w.y.toFixed(2)}   1:${(1 / renderer.view.scale * renderer.dpr).toFixed(2)}` : ''
+}
+
+function selectAt(pos) {
+  const idx = renderer.pick(pos.x, pos.y, 6)
+  renderer.selection.clear()
+  if (idx != null) {
+    renderer.selection.add(idx)
+    showProps(renderer.shapes[idx])
+  } else {
+    $('propPanel').classList.add('hidden')
+  }
+  renderer.requestDraw()
+}
+
+function drawRubber(ctx, r) {
+  if (!rubber) return
+  const d = r.dpr
+  ctx.save()
+  // 框选矩形是屏幕上的物件，不跟着图纸转，所以撤掉 overlay 的视图旋转
+  ctx.setTransform(1, 0, 0, 1, 0, 0)
+  ctx.strokeStyle = '#2b9ae8'
+  ctx.fillStyle = 'rgba(43,154,232,.12)'
+  ctx.lineWidth = 1.5 * d
+  ctx.setLineDash([5 * d, 4 * d])
+  const x = Math.min(rubber.x0, rubber.x1) * d, y = Math.min(rubber.y0, rubber.y1) * d
+  const w = Math.abs(rubber.x1 - rubber.x0) * d, h = Math.abs(rubber.y1 - rubber.y0) * d
+  ctx.fillRect(x, y, w, h)
+  ctx.strokeRect(x, y, w, h)
+  ctx.restore()
+}
+
+document.addEventListener('keydown', (e) => {
+  if (e.target.tagName === 'INPUT' || e.target.tagName === 'TEXTAREA') return
+  if (e.key === 'Escape') {
+    measure.cancel(); anno.setMode(anno.mode); rubber = null
+    renderer.selection.clear(); $('propPanel').classList.add('hidden')
+    renderer.requestDraw()
+  } else if (e.key === 'Enter') {
+    measure.finish(); renderer.requestDraw()
+  } else if (e.key === 'e' || e.key === 'E') {
+    renderer.zoomExtents(); renderer.requestDraw()
+  }
+})
+
+// ---------------------------------------------------------------- 面板内容
+
+function renderStats() {
+  const box = $('statsList')
+  box.innerHTML = ''
+  if (!measure.results.length) { box.innerHTML = '<div class="stats-empty">暂无测量结果</div>'; return }
+  measure.results.forEach((r, i) => {
+    const row = document.createElement('div')
+    row.className = 'stats-row'
+    row.innerHTML = `<span class="stats-type">${r.type}</span><span class="stats-value" title="${r.text}">${r.text}</span>`
+    const del = document.createElement('span')
+    del.className = 'stats-del'
+    del.textContent = '×'
+    del.onclick = () => measure.remove(i)
+    row.appendChild(del)
+    box.appendChild(row)
+  })
+}
+
+function renderInfo(stats, ms) {
+  const d = S.doc
+  const b = renderer.bbox
+  const kv = (k, v) => `<div class="kv"><b>${k}</b><span>${v}</span></div>`
+  const types = Object.entries(stats.byType).sort((a, b2) => b2[1] - a[1])
+    .map(([k, v]) => `${k} ${v}`).join('、')
+  $('infoBody').innerHTML =
+    kv('文件', d.name) +
+    kv('格式', d.format) +
+    kv('图层', d.layers.size) +
+    kv('块', d.blocks.size) +
+    kv('实体', stats.entities) +
+    kv('图元', S.shapes.length) +
+    kv('范围', `${(b[2] - b[0]).toFixed(1)} × ${(b[3] - b[1]).toFixed(1)} ${measure.unit}`) +
+    kv('解析耗时', `${ms.toFixed(0)} ms`) +
+    kv('实体分布', types || '—') +
+    `<div class="lic">解析内核：${d.format === 'DWG' ? 'LibreDWG (WebAssembly)' : 'dxf-parser'}　许可证 ${d.license}。
+     ${d.format === 'DWG' ? 'GPL-3.0 会传染到分发的前端代码，商用前请评估，或把 DWG 解析换成服务端/商业 SDK。' : ''}</div>`
+}
+
+function showProps(s) {
+  if (!s) return
+  const e = s.ent || {}
+  const kv = (k, v) => (v == null || v === '' ? '' : `<div class="kv"><b>${k}</b><span>${v}</span></div>`)
+  const b = s.bbox
+  $('propBody').innerHTML =
+    kv('类型', e.type || s.kind) +
+    kv('图层', s.layer) +
+    kv('句柄', e.handle) +
+    kv('颜色', `#${(s.color >>> 0).toString(16).padStart(6, '0')}`) +
+    kv('线型', s.lt || 'Continuous') +
+    kv('线宽', s.lw >= 0 ? `${(s.lw / 100).toFixed(2)} mm` : '随层') +
