feat: add support for RDL format codes

src/sphinx_peakrdl/markdown/render.py

@@ -1,18 +1,81 @@
 from typing import List
 import os
+import re
 
 from docutils import nodes
 from docutils.utils import new_document
 
 from .md_parsers import MD_DOCUTILS, MD_HTML
 
+
+def rdlfc_to_markdown(text: str) -> str:
+    """Convert RDL Format Code tags to Markdown equivalents.
+
+    Handles the subset of RDLFormatCode tags that have natural Markdown
+    representations.  Tags with no Markdown equivalent (e.g. [color], [size])
+    are stripped.
+    """
+    replacements = [
+        # Inline formatting
+        (r'\[b\](.*?)\[/b\]', r'**\1**'),
+        (r'\[i\](.*?)\[/i\]', r'*\1*'),
+        (r'\[u\](.*?)\[/u\]', r'<u>\1</u>'),
+        (r'\[code\](.*?)\[/code\]', r'`\1`'),
+
+        # Links
+        (r'\[url=([^\]]+)\](.*?)\[/url\]', r'[\2](\1)'),
+        (r'\[url\](.*?)\[/url\]', r'<\1>'),
+        (r'\[email\](.*?)\[/email\]', r'<mailto:\1>'),
+
+        # Images
+        (r'\[img\](.*?)\[/img\]', r'![](\1)'),
+
+        # Block-level
+        (r'\[br\]', '  \n'),
+        (r'\[p\]', '\n\n'),
+        (r'\[/p\]', '\n\n'),
+
+        # Escapes and whitespace
+        (r'\[lb\]', '['),
+        (r'\[rb\]', ']'),
+        (r'\[sp\]', '\u00a0'),
+        (r'\[quote\]', '"'),
+        (r'\[/quote\]', '"'),
+
+        # Strip tags with no Markdown equivalent
+        (r'\[color=[^\]]+\]', ''),
+        (r'\[/color\]', ''),
+        (r'\[size=[^\]]+\]', ''),
+        (r'\[/size\]', ''),
+    ]
+
+    for pattern, repl in replacements:
+        text = re.sub(pattern, repl, text, flags=re.DOTALL)
+
+    # Convert [list]/[*]/[/list] to Markdown bullet lists
+    text = _convert_lists(text)
+
+    return text
+
+
+def _convert_lists(text: str) -> str:
+    """Convert RDL [list]/[*]/[/list] tags to Markdown lists."""
+    # Remove [list] and [/list] tags, adding paragraph breaks
+    text = re.sub(r'\[list(?:=[^\]]+)?\]', '\n', text)
+    text = re.sub(r'\[/list\]', '\n', text)
+    # Convert [*] bullets to Markdown list items
+    text = re.sub(r'\[\*\]\s*', '\n- ', text)
+    return text
+
+
 def render_to_docutils(md_string: str, src_path: str, src_line_offset: int = 0) -> List[nodes.Element]:
     MD_DOCUTILS.options["document"] = new_document(src_path)
 
     env = {
         "relative-images": os.path.dirname(src_path)
     }
 
+    md_string = rdlfc_to_markdown(md_string)
     doc = MD_DOCUTILS.render(md_string, env)
     assert isinstance(doc, nodes.document)