// ========== 诊断日志（排查流式显示问题的根本手段） ==========
// ========== JS 控制台桥：console.* 全部捕获进 window.__jslog，Python 每 500ms 抽到控制台 ==========
(function() {
    try {
        var realLog = console.log.bind(console);
        var realWarn = console.warn.bind(console);
        var realErr = console.error.bind(console);
        window.__jslog = [];
        function fmt(a) {
            if (typeof a === 'string') return a;
            if (typeof a === 'object' && a !== null) {
                try { return JSON.stringify(a); } catch (e) { return String(a); }
            }
            return String(a);
        }
        function push(level, args) {
            var str = '';
            for (var i = 0; i < args.length; i++) str += (i ? ' ' : '') + fmt(args[i]);
            window.__jslog.push('[' + level + '] ' + str);
            if (window.__jslog.length > 500) window.__jslog.splice(0, window.__jslog.length - 500);
        }
        console.log = function() { push('log', Array.prototype.slice.call(arguments)); realLog.apply(null, arguments); };
        console.warn = function() { push('warn', Array.prototype.slice.call(arguments)); realWarn.apply(null, arguments); };
        console.error = function() { push('err', Array.prototype.slice.call(arguments)); realErr.apply(null, arguments); };
        window.__jslogDrain = function() {
            if (!window.__jslog || !window.__jslog.length) return '';
            var out = window.__jslog.join('\n');
            window.__jslog = [];
            return out;
        };
    } catch (e) {}
})();
window.__APP_VER = '20260721-v7';
console.log('[JS] ===== app.js 加载 ver=20260721-v7 =====');
// 公式渲染依赖本地 KaTeX（离线）；此处确认资源加载结果，缺失时打印告警便于定位
console.log('[JS] KaTeX ' + (typeof katex !== 'undefined' ? katex.version + ' 就绪' : '缺失（公式将退化为纯文本）'));
// 渲染器主线程心跳：dt 异常大 = 渲染器被阻塞（截图/重绘/GPU 等）
(function() {
    var _hbLast = Date.now();
    setInterval(function() {
        var _now = Date.now();
        var _dt = _now - _hbLast;
        _hbLast = _now;
        if (_dt >= 1500) {
            console.log('[JS] 心跳 dt=' + _dt + 'ms （渲染器主线程曾卡顿）');
        }
    }, 1000);
})();
window.__diag = { events: [], cap: 300, tokenN: 0, thinkN: 0 };
function diagEvent(name, extra) {
    try {
        var d = window.__diag;
        d.events.push({ t: Date.now() % 1000000, e: name, x: extra });
        if (d.events.length > d.cap) d.events.splice(0, d.events.length - d.cap);
    } catch (e) {}
}
function dumpDiag() {
    try {
        var c = {};
        var last = {};
        var evs = window.__diag.events;
        for (var i = 0; i < evs.length; i++) {
            var e = evs[i].e;
            c[e] = (c[e] || 0) + 1;
            last[e] = evs[i].x;   // 每类最后一条
        }
        return JSON.stringify({ ver: window.__APP_VER, n: evs.length,
                                counts: c, last: last,
                                recent: evs.slice(-30) });
    } catch (e) { return '{}'; }
}

// ★ 实时 DOM 体检：缓冲区字符 vs DOM 实际字符 vs 可见性
//   返回每个正文段/思考段的 {b:缓冲, d:DOM, h:高度, op:透明度, dis:display}
function probeStream(msgId) {
    try {
        var out = { id: msgId, buf: false, segs: [], thinks: [], raf: 0, due: 0 };
        var buf = messageBuffer[msgId];
        if (!buf) return JSON.stringify(out);
        out.buf = true;
        out.raf = buf.raf ? 1 : 0;
        out.due = buf.rafDue ? 1 : 0;
        buf.textSegs = buf.textSegs || [];
        buf.thinkSegs = buf.thinkSegs || [];
        var i, el;
        for (i = 0; i < buf.textSegs.length; i++) {
            el = buf.textSegs[i];
            var cs = (el.ownerDocument.defaultView.getComputedStyle)
                ? el.ownerDocument.defaultView.getComputedStyle(el) : null;
            out.segs.push({
                b: (el.__buf || '').length,
                d: (el.textContent || '').length,
                h: el.offsetHeight,
                op: cs ? cs.opacity : '?',
                dis: cs ? cs.display : '?',
                child: el.childNodes.length
            });
        }
        for (i = 0; i < buf.thinkSegs.length; i++) {
            el = buf.thinkSegs[i];
            out.thinks.push({
                b: (el.__buf || '').length,
                d: (el.textContent || '').length,
                h: el.offsetHeight
            });
        }
        return JSON.stringify(out);
    } catch (e) {
        return JSON.stringify({ err: String(e) });
    }
}

var chatContainer = document.getElementById('chat-container');
var messageBuffer = {};
var longTextStore = {};
var finalContentStore = {};
var attachmentMetaStore = {};
function isNearBottom() {
    return (window.innerHeight + window.scrollY) >= (document.body.scrollHeight - 150);
}

// ==================== 自定义滚动条镜像上报 ====================
function getScroller() {
    return document.scrollingElement || document.documentElement;
}

function webScrollTo(y) {
    getScroller().scrollTop = y;
}

function reportWebScroll() {
    if (window.bridge && window.bridge.onScrollChanged) {
        var se = getScroller();
        window.bridge.onScrollChanged(se.scrollTop, se.scrollHeight, se.clientHeight);
    }
}
document.addEventListener('scroll', function() {
    requestAnimationFrame(reportWebScroll);
}, { passive: true, capture: true });
window.addEventListener('resize', function() {
    requestAnimationFrame(reportWebScroll);
});
document.addEventListener('DOMContentLoaded', function() {
    setTimeout(reportWebScroll, 300);
});

// ==================== Markdown 渲染器配置 ====================
function escapeHtml(s) {
    return String(s == null ? '' : s)
        .replace(/&/g, '&amp;')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;')
        .replace(/"/g, '&quot;');
}

function safeHtml(html) {
    if (typeof window !== 'undefined' && window.DOMPurify) {
        return DOMPurify.sanitize(html, { ADD_TAGS: ['details', 'summary'] });
    }
    return html;
}

var renderer = new marked.Renderer();

renderer.code = function(obj) {
    var code = (typeof obj === 'string') ? obj : (obj.text || '');
    var lang = (typeof obj === 'string') ? (arguments[1] || '') : (obj.lang || '');
    var langLabel = lang ? lang : 'code';
    var isSvg = String(lang || '').trim().toLowerCase() === 'svg';
    var svgBtnHtml = isSvg
        ? '<button class="svg-render-btn" title="渲染为 SVG 图像（透明背景）">绘制</button>'
        : '';
    var safeCode = escapeHtml(code);
    var safeLang = escapeHtml(lang);
    var safeLangLabel = escapeHtml(langLabel);
    return '<div class="code-block-wrapper">'
        + '<div class="code-header">'
        + '<span class="code-lang-label">' + safeLangLabel + '</span>'
        + '<div class="code-header-actions">'
        + '<button class="fold-btn">展开</button>'
        + '<button class="copy-btn">'
        + '<svg class="icon-copy" width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><rect x="9" y="9" width="13" height="13" rx="2" ry="2"/><path d="M5 15H4a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h9a2 2 0 0 1 2 2v1"/></svg>'
        + '<svg class="icon-check" width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" style="display:none"><polyline points="20 6 9 17 4 12"/></svg>'
        + '<span class="btn-text">复制</span>'
        + '</button>'
        + svgBtnHtml
        + '</div>'
        + '</div>'
        + '<pre class="code-body collapsed"><code class="language-' + safeLang + '">' + safeCode + '</code></pre>'
        + '</div>';
};

// 流式渲染是全量重渲，围栏未闭合的瞬态或回答中的无围栏 HTML 片段都会被打成活体 DOM。
// 覆盖 renderer.html，把一切裸 HTML 转义为可见文本。
renderer.html = function(html) {
    return escapeHtml(html);
};

marked.setOptions({ renderer: renderer, breaks: true });

// ==================== 🌟 公式渲染（KaTeX + 部分供应商单括号 [...] 格式） ====================
//
// 部分大模型提供商把块公式输出成单括号 [ ... ]（非标准 $$...$$），
// 前端原先无任何公式渲染。统一管线（包在 marked.parse 里，17+ 个调用点
// ——正文/思考/工具/压缩摘要——自动生效）：
//   extractMath: 冻结代码区 → 抽公式为占位符 → 还原代码
//   marked.parse: 正常 markdown 渲染（占位符当纯文本通过）
//   restoreMath: 占位符 → KaTeX HTML（throwOnError=false，流式半截公式红色自愈）
//   safeHtml(DOMPurify): 调用点原有逻辑，KaTeX 产物也过一遍消毒
//
// 块定界符: $$...$$、\[...\]、[ ... ]（供应商格式，严格启发式防误伤）
// 行内定界符: $...$（货币/空格守卫）、\(...\)

var _mathItems = [];

function _mathHasFeature(c) {
    // 数学特征：\ 命令、上下标、等号、矩阵 &、希腊字母
    return /\\[a-zA-Z]/.test(c) || /[_^]/.test(c) || /=/.test(c) || /&/.test(c)
        || /[\u0370-\u03FF]/.test(c);
}

function _putMath(tex, display) {
    _mathItems.push({ tex: tex, display: display });
    return (display ? '@@KBMA' : '@@KMIA') + (_mathItems.length - 1) + '@@';
}

function _katexRender(tex, display) {
    if (typeof katex === 'undefined') return escapeHtml(tex);
    try {
        return katex.renderToString(tex, { displayMode: display, throwOnError: false, errorColor: '#cf1322' });
    } catch (e) {
        return escapeHtml(tex);
    }
}

