fix(chat): export the complete conversation across PDF pages (#6921)

static/app.js

@@ -561,10 +561,21 @@ function initializeEventListeners() {
 
   // Export: PDF
   const exportPdfBtn = el('export-pdf-btn');
+  let preparingPdf = false;
   if (exportPdfBtn) {
-    exportPdfBtn.addEventListener('click', (e) => {
+    exportPdfBtn.addEventListener('click', async (e) => {
       e.stopPropagation();
       exportMenu.classList.remove('open');
+      if (preparingPdf) return;
+      preparingPdf = true;
+      try {
+        await sessionModule.prepareHistoryForPrint();
+      } catch (error) {
+        uiModule.showError(error?.message || 'Could not prepare the chat for PDF export.');
+        return;
+      } finally {
+        preparingPdf = false;
+      }
       const meta = sessionModule.getSessions().find(s => s.id === sessionModule.getCurrentSessionId());
       const sessionName = meta ? meta.name : 'Odysseus Chat';
       const originalTitle = document.title;

static/css/02-compare.css

@@ -1701,6 +1701,7 @@
 
     /* ── Print / PDF Export ── */
     @media print {
+      html, body { height: auto !important; overflow: visible !important; }
       body { background: #fff !important; color: #000 !important; }
       #sidebar, .sidebar, #icon-rail, .hamburger-btn, #sidebar-backdrop, .chat-input-bar, .input-bar-wrapper,
       #welcome-screen, .chat-top-bar, .chat-meta-overlay, .msg-footer,

static/js/sessions.js

@@ -353,36 +353,38 @@ function _installHistoryPager(id, pageInfo, modelName) {
     handler: null,
   };
 
-  const loadOlder = async () => {
+  const loadOlder = async (force = false) => {
-    if (!_historyPager || _historyPager.loading || _historyPager.done) return;
+    const pager = _historyPager;
-    if (_historyPager.sessionId !== currentSessionId) return;
+    if (!pager || pager.loading || pager.done) return;
-    if (box.scrollTop > 90) return;
+    if (pager.sessionId !== currentSessionId) return;
+    if (!force && box.scrollTop > 90) return;
 
-    const nextOffset = Math.max(0, _historyPager.offset - _historyPager.limit);
+    const nextOffset = Math.max(0, pager.offset - pager.limit);
-    const nextLimit = _historyPager.offset - nextOffset;
+    const nextLimit = pager.offset - nextOffset;
     if (nextLimit <= 0) {
-      _historyPager.done = true;
+      pager.done = true;
       return;
     }
 
-    _historyPager.loading = true;
+    pager.loading = true;
     const anchor = box.querySelector('.msg, .agent-thread, .gallery-bubble');
     const beforeHeight = box.scrollHeight;
     try {
-      const res = await fetch(_historyUrl(_historyPager.sessionId, { limit: nextLimit, offset: nextOffset }));
+      const res = await fetch(_historyUrl(pager.sessionId, { limit: nextLimit, offset: nextOffset }));
+      if (!res.ok) throw new Error(`Chat history request failed (HTTP ${res.status})`);
       const data = await res.json();
-      if (!_historyPager || _historyPager.sessionId !== currentSessionId) return;
+      if (_historyPager !== pager || pager.sessionId !== currentSessionId) return;
       const newEls = [];
       for (const msg of data.history || []) {
         if (msg.role !== 'user' && msg.role !== 'assistant') continue;
-        const els = _renderHistoryMessage(msg, _historyPager.modelName);
+        const els = _renderHistoryMessage(msg, pager.modelName);
         if (Array.isArray(els)) newEls.push(...els);
       }
       for (const el of newEls) {
         box.insertBefore(el, anchor || box.firstChild);
       }
-      _historyPager.offset = Number(data.offset || nextOffset);
+      pager.offset = Number(data.offset || nextOffset);
-      _historyPager.done = !data.has_more_before;
+      pager.done = !data.has_more_before;
       if (window.hljs) {
         newEls.forEach(el => el.querySelectorAll('pre code:not(.hljs)').forEach(block => window.hljs.highlightElement(block)));
       }
@@ -391,16 +393,42 @@ function _installHistoryPager(id, pageInfo, modelName) {
     } catch (e) {
       console.warn('Failed to load older chat history:', e);
     } finally {
-      if (_historyPager) _historyPager.loading = false;
+      pager.loading = false;
     }
   };
 