+    kv('文字', s.plain ? s.plain.slice(0, 200) : '') +
+    kv('半径', s.kind === 'arc' ? s.rx.toFixed(3) : '') +
+    kv('包围盒', `${(b[2] - b[0]).toFixed(2)} × ${(b[3] - b[1]).toFixed(2)}`)
+  $('propPanel').classList.remove('hidden')
+}
+
+// ---------------------------------------------------------------- 文字查找
+
+$('findInput').addEventListener('keydown', (e) => { if (e.key === 'Enter') doFind() })
+
+function doFind() {
+  const q = $('findInput').value.trim().toLowerCase()
+  const box = $('findResult')
+  box.innerHTML = ''
+  if (!q) { box.innerHTML = '<div class="stats-empty">输入关键字后回车</div>'; return }
+  const hits = []
+  for (const s of S.shapes) {
+    if (!s.plain) continue
+    if (s.plain.toLowerCase().includes(q)) hits.push(s)
+    if (hits.length >= 300) break
+  }
+  if (!hits.length) { box.innerHTML = '<div class="stats-empty">没有匹配的文字</div>'; return }
+  for (const s of hits) {
+    const row = document.createElement('div')
+    row.className = 'find-row'
+    row.innerHTML = `${escapeHtml(s.plain.slice(0, 60))}<span class="find-layer">${escapeHtml(s.layer)}</span>`
+    row.onclick = () => {
+      const b = s.bbox
+      const pad = Math.max((b[2] - b[0]), (b[3] - b[1])) * 6 + 1
+      renderer.zoomToBox([b[0] - pad, b[1] - pad, b[2] + pad, b[3] + pad])
+      renderer.selection.clear()
+      renderer.selection.add(s.i)
+      renderer.requestDraw()
+    }
+    box.appendChild(row)
+  }
+  setStatus(`找到 ${hits.length} 处文字`)
+}
+
+const escapeHtml = (s) => String(s).replace(/[&<>"]/g, (c) => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;' }[c]))
+
+// ---------------------------------------------------------------- 导出
+
+function snapshot() {
+  renderer.draw()
+  renderer.canvas.toBlob((blob) => {
+    const a = document.createElement('a')
+    a.href = URL.createObjectURL(blob)
+    a.download = `${(S.doc && S.doc.name || 'drawing').replace(/\.[^.]+$/, '')}.png`
+    a.click()
+    setTimeout(() => URL.revokeObjectURL(a.href), 5000)
+  }, 'image/png')
+}
+
+function printDrawing() {
+  if (!S.doc) return
+  renderer.draw()
+  const url = renderer.canvas.toDataURL('image/png')
+  const w = window.open('', '_blank')
+  if (!w) { showError('浏览器拦截了打印窗口，请允许弹出窗口'); return }
+  w.document.write(`<!DOCTYPE html><html><head><meta charset="utf-8"><title>${escapeHtml(S.doc.name)}</title>
+    <style>@page{size:auto;margin:8mm}body{margin:0}img{width:100%}</style></head>
+    <body><img src="${url}" onload="window.focus();window.print();"></body></html>`)
+  w.document.close()
+}
+
+// ---------------------------------------------------------------- 嵌入
+
+function updateEmbed() {
+  // 默认沿用图纸真正打开时的路径（相对查看器目录），避免生成打不开的裸文件名链接；
+  // 本地拖进来的图纸没有服务器路径，得先「上传当前图纸」。
+  // 用 ?file= 打开时把真实路径回填到输入框（与 STEPViewer 行为一致），
+  // 否则「图纸路径」框空着、只有地址生成，容易误以为坏了。
+  if (S.loadPath && !$('embedPath').value.trim()) $('embedPath').value = S.loadPath
+  const path = $('embedPath').value.trim()
+  const base = location.origin + location.pathname
+  if (!path) {
+    $('embedUrl').value = ''
+    $('embedCode').value = ''
+    return
+  }
+  const url = `${base}?file=${encodeURIComponent(path)}&embed=1`
+  $('embedUrl').value = url
+  $('embedCode').value = `<iframe src="${url}" width="100%" height="640" frameborder="0" allowfullscreen></iframe>`
+}
+$('embedPath').addEventListener('input', updateEmbed)
+$('btnUpload').onclick = async () => {
+  const btn = $('btnUpload')
+  btn.disabled = true
+  btn.textContent = '上传中...'
