Add script to extract abstract and amend Makefile target

Makefile

@@ -9,7 +9,7 @@ PDF_SUBMISSION := $(TEX_MAIN_SUBMISSION:.tex=.pdf)
 # Resources
 IMAGES := $(wildcard images/*.jpg images/*.pdf images/*.png)
 
-.PHONY: all grammar paper submission view-paper view-submission clean
+.PHONY: all grammar paper submission view-paper view-submission clean abstract
 
 all: ${PDF_SUBMISSION} ${PDF_PAPER}
 
@@ -31,9 +31,7 @@ ${PDF_SUBMISSION}: ${TEX_MAIN_SUBMISSION} ${IMAGES}
 	latexmk ${TEX_MAIN_SUBMISSION}
 
 abstract: ${TEX_MAIN_PAPER}
-	# check that pandoc exists
-	@pandoc --version
-	sed -n '/\\begin{abstract}/,/\\end{abstract}/p' $< | sed '/\\begin{abstract}/d; /\\end{abstract}/d' | pandoc -f latex -t gfm -o $@.md
+	./tools/extract-abstract.py -i $< -o $@.md
 
 paper: ${PDF_PAPER}
 

tools/extract-abstract.py

@@ -0,0 +1,112 @@
+#!/usr/bin/env python3
+
+import io
+import re
+
+import argparse
+import pypandoc
+import panflute
+
+# store command definitions
+cmd_defs: dict[str, str] = {}
+
+
+def extract_cmds(latex_content):
+    """Extract LaTeX command definitions."""
+
+    pattern = r'\\newdelimitedcommand{(\w+)}{(.+?)}'
+    matches = re.finditer(pattern, latex_content)
+
+    commands = {}
+
+    for match in matches:
+        command_name = match.group(1)
+        definition = match.group(2)
+        commands[command_name] = definition
+
+    return commands
+
+
+def find_and_replace_cmds(elem: panflute.Element, _):
+    """Find and replace LaTeX command definitions."""
+    if isinstance(elem, panflute.RawInline) and elem.format == "latex":
+        for command, definition in cmd_defs.items():
+            pattern = r'\\' + command + r'{}'
+            text = re.sub(pattern, definition, elem.text)
+
+            if elem.text != text:
+                return panflute.Str(text)
+
+    return elem
+
+
+def extract_abstract_from_meta(doc):
+    """Extract the abstract from metadata."""
+    if 'abstract' in doc.metadata:
+        abstract = doc.metadata['abstract']
+
+        # MetaBlocks are a list of block elements (e.g., Para, BulletList, etc.)
+        if isinstance(abstract, panflute.MetaBlocks):
+            return abstract.content
+        elif isinstance(abstract, panflute.MetaInlines):
+            return [panflute.Para(abstract)]
+
+    return None
+
+
+def finalize(doc):
+    """Replace document content with abstract when used a panflute filter finalize
+    function."""
+    abstract_blocks = extract_abstract_from_meta(doc)
+    if abstract_blocks:
+        # Replace document content with abstract blocks
+        doc.content = abstract_blocks
+    else:
+        doc.content = [panflute.Para(panflute.Str("No abstract found."))]
+
+
+def noop(elem, doc):
+    """Noop for block-level filtering in a panflute filter action."""
+    return None
+
+
+def main():
+    """
+    Export abstract as markdown from a LaTeX file with some support for replacing custom
+    LaTeX commands.
+    """
+    parser = argparse.ArgumentParser(
+        description=r'Export abstract from LaTeX file to markdown with \\newdelimitedcommand replaced'
+    )
+    parser.add_argument('-i', "--input_file", help='input LaTeX file')
+    parser.add_argument('-o', "--output_file", help='output abstract as markdown file')
+    args = parser.parse_args()
+
+    try:
+        with open(args.input_file, 'r', encoding='utf-8') as file:
+            content = file.read()
+            global cmd_defs
+            cmd_defs = extract_cmds(content)
+    except Exception as exc:
+        print(exc)
+        return
+
+    data = pypandoc.convert_file(
+        args.input_file, 'json', extra_args=['--from=latex+raw_tex']
+    )
+    content = io.StringIO(data)
+    doc = panflute.load(content)
+    doc = panflute.run_filter(noop, finalize=finalize, doc=doc)
+    doc = panflute.run_filter(find_and_replace_cmds, doc=doc)
+    md_content = panflute.convert_text(doc, 'panflute', 'markdown')
+
+    try:
+        with open(args.output_file, 'w', newline='', encoding='utf-8') as file:
+            file.write(str(md_content))
+    except Exception as exc:
+        print(exc)
+        return
+
+
+if __name__ == "__main__":
+    main()