Cleanups and bugfixes for (#2 and #8)

modules/utils/event_utils.py

@@ -0,0 +1,46 @@
+from datetime import datetime
+from typing import Any, Dict
+from zoneinfo import ZoneInfo
+
+from bson import ObjectId
+from discord import (
+    ApplicationContext,
+)
+
+from modules.database import col_events
+
+
+async def validate_event_validity(
+    ctx: ApplicationContext,
+    name: str,
+    start_date: datetime | None,
+    finish_date: datetime | None,
+    guild_timezone: ZoneInfo,
+    event_id: ObjectId | None = None,
+) -> None:
+    if start_date > finish_date:
+        # TODO Make a nice message
+        await ctx.respond("Start date must be before finish date")
+        return
+
+    if start_date < datetime.now(tz=guild_timezone):
+        # TODO Make a nice message
+        await ctx.respond("Start date must not be in the past")
+        return
+
+    # TODO Add validation for concurrent events.
+    #  Only one event can take place at the same time.
+    query: Dict[str, Any] = {
+        "name": name,
+        "ended": None,
+        "ends": {"$gt": datetime.now(tz=ZoneInfo("UTC"))},
+        "is_cancelled": {"$ne": True},
+    }
+
+    if event_id is not None:
+        query["_id"] = {"$ne": event_id}
+
+    if (await col_events.find_one(query)) is not None:
+        # TODO Make a nice message
+        await ctx.respond("There can only be one active event with the same name")
+        return