function extractMath(text) {
    _mathItems = [];
    // ---- 1) 冻结代码区（围栏含流式未闭合瞬态 + 行内代码）：公式提取不碰代码 ----
    var codeFrozen = [];
    var s = String(text).replace(/```[\s\S]*?(?:```|$)|`[^`\n]*`/g, function(m){
        codeFrozen.push(m);
        return '@@KOCE' + (codeFrozen.length - 1) + '@@';
    });
    // ---- 2) 块 $$...$$ ----
    s = s.replace(/\$\$([\s\S]+?)\$\$/g, function(_, tex){ return _putMath(tex, true); });
    // ---- 3) 块 \[...\] ----
    s = s.replace(/\\\[[\s\S]+?\\\]/g, function(m){ return _putMath(m.slice(2, -2), true); });
    // ---- 4) 供应商单括号块 [ ... ]（严格启发式）----
    // 判公式条件：行首 [ + 行尾 ] + 后不紧跟 (（排除链接）+ 不含 http
    //           + 多行 或 含数学特征；[1] 编号/[a, b] 列表/单行链接全部排除
    {
        var out = '', pos = 0, n = s.length;
        while (pos < n) {
            var nl = s.indexOf('\n', pos);
            var lineEnd = nl === -1 ? n : nl;
            var line = s.substring(pos, lineEnd);
            var m = /^(\s*)\[/.exec(line);
            var consumed = false;
            if (m) {
                var searchFrom = pos + m[0].length;
                var brPos = pos + m[1].length;   // '[' 的位置（保留括号前空白，丢括号）
                var closeIdx = -1;
                var p2 = searchFrom;
                while (p2 < n) {
                    var nl2 = s.indexOf('\n', p2);
                    var le2 = nl2 === -1 ? n : nl2;
                    var l2 = s.substring(p2, le2);
                    var cm = l2.match(/\](\s*)$/);
                    if (cm) { closeIdx = p2 + cm.index; break; }
                    p2 = (nl2 === -1) ? n : nl2 + 1;
                }
                if (closeIdx > searchFrom) {
                    var content = s.substring(searchFrom, closeIdx);
                    var ok = content.trim() !== ''
                        && s.charAt(closeIdx + 1) !== '('
                        && content.indexOf('http') === -1
                        && content.indexOf('@@KOCE') === -1
                        && (content.indexOf('\n') !== -1 || _mathHasFeature(content.trim()));
                    if (ok) {
                        out += s.substring(pos, brPos) + _putMath(content, true);
                        pos = closeIdx + 1;
                        consumed = true;
                    }
                }
            }
            if (!consumed) {
                out += line + (nl === -1 ? '' : '\n');
                pos = nl === -1 ? n : nl + 1;
            }
        }
        s = out;
    }
    // ---- 5) 行内 \(...\) ----
    s = s.replace(/\\\(([\s\S]+?)\\\)/g, function(_, tex){ return _putMath(tex, false); });
    // ---- 6) 行内 $...$（守卫：首尾无空格、非纯数字、含数学特征 或 纯 ASCII 单词如 $x$）----
    s = s.replace(/\$([^\n$]+?)\$/g, function(full, tex){
        if (/^\s|\s$/.test(tex)) return full;       // 首尾空格 → 货币/普通
        if (/^[\d,.\s]+$/.test(tex)) return full;    // 纯数字 → 货币
        if (!_mathHasFeature(tex) && !/^[A-Za-z][A-Za-z0-9]*$/.test(tex.trim())) return full;
        return _putMath(tex, false);
    });
    // ---- 7) 还原代码区 ----
    s = s.replace(/@@KOCE(\d+)@@/g, function(_, i){ return codeFrozen[+i]; });
    return { md: s, items: _mathItems };
}

function restoreMath(html, items) {
    items = items || _mathItems;
    for (var i = 0; i < items.length; i++) {
        var tok = (items[i].display ? '@@KBMA' : '@@KMIA') + i + '@@';
        html = html.split(tok).join(_katexRender(items[i].tex, items[i].display));
    }
    return html;
}

// 🌟 统一拦截点：包 marked.parse，所有调用点（正文/流式/思考/工具/摘要）自动获得公式渲染
var _markedParseRaw = marked.parse.bind(marked);
marked.parse = function(text, opts) {
    if (typeof text !== 'string') return _markedParseRaw(text, opts);
    // 快速路径：无任何公式特征字符直接过（[...] 供应商格式也靠 [ 触发）
    if (text.indexOf('$') === -1 && text.indexOf('\\[') === -1
        && text.indexOf('\\(') === -1 && text.indexOf('[') === -1) {
        return _markedParseRaw(text, opts);
    }
    var ex = extractMath(text);
    return restoreMath(_markedParseRaw(ex.md, opts), ex.items);
};

// 🌟 流式稳定前缀防切分：前缀内有未闭合公式起点 → 返回应回退到的位置（0=无）
// （启发式；误判只延迟一帧固化，无功能影响）
function findUnclosedMathFrom(s) {
    var inFence = false, pos = 0, n = s.length;
    var dollarOpen = -1, bsOpen = -1, parenOpen = -1, inlineOpen = -1, bracketOpen = -1;
    while (pos < n) {
        var nl = s.indexOf('\n', pos);
        var lineEnd = nl === -1 ? n : nl + 1;
        var line = s.substring(pos, lineEnd);
        if (/^\s*(```|~~~)/.test(line)) inFence = !inFence;
        if (!inFence) {
            var i2 = 0;
            while ((i2 = line.indexOf('$$', i2)) !== -1) {
                dollarOpen = (dollarOpen === -1) ? (pos + i2) : -1;
                i2 += 2;
            }
            var ib = line.indexOf('\\[');
            if (ib !== -1) bsOpen = (bsOpen === -1) ? (pos + ib) : -1;
            if (line.indexOf('\\]') !== -1) bsOpen = -1;
            var ip = line.indexOf('\\(');
            if (ip !== -1) parenOpen = (parenOpen === -1) ? (pos + ip) : -1;
            if (line.indexOf('\\)') !== -1) parenOpen = -1;
            for (var k = 0; k < line.length; k++) {
                if (line.charAt(k) === '$'
                    && line.charAt(k + 1) !== '$'
                    && (k === 0 || line.charAt(k - 1) !== '$')) {
                    inlineOpen = (inlineOpen === -1) ? (pos + k) : -1;
                }
            }
            if (bracketOpen !== -1) {
                if (/\]\s*$/.test(line)) bracketOpen = -1;
            } else {
                var mb = /^(\s*)\[/.exec(line);
                if (mb && line.indexOf('](') === -1 && !/\]\s*$/.test(line)) {
                    // 行首 [ 未同行闭合、非链接；裸 [ 行或含数学特征才视为公式开
                    if (line.trim() === '[' || _mathHasFeature(line)) bracketOpen = pos;
                }
            }
        }
        pos = lineEnd;
    }
    var opens = [];
    if (dollarOpen !== -1) opens.push(dollarOpen);
    if (bsOpen !== -1) opens.push(bsOpen);
    if (parenOpen !== -1) opens.push(parenOpen);
    if (inlineOpen !== -1) opens.push(inlineOpen);
    if (bracketOpen !== -1) opens.push(bracketOpen);
    return opens.length ? Math.min.apply(null, opens) : 0;
}

// ==================== 全局事件委托 ====================
if (chatContainer) {
    chatContainer.addEventListener('click', function(e) {
        var target = e.target;

        // --- 1. 消息操作栏：复制整条消息 ---
        var copyMsgBtn = target.closest('.copy-msg-btn');
        if (copyMsgBtn) {
            var actionBar = copyMsgBtn.closest('.message-actions');
            if (actionBar) {
                var targetMsgId = actionBar.getAttribute('data-msg-id');
                var rawContent = (typeof finalContentStore !== 'undefined' && finalContentStore[targetMsgId]) || '';
                copyToClipboard(rawContent).then(function() {
                    var iconCopy = copyMsgBtn.querySelector('.icon-copy');
                    var iconCheck = copyMsgBtn.querySelector('.icon-check');
                    if (iconCopy && iconCheck) {
                        iconCopy.style.display = 'none';
                        iconCheck.style.display = 'inline';
                        setTimeout(function() {
                            iconCopy.style.display = 'inline';
                            iconCheck.style.display = 'none';
                        }, 2000);
                    }
                }).catch(function(err) {
                    console.error('复制失败:', err);
                });
            }
            return;
        }

        // --- 2. 消息操作栏：重新回答 ---
        var regenBtn = target.closest('.regenerate-btn');
        if (regenBtn) {
            var actionBar = regenBtn.closest('.message-actions');
            if (actionBar) {
                var targetMsgId = actionBar.getAttribute('data-msg-id');
                if (window.bridge && typeof window.bridge.onRegenerateClicked === 'function') {
                    window.bridge.onRegenerateClicked(targetMsgId);
                }
            }
            return;
        }

        // --- 3. 消息操作栏：压缩对话（预留） ---
        if (target.closest('.compress-btn')) {
            console.log('[JS]: 压缩对话功能预留');
            return;
        }

        // --- 4. 代码块复制 ---
        var copyBtn = target.closest('.copy-btn');
        if (copyBtn) {
            var wrapper = copyBtn.closest('.code-block-wrapper');
            var codeElem = wrapper ? wrapper.querySelector('code') : null;
            if (codeElem) {
                var rawCode = codeElem.textContent;
                copyToClipboard(rawCode).then(function() {
                    copyBtn.classList.add('copied');
                    var iconCopy = copyBtn.querySelector('.icon-copy');
                    var iconCheck = copyBtn.querySelector('.icon-check');
                    var btnText = copyBtn.querySelector('.btn-text');
                    if (iconCopy) iconCopy.style.display = 'none';
                    if (iconCheck) iconCheck.style.display = 'inline';
                    if (btnText) btnText.textContent = '已复制';
                    setTimeout(function() {
                        copyBtn.classList.remove('copied');
                        if (iconCopy) iconCopy.style.display = 'inline';
                        if (iconCheck) iconCheck.style.display = 'none';
                        if (btnText) btnText.textContent = '复制';
                    }, 2000);
                }).catch(function(err) {
                    console.error('代码复制失败:', err);
                });
            }
            return;
        }

        // --- 5. 代码块折叠 ---
        var foldBtn = target.closest('.fold-btn');
        if (foldBtn) {
            var wrapper = foldBtn.closest('.code-block-wrapper');
            var pre = wrapper ? wrapper.querySelector('.code-body') : null;
            if (pre) {
                var isCollapsed = pre.classList.toggle('collapsed');
                foldBtn.textContent = isCollapsed ? '展开' : '收起';
            }
            return;
        }

        // --- 5.5 SVG 代码块：绘制/源码 切换 ---
        var svgRenderBtn = target.closest('.svg-render-btn');
        if (svgRenderBtn) {
            var svgWrapper = svgRenderBtn.closest('.code-block-wrapper');
            if (svgWrapper && typeof toggleSvgRender === 'function') {
                toggleSvgRender(svgWrapper, svgRenderBtn);
            }
            return;
        }

        // --- 6. 附件卡片点击 (呼叫 Python 原生窗口) ---
        var card = target.closest('.long-text-card');
        if (card) {
            var attId = card.getAttribute('data-msg-id');
            var meta = attachmentMetaStore[attId];
            if (meta && window.bridge && typeof window.bridge.onAttachmentClicked === 'function') {
                window.bridge.onAttachmentClicked(JSON.stringify(meta));
            } else if (typeof showContentModal === 'function') {
                showContentModal(attId);
            }
            return;
        }

        // --- 7. 分支切换：左侧上一分支 ---
        var prevBranchBtn = target.closest('.prev-branch');
        if (prevBranchBtn && !prevBranchBtn.disabled) {
            var selector = prevBranchBtn.closest('.branch-selector');
            if (selector) {
                var msgId = selector.getAttribute('data-msg-id');
                if (window.bridge && typeof window.bridge.onBranchSwitch === 'function') {
                    window.bridge.onBranchSwitch(msgId, -1);
                }
            }
            return;
        }

        // --- 8. 分支切换：右侧下一分支 ---
        var nextBranchBtn = target.closest('.next-branch');
        if (nextBranchBtn && !nextBranchBtn.disabled) {
            var selector = nextBranchBtn.closest('.branch-selector');
            if (selector) {
                var msgId = selector.getAttribute('data-msg-id');
                if (window.bridge && typeof window.bridge.onBranchSwitch === 'function') {
                    window.bridge.onBranchSwitch(msgId, 1);
                }
            }
            return;
        }

