fix(ai): les clics ne font plus sauter la conversation au bas (BUG-059); tableaux markdown corrects dans create_pdf (#92)

backend/tools/documents.py

@@ -153,24 +153,39 @@ def _markdown_to_flowables(content: str) -> list[tuple[str, str]]:
     return blocks
 
 
-@tool(
-    name="create_pdf",
-    description=(
-        "Create a .pdf document in a vault from markdown-ish content "
-        "(# headings + paragraphs). Use for printable deliverables."
-    ),
-    input_model=PdfInput,
-    risk=ToolRisk.WRITE,
-    requires_vault=True,
-)
-def create_pdf(ctx: ToolContext, params: PdfInput) -> dict[str, Any]:
-    """Render the content with reportlab and save the PDF into the vault."""
+def _render_markdown_pdf(content: str, title: str) -> bytes | None:
+    """Render markdown → HTML → PDF through the document-page pipeline.
+
+    Uses the same stack as the « Download PDF » button of the document viewer
+    (mistune with the table plugin + WeasyPrint print CSS), so tables, code
+    blocks and lists are laid out correctly. Returns ``None`` when WeasyPrint
+    is not importable (missing GTK on some hosts) so the caller can fall back
+    to the simplified reportlab renderer.
+    """
+    try:
+        import mistune
+
+        from backend.pdf_export import build_pdf_html, generate_pdf
+
+        renderer = mistune.create_markdown(
+            escape=False,
+            plugins=["table", "strikethrough", "footnotes", "task_lists"],
+        )
+        html = renderer(content)
+        return generate_pdf(build_pdf_html(html, title), title)
+    except Exception as e:
+        # WeasyPrint loads GTK lazily: a missing native library can surface at
+        # import OR render time. Fall back to the simple renderer either way.
+        logger.warning("WeasyPrint pipeline unavailable for create_pdf: %s", e)
+        return None
+
+
+def _render_reportlab_pdf(content: str, title: str) -> bytes:
+    """Fallback renderer (no WeasyPrint): headings + paragraphs, no tables."""
     from reportlab.lib.pagesizes import A4
     from reportlab.lib.styles import getSampleStyleSheet
     from reportlab.platypus import Paragraph, SimpleDocTemplate, Spacer
 
-    path = _check_extension(params.path, ".pdf")
-    text = params.content[:MAX_PDF_CHARS]
     styles = getSampleStyleSheet()
     style_map = {
         "P": styles["BodyText"],
@@ -179,10 +194,36 @@ def create_pdf(ctx: ToolContext, params: PdfInput) -> dict[str, Any]:
         "H3": styles["Heading3"],
     }
     buffer = io.BytesIO()
-    doc = SimpleDocTemplate(buffer, pagesize=A4, title=params.title[:200])
-    story: list[Any] = [Paragraph(saxutils.escape(params.title[:300]), styles["Title"])]
-    for style, line in _markdown_to_flowables(text):
+    doc = SimpleDocTemplate(buffer, pagesize=A4, title=title[:200])
+    story: list[Any] = [Paragraph(saxutils.escape(title[:300]), styles["Title"])]
+    for style, line in _markdown_to_flowables(content):
         story.append(Spacer(1, 4))
         story.append(Paragraph(saxutils.escape(line), style_map[style]))
     doc.build(story)
-    return _save(params.vault, path, buffer.getvalue(), params.overwrite)
+    return buffer.getvalue()
+
+
+@tool(
+    name="create_pdf",
+    description=(
+        "Create a .pdf document in a vault from markdown content (headings, "
+        "paragraphs, tables, code blocks, lists). Use for printable "
+        "deliverables; tables are laid out like the document-page PDF export."
+    ),
+    input_model=PdfInput,
+    risk=ToolRisk.WRITE,
+    requires_vault=True,
+)
+def create_pdf(ctx: ToolContext, params: PdfInput) -> dict[str, Any]:
+    """Render the content and save the PDF into the vault.
+
+    Primary path: mistune (tables) + WeasyPrint — identical to the viewer's
+    « Download PDF » export. Fallback (WeasyPrint unavailable): simplified
+    reportlab layout without tables.
+    """
+    path = _check_extension(params.path, ".pdf")
+    content = params.content[:MAX_PDF_CHARS]
+    pdf_bytes = _render_markdown_pdf(content, params.title[:300])
+    if pdf_bytes is None:
+        pdf_bytes = _render_reportlab_pdf(content, params.title[:300])
+    return _save(params.vault, path, pdf_bytes, params.overwrite)