Custom emoji support

app/utils/emoji.py

@@ -0,0 +1,45 @@
+import mimetypes
+import re
+import typing
+from pathlib import Path
+
+if typing.TYPE_CHECKING:
+    from app.activitypub import RawObject
+
+EMOJI_REGEX = re.compile(r"(:[\d\w]+:)")
+
+EMOJIS: dict[str, "RawObject"] = {}
+EMOJIS_BY_NAME: dict[str, "RawObject"] = {}
+
+
+def _load_emojis(root_dir: Path, base_url: str) -> None:
+    if EMOJIS:
+        return
+    for emoji in (root_dir / "app" / "static" / "emoji").iterdir():
+        mt = mimetypes.guess_type(emoji.name)[0]
+        if mt and mt.startswith("image/"):
+            name = emoji.name.split(".")[0]
+            ap_emoji: "RawObject" = {
+                "type": "Emoji",
+                "name": f":{name}:",
+                "updated": "1970-01-01T00:00:00Z",  # XXX: we don't track date
+                "id": f"{base_url}/e/{name}",
+                "icon": {
+                    "mediaType": mt,
+                    "type": "Image",
+                    "url": f"{base_url}/static/emoji/{emoji.name}",
+                },
+            }
+            EMOJIS[emoji.name] = ap_emoji
+            EMOJIS_BY_NAME[ap_emoji["name"]] = ap_emoji
+
+
+def tags(content: str) -> list["RawObject"]:
+    tags = []
+    added = set()
+    for e in re.findall(EMOJI_REGEX, content):
+        if e not in added and e in EMOJIS_BY_NAME:
+            tags.append(EMOJIS_BY_NAME[e])
+            added.add(e)
+
+    return tags