        // --- 9. 优先检查：是否点击了“确认删除气泡”内部 ---
        var confirmPopover = target.closest('.delete-confirm-popover');
        if (confirmPopover) {
            var actionBar = confirmPopover.closest('.message-actions');
            if (actionBar) {
                var targetMsgId = actionBar.getAttribute('data-msg-id');
                if (window.bridge && typeof window.bridge.onDeleteMessageClicked === 'function') {
                    window.bridge.onDeleteMessageClicked(targetMsgId);
                }
            }
            confirmPopover.remove();
            e.stopPropagation();
            return;
        }

        // --- 10. 垃圾桶按钮点击：弹出确认气泡 ---
        var delBtn = target.closest('.delete-btn');
        if (delBtn) {
            document.querySelectorAll('.delete-confirm-popover').forEach(function(el) { el.remove(); });
            var popover = document.createElement('div');
            popover.className = 'delete-confirm-popover';
            var warnText = delBtn.classList.contains('user-delete-btn') ? '将连带下方对话一并删除，确认？' : '确认删除当前回答？';
            popover.innerHTML = '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><polyline points="20 6 9 17 4 12"></polyline></svg><span class="delete-confirm-text">' + warnText + '</span>';
            delBtn.appendChild(popover);
            e.stopPropagation();
            return;
        }

    });
}
document.addEventListener('click', function(e) {
    if (e.target.closest('.modal-close-btn')) { closeContentModal(); return; }
    var overlay = e.target.closest('.content-modal-overlay');
    if (overlay && e.target === overlay) { closeContentModal(); return; }
    document.querySelectorAll('.delete-confirm-popover').forEach(function(el) { el.remove(); });
});

// ==================== 剪贴板 ====================
function copyToClipboard(text) {
    var ta = document.createElement('textarea');
    ta.value = text;
    ta.style.cssText = 'position:fixed;left:-9999px;top:-9999px;opacity:0';
    document.body.appendChild(ta);
    ta.focus();
    ta.select();
    return new Promise(function(resolve, reject) {
        try { document.execCommand('copy'); resolve(); }
        catch (err) { reject(err); }
        finally { ta.remove(); }
    });
}

// ==================== 模态框 ====================
function showContentModal(msgId) {
    var text = longTextStore[msgId];
    if (!text) return;
    closeContentModal();

    var overlay = document.createElement('div');
    overlay.className = 'content-modal-overlay';

    var modal = document.createElement('div');
    modal.className = 'content-modal';

    var header = document.createElement('div');
    header.className = 'modal-header';
    var title = document.createElement('span');
    title.textContent = '文件内容';
    var closeBtn = document.createElement('button');
    closeBtn.className = 'modal-close-btn';
    closeBtn.innerHTML = '✕';
    header.appendChild(title);
    header.appendChild(closeBtn);

    var body = document.createElement('pre');
    body.className = 'modal-body';
    body.textContent = text;

    modal.appendChild(header);
    modal.appendChild(body);
    overlay.appendChild(modal);
    document.body.appendChild(overlay);
    requestAnimationFrame(function() { overlay.classList.add('visible'); });
}

function closeContentModal() {
    var overlay = document.querySelector('.content-modal-overlay');
    if (overlay) {
        overlay.classList.remove('visible');
        setTimeout(function() { overlay.remove(); }, 200);
    }
}

// ==================== 消息操作栏（只定义一次） ====================
function createActionBar(msgId) {
    var bar = document.createElement('div');
    bar.className = 'message-actions';
    bar.setAttribute('data-msg-id', msgId);

    var regenBtn = document.createElement('button');
    regenBtn.className = 'action-btn regenerate-btn';
    regenBtn.title = '重新回答';
    regenBtn.innerHTML = '<svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">'
        + '<path d="M1 4v6h6"/><path d="M3.51 15a9 9 0 1 0 2.13-9.36L1 10"/></svg>';

    var copyMsgBtn = document.createElement('button');
    copyMsgBtn.className = 'action-btn copy-msg-btn';
    copyMsgBtn.title = '复制';
    copyMsgBtn.innerHTML = '<svg class="icon-copy" width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">'
        + '<rect x="9" y="9" width="13" height="13" rx="2" ry="2"/>'
        + '<path d="M5 15H4a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h9a2 2 0 0 1 2 2v1"/></svg>'
        + '<svg class="icon-check" width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="#52c41a" stroke-width="2" style="display:none">'
        + '<polyline points="20 6 9 17 4 12"/></svg>';

    var compressBtn = document.createElement('button');
    compressBtn.className = 'action-btn compress-btn';
    compressBtn.title = '压缩对话';
    compressBtn.innerHTML = '<svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">'
        + '<polyline points="4 14 10 14 10 20"/><polyline points="20 10 14 10 14 4"/>'
        + '<line x1="14" y1="10" x2="21" y2="3"/><line x1="3" y1="21" x2="10" y2="14"/></svg>';

    var deleteBtn = document.createElement('button');
    deleteBtn.className = 'action-btn delete-btn';
    deleteBtn.title = '删除';
    deleteBtn.innerHTML = '<svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="3 6 5 6 21 6"></polyline><path d="M19 6v14a2 2 0 0 1-2 2H7a2 2 0 0 1-2-2V6m3 0V4a2 2 0 0 1 2-2h4a2 2 0 0 1 2 2v2"></path><line x1="10" y1="11" x2="10" y2="17"></line><line x1="14" y1="11" x2="14" y2="17"></line></svg>';
    deleteBtn.style.position = 'relative';

    bar.appendChild(regenBtn);
    bar.appendChild(copyMsgBtn);
    bar.appendChild(compressBtn);
    bar.appendChild(deleteBtn);

    return bar;
}

// ==================== 用户消息专属操作栏 ====================
function createUserActionBar(msgId) {
    var bar = document.createElement('div');
    bar.className = 'message-actions user-actions';
    bar.setAttribute('data-msg-id', msgId);
    bar.style.cssText = 'display: flex; justify-content: flex-end; margin-top: 8px; gap: 8px;';

    function createBtn(title, svgContent, isDelete) {
        var btn = document.createElement('button');
        btn.className = 'action-btn ' + (isDelete ? 'delete-btn user-delete-btn' : (title.includes('重') ? 'regenerate-btn' : 'copy-msg-btn'));
        btn.title = title;
        btn.innerHTML = svgContent;
        btn.style.cssText = 'background: transparent; border: none; cursor: pointer; padding: 6px; border-radius: 6px; display: inline-flex; align-items: center; justify-content: center; transition: background 0.2s;';
        btn.onmouseenter = function() {
            this.style.backgroundColor = isDelete ? '#fee2e2' : '#eaeaea';
            var svgs = this.querySelectorAll('svg');
            svgs.forEach(function(s) {
                if (!s.classList.contains('icon-check')) {
                    s.style.stroke = isDelete ? '#ef4444' : '#333333';
                }
            });
        };
        btn.onmouseleave = function() {
            this.style.backgroundColor = 'transparent';
            var svgs = this.querySelectorAll('svg');
            svgs.forEach(function(s) {
                if (!s.classList.contains('icon-check')) {
                    s.style.stroke = '#999999';
                }
            });
        };
        return btn;
    }

    var regenSvg = '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="#999999" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M1 4v6h6"/><path d="M3.51 15a9 9 0 1 0 2.13-9.36L1 10"/></svg>';
    var copySvg = '<svg class="icon-copy" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="#999999" stroke-width="2"><rect x="9" y="9" width="13" height="13" rx="2" ry="2"/><path d="M5 15H4a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h9a2 2 0 0 1 2 2v1"/></svg><svg class="icon-check" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="#52c41a" stroke-width="2" style="display:none"><polyline points="20 6 9 17 4 12"/></svg>';
    var delSvg = '<svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="#999999" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="3 6 5 6 21 6"></polyline><path d="M19 6v14a2 2 0 0 1-2 2H7a2 2 0 0 1-2-2V6m3 0V4a2 2 0 0 1 2-2h4a2 2 0 0 1 2 2v2"></path><line x1="10" y1="11" x2="10" y2="17"></line><line x1="14" y1="11" x2="14" y2="17"></line></svg>';

    var regenBtn = createBtn('重新提问', regenSvg, false);
    var copyMsgBtn = createBtn('复制提问', copySvg, false);
    var deleteBtn = createBtn('删除提问', delSvg, true);
    deleteBtn.style.position = 'relative';

    bar.appendChild(regenBtn);
    bar.appendChild(copyMsgBtn);
    bar.appendChild(deleteBtn);

    return bar;
}
// ==================== 消息创建 ====================
function createMessage(msgId, role, initialText, senderName, branchInfo) {
    console.log('[JS] createMessage id=' + msgId + ' role=' + role);
    initialText = initialText || '';
    senderName = senderName || '';
    var welcome = document.querySelector('.welcome-screen');
    if (welcome) {
        welcome.style.display = 'none';
    }
    var wrapper = document.createElement('div');
    wrapper.className = 'message-wrapper ' + role;
    wrapper.id = msgId;
    var avatar = document.createElement('div');
    avatar.className = 'avatar';
    avatar.innerText = role === 'user' ? 'U' : 'AI';
    var content = document.createElement('div');
    content.className = 'message-content';
    var nameLabel = document.createElement('div');
    nameLabel.className = 'sender-name';
    nameLabel.innerText = senderName || (role === 'user' ? 'You' : 'Assistant');

    if (role === 'assistant' && branchInfo && branchInfo.total > 1) {
        var branchUI = document.createElement('div');
        branchUI.className = 'branch-selector';
        branchUI.setAttribute('data-msg-id', msgId);
        var prevBtn = document.createElement('button');
        prevBtn.className = 'branch-btn prev-branch';
        prevBtn.innerHTML = '❮';
        prevBtn.disabled = (branchInfo.current <= 1);
        var textSpan = document.createElement('span');
        textSpan.className = 'branch-text';
        textSpan.innerText = branchInfo.current + ' / ' + branchInfo.total;
        var nextBtn = document.createElement('button');
        nextBtn.className = 'branch-btn next-branch';
        nextBtn.innerHTML = '❯';
        nextBtn.disabled = (branchInfo.current >= branchInfo.total);
        branchUI.appendChild(prevBtn);
        branchUI.appendChild(textSpan);
        branchUI.appendChild(nextBtn);
        nameLabel.appendChild(branchUI);
    }
    content.appendChild(nameLabel);
    var replyDiv = document.createElement('div');
    replyDiv.className = 'reply-content markdown-body';

    if (initialText) {
        if (role === 'user') {
            replyDiv.innerText = initialText;
        } else {
            // 🆕 助手纯文本消息（无时间线历史路径）也包进 md-segment → 与时间线路径同样有浅灰气泡背景
            var _tHtml = typeof marked !== 'undefined' ? safeHtml(marked.parse(initialText)) : safeHtml(initialText);
            replyDiv.innerHTML = '<div class="md-segment markdown-body">' + _tHtml + '</div>';
        }
    }
    content.appendChild(replyDiv);
    if (role === 'assistant') {
        if (typeof createActionBar === 'function') {
            content.appendChild(createActionBar(msgId));
        }
        if (typeof finalContentStore !== 'undefined') {
            finalContentStore[msgId] = initialText || '';
        }
    } else if (role === 'user') {
        if (typeof createUserActionBar === 'function') {
            content.appendChild(createUserActionBar(msgId));
        }
        if (typeof finalContentStore !== 'undefined') {
            finalContentStore[msgId] = initialText || '';
        }
    }
    wrapper.appendChild(avatar);
    wrapper.appendChild(content);

    if (typeof chatContainer !== 'undefined') {
        chatContainer.appendChild(wrapper);
    } else {
        document.getElementById('chat-container').appendChild(wrapper);
    }
    if (typeof messageBuffer !== 'undefined') {
        messageBuffer[msgId] = { reasoning: '', content: initialText, follow: true };
    }
    if (role === 'assistant') {
        wrapper.classList.add('streaming');
    }
    diagEvent('createMessage', { id: msgId, role: role, stream: role === 'assistant' });
    if (typeof softScroll === 'function') {
        softScroll();
    }
}

