feat(anki): basic export

src/anki/typst_compiler.py

@@ -0,0 +1,61 @@
+import asyncio
+import os
+from typing import List
+
+from .flashcard import Flashcard
+
+default_preamble = """
+#set page(width: auto, height: auto, margin: (rest: 0%))
+#let flashcard(id, front, back) = {
+  strong(front)
+  [\\ ]
+  back
+}
+"""
+
+
+class TypstCompilationError(ValueError):
+    pass
+
+
+class TypstCompiler:
+    preamble: str
+    typst_cmd: str
+    typst_root_dir: str
+    max_processes: int
+
+    def __init__(self, typst_root_dir: str = ".", typst_cmd: str = "typst", preamble: str = None):
+        if preamble is None:
+            preamble = default_preamble
+        self.typst_cmd = typst_cmd
+        self.typst_root_dir = typst_root_dir
+        self.preamble = preamble
+        self.max_processes = round(os.cpu_count() * 1.5)
+
+    async def _compile(self, src: str) -> bytes:
+        proc = await asyncio.create_subprocess_shell(
+            f"{self.typst_cmd} compile - - --root {self.typst_root_dir} --format svg",
+            stdin=asyncio.subprocess.PIPE,
+            stdout=asyncio.subprocess.PIPE,
+            stderr=asyncio.subprocess.PIPE,
+        )
+        proc.stdin.write(bytes(src, encoding="utf-8"))
+        proc.stdin.close()
+        await proc.wait()
+        if err := await proc.stderr.read():
+            raise TypstCompilationError(bytes.decode(err, encoding="utf-8"))
+        return await proc.stdout.read()
+
+    async def _compile_flashcard(self, card: Flashcard):
+        front = await self._compile(self.preamble + "\n" + card.as_typst(True))
+        back = await self._compile(self.preamble + "\n" + card.as_typst(False))
+        card.set_svgs(front, back)
+
+    async def compile_flashcards(self, cards: List[Flashcard]):
+        semaphore = asyncio.Semaphore(self.max_processes)
+
+        async def compile_coro(card):
+            async with semaphore:
+                return await self._compile_flashcard(card)
+
+        return await asyncio.gather(*(compile_coro(card) for card in cards))