+  _historyPager.loadOlder = loadOlder;
   _historyPager.handler = () => {
-    if (box.scrollTop <= 90) loadOlder();
+    if (box.scrollTop <= 90 && _historyPager && !_historyPager.loading) {
+      _historyPager.pending = loadOlder();
+    }
   };
   box.addEventListener('scroll', _historyPager.handler, { passive: true });
 }
 
+export async function prepareHistoryForPrint() {
+  const pager = _historyPager;
+  if (!pager) return;
+  const ensureCurrentChat = () => {
+    if (_historyPager !== pager || currentSessionId !== pager.sessionId) {
+      throw new Error('Chat changed while preparing the PDF. Export again from the intended chat.');
+    }
+  };
+  while (!pager.done) {
+    await pager.pending;
+    ensureCurrentChat();
+    if (pager.done) break;
+    const previousOffset = pager.offset;
+    pager.pending = pager.loadOlder(true);
+    await pager.pending;
+    ensureCurrentChat();
+    if (!pager.done && pager.offset >= previousOffset) {
+      throw new Error('Could not load the complete chat for PDF export. Please try again.');
+    }
+  }
+  ensureCurrentChat();
+}
+
 function _getIncognitoIds() {
   try { return JSON.parse(sessionStorage.getItem(_INCOGNITO_SESSIONS_KEY) || '[]'); } catch { return []; }
 }
@@ -4061,6 +4089,7 @@ const sessionModule = {
   renderSessionList,
   loadSessions,
   selectSession,
+  prepareHistoryForPrint,
   createDirectChat,
   materializePendingSession,
   preMaterializePendingSession,

tests/test_chat_print_pagination.py

@@ -0,0 +1,61 @@
+"""The shipped CSS must print every message beyond the screen viewport."""
+
+import json
+import os
+import shutil
+import subprocess
+from pathlib import Path
+
+import pytest
+from pypdf import PdfReader
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+@pytest.mark.skipif(not shutil.which("node"), reason="node is required for Chromium printing")
+def test_chat_print_preserves_the_complete_transcript(tmp_path):
+    script = r'''
+      import fs from 'node:fs';
+      import path from 'node:path';
+      import { chromium } from 'playwright';
+      const origin = process.env.ODYSSEUS_TEST_STATIC_ORIGIN;
+      const source = fs.readFileSync('static/index.html', 'utf8');
+      const links = [...source.matchAll(/<link\b[^>]*rel="stylesheet"[^>]*>/g)]
+        .map(match => match[0]).join('\n');
+      const messages = Array.from({length: 24}, (_, index) => {
+        const marker = 'EXPORTSENTINEL' + String(index + 1).padStart(2, '0');
+        const paragraphs = Array.from({length:4}, () =>
+          '<p>This synthetic message must survive printing beyond the screen viewport. '
+          + 'Every paragraph belongs to the saved conversation.</p>').join('');
+        return `<div class="msg ${index % 2 ? 'msg-ai' : 'msg-user'}"><div class="body"><p>${marker}</p>${paragraphs}</div></div>`;
+      }).join('');
+      const browser = await chromium.launch({headless:true});
+      try {
+        const results=[];
+        for (const [layout,viewport] of [['desktop',{width:1440,height:1000}],['mobile',{width:390,height:844}]]) {
+          const page=await browser.newPage({viewport});
+          await page.goto(origin+'/static/css/00-tokens.css');
+          await page.setContent(`<html><head>${links}</head><body><main class="chat-container"><div id="chat-history">${messages}</div></main></body></html>`,{waitUntil:'load'});
+          await page.evaluate(()=>document.fonts.ready);
+          const file=path.join(process.env.ODYSSEUS_PDF_OUTPUT_DIR,layout+'.pdf');
+          await page.pdf({path:file,format:'A4',printBackground:true});
+          results.push({layout,file});
+          await page.close();
+        }
+        console.log(JSON.stringify(results));
+      } finally {await browser.close();}
+    '''
+    result = subprocess.run(
+        ["node", "--input-type=module", "-e", script], cwd=ROOT,
+        capture_output=True, text=True, timeout=90,
+        env={**os.environ, "ODYSSEUS_PDF_OUTPUT_DIR": str(tmp_path)},
+    )
+    assert result.returncode == 0, result.stderr
+    results = json.loads(result.stdout)
+    assert {row["layout"] for row in results} == {"desktop", "mobile"}
+    for row in results:
+        pdf = PdfReader(row["file"])
+        text = "".join("".join(page.extract_text().split()) for page in pdf.pages)
+        assert len(pdf.pages) > 1, row["layout"]
+        for index in range(1, 25):
+            assert f"EXPORTSENTINEL{index:02d}" in text, (row["layout"], index)