// ==================== 长文本消息 ====================
function createLongMessage(msgId, role, fullText, senderName, sizeKb) {
    senderName = senderName || 'You';
    var welcome = document.querySelector('.welcome-screen');
    if (welcome) welcome.style.display = 'none';

    longTextStore[msgId] = fullText;
    var lineCount = fullText.split('\n').length;

    var wrapper = document.createElement('div');
    wrapper.className = 'message-wrapper ' + role;
    wrapper.id = msgId;

    var avatar = document.createElement('div');
    avatar.className = 'avatar';
    avatar.innerText = 'U';

    var content = document.createElement('div');
    content.className = 'message-content';

    var nameLabel = document.createElement('div');
    nameLabel.className = 'sender-name';
    nameLabel.innerText = senderName;
    content.appendChild(nameLabel);

    content.appendChild(buildAttachmentCard(msgId, fullText, sizeKb, lineCount));

    wrapper.appendChild(avatar);
    wrapper.appendChild(content);
    chatContainer.appendChild(wrapper);

    messageBuffer[msgId] = { reasoning: '', content: '', follow: true };
    softScroll();
}

// ==================== 带附件的用户消息 ====================
function createUserMessageWithAttachments(msgId, plainText, attachments) {
    var welcome = document.querySelector('.welcome-screen');
    if (welcome) welcome.style.display = 'none';

    var wrapper = document.createElement('div');
    wrapper.className = 'message-wrapper user';
    wrapper.id = msgId;

    var avatar = document.createElement('div');
    avatar.className = 'avatar';
    avatar.innerText = 'U';

    var content = document.createElement('div');
    content.className = 'message-content';

    var nameLabel = document.createElement('div');
    nameLabel.className = 'sender-name';
    nameLabel.innerText = 'You';
    content.appendChild(nameLabel);

    var cardsContainer = document.createElement('div');
    cardsContainer.className = 'attachments-container';
    for (var i = 0; i < attachments.length; i++) {
        var att = attachments[i];
        var attId = msgId + '-att-' + i;
        longTextStore[attId] = att.content;
        attachmentMetaStore[attId] = att;
        cardsContainer.appendChild(buildAttachmentCard(attId, att.content, att.size_kb, att.lines, att.name, att.type, att.pages, att.mode));
    }
    content.appendChild(cardsContainer);

    if (plainText && plainText.trim()) {
        var replyDiv = document.createElement('div');
        replyDiv.className = 'reply-content markdown-body';
        replyDiv.innerText = plainText;
        content.appendChild(replyDiv);
    }

    content.appendChild(createUserActionBar(msgId));

    wrapper.appendChild(avatar);
    wrapper.appendChild(content);
    chatContainer.appendChild(wrapper);

    messageBuffer[msgId] = { reasoning: '', content: '', follow: true };
    softScroll();
}

// ==================== 附件卡片构建器 ====================
function buildAttachmentCard(id, text, sizeKb, lineCount, fileName, attType, pages, mode) {
    var card = document.createElement('div');
    card.className = 'long-text-card';
    card.setAttribute('data-msg-id', id);

    var icon = document.createElement('div');
    icon.className = 'card-icon';
    icon.innerHTML = '<svg width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#999" stroke-width="1.5">'
        + '<path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"/>'
        + '<polyline points="14 2 14 8 20 8"/>'
        + '<line x1="16" y1="13" x2="8" y2="13"/>'
        + '<line x1="16" y1="17" x2="8" y2="17"/></svg>';
    if (attType === 'pdf') {
        icon.innerHTML = '<svg width="24" height="24" viewBox="0 0 24 24" fill="#fff1f0" stroke="#cf1322" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round">'
            + '<path d="M4 19.5A2.5 2.5 0 0 1 6.5 17H20"/>'
            + '<path d="M6.5 2H20v20H6.5A2.5 2.5 0 0 1 4 19.5v-15A2.5 2.5 0 0 1 6.5 2z"/>'
            + '<line x1="9" y1="7" x2="16" y2="7"/>'
            + '<line x1="9" y1="11" x2="14" y2="11"/></svg>';
    }

    var info = document.createElement('div');
    info.className = 'card-info';
    var cardTitle = document.createElement('div');
    cardTitle.className = 'card-title';
    if (fileName) {
        cardTitle.textContent = fileName;
    } else {
        var preview = text.substring(0, 40).replace(/\n/g, ' ');
        if (text.length > 40) preview += '...';
        cardTitle.textContent = preview;
    }
    var cardMeta = document.createElement('div');
    cardMeta.className = 'card-meta';
    if (attType === 'pdf') {
        if (mode === 'image') {
            cardMeta.textContent = 'PDF 图片 · ' + sizeKb + ' KB · ' + (pages || 0) + ' 页 · ' + (lineCount || 0) + ' 张';
        } else {
            cardMeta.textContent = 'PDF 文本 · ' + sizeKb + ' KB · ' + (pages || 0) + ' 页';
        }
    } else {
        cardMeta.textContent = (fileName ? '' : 'TXT · ') + sizeKb + ' KB · ' + lineCount + ' 行';
    }

    info.appendChild(cardTitle);
    info.appendChild(cardMeta);
    card.appendChild(icon);
    card.appendChild(info);
    return card;
}

// ==================== SVG 代码块：绘制/源码 切换 ====================
function toggleSvgRender(wrapper, btn) {
    var codeElem = wrapper.querySelector('.code-body code');
    var foldBtn = wrapper.querySelector('.fold-btn');
    var isRenderMode = wrapper.classList.contains('svg-mode');

    if (isRenderMode) {
        wrapper.classList.remove('svg-mode');
        btn.textContent = '绘制';
        btn.classList.remove('active');
        if (foldBtn) foldBtn.disabled = false;
        var renderBody = wrapper.querySelector('.svg-render-body');
        if (renderBody) renderBody.remove();
    } else {
        if (!codeElem) return;
        var raw = codeElem.textContent;
        var safe = '';
        if (typeof DOMPurify !== 'undefined') {
            safe = DOMPurify.sanitize(raw, { USE_PROFILES: { svg: true, svgCustom: true } });
        }
        if (!safe) return;
        var body = document.createElement('div');
        body.className = 'svg-render-body';
        body.innerHTML = safe;
        wrapper.appendChild(body);
        wrapper.classList.add('svg-mode');
        btn.textContent = '源码';
        btn.classList.add('active');
        if (foldBtn) foldBtn.disabled = true;
    }
}

// ==================== 流式渲染（长上下文优化） ====================
// 🌟 核心优化：稳定前缀增量渲染 + rAF 批量，替代「每个 token 全量 marked.parse」。
//
// 原理：
//   - 把已流式内容切成 [稳定前缀 | 尾部] 两段。
//   - 稳定前缀 = 可以独立解析的完整 markdown 块（段落以空行结束、
//     代码围栏已闭合、行内代码反引号配对），解析一次后固化进 .md-stable，
//     之后永不再碰。
//   - 尾部（正在生长的那个块）每个 rAF 帧重渲一次。
//   - 多个 token 在一帧内到达时只渲一次（原来每 token 一次全量 parse → O(n²)；
//     现在每帧只 parse「尾部小段」+ 偶尔 parse「新完成的块」→ 近似 O(n)）。
//
// function computeSafeLen(s, stableLen) {
//     返回 s 中最长「可固化前缀」长度（> stableLen 才算有进展）。
//     规则：
//     1) 只算到最后一个完整行（末尾半行永远留尾部）
//     2) 代码围栏（```/~~~）闭合前，围栏及其所在块全部留尾部
//     3) 块边界 = 围栏外的空行、或刚闭合的围栏之后
//     4) 稳定区内行内代码反引号必须成对（不成对则回退到该行行首）
// }
function computeSafeLen(s, stableLen) {
    var lastNl = s.lastIndexOf('\n');
    var limit = lastNl >= 0 ? lastNl + 1 : 0;
    if (limit <= stableLen) return 0;

    var inFence = false;
    var candidate = 0;   // 最新的块边界位置（行首索引）
    var pos = 0;
    while (pos < limit) {
        var nl = s.indexOf('\n', pos);
        if (nl === -1 || nl >= limit) break;
        var line = s.substring(pos, nl);
        var next = nl + 1;
        var fence = /^\s*(```|~~~)/.test(line);
        if (!inFence && fence) {
            inFence = true;
        } else if (inFence && fence) {
            inFence = false;
            candidate = next;               // 围栏闭合后是块边界
        } else if (!inFence && line.trim() === '') {
            candidate = next;               // 空行是块边界
        }
        pos = next;
    }
    if (candidate > stableLen) {
        var seg = s.substring(0, candidate);
        var bt = (seg.match(/`/g) || []).length;
        if (bt % 2 === 1) {
            // 行内代码未闭合 → 回退到该段最后一行的行首
            var ln = seg.lastIndexOf('\n');
            candidate = ln >= 0 ? ln + 1 : 0;
        }
        // 🌟 公式感知：稳定区内有未闭合公式起点 → 回退到起点之前
        //（防公式前半被固化为纯文本、后半在尾部永远拼不上）
        var unc = findUnclosedMathFrom(seg);
        if (unc > 0) candidate = Math.min(candidate, unc);
    }
    return candidate > stableLen ? candidate : 0;
}

// 初始化/获取某个容器 div 的增量渲染状态
function mdStateOf(el) {
    if (!el.__mdState) {
        el.innerHTML = '';
        var stableEl = document.createElement('div');
        stableEl.className = 'md-stable';
        var tailEl = document.createElement('div');
        tailEl.className = 'md-tail';
        el.appendChild(stableEl);
        el.appendChild(tailEl);
        el.__mdState = { stableEl: stableEl, tailEl: tailEl,
                         stableLen: 0, lastTail: null, hlCount: 0 };
    }
    return el.__mdState;
}

// 对新固化进 .md-stable 的代码块做渐进高亮（只处理新增的）
function highlightNewCode(st) {
    if (typeof hljs === 'undefined') return;
    var codes = st.stableEl.querySelectorAll('pre code');
    for (var i = st.hlCount; i < codes.length; i++) {
        try { hljs.highlightElement(codes[i]); } catch (e) {}
    }
    st.hlCount = codes.length;
}

// 增量渲染：content 全量文本 → [固化段追加 + 尾部重渲]
function renderMarkdownStreaming(el, content) {
    var st = mdStateOf(el);
    var safe = computeSafeLen(content, st.stableLen);
    if (safe > st.stableLen) {
        var seg = content.slice(st.stableLen, safe);
        st.stableEl.insertAdjacentHTML('beforeend', safeHtml(marked.parse(seg)));
        st.stableLen = safe;
        highlightNewCode(st);
    }
    var tail = content.slice(st.stableLen);
    if (tail !== st.lastTail) {
        st.tailEl.innerHTML = safeHtml(marked.parse(tail));
        st.lastTail = tail;
    }
}