+  try {
+    const path = await uploadCurrent()
+    if (!path) throw new Error('上传接口返回异常（接口未部署）')
+    $('embedPath').value = path
+    updateEmbed()
+    setStatus(`已加密上传：${path}`)
+    // 嵌在入口页里时通知它刷新首页数模库
+    try { window.parent.postMessage({ type: 'library-updated' }, '*') } catch { /* 独立打开 */ }
+  } catch (e) {
+    showError(`上传失败：${e.message}（本地开发服务器没有 PHP，需要在正式站点上试）`)
+  } finally {
+    btn.disabled = false
+    btn.textContent = '上传当前图纸'
+  }
+}
+$('btnCopyUrl').onclick = () => copy($('embedUrl').value)
+$('btnCopyCode').onclick = () => copy($('embedCode').value)
+function copy(t) {
+  navigator.clipboard.writeText(t).then(() => setStatus('已复制到剪贴板'), () => setStatus('复制失败，请手动选择'))
+}
+
+// ---------------------------------------------------------------- 杂项
+
+function setStatus(t) { $('statusText').textContent = t || TOOL_HINT[S.tool] || '就绪' }
+
+new ResizeObserver(() => renderer.resize()).observe(wrap)
+
+// 拖拽打开
+let dragDepth = 0
+document.addEventListener('dragenter', (e) => { e.preventDefault(); dragDepth++; $('dropOverlay').classList.remove('hidden') })
+document.addEventListener('dragleave', () => { if (--dragDepth <= 0) { dragDepth = 0; $('dropOverlay').classList.add('hidden') } })
+document.addEventListener('dragover', (e) => e.preventDefault())
+document.addEventListener('drop', (e) => {
+  e.preventDefault()
+  dragDepth = 0
+  $('dropOverlay').classList.add('hidden')
+  const f = e.dataTransfer.files[0]
+  if (f) openFile(f)
+})
+
+// 调试用：控制台里可以直接摸到渲染器、文档和工具
+window.__R = renderer
+window.__S = S
+window.__ANNO = anno
+window.__MEASURE = measure
+
+// 恢复上次的背景偏好；嵌入时可用 ?bg=black|beige|grey 直接指定
+let savedBg = BACKGROUNDS[0].id
+try { savedBg = params.get('bg') || localStorage.getItem('dwgviewer.bg') || savedBg } catch { /* 隐私模式读不到 */ }
+setBackground(savedBg === 'dark' ? 'black' : savedBg)
+
+// 先画一次底色，否则 alpha:false 的画布初始是黑的
+renderer.draw()
+setStatus()
+
+// 统一入口（../index.html）在 iframe 里把用户选的图纸传进来
+window.addEventListener('message', (e) => {
+  const data = e.data
+  if (!data || data.type !== 'viewer-file' || data.kind !== 'dwg') return
+  try { if (e.origin !== location.origin) return } catch { return }
+  openBuffer(data.name || 'drawing.dwg', data.buffer)
+})
+try { window.parent.postMessage({ type: 'viewer-ready' }, '*') } catch { /* 没嵌在入口里 */ }
+
+// URL 参数直接打开
+const fileParam = params.get('file')
+if (fileParam) openUrl(fileParam, fileParam)