Add dynamic language

docs/examples/languages.rst

@@ -18,7 +18,7 @@ Modify language files
    - If you want to modify the English language file: ``ez_en.json``.
    - If you want to create a new language file: ``ez_[language].json``.
 
-   For example, if you want to create a French language file, the file name could be ``ez_fr.json``.
+   If you want to create a French language file, the file name could be ``ez_fr.json``.
 
 2. Search the :ref:`language files <language>` and find keys you want to override.
 
@@ -30,6 +30,15 @@ Modify language files
 
    bot = ezcord.Bot(language="fr")  # French (loaded from ez_fr.json)
 
+If your bot supports **multiple languages**, set ``language`` to ``auto`` to
+automatically detect the language. You can set a fallback language with ``default_language``.
+
+The fallback language is used when no language file is found for the detected language.
+
+.. code-block:: python
+
+   bot = ezcord.Bot(language="auto", default_language="en")
+
 
 .. _language:
 

ezcord/bot.py

@@ -19,10 +19,8 @@
     READY_TITLE,
     EzConfig,
     get_error_text,
-    load_lang,
     print_custom_ready,
     print_ready,
-    set_lang,
     t,
 )
 from .internal.config import Blacklist
@@ -76,10 +74,12 @@ class Bot(_main_bot):  # type: ignore
         Whether to send the full error traceback. If this is ``False``,
         only the most recent traceback will be sent. Defaults to ``False``.
     language:
-        The language to use for user output.
-
-        The default languages are  If you add your own language file as
-        described in :doc:`the language example </examples/languages>`, you can use that language as well.
+        The language to use for user output. If this is set to ``auto``,
+        the bot will use the language of the interaction locale whenever possible.
+    default_language:
+        The default language to use if the interaction locale is not available.
+        Defaults to ``"en"``. ``en`` and ``de`` are available by default, but you can add your own
+        language as described in :doc:`the language example </examples/languages>`.
     ready_event:
         The style for :meth:`on_ready_event`. Defaults to :attr:`.ReadyEvent.default`.
         If this is ``None``, the event will be disabled.
@@ -96,7 +96,8 @@ def __init__(
         error_webhook_url: str | None = None,
         ignored_errors: list[Any] | None = None,
         full_error_traceback: bool = False,
-        language: str = "en",
+        language: str = "auto",
+        default_language: str = "en",
         ready_event: ReadyEvent | None = ReadyEvent.default,
         **kwargs,
     ):
@@ -119,8 +120,9 @@ def __init__(
         self.error_webhook_url = error_webhook_url
         self.ignored_errors = ignored_errors or []
         self.full_error_traceback = full_error_traceback
-        load_lang(language)
-        set_lang(language) if language != {} else set_lang("en")
+
+        EzConfig.lang = language
+        EzConfig.default_lang = default_language
 
         self.error_event_added = False
         if error_handler or error_webhook_url:
@@ -433,20 +435,20 @@ async def _error_event(self, ctx, error: discord.DiscordException):
             or type(error) is commands.CheckFailure
         ):
             if self.error_handler:
-                await error_emb(ctx, t("no_user_perms"))
+                await error_emb(ctx, t("no_user_perms", i=ctx))
             return
 
         if isinstance(error, commands.CommandOnCooldown):
             if self.error_handler:
                 seconds = round(ctx.command.get_cooldown_retry_after(ctx))
-                cooldown_txt = t("cooldown", dc_timestamp(seconds))
-                await error_emb(ctx, cooldown_txt, title=t("cooldown_title"))
+                cooldown_txt = t("cooldown", dc_timestamp(seconds), i=ctx)
+                await error_emb(ctx, cooldown_txt, title=t("cooldown_title", i=ctx))
 
         elif isinstance(error, checks.BotMissingPermissions):
             if self.error_handler:
                 perms = "\n".join(error.missing_permissions)
-                perm_txt = f"{t('no_perms')} ```\n{perms}```"
-                await error_emb(ctx, perm_txt, title=t("no_perms_title"))
+                perm_txt = f"{t('no_perms', i=ctx)} ```\n{perms}```"
+                await error_emb(ctx, perm_txt, title=t("no_perms_title", i=ctx))
 
         else:
             if "original" in error.__dict__ and not self.full_error_traceback:
@@ -457,9 +459,9 @@ async def _error_event(self, ctx, error: discord.DiscordException):
                 error_msg = f"{error}"
 
             if self.error_handler:
-                error_txt = f"{t('error', f'```{error_msg}```')}"
+                error_txt = f"{t('error', f'```{error_msg}```', i=ctx)}"
                 try:
-                    await error_emb(ctx, error_txt, title=t("error_title"))
+                    await error_emb(ctx, error_txt, title=t("error_title", i=ctx))
                 except discord.HTTPException as e:
                     # ignore invalid interaction error, probably took too long to respond
                     if e.code != 10062:

ezcord/cogs/blacklist.py

@@ -6,7 +6,6 @@
 """
 
 import aiosqlite
-import discord
 
 from .. import emb
 from ..blacklist import _BanDB
@@ -36,7 +35,7 @@ async def _check_blacklist(interaction: discord.Interaction) -> bool:
         if EzConfig.blacklist.raise_error:
             raise Blacklisted()
         else:
-            await emb.error(interaction, t("no_perms"))
+            await emb.error(interaction, t("no_perms", i=interaction))
         raise ErrorMessageSent()
     return True
 