// ==================== 时间线渲染（思考 / 工具 / 正文 按事件顺序穿插） ====================
//
// 🌟 修复：原来「所有思考堆进顶部一个气泡、所有正文挤进一个块、
//    工具气泡全堆在末尾」。现在 .reply-content 就是时间线容器，
//    思考块 / 正文段 / 工具 chip 按事件到达顺序插入：
//
//   .reply-content
//     .think-block      ← 思考段 1
//     .tool-chip        ← 工具调用 1
//     .md-segment       ← 正文段 1（工具前模型说的话）
//     .think-block      ← 思考段 2
//     .md-segment       ← 正文段 2（最终回答）
//     .streaming-typing ← 光标（永远最后）

var CHEVRON_SVG = '<svg class="chev" viewBox="0 0 16 16" width="13" height="13" aria-hidden="true">'
    + '<path d="M5.5 3.5 L10.5 8 L5.5 12.5" fill="none" stroke="currentColor" '
    + 'stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"/></svg>';

function makeChevron() {
    var span = document.createElement('span');
    span.innerHTML = CHEVRON_SVG;
    return span.firstElementChild;
}

function makeThinkBlock(openNow, label) {
    var block = document.createElement('details');
    block.className = 'think-block';
    block.open = !!openNow;
    var summary = document.createElement('summary');
    summary.appendChild(makeChevron());
    var lab = document.createElement('span');
    lab.className = 'think-label';
    lab.textContent = label;
    summary.appendChild(lab);
    var tc = document.createElement('div');
    tc.className = 'think-content markdown-body';
    block.appendChild(summary);
    block.appendChild(tc);
    return block;
}

// 惰性把消息的 .reply-content 变成时间线容器
function ensureTimeline(wrapper, buf) {
    var replyDiv = wrapper.querySelector('.reply-content');
    if (!replyDiv) return null;
    if (!buf.timeline) {
        buf.timeline = true;
        buf.textSegs = [];
        buf.thinkSegs = [];
        var typing = document.createElement('span');
        typing.className = 'streaming-typing';
        typing.textContent = 'Chasing a shining star ';
        var dotEl = document.createElement('span');
        dotEl.className = 'typing-dot';
        dotEl.textContent = '●';
        typing.appendChild(dotEl);
        replyDiv.appendChild(typing);
        buf.typingEl = typing;
    }
    return replyDiv;
}

// ==================== 流式光标：Chasing a shining star ====================
// 光标（.streaming-typing）自消息第一个时间线事件出现即显示并循环脉冲（同款蓝 #3b82f6），
// 思考/工具/压缩/正文全程保持；finishMessage 时移除。无休眠态。

// 「思考结束」时立即就地固化进行中的思考块（不等消息结束）—— 激发→结束的态转换点：
// 一旦来了非思考事件（正文 token / 工具开始 / 压缩开始），当前思考段立即：
//   最终渲染（未闭合代码围栏补围栏）→ 删 __buf/__mdState 冻结 DOM → 去 .streaming-think
//   （蓝色脉冲消失）→ 折叠 → 标签「已完成深度思考」，并从 thinkSegs 摘除（渲染不再碰它）。
// 与 finishTimelineMessage 的固化逻辑同款（幂等兑底保留）。
function finalizeOpenThinkingBlocks(msgId) {
    var buf = messageBuffer[msgId];
    if (!buf || !buf.thinkSegs) return;
    for (var i = buf.thinkSegs.length - 1; i >= 0; i--) {
        var tc = buf.thinkSegs[i];
        var block = tc.closest ? tc.closest('.think-block') : null;
        if (!block || !block.classList.contains('streaming-think')) continue;
        var c = tc.__buf || '';
        if ((c.match(/```/g) || []).length % 2 !== 0) {
            tc.innerHTML = safeHtml('<div class="think-inner">' +
                marked.parse(c + '\n```') + '</div>');
        } else if (c && tc.innerHTML === '') {
            // rAF 还没跑过（极快结束）→ 一次性全量解析
            tc.innerHTML = safeHtml('<div class="think-inner">' +
                marked.parse(c) + '</div>');
        }
        delete tc.__mdState;
        delete tc.__buf;
        block.classList.remove('streaming-think');
        if (block.open) block.open = false;
        var lab = block.querySelector('.think-label');
        if (lab) lab.textContent = '已完成深度思考';
        buf.thinkSegs.splice(i, 1);
    }
}

// rAF 批量：一帧内到达的所有 token 只触发一次渲染
// 兜底：rAF 依赖合成器 BeginFrame（窗口隐藏/远程桌面/GPU 驱动异常时可能长时间
// 不出帧）→ 40ms 后若 rAF 仍未触发，用 setTimeout 强制同步渲染（≈25fps 下限）。
// 保证流式正文在任何渲染环境下都能实时显示。
function scheduleStreamingRender(msgId) {
    var buf = messageBuffer[msgId];
    if (!buf || buf.raf) return;
    buf.raf = requestAnimationFrame(function() {
        buf.raf = 0;
        if (buf.rafDue) { clearTimeout(buf.rafDue); buf.rafDue = 0; }
        buf.lastRenderAt = Date.now();
        doStreamingRender(msgId);
    });
    buf.rafDue = setTimeout(function() {
        if (buf.raf) {
            buf.raf = 0;
            buf.rafDue = 0;
            buf.lastRenderAt = Date.now();
            doStreamingRender(msgId);
        }
    }, 40);
}

// 若上一帧迟迟未触发（>60ms 无渲染）→ 放弃 rAF，本 token 直接同步渲染
function forceRenderIfStale(msgId) {
    var buf = messageBuffer[msgId];
    if (buf && buf.raf && buf.lastRenderAt && Date.now() - buf.lastRenderAt > 60) {
        buf.raf = 0;
        if (buf.rafDue) { clearTimeout(buf.rafDue); buf.rafDue = 0; }
        buf.lastRenderAt = Date.now();
        doStreamingRender(msgId);
    }
}

// ★ 终极兜底：同步渲染节流（≈33fps 上限）。
// 内容可见性不再依赖 rAF / 页面定时器 —— token 由 Python runJavaScript 送达，
// 本函数在同一 JS 任务内直接把内容写进 DOM。即使页面被判定隐藏
// （rAF 停发 + timer 钳制 1Hz）也能逐 token 实时显示。
var __lastSyncRender = {};
function syncRenderThrottled(msgId, minGapMs) {
    var now = Date.now();
    if (now - (__lastSyncRender[msgId] || 0) < (minGapMs == null ? 30 : minGapMs)) return;
    __lastSyncRender[msgId] = now;
    var buf = messageBuffer[msgId];
    if (!buf) return;
    doStreamingRender(msgId);
}

// Qt 看门狗入口：强制渲染（幂等，尾部无变化时开销极小）
function forceRenderNow(msgId) {
    var _frNow = Date.now();
    if (!window.__frLast || _frNow - window.__frLast > 1000) {
        window.__frLast = _frNow;
        console.log('[JS] forceRenderNow id=' + msgId + ' (看门狗)');
    }
    if (messageBuffer[msgId]) doStreamingRender(msgId);
}

function cancelStreamingRender(msgId) {
    var buf = messageBuffer[msgId];
    if (!buf) return;
    if (buf.raf) { cancelAnimationFrame(buf.raf); buf.raf = 0; }
    if (buf.rafDue) { clearTimeout(buf.rafDue); buf.rafDue = 0; }
}

// 每帧一次：增量渲染时间线上所有段 + 跟随滚动
// 兜底：任何渲染异常（marked 解析/HTML 注入）→ 对该段强制全量重解析，
//       保证流式正文永不因单次解析异常而永久空白。
function _fullRenderSegment(el, c, isThink) {
    if (!c) return;
    if (isThink) {
        el.innerHTML = safeHtml('<div class="think-inner">' + marked.parse(c) + '</div>');
    } else {
        el.innerHTML = safeHtml(marked.parse(c));
    }
    delete el.__mdState;  // 增量状态作废，下一帧从零重建
}
function doStreamingRender(msgId) {
    window.__renderN = (window.__renderN || 0) + 1;
    if (window.__renderN % 10 === 1) {
        console.log('[JS] render#' + window.__renderN + ' 开始 id=' + msgId);
    }
    var buf = messageBuffer[msgId];
    if (!buf) return;
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var wasNearBottom = isNearBottom();

    if (buf.timeline) {
        var i, seg, tc;
        for (i = 0; i < buf.textSegs.length; i++) {
            seg = buf.textSegs[i];
            try {
                renderMarkdownStreaming(seg, seg.__buf || '');
            } catch (e) {
                try { _fullRenderSegment(seg, seg.__buf || '', false); } catch (e2) {}
            }
        }
        for (i = 0; i < buf.thinkSegs.length; i++) {
            tc = buf.thinkSegs[i];
            try {
                renderMarkdownStreaming(tc, tc.__buf || '');
                tc.scrollTop = tc.scrollHeight;
            } catch (e) {
                try { _fullRenderSegment(tc, tc.__buf || '', true); } catch (e2) {}
            }
        }
    } else if (buf.content) {
        var replyDiv = wrapper.querySelector('.reply-content');
        if (replyDiv) {
            try {
                renderMarkdownStreaming(replyDiv, buf.content);
            } catch (e) {
                try { _fullRenderSegment(replyDiv, buf.content, false); } catch (e2) {}
            }
        }
    }

