Added lilypond edition

folkugat_web/services/lilypond.py

@@ -0,0 +1,70 @@
+import asyncio
+import dataclasses
+import os
+import re
+from pathlib import Path
+from typing import Literal
+
+import aiofiles
+from folkugat_web.model.lilypond import RenderError
+from folkugat_web.model.temes import Tema
+from folkugat_web.services import files as files_service
+from folkugat_web.templates import templates
+
+SCORE_BEGINNING = "% --- SCORE BEGINNING --- %"
+
+RenderFormat = Literal["png"] | Literal["pdf"]
+
+
+def source_to_single_score(source: str, tema: Tema) -> str:
+    return templates.get_template("lilypond/single_score.ly").render(
+        score_beginning=SCORE_BEGINNING,
+        score_source=source,
+        tema=tema,
+    )
+
+
+async def render(source: str, fmt: RenderFormat, output_filename: Path | None = None) -> tuple[Path | None, list[RenderError]]:
+    input_filename = files_service.create_tmp_filename(extension=".ly")
+    async with aiofiles.open(input_filename, "w") as f:
+        _ = await f.write(source)
+
+    output_filename = output_filename or files_service.create_tmp_filename()
+
+    if fmt == "png":
+        proc = await asyncio.create_subprocess_exec(
+            "lilypond", "--png", "-o", output_filename, input_filename,
+            stdout=asyncio.subprocess.PIPE,
+            stderr=asyncio.subprocess.PIPE,
+        )
+    else:
+        proc = await asyncio.create_subprocess_exec(
+            "lilypond", "-o", output_filename, input_filename,
+            stdout=asyncio.subprocess.PIPE,
+            stderr=asyncio.subprocess.PIPE,
+        )
+
+    _stdout, stderr = await proc.communicate()
+
+    if proc.returncode:
+        esc_input_filename = re.escape(str(input_filename))
+        error_re = re.compile(rf"{esc_input_filename}:(?P<line>\d+):(?P<pos>\d+): error: (?P<error>.*)$")
+        error_matches = filter(None, map(error_re.match, stderr.decode("utf-8").splitlines()))
+        errors = map(lambda m: RenderError.from_dict(m.groupdict()), error_matches)
+        line_offset = source.splitlines().index(SCORE_BEGINNING) + 1
+        errors_offset = [dataclasses.replace(e, line=e.line - line_offset) for e in errors if e.line > line_offset]
+        return None, errors_offset
+
+    if fmt == "png":
+        # Check if the output generated multiple pages
+        pages = sorted(output_filename.parent.rglob(f"{output_filename.name}*.png"))
+        if len(pages) > 1:
+            output_filename = pages[0]
+            for page in pages[1:]:
+                os.remove(page)
+        else:
+            output_filename = output_filename.with_suffix(".png")
+    elif fmt == "pdf":
+        output_filename = output_filename.with_suffix(".pdf")
+
+    return output_filename, []