Add bundled bus fonts and shared font favorites

核桃派软件源代码/app/fonts/render_cache.py

@@ -0,0 +1,64 @@
+"""Version only thumbnails that use a bundled font; preserve scene revisions."""
+from __future__ import annotations
+
+import hashlib
+import json
+from pathlib import Path
+
+from app.persistence import atomic_write_bytes
+
+STAMP_SUFFIX = ".font-version"
+
+
+def scene_font_version(scene: dict, resolver) -> str | None:
+    owner = getattr(resolver, "__self__", None)
+    version_for = getattr(owner, "render_version", None)
+    if version_for is None:
+        return None
+    elements = scene.get("elements", []) if scene.get("version") == 1 else [
+        element for layer in scene.get("layers", []) if layer.get("type") == "text"
+        for element in layer.get("elements", [])
+    ]
+    versions = sorted({version for element in elements
+                       if (version := version_for(element.get("font", "default")))})
+    if not versions:
+        return None
+    return hashlib.sha256(json.dumps(versions, separators=(",", ":")).encode("ascii")).hexdigest()[:16]
+
+
+def stamp_path(path: Path) -> Path:
+    return path.with_name(path.name + STAMP_SUFFIX)
+
+
+def cache_stale(path: Path, scene: dict, resolver) -> bool:
+    version = scene_font_version(scene, resolver)
+    if version is None:
+        return False
+    try:
+        return stamp_path(path).read_text(encoding="ascii").strip() != version
+    except (OSError, UnicodeError):
+        return True
+
+
+def stamp_cache(path: Path, scene: dict, resolver) -> None:
+    version = scene_font_version(scene, resolver)
+    stamp = stamp_path(path)
+    if version is not None:
+        atomic_write_bytes(stamp, (version + "\n").encode("ascii"))
+    else:
+        stamp.unlink(missing_ok=True)
+
+
+def versioned_url(url: str, scene: dict, resolver) -> str:
+    version = scene_font_version(scene, resolver)
+    return url + f"&font_v={version}" if version else url
+
+
+def cached_versioned_url(url: str, path: Path) -> str:
+    try:
+        version = stamp_path(path).read_text(encoding="ascii").strip()
+    except (OSError, UnicodeError):
+        return url
+    if len(version) == 16 and all(ch in "0123456789abcdef" for ch in version):
+        return url + f"&font_v={version}"
+    return url