    // 跟随滚动（每帧最多一次；用户上滚自动暂停跟随）
    if (wasNearBottom && buf.follow !== false) {
        var anchor = document.getElementById('scroll-anchor');
        if (anchor) anchor.scrollIntoView({ behavior: 'auto', block: 'end' });
    }
}

function appendReasoning(msgId, token) {
    if (!messageBuffer[msgId]) return;
    var buf = messageBuffer[msgId];
    buf.reasoning += token;
    var wrapper = document.getElementById(msgId);
    if (!wrapper) { diagEvent('appendReasoning', 'NO_WRAPPER:' + msgId); return; }
    window.__diag.thinkN++;
    if (window.__diag.thinkN === 1 || window.__diag.thinkN % 25 === 0) {
        diagEvent('appendReasoning', 'n=' + window.__diag.thinkN);
    }
    wrapper.classList.add('streaming');
    var tl = ensureTimeline(wrapper, buf);
    if (!tl) return;
    // 续接规则：紧邻上一个块是「进行中」的思考块才续写，否则新开一段
    var last = buf.typingEl.previousElementSibling;
    var tc = (last && last.classList && last.classList.contains('streaming-think'))
        ? last.querySelector('.think-content') : null;
    if (!tc) {
        // 默认收起；进行中由 .streaming-think 蓝色呼吸动画提示（CSS）
        var block = makeThinkBlock(false, '深度思考');
        block.classList.add('streaming-think');
        tl.insertBefore(block, buf.typingEl);
        tc = block.querySelector('.think-content');
        buf.thinkSegs.push(tc);
    }
    tc.__buf = (tc.__buf || '') + token;
    console.log('[JS] think#' + window.__diag.thinkN + ' 段buf=' + tc.__buf.length + 'c dom=' + (tc.textContent || '').length + 'c h=' + tc.offsetHeight);
    syncRenderThrottled(msgId);   // ★ 同步通道
    scheduleStreamingRender(msgId);
}

function appendToken(msgId, token) {
    if (!messageBuffer[msgId]) return;
    var buf = messageBuffer[msgId];
    buf.content += token;
    var wrapper = document.getElementById(msgId);
    if (!wrapper) { diagEvent('appendToken', 'NO_WRAPPER:' + msgId); return; }
    window.__diag.tokenN++;
    if (window.__diag.tokenN === 1 || window.__diag.tokenN % 25 === 0) {
        diagEvent('appendToken', 'n=' + window.__diag.tokenN);
    }
    wrapper.classList.add('streaming');
    var tl = ensureTimeline(wrapper, buf);
    if (!tl) return;
    finalizeOpenThinkingBlocks(msgId);  // 首个正文 token → 思考必然已结束：思考段就地定格「已完成深度思考」
    // 续接规则：紧邻上一个块是正文段才续写，否则新开一段
    var last = buf.typingEl.previousElementSibling;
    var seg = (last && last.classList && last.classList.contains('md-segment'))
        ? last : null;
    if (!seg) {
        seg = document.createElement('div');
        seg.className = 'md-segment markdown-body';
        buf.textSegs.push(seg);
        seg.__buf = token;
        // ★ 根因修复（2026-07）：Chromium 布局失效 bug —— 空 .md-segment 进文档时
        //   匹配 :empty{display:none}，随后写入内容不重排，盒永久 0x0（正文不可见，
        //   切会话重渲因"带内容插入"而正常）。必须先同步渲染、带内容再插入。
        mdStateOf(seg);
        renderMarkdownStreaming(seg, seg.__buf);
        tl.insertBefore(seg, buf.typingEl);
    } else {
        seg.__buf = (seg.__buf || '') + token;
    }
    console.log('[JS] token#' + window.__diag.tokenN + ' 段buf=' + seg.__buf.length + 'c dom=' + (seg.textContent || '').length + 'c 段数=' + buf.textSegs.length + ' h=' + seg.offsetHeight);
    if (window.__diag.tokenN === 1 || window.__diag.tokenN % 25 === 0) {
        diagEvent('tokenDOM', { buf: seg.__buf.length, dom: (seg.textContent || '').length });
    }
    syncRenderThrottled(msgId);   // ★ 同步通道：token 到 → 内容必现
    scheduleStreamingRender(msgId);  // rAF 通道：更平滑（环境允许时）
}

// ==================== 完成消息 ====================
function finishMessage(msgId) {
    console.log('[JS] finishMessage id=' + msgId);
    var wrapper = document.getElementById(msgId);
    if (!wrapper) { delete messageBuffer[msgId]; diagEvent('finish', 'NO_WRAPPER:' + msgId); return; }
    diagEvent('finish', { id: msgId });
    var buf = messageBuffer[msgId];
    cancelStreamingRender(msgId);

    if (buf && buf.timeline) {
        // ---- 时间线路径：各段原地冻结（不重排、不重渲） ----
        finishTimelineMessage(wrapper, buf);
    } else {
        // ---- 静态路径（历史 / 非流式） ----
        // --- A. 修复未闭合 Markdown（围栏奇数 → 补围栏后全量重渲一次）---
        var content = buf ? buf.content : '';
        var replyDiv = wrapper.querySelector('.reply-content');
        var codeBlockCount = (content.match(/```/g) || []).length;
        if (codeBlockCount % 2 !== 0) {
            content += '\n```';
            if (buf) buf.content = content;
            if (replyDiv) {
                delete replyDiv.__mdState;
                replyDiv.innerHTML = safeHtml(marked.parse(content));
            }
        } else if (replyDiv && replyDiv.__mdState) {
            // 正常路径：增量 DOM 已经完整，零全量重渲，保留用户的折叠状态
            delete replyDiv.__mdState;
        }

        // --- D. 折叠思考框（压缩气泡 .compaction-think 有自己名字，不碰） ---
        var thinkBlock = wrapper.querySelector('.think-block:not(.compaction-think)');
        if (thinkBlock && thinkBlock.open) {
            thinkBlock.open = false;
            var lab = thinkBlock.querySelector('.think-label');
            if (lab) lab.textContent = '已完成深度思考';
        }
        if (thinkBlock) {
            var tc = thinkBlock.querySelector('.think-content');
            if (tc && tc.__mdState) delete tc.__mdState;
        }
    }

    // --- B. 折叠代码块过渡 ---
    var collapsedBlocks = wrapper.querySelectorAll('.code-body.collapsed');
    collapsedBlocks.forEach(function(block) {
        block.classList.add('scroll-locked');
        block.scrollTop = block.scrollHeight;
    });

    // --- C. 移除 streaming（操作栏自动显示） ---
    wrapper.classList.remove('streaming');

    // --- E. 代码高亮（增量渲染已渐进高亮过的会被跳过？这里统一兜底一次） ---
    wrapper.querySelectorAll('pre code').forEach(function(block) {
        try { hljs.highlightElement(block); } catch(e) {}
    });

    // --- F. 等重排完成 ---
    requestAnimationFrame(function() {
        setTimeout(function() {
            collapsedBlocks.forEach(function(block) {
                if (block.classList.contains('collapsed')) {
                    block.classList.remove('scroll-locked');
                    block.scrollTop = block.scrollHeight;
                }
            });
            var anchor = document.getElementById('scroll-anchor');
            if (anchor) anchor.scrollIntoView({ behavior: 'smooth', block: 'end' });
        }, 50);
    });

    // --- G. 更新最终内容存储 + 清理帧任务 ---
    if (buf) {
        finalContentStore[msgId] = buf.content;
        if (buf.raf) { cancelAnimationFrame(buf.raf); buf.raf = 0; }
    }
    delete messageBuffer[msgId];

    // --- H. 刷新自定义滚动条 ---
    reportWebScroll();
}

// 时间线路径的收尾：逐段冻结
function finishTimelineMessage(wrapper, buf) {
    console.log('[JS] finishTimeline 正文段=' + (buf ? buf.textSegs.length : 0) +
                ' 思考段=' + (buf ? buf.thinkSegs.length : 0) +
                ' 正文总量=' + (buf && buf.content ? buf.content.length : 0) + 'c');
    // 收尾：取消未触发的 rAF / 兜底定时器
    if (buf.raf) { cancelAnimationFrame(buf.raf); buf.raf = 0; }
    if (buf.rafDue) { clearTimeout(buf.rafDue); buf.rafDue = 0; }
    // 正文段：围栏奇数 → 补围栏后重渲该段；偶数 → 增量 DOM 已完整，只固化尾部
    buf.textSegs.forEach(function(seg) {
        var c = seg.__buf || '';
        if ((c.match(/```/g) || []).length % 2 !== 0) {
            seg.innerHTML = safeHtml(marked.parse(c + '\n```'));
        } else if (seg.__mdState) {
            renderMarkdownStreaming(seg, c);
            delete seg.__mdState;
        } else if (c) {
            // rAF 还没跑过（极快响应 / offscreen）→ 一次性全量解析
            seg.innerHTML = safeHtml(marked.parse(c));
        }
        delete seg.__buf;
    });
    // 思考块：固化 + 折叠
    buf.thinkSegs.forEach(function(tc) {
        var c = tc.__buf || '';
        if ((c.match(/```/g) || []).length % 2 !== 0) {
            tc.innerHTML = safeHtml(marked.parse(c + '\n```'));
        } else if (c && tc.innerHTML === '') {
            // rAF 还没跑过（极快响应 / offscreen）→ 一次性全量解析
            tc.innerHTML = safeHtml('<div class="think-inner">' +
                marked.parse(c) + '</div>');
        }
        delete tc.__mdState;
        delete tc.__buf;
        var block = tc.closest('.think-block');
        if (block) {
            block.classList.remove('streaming-think');
            if (block.open) block.open = false;
            var lab = block.querySelector('.think-label');
            if (lab) lab.textContent = '已完成深度思考';
        }
    });
    // 未结束的工具 chip（中止/出错）
    wrapper.querySelectorAll('.tool-chip.streaming').forEach(function(ch) {
        ch.classList.remove('streaming');
        var st = ch.querySelector('.tool-chip-status');
        if (st && st.classList.contains('running')) {
            st.classList.remove('running');
            st.classList.add('fail');
            st.textContent = '✗ 已中断';
        }
    });
    // 移除流式光标
    if (buf.typingEl && buf.typingEl.parentNode) {
        buf.typingEl.parentNode.removeChild(buf.typingEl);
    }
    // finish 后正文段体检（人肉 debug：确认正文盒是否可见）
    buf.textSegs.forEach(function(seg, i) {
        try {
            var cs = window.getComputedStyle(seg);
            var r = seg.getBoundingClientRect();
            console.log('[JS] finishAudit 正文段' + i +
                ' h=' + seg.offsetHeight + ' connected=' + seg.isConnected +
                ' rect=' + Math.round(r.top) + '/' + Math.round(r.height) +
                ' display=' + cs.display + ' visibility=' + cs.visibility +
                ' opacity=' + cs.opacity +
                ' parent=' + (seg.parentElement ? seg.parentElement.className : 'NULL'));
        } catch (e) {
            console.log('[JS] finishAudit 正文段' + i + ' 异常 ' + e);
        }
    });
}

// ==================== 错误注入 ====================
function showError(msgId, errorText) {
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var contentDiv = wrapper.querySelector('.message-content');

    if (contentDiv.querySelector('.system-error')) return;

    var errDiv = document.createElement('div');
    errDiv.className = 'system-error';
    errDiv.innerText = errorText;

    var actionBar = contentDiv.querySelector('.message-actions');
    if (actionBar) {
        contentDiv.insertBefore(errDiv, actionBar);
    } else {
        contentDiv.appendChild(errDiv);
    }

    wrapper.classList.remove('streaming');

    if (messageBuffer[msgId]) {
        finalContentStore[msgId] = messageBuffer[msgId].content;
    }

    softScroll();
}

// ==================== 工具执行气泡（pi tool_execution_* 事件，按 call_id 对号入座） ====================
// 浅色气泡，类似思考气泡：默认收起，摘要只显示「执行了什么」；点开展开参数+输出
function _toolBrief(name, args) {
    // 从参数里提取一行人类可读的简述（如 bash 的 command、read 的 path）
    try {
        var a = JSON.parse(args);
        var brief = a.command || a.path || a.file || a.pattern || a.query || '';
        if (typeof brief !== 'string') brief = JSON.stringify(brief);
        brief = String(brief).replace(/\s+/g, ' ').trim();
        if (brief.length > 46) brief = brief.slice(0, 46) + '…';
        return brief;
    } catch (e) {
        return '';
    }
}

function _findChip(wrapper, callId) {
    if (callId) {
        var byId = wrapper.querySelector('.tool-chip[data-call-id="' + callId + '"]');
        if (byId) return byId;
    }
    // 兜底：没带 call_id 的旧事件 → 最后一个还在流式中的 chip
    var chips = wrapper.querySelectorAll('.tool-chip.streaming');
    return chips.length ? chips[chips.length - 1] : null;
}

