Add deterministic final DOCX RTL/layout pass

Author: jamshidimoh

tools/finalize_docx_rtl.py

@@ -0,0 +1,142 @@
+from __future__ import annotations
+
+from pathlib import Path
+import re
+import sys
+import tempfile
+import zipfile
+import xml.etree.ElementTree as ET
+
+W = "http://schemas.openxmlformats.org/wordprocessingml/2006/main"
+NS = {"w": W}
+ET.register_namespace("w", W)
+PERSIAN_FONT = "Noto Naskh Arabic"
+LATIN_FONT = "Noto Sans"
+FA_RE = re.compile(r"[\u0600-\u06FF\u0750-\u077F\u08A0-\u08FF\uFB50-\uFDFF\uFE70-\uFEFF]")
+
+
+def w(tag: str) -> str:
+    return f"{{{W}}}{tag}"
+
+
+def ensure(parent, tag: str):
+    node = parent.find(w(tag))
+    if node is None:
+        node = ET.SubElement(parent, w(tag))
+    return node
+
+
+def set_bool(parent, tag: str, enabled: bool) -> None:
+    node = parent.find(w(tag))
+    if enabled and node is None:
+        ET.SubElement(parent, w(tag))
+    elif not enabled and node is not None:
+        parent.remove(node)
+
+
+def set_jc(ppr, value: str) -> None:
+    jc = ensure(ppr, "jc")
+    jc.set(w("val"), value)
+
+
+def set_ind(ppr, first_line_twips: int = 0, left: int | None = None, right: int | None = None) -> None:
+    ind = ensure(ppr, "ind")
+    for attr in ("left", "right", "start", "end", "firstLine", "hanging"):
+        ind.attrib.pop(w(attr), None)
+    ind.set(w("firstLine"), str(first_line_twips))
+    if left is not None:
+        ind.set(w("left"), str(left))
+    if right is not None:
+        ind.set(w("right"), str(right))
+
+
+def paragraph_text(p) -> str:
+    return "".join((t.text or "") for t in p.findall(".//" + w("t")))
+
+
+def style_id(p) -> str:
+    ppr = p.find(w("pPr"))
+    if ppr is None:
+        return ""
+    pstyle = ppr.find(w("pStyle"))
+    return (pstyle.get(w("val"), "") if pstyle is not None else "")
+
+
+def is_code(p) -> bool:
+    sid = style_id(p).lower()
+    text = paragraph_text(p).strip()
+    return "code" in sid or text.startswith(("```", "$ ", ">> "))
+
+
+def has_drawing(p) -> bool:
+    return p.find(".//" + w("drawing")) is not None
+
+
+def fix_paragraph(p) -> None:
+    ppr = ensure(p, "pPr")
+    sid = style_id(p)
+    sid_l = sid.lower()
+    text = paragraph_text(p)
+    code = is_code(p)
+    caption = sid_l == "caption"
+    drawing = has_drawing(p)
+
+    set_bool(ppr, "bidi", not code)
+    set_bool(ppr, "widowControl", True)
+    if sid_l.startswith("heading"):
+        set_bool(ppr, "keepNext", True)
+
+    if code:
+        set_jc(ppr, "left")
+        set_ind(ppr, 0)
+    elif caption or drawing:
+        set_jc(ppr, "center")
+        set_ind(ppr, 0)
+    else:
+        set_jc(ppr, "right")
+        if sid_l.startswith("heading") or sid_l.startswith("list"):
+            set_ind(ppr, 0, left=110, right=310)
+        else:
+            set_ind(ppr, 238)
+
+    for r in p.findall(".//" + w("r")):
+        txt = "".join((t.text or "") for t in r.findall(".//" + w("t")))
+        rpr = ensure(r, "rPr")
+        rtl = bool(FA_RE.search(txt))
+        set_bool(rpr, "rtl", rtl)
+        lang = ensure(rpr, "lang")
+        lang.set(w("val"), "fa-IR" if rtl else "en-US")
+        rfonts = ensure(rpr, "rFonts")
+        rfonts.set(w("ascii"), LATIN_FONT)
+        rfonts.set(w("hAnsi"), LATIN_FONT)
+        rfonts.set(w("cs"), PERSIAN_FONT if rtl else LATIN_FONT)
+        rfonts.set(w("eastAsia"), LATIN_FONT)
+
+
+def fix_xml(data: bytes) -> bytes:
+    root = ET.fromstring(data)
+    for p in root.findall(".//" + w("p")):
+        fix_paragraph(p)
+    return ET.tostring(root, encoding="utf-8", xml_declaration=True)
+
+
+def finalize(path: Path) -> None:
+    with tempfile.TemporaryDirectory(prefix="docx-finalize-") as td:
+        tmp = Path(td) / path.name
+        with zipfile.ZipFile(path, "r") as zin, zipfile.ZipFile(tmp, "w", zipfile.ZIP_DEFLATED) as zout:
+            for item in zin.infolist():
+                data = zin.read(item.filename)
+                if item.filename == "word/document.xml" or item.filename.startswith("word/header") or item.filename.startswith("word/footer"):
+                    data = fix_xml(data)
+                zout.writestr(item, data)
+        tmp.replace(path)
+
+
+if __name__ == "__main__":
+    if len(sys.argv) != 2:
+        raise SystemExit("Usage: finalize_docx_rtl.py <docx>")
+    p = Path(sys.argv[1])
+    if not p.exists():
+        raise SystemExit(f"Missing DOCX: {p}")
+    finalize(p)
+    print(f"Finalized deterministic Persian RTL layout: {p}")