Create a transformer for dates

didier/data/embeds/hydra/menu.py

@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import date
 from enum import Enum
 from typing import Optional, cast
 
@@ -105,7 +105,7 @@ class Menu(EmbedPydantic):
 
     @overrides
     def to_embed(self, **kwargs) -> discord.Embed:
-        day_dt: datetime = cast(datetime, kwargs.get("day_dt"))
+        day_dt: date = cast(date, kwargs.get("day_dt"))
         weekday = int_to_weekday(day_dt.weekday())
         formatted_date = f"{leading('0', str(day_dt.day))}/{leading('0', str(day_dt.month))}/{day_dt.year}"
 
@@ -119,7 +119,7 @@ class Menu(EmbedPydantic):
         return embed
 
 
-def no_menu_found(day_dt: datetime) -> discord.Embed:
+def no_menu_found(day_dt: date) -> discord.Embed:
     """Return a different embed if no menu could be found"""
     embed = discord.Embed(title="Menu", colour=discord.Colour.red())
     embed.description = f"Unable to retrieve menu for {day_dt.strftime('%d/%m/%Y')}."

didier/utils/discord/converters/time.py

@@ -0,0 +1,48 @@
+import contextlib
+from datetime import date, timedelta
+from typing import Optional
+
+from discord.ext.commands import ArgumentParsingError
+
+from didier.utils.types.datetime import (
+    forward_to_next_weekday,
+    parse_dm_string,
+    str_to_weekday,
+)
+
+__all__ = ["date_converter"]
+
+
+def date_converter(argument: Optional[str]) -> date:
+    """Converter to turn a string into a date"""
+    # Store original argument for error message purposes
+    original_argument = argument
+
+    # Default to today
+    if not argument:
+        return date.today()
+
+    argument = argument.lower()
+
+    # Manual offsets
+    if argument in (
+        "tomorrow",
+        "tmrw",
+        "morgen",
+    ):
+        return date.today() + timedelta(days=1)
+
+    if argument in ("overmorgen",):
+        return date.today() + timedelta(days=2)
+
+    # Weekdays passed in words
+    with contextlib.suppress(ValueError):
+        weekday = str_to_weekday(argument)
+        return forward_to_next_weekday(date.today(), weekday, allow_today=False)
+
+    # Date strings
+    with contextlib.suppress(ValueError):
+        return parse_dm_string(argument)
+
+    # Unparseable
+    raise ArgumentParsingError(f"Unable to interpret `{original_argument}` as a date.")

didier/utils/types/datetime.py

@@ -1,18 +1,91 @@
 import datetime
+import re
 import zoneinfo
+from typing import TypeVar, Union
 
-__all__ = ["LOCAL_TIMEZONE", "int_to_weekday", "str_to_date", "tz_aware_now"]
+__all__ = [
+    "LOCAL_TIMEZONE",
+    "forward_to_next_weekday",
+    "int_to_weekday",
+    "parse_dm_string",
+    "str_to_date",
+    "str_to_month",
+    "str_to_weekday",
+    "tz_aware_now",
+]
 
-from typing import Union
+DateType = TypeVar("DateType", datetime.date, datetime.datetime)
 
 LOCAL_TIMEZONE = zoneinfo.ZoneInfo("Europe/Brussels")
 
 
+def forward_to_next_weekday(day_dt: DateType, target_weekday: int, *, allow_today: bool = False) -> DateType:
+    """Forward a date to the next occurence of a weekday"""
+    if not 0 <= target_weekday <= 6:
+        raise ValueError
+
+    # Skip at least one day
+    if not allow_today:
+        day_dt += datetime.timedelta(days=1)
+
+    while day_dt.weekday() != target_weekday:
+        day_dt += datetime.timedelta(days=1)
+
+    return day_dt
+
+
 def int_to_weekday(number: int) -> str:  # pragma: no cover # it's useless to write a test for this
     """Get the Dutch name of a weekday from the number"""
     return ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"][number]
 