// 工具 chip 构造器（流式/恢复/历史 三种场景共用）
// opts: {streaming: bool, ok: null|true|false, result: str}
function buildToolChip(callId, name, args, opts) {
    opts = opts || {};
    var chip = document.createElement('details');
    chip.className = 'tool-chip' + (opts.streaming ? ' streaming' : '');
    chip.setAttribute('data-tool', name);
    chip.setAttribute('data-call-id', callId || '');
    chip.open = false; // 默认收起，只显示执行了什么

    var sum = document.createElement('summary');
    sum.appendChild(makeChevron());
    var icon = document.createElement('span');
    icon.className = 'tool-chip-icon';
    icon.textContent = '⚙';
    var nameSpan = document.createElement('span');
    nameSpan.className = 'tool-chip-name';
    nameSpan.textContent = name;
    var brief = document.createElement('span');
    brief.className = 'tool-chip-brief';
    brief.textContent = _toolBrief(name, args);
    var status = document.createElement('span');
    if (opts.ok === null || opts.ok === undefined) {
        status.className = 'tool-chip-status running';
        status.textContent = '执行中…';
    } else if (opts.ok) {
        status.className = 'tool-chip-status ok';
        status.textContent = '✓ 完成';
        if (opts.result) {
            var fl = String(opts.result).split('\n')[0].replace(/\s+/g, ' ').trim();
            if (fl.length > 60) fl = fl.slice(0, 60) + '…';
            if (fl) { brief.textContent = fl; brief.classList.add('done'); }
        }
    } else {
        status.className = 'tool-chip-status fail';
        status.textContent = '✗ 失败';
    }
    sum.appendChild(icon);
    sum.appendChild(nameSpan);
    if (brief.textContent) sum.appendChild(brief);
    sum.appendChild(status);

    var body = document.createElement('div');
    body.className = 'tool-chip-body';
    if (args) {
        var argsLabel = document.createElement('div');
        argsLabel.className = 'tool-chip-label';
        argsLabel.textContent = '参数';
        var argsPre = document.createElement('pre');
        argsPre.className = 'tool-chip-pre tool-chip-args';
        argsPre.textContent = String(args).length > 1500 ? String(args).slice(0, 1500) + '…' : String(args);
        body.appendChild(argsLabel);
        body.appendChild(argsPre);
    }
    var liveLabel = document.createElement('div');
    liveLabel.className = 'tool-chip-label';
    liveLabel.textContent = '输出';
    var live = document.createElement('pre');
    live.className = 'tool-chip-pre tool-chip-live';
    body.appendChild(liveLabel);
    body.appendChild(live);

    chip.appendChild(sum);
    chip.appendChild(body);
    chip.__sum = sum;
    chip.__liveBuf = '';
    if (opts.ok === null || opts.ok === undefined || !opts.result) {
        // 运行中（或无结果）：输出区暂隐
        live.textContent = '执行中…';
        live.style.display = 'none';
        liveLabel.style.display = 'none';
    } else {
        // 已出结果：长结果默认尾部预览 + 「展开完整输出」按钮；
        // 耗时/超时徽章进摘要行
        _renderToolResultBody(chip, String(opts.result));
        _updateChipTimingSummary(chip, String(opts.result));
    }
    return chip;
}

// 从 bash 结果解析耗时与命中超时：
//   成功: "$ cmd\n<out>\n[exit 0] (1.2s)"   超时: "命令超时（>120s）已终止"
function _parseToolTiming(resultText) {
    var s = String(resultText || '');
    var dur = null, timeout = null;
    var m = /\[exit -?\d+\]\s*\((\d+(?:\.\d+)?)s\)/.exec(s);
    if (m) dur = parseFloat(m[1]);
    var t = /命令超时（>\s*(\d+)s）/.exec(s);  // 工具输出用全角括号
    if (t) timeout = parseInt(t[1], 10);
    return { dur: dur, timeout: timeout };
}

// 摘要行插入 耗时/超时 徽章（收起时也能看到执行了多久、是否超时）
function _updateChipTimingSummary(chip, resultText) {
    var tm = _parseToolTiming(resultText);
    if (tm.dur === null && tm.timeout === null) return;
    var sum = chip.__sum || chip.querySelector('summary');
    if (!sum) return;
    var status = sum.querySelector('.tool-chip-status');
    var insertAt = status || sum.lastElementChild;
    if (tm.dur !== null) {
        var timeEl = chip.querySelector('.tool-chip-time');
        if (!timeEl) {
            timeEl = document.createElement('span');
            timeEl.className = 'tool-chip-time';
            sum.insertBefore(timeEl, insertAt);
        }
        timeEl.textContent = '⏱ ' + tm.dur + 's';
    }
    if (tm.timeout !== null) {
        var tmoEl = chip.querySelector('.tool-chip-timeout');
        if (!tmoEl) {
            tmoEl = document.createElement('span');
            tmoEl.className = 'tool-chip-timeout';
            sum.insertBefore(tmoEl, insertAt);
        }
        tmoEl.textContent = '⏱ 超时 ' + tm.timeout + 's';
    }
}

// 工具结果正文：短结果完整显示；长结果默认只显示尾部 4000 字 +
// 「展开完整输出」按钮（再点收起）。chip.__fullResult 保存全文。
var TOOL_PREVIEW_CHARS = 4000;
function _updateExpandBtn(btn, full, expanded) {
    btn.textContent = expanded
        ? '⬇ 收起（回到尾部预览）'
        : '⬆ 展开完整输出（共 ' + full.length + ' 字）';
}
function _renderToolResultBody(chip, resultText) {
    var live = chip.querySelector('.tool-chip-live');
    if (!live) return;
    var label = live.previousElementSibling;
    var body = live.parentElement;
    var full = String(resultText || '');
    chip.__fullResult = full;
    chip.__expanded = false;
    var btn = chip.querySelector('.tool-expand-btn');
    if (!full.trim()) {
        if (label) label.style.display = 'none';
        live.style.display = 'none';
        if (btn) btn.remove();
        return;
    }
    if (label) label.style.display = 'block';
    live.style.display = 'block';
    live.classList.remove('tool-chip-full');
    if (full.length > TOOL_PREVIEW_CHARS) {
        live.textContent = '…\n' + full.slice(-TOOL_PREVIEW_CHARS);
        if (!btn) {
            btn = document.createElement('button');
            btn.className = 'tool-expand-btn';
            btn.type = 'button';
            body.insertBefore(btn, live);
        }
        _updateExpandBtn(btn, full, false);
        btn.onclick = function() {
            chip.__expanded = !chip.__expanded;
            if (chip.__expanded) {
                live.textContent = full;
                live.classList.add('tool-chip-full');
                _updateExpandBtn(btn, full, true);
            } else {
                live.textContent = '…\n' + full.slice(-TOOL_PREVIEW_CHARS);
                live.classList.remove('tool-chip-full');
                _updateExpandBtn(btn, full, false);
            }
        };
    } else {
        if (btn) btn.remove();
        live.textContent = full;
    }
}

function toolExecutionStarted(msgId, callId, name, args) {
    console.log('[JS] tool开始 name=' + name + ' call=' + callId + ' id=' + msgId);
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var contentDiv = wrapper.querySelector('.message-content');
    var buf = messageBuffer[msgId];

    var chip = buildToolChip(callId, name, args, {streaming: true, ok: null});

    // 🌟 插入到时间线当前位置（思考/正文之间，按事件顺序）；
    //    非流式消息（无 messageBuffer）退回气泡底部
    finalizeOpenThinkingBlocks(msgId);  // 工具开始 → 思考段就地定格「已完成深度思考」
    var replyDiv = contentDiv.querySelector('.reply-content');
    if (replyDiv && buf) {
        ensureTimeline(wrapper, buf);
        replyDiv.insertBefore(chip, buf.typingEl);
    } else {
        var actionBar = contentDiv.querySelector('.message-actions');
        if (actionBar) contentDiv.insertBefore(chip, actionBar);
        else contentDiv.appendChild(chip);
    }
    scheduleStreamingRender(msgId); // 触发一次滚动
}

function toolExecutionUpdated(msgId, callId, text) {
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var chip = _findChip(wrapper, callId);
    if (!chip) return;
    chip.__liveBuf = (chip.__liveBuf || '') + text;
    if (chip.__liveBuf.length > 4000) {
        chip.__liveBuf = chip.__liveBuf.slice(-4000);
    }
    // 只有展开时才实时刷新输出（收起时零 DOM 开销）
    if (chip.open) {
        var live = chip.querySelector('.tool-chip-live');
        live.style.display = 'block';
        live.textContent = chip.__liveBuf;
        live.previousElementSibling.style.display = 'block';
        var body = chip.querySelector('.tool-chip-body');
        body.scrollTop = body.scrollHeight;
    }
}

function toolExecutionTimed(msgId, callId, elapsed, timeout) {
    // 🆕 bash 运行中每秒读秒（Python 每秒推一次 = 唯一事实源）：
    // 摘要行显示 ⏱ 0/10s → 1/10s → 2/10s ...
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var chip = _findChip(wrapper, callId);
    if (!chip) return;
    var t = chip.querySelector('.tool-chip-livetimer');
    if (!t) {
        t = document.createElement('span');
        t.className = 'tool-chip-livetimer';
        var sum = chip.__sum || chip.querySelector('summary');
        if (sum) sum.appendChild(t);
    }
    t.textContent = '\u23f1 ' + elapsed + '/' + timeout + 's';
}

function toolExecutionFinished(msgId, callId, name, ok, text) {
    console.log('[JS] tool完成 name=' + name + ' ok=' + ok + ' 结果=' + (text ? text.length : 0) + 'c call=' + callId);
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var chip = _findChip(wrapper, callId);
    if (!chip) return;
    // 🆕 读秒停止：移除运行中计时，换成完成/超时徽章（_updateChipTimingSummary）
    var _lt = chip.querySelector('.tool-chip-livetimer');
    if (_lt) _lt.remove();
    chip.classList.remove('streaming');
    var status = chip.querySelector('.tool-chip-status');
    var outText = text || chip.__liveBuf || '';
    if (status) {
        status.classList.remove('running');
        status.classList.add(ok ? 'ok' : 'fail');
        status.textContent = ok ? '✓ 完成' : '✗ 失败';
    }
    // 摘要显示结果首行（收起时也能看到「执行了什么 + 得到什么」）
    var brief = chip.querySelector('.tool-chip-brief');
    if (ok && brief && outText) {
        var firstLine = outText.split('\n')[0].replace(/\s+/g, ' ').trim();
        if (firstLine.length > 60) firstLine = firstLine.slice(0, 60) + '…';
        brief.textContent = firstLine;
        brief.classList.add('done');
    }
    // 完整结果入正文 —— 不再依赖 chip 当前是否展开（修复「结束后展开为空」bug）；
    // 长结果默认显示尾部 4000 字 + 「展开完整输出」按钮
    if (outText) {
        _renderToolResultBody(chip, outText);
        _updateChipTimingSummary(chip, outText);
    }
    scheduleStreamingRender(msgId);
}

