rewrite: Reminders system.

bot/utils/transformers.py

@@ -0,0 +1,77 @@
+import discord
+from discord import app_commands as appcmds
+from discord.app_commands import Transformer
+from discord.enums import AppCommandOptionType
+
+from meta.errors import UserInputError
+
+from babel.translator import ctx_translator
+
+from .lib import parse_duration, strfdur
+from . import util_babel
+
+
+_, _p = util_babel._, util_babel._p
+
+
+class DurationTransformer(Transformer):
+    """
+    Duration parameter, with included autocompletion.
+    """
+
+    def __init__(self, multiplier=1):
+        # Multiplier used for a raw integer value
+        self.multiplier = multiplier
+
+    @property
+    def type(self):
+        return AppCommandOptionType.string
+
+    async def transform(self, interaction: discord.Interaction, value: str) -> int:
+        """
+        Returns the number of seconds in the parsed duration.
+        Raises UserInputError if the duration cannot be parsed.
+        """
+        translator = ctx_translator.get()
+        t = translator.t
+
+        if value.isdigit():
+            return int(value) * self.multiplier
+        duration = parse_duration(value)
+        if duration is None:
+            raise UserInputError(
+                t(_p('utils:parse_dur|error', "Cannot parse `{value}` as a duration.")).format(
+                    value=value
+                )
+            )
+        return duration or 0
+
+    async def autocomplete(self, interaction: discord.Interaction, partial: str):
+        """
+        Default autocomplete for Duration parameters.
+
+        Attempts to parse the partial value as a duration, and reformat it as an autocomplete choice.
+        If not possible, displays an error message.
+        """
+        translator = ctx_translator.get()
+        t = translator.t
+
+        if partial.isdigit():
+            duration = int(partial) * self.multiplier
+        else:
+            duration = parse_duration(partial)
+
+        if duration is None:
+            choice = appcmds.Choice(
+                name=t(_p(
+                    'util:Duration|acmpl|error',
+                    "Cannot extract duration from \"{partial}\""
+                )).format(partial=partial),
+                value=partial
+            )
+        else:
+            choice = appcmds.Choice(
+                name=strfdur(duration, short=False, show_days=True),
+                value=partial
+            )
+        return [choice]