feat(feishu): render markdown replies as cards

channel/feishu/feishu_static_card.py

@@ -0,0 +1,46 @@
+"""Helpers for choosing the native Feishu delivery format for text replies."""
+
+import json
+import re
+from typing import Tuple
+
+
+_BLOCK_MARKDOWN = re.compile(
+    r"(?m)^\s{0,3}(?:#{1,6}\s|>\s|[-*+]\s|\d+[.)]\s|```|~~~)"
+)
+_INLINE_MARKDOWN = re.compile(r"(`[^`\n]+`|\*\*[^*\n]+\*\*|\[[^]\n]+\]\([^)\n]+\))")
+_TABLE_SEPARATOR = re.compile(r"(?m)^\s*\|?\s*:?-{3,}:?\s*(?:\|\s*:?-{3,}:?\s*)+\|?\s*$")
+
+
+def contains_markdown(text: str) -> bool:
+    """Return whether *text* contains syntax that benefits from card Markdown."""
+    if not text:
+        return False
+    return bool(
+        _BLOCK_MARKDOWN.search(text)
+        or _INLINE_MARKDOWN.search(text)
+        or _TABLE_SEPARATOR.search(text)
+    )
+
+
+def build_markdown_card(text: str) -> dict:
+    """Build an inline Card 2.0 payload with one Markdown element."""
+    return {
+        "schema": "2.0",
+        "config": {},
+        "body": {
+            "elements": [
+                {
+                    "tag": "markdown",
+                    "content": text,
+                }
+            ]
+        },
+    }
+
+
+def build_text_delivery(text: str, enabled: bool = True) -> Tuple[str, str]:
+    """Return the Feishu ``msg_type`` and serialized content for a text reply."""
+    if enabled and contains_markdown(text):
+        return "interactive", json.dumps(build_markdown_card(text), ensure_ascii=False)
+    return "text", json.dumps({"text": text}, ensure_ascii=False)