 
+def parse_dm_string(argument: str) -> datetime.date:
+    """Parse a string to [day]/[month]
+
+    The year is set to the current year by default, as this can be changed easily.
+
+    This supports:
+    - DD/MM
+    - DD (month defaults to current)
+    - DD [Dutch Month, possibly abbreviated]
+    - DD [English Month, possibly abbreviated]
+    - [Dutch Month, possibly abbreviated] DD
+    - [English Month, possibly abbreviated] DD
+    """
+    argument = argument.lower()
+    today = datetime.date.today()
+
+    # DD/MM
+    if "/" in argument:
+        spl = argument.split("/")
+        if len(spl) != 2:
+            raise ValueError
+
+        return datetime.date(day=int(spl[0]), month=int(spl[1]), year=today.year)
+
+    # Try to interpret text
+    spl = argument.split(" ")
+    if len(spl) != 2:
+        raise ValueError
+
+    # Day Month
+    match = re.search(r"\d+", spl[0]).group()
+    if match is not None:
+        day = int(match)
+        month = str_to_month(spl[1])
+        return datetime.date(day=day, month=month, year=today.year)
+
+    # Month Day
+    match = re.search(r"\d+", spl[0]).group()
+    if match is not None:
+        day = int(match)
+        month = str_to_month(spl[0])
+        return datetime.date(day=day, month=month, year=today.year)
+
+    # Unparseable
+    raise ValueError
+
+
 def str_to_date(date_str: str, formats: Union[list[str], str] = "%d/%m/%Y") -> datetime.date:
     """Turn a string into a DD/MM/YYYY date"""
     # Allow passing multiple formats in a list
@@ -28,6 +101,76 @@ def str_to_date(date_str: str, formats: Union[list[str], str] = "%d/%m/%Y") -> d
     raise ValueError
 
 
+def str_to_month(argument: str) -> int:
+    """Turn a string int oa month, bilingual"""
+    argument = argument.lower()
+
+    month_dict = {
+        # English
+        "january": 1,
+        "february": 2,
+        "march": 3,
+        "april": 4,
+        "may": 5,
+        "june": 6,
+        "july": 7,
+        # August is a prefix of Augustus so it is skipped
+        "september": 9,
+        "october": 10,
+        "november": 11,
+        "december": 12,
+        # Dutch
+        "januari": 1,
+        "februari": 2,
+        "maart": 3,
+        # April is the same in English so it is skipped
+        "mei": 5,
+        "juni": 6,
+        "juli": 7,
+        "augustus": 8,
+        # September is the same in English so it is skipped
+        "oktober": 10,
+        # November is the same in English so it is skipped
+        # December is the same in English so it is skipped
+    }
+
+    for key, value in month_dict.items():
+        if key.startswith(argument):
+            return value
+
+    raise ValueError
+
+
+def str_to_weekday(argument: str) -> int:
+    """Turn a string into a weekday, bilingual"""
+    argument = argument.lower()
+
+    weekday_dict = {
+        # English
+        "monday": 0,
+        "tuesday": 1,
+        "wednesday": 2,
+        "thursday": 3,
+        "friday": 4,
+        "saturday": 5,
+        "sunday": 6,
+        # Dutch
+        "maandag": 0,
+        "dinsdag": 1,
+        "woensdag": 2,
+        "donderdag": 3,
+        "vrijdag": 4,
+        "zaterdag": 5,
+        "zondag": 6,
+    }
+
+    for key, value in weekday_dict.items():
+        if key.startswith(argument):
+            return value
+
+    raise ValueError
+
+
 def tz_aware_now() -> datetime.datetime:
     """Get the current date & time, but timezone-aware"""
     return datetime.datetime.utcnow().replace(tzinfo=datetime.timezone.utc).astimezone(LOCAL_TIMEZONE)