// ==================== 时间线恢复 / 历史渲染（持久化的 agent 时间线） ====================
// entries: [{"t":"think","text"}, {"t":"text","text"},
//           {"t":"tool","id","name","args","ok":null|bool,"result"}]
// liveMode=true  → 切回进行中的会话：块按流式状态建立，后续 token 无缝续流
// liveMode=false → 历史消息：静态渲染（思考折叠 / chip 定格 / 文本完整解析）
function renderTimelineEntries(msgId, entries, liveMode) {
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    var contentDiv = wrapper.querySelector('.message-content');
    var replyDiv = contentDiv.querySelector('.reply-content');
    if (!replyDiv) return;
    var buf = messageBuffer[msgId];

    if (liveMode && buf) {
        ensureTimeline(wrapper, buf);
    } else if (!liveMode) {
        // 静态：清掉 createMessage 预先渲染的聚合文本（时间线接管展示）
        replyDiv.innerHTML = '';
    }

    var textAll = '', thinkAll = '';
    entries.forEach(function(e) {
        if (e.t === 'think') {
            var block = makeThinkBlock(false, liveMode ? '深度思考' : '已完成深度思考');
            var tc = block.querySelector('.think-content');
            if (liveMode) {
                block.classList.add('streaming-think');
                tc.__buf = e.text || '';
                buf.thinkSegs.push(tc);
                replyDiv.insertBefore(block, buf.typingEl);
            } else {
                tc.innerHTML = safeHtml('<div class="think-inner">' +
                    marked.parse(e.text || '') + '</div>');
                replyDiv.appendChild(block);
            }
            thinkAll += e.text || '';
        } else if (e.t === 'text') {
            var seg = document.createElement('div');
            seg.className = 'md-segment markdown-body';
            if (liveMode) {
                seg.__buf = e.text || '';
                buf.textSegs.push(seg);
                if (seg.__buf) {
                    // ★ 同 appendToken：带内容再插入，规避 :empty 布局失效
                    mdStateOf(seg);
                    renderMarkdownStreaming(seg, seg.__buf);
                }
                replyDiv.insertBefore(seg, buf.typingEl);
            } else {
                seg.innerHTML = safeHtml(marked.parse(e.text || ''));
                replyDiv.appendChild(seg);
            }
            textAll += e.text || '';
        } else if (e.t === 'tool') {
            var chip = buildToolChip(e.id || '', e.name, e.args || '', {
                streaming: liveMode && e.ok === null,
                ok: e.ok === null ? null : !!e.ok,
                result: e.result || ''
            });
            if (liveMode) replyDiv.insertBefore(chip, buf.typingEl);
            else replyDiv.appendChild(chip);
        }
    });

    if (liveMode && buf) {
        // 缓冲区对齐：后续流式事件在此基础上继续累积（复制/入库不丢内容）
        buf.content = textAll;
        buf.reasoning = thinkAll;
        // ★ 恢复的内容立即同步上屏（不等待 rAF/timer）
        syncRenderThrottled(msgId, 0);
        scheduleStreamingRender(msgId);
    }
    diagEvent(liveMode ? 'restore' : 'history',
              { id: msgId, entries: entries.length, text: textAll.length,
                think: thinkAll.length, buf: !!buf });
}

// 切回进行中的会话：恢复时间线（后续 token 无缝续流）
function restoreStreamingTimeline(msgId, timelineJson) {
    try { console.log('[JS] restoreTimeline id=' + msgId + ' 条目=' + (JSON.parse(timelineJson) || []).length); } catch (e) {}
    try {
        var entries = JSON.parse(timelineJson);
        if (Array.isArray(entries) && entries.length) {
            renderTimelineEntries(msgId, entries, true);
        }
    } catch (e) {
        console.error('[JS]: restoreStreamingTimeline 解析失败', e);
    }
}

// 历史消息：静态时间线渲染
function renderTimelineHistory(msgId, timelineJson) {
    try { console.log('[JS] historyTimeline id=' + msgId + ' 条目=' + (JSON.parse(timelineJson) || []).length); } catch (e) {}
    try {
        var entries = JSON.parse(timelineJson);
        if (Array.isArray(entries) && entries.length) {
            renderTimelineEntries(msgId, entries, false);
            // 删除 buffer → finishMessage 不再全量重渲（避免破坏时间线 DOM），
            // 但仍会执行代码高亮/滚动等收尾
            delete messageBuffer[msgId];
        }
    } catch (e) {
        console.error('[JS]: renderTimelineHistory 解析失败', e);
    }
}

// ==================== 上下文压缩气泡（照抄深度思考气泡类配置，仅改名字和显示内容） ====================
// 🌟 不再自写结构 —— 复用 makeThinkBlock / .think-block / .streaming-think：
//   执行中：蓝色呼吸 + 三点动画（与深度思考完全一致）
//   位置：当前消息的 .reply-content 时间线内（流式光标之前）—— 时间线位置，不锁底
//   限高：.think-content max-height 400px + 滚动（CSS 已做）
//   完成：原地折叠，label 显示 前→后 token，内容为摘要全文（.think-inner，同深度思考固化）
function _fmtK(n) {
    if (n === null || n === undefined) return '?';
    return (n / 1000).toFixed(1) + 'k';
}

function compactionStarted(msgId, path) {
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    wrapper.classList.add('streaming');
    var buf = messageBuffer[msgId] || null;
    var tl, typingEl;
    if (buf) {
        tl = ensureTimeline(wrapper, buf);   // 惰性把 .reply-content 变时间线（建流式光标）
        typingEl = buf.typingEl;
    } else {
        tl = wrapper.querySelector('.reply-content');
        typingEl = tl ? tl.querySelector('.streaming-typing') : null;
    }
    if (!tl) return;
    finalizeOpenThinkingBlocks(msgId);  // 防御：压缩开始 → 若有进行中的思考段也先定格
    // —— 与 appendReasoning 新建思考块完全同款 ——
    var block = makeThinkBlock(false, '上下文压缩');
    block.classList.add('streaming-think', 'compaction-think');
    var inner = document.createElement('div');
    inner.className = 'think-inner';
    inner.textContent = '正在生成摘要…';
    block.querySelector('.think-content').appendChild(inner);
    if (typingEl && typingEl.parentNode === tl) {
        tl.insertBefore(block, typingEl);    // 时间线位置：流式光标之前
    } else {
        tl.appendChild(block);
    }
    reportWebScroll();
}

function compactionFinished(msgId, payload) {
    payload = payload || {};
    var wrapper = document.getElementById(msgId);
    if (!wrapper) return;
    // 精确锁定「仍在执行中」的压缩气泡（最后一条）——一轮内多次压缩时
    // 不会误定/重复定格旧气泡；都已完成时回退到最后一条（幂等）
    var blocks = wrapper.querySelectorAll('.compaction-think');
    var block = null;
    for (var bi = blocks.length - 1; bi >= 0; bi--) {
        if (blocks[bi].classList.contains('streaming-think')) { block = blocks[bi]; break; }
    }
    if (!block && blocks.length) block = blocks[blocks.length - 1];
    if (!block) return;   // 气泡未建（非激活会话）→ 丢弃
    // —— 与 finishTimelineMessage 固化思考块同款 ——
    block.classList.remove('streaming-think');
    if (block.open) block.open = false;
    var lab = block.querySelector('.think-label');
    var dur = (payload.duration_ms !== null && payload.duration_ms !== undefined)
        ? ' · ' + (payload.duration_ms / 1000).toFixed(1) + 's' : '';
    if (lab) {
        lab.textContent = payload.failed
            ? '上下文压缩 · 未执行' + dur
            : '已完成上下文压缩 · ' + _fmtK(payload.before)
              + ' → ' + _fmtK(payload.after) + dur;
    }
    var tc = block.querySelector('.think-content');
    if (tc) {
        tc.innerHTML = safeHtml('<div class="think-inner">' +
            marked.parse(payload.summary || '（无摘要内容）') + '</div>');
        delete tc.__mdState;
    }
    reportWebScroll();
}

// ==================== 系统提示（居中单行） ====================
function showSystemNote(text) {
    var note = document.createElement('div');
    note.className = 'system-note';
    note.textContent = text;
    var anchor = document.getElementById('scroll-anchor');
    if (anchor && anchor.parentNode === chatContainer) {
        chatContainer.insertBefore(note, anchor);
    } else {
        chatContainer.appendChild(note);
    }
    reportWebScroll();
}

// ==================== 滚动控制 ====================
var _softScrollPending = 0;
function softScroll() {
    // 🌟 rAF 节流：历史记录批量渲染时每帧最多滚一次
    if (_softScrollPending) return;
    _softScrollPending = requestAnimationFrame(function() {
        _softScrollPending = 0;
        var anchor = document.getElementById('scroll-anchor');
        if (anchor) {
            anchor.scrollIntoView({ behavior: 'smooth', block: 'end' });
        }
    });
}

// ==================== 登录/会话加载界面 ====================
function showLoadingOverlay() {
    var el = document.getElementById('session-loading');
    if (!el) return;
    el.classList.remove('hide');
    el.style.display = 'flex';
}
function hideLoadingOverlay() {
    var el = document.getElementById('session-loading');
    if (!el) return;
    el.classList.add('hide');
    setTimeout(function() { el.style.display = 'none'; }, 480);
}

// ==================== 历史记录与视图控制 ====================
function clearChat() {
    var bubbles = chatContainer.querySelectorAll('.message-wrapper, .system-note');
    bubbles.forEach(function(b) { b.remove(); });

    // 🌟 修复：attachmentMetaStore 之前漏清，切会话后附件卡片会指向旧元数据
    messageBuffer = {};
    longTextStore = {};
    finalContentStore = {};
    attachmentMetaStore = {};

    var welcome = document.querySelector('.welcome-screen');
    if (welcome) welcome.style.display = 'none';
    reportWebScroll();
}

function deleteMessage(msgId) {
    var wrapper = document.getElementById(msgId);
    if (wrapper) {
        wrapper.style.transition = "opacity 0.3s ease, transform 0.3s ease";
        wrapper.style.opacity = "0";
        wrapper.style.transform = "translateY(-10px)";
        setTimeout(function() { wrapper.remove(); }, 300);
    }
    delete messageBuffer[msgId];
    delete longTextStore[msgId];
    delete finalContentStore[msgId];
    setTimeout(reportWebScroll, 350);
}

function showWelcome() {
    var welcome = document.querySelector('.welcome-screen');
    if (welcome) welcome.style.display = 'flex';
    reportWebScroll();
}

// ==================== 历史记录专用：插入思考块 ====================
function insertThinkBlock(msgId, reasoningText) {
    var wrapper = document.getElementById(msgId);
    if (!wrapper) {
        console.error('[JS]: 找不到消息气泡 ' + msgId);
        return;
    }

    var contentDiv = wrapper.querySelector('.message-content');
    var replyDiv = contentDiv.querySelector('.reply-content');

    var thinkBlock = makeThinkBlock(false, '已完成深度思考');
    var thinkContent = thinkBlock.querySelector('.think-content');
    thinkContent.innerHTML = safeHtml('<div class="think-inner">' + marked.parse(reasoningText) + '</div>');

    contentDiv.insertBefore(thinkBlock, replyDiv);
}

// ==================== JS 引擎就绪标志 ====================
window.jsReady = true;
console.log('[JS]: 引擎已就绪');