ezcord/cogs/help.py

@@ -82,7 +82,9 @@ def __init__(self, bot: Bot):
     async def help(self, ctx):
         embed = self.bot.help.embed
         if embed is None:
-            embed = discord.Embed(title=t("embed_title"), color=discord.Color.blue())
+            embed = discord.Embed(
+                title=t("embed_title", i=ctx.interaction), color=discord.Color.blue()
+            )
         else:
             interaction = ctx.interaction if PYCORD else ctx
             embed = replace_embed_values(embed, interaction)
@@ -120,7 +122,7 @@ async def help(self, ctx):
 
             desc = cog.description
             if not cog.description:
-                desc = t("default_description", name)
+                desc = t("default_description", name, i=ctx)
                 if not desc:
                     log.warning(
                         f"The default description for cog '{name}' is invalid. "
@@ -184,7 +186,7 @@ async def help(self, ctx):
                     embed.add_field(name=field_name, value=desc, inline=False)
 
         if len(options) == 0:
-            return await ctx.response.send_message(t("no_commands"), ephemeral=True)
+            return await ctx.response.send_message(t("no_commands", i=ctx), ephemeral=True)
         if len(options) > 25 or len(embed.fields) > 25:
             log.error(
                 f"Help command category limit reached. Only 25 out of {len(options)} are shown."
@@ -194,7 +196,7 @@ async def help(self, ctx):
 
         sorted_options = sorted(options, key=lambda x: [char for char in x.label if char.isalpha()])
         embed.fields = sorted(embed.fields, key=lambda x: x.name.lower())
-        view = CategoryView(sorted_options, self.bot, ctx.user, commands)
+        view = CategoryView(sorted_options, self.bot, ctx.user, commands, ctx)
         for button in self.bot.help.buttons:
             view.add_item(deepcopy(button))
         await ctx.response.send_message(view=view, embed=embed, ephemeral=self.bot.help.ephemeral)
@@ -207,8 +209,11 @@ def __init__(
         bot: Bot,
         member: discord.Member | discord.User,
         commands: dict[str, dict],
+        interaction,
     ):
-        super().__init__(min_values=1, max_values=1, placeholder=t("placeholder"), options=options)
+        super().__init__(
+            min_values=1, max_values=1, placeholder=t("placeholder", i=interaction), options=options
+        )
         self.bot = bot
         self.member = member
         self.commands = commands
@@ -228,7 +233,7 @@ def get_mention(self, cmd) -> str:
 
     async def callback(self, interaction: discord.Interaction):
         if self.bot.help.author_only and interaction.user != self.member:
-            return await emb.error(interaction, t("wrong_user"))
+            return await emb.error(interaction, t("wrong_user", i=interaction))
 
         cmds = self.commands[self.values[0]]
         title = self.values[0].title()
@@ -296,9 +301,9 @@ async def callback(self, interaction: discord.Interaction):
                     break
 
         if len(commands) == 0:
-            embed.description = t("no_commands")
+            embed.description = t("no_commands", i=interaction)
 
-        view = CategoryView(self.options, self.bot, self.member, self.commands)
+        view = CategoryView(self.options, self.bot, self.member, self.commands, interaction)
         for button in self.bot.help.buttons:
             view.add_item(deepcopy(button))
         await interaction.response.edit_message(embed=embed, view=view)
@@ -311,10 +316,11 @@ def __init__(
         bot: Bot,
         member: discord.Member | discord.User,
         commands: dict[str, dict],
+        interaction: discord.Interaction,
     ):
         if PYCORD:
             super().__init__(timeout=bot.help.timeout, disable_on_timeout=True)
         else:
             super().__init__(timeout=None)
 
-        self.add_item(CategorySelect(options, bot, member, commands))
+        self.add_item(CategorySelect(options, bot, member, commands, interaction))

ezcord/internal/config.py

@@ -23,6 +23,7 @@ class EzConfig:
     BLACKLIST_COMMANDS = Literal["add", "remove", "show", "owner", "server", "show_servers"]
 
     lang: str = "en"
+    default_lang: str = "de"
     embed_templates: dict = {}
 
     # Blacklist

ezcord/internal/language/languages.py

@@ -4,11 +4,15 @@
 from pathlib import Path
 
 from ...logs import log
+from ..config import EzConfig
 
 
 @cache
 def load_lang(language: str) -> dict[str, dict[str, str]]:
-    """Loads the default language file and checks if the user provided a custom language file."""
+    """Loads the given language file and checks if the user provided a custom language file."""
+
+    if language == "auto":
+        language = EzConfig.default_lang
 
     lang = {}
     parent = Path(__file__).parent.absolute()
@@ -37,7 +41,7 @@ def load_lang(language: str) -> dict[str, dict[str, str]]:
                             lang[category] = {}
                         lang[category][value] = values[value]
 
-    if lang == {}:
+    if EzConfig.lang != "auto" and lang == {}:
         log.warn(f"Language file for language '{language}' not found. Falling back to 'en'.")
 
     return lang

ezcord/internal/translation.py

@@ -1,9 +1,11 @@
 """Internal language utilities for the library."""
 
+from __future__ import annotations
+
 import inspect
-from functools import cache
 from pathlib import Path
 
+from ..internal.dc import discord
 from ..logs import log
 from .config import EzConfig
 from .language.languages import load_lang
@@ -110,7 +112,9 @@ def plural_fr(amount: int, word: str) -> str:
     return word
 
 
-def tp(key: str, amount: int, *args: str, relative: bool = True) -> str:
+def tp(
+    key: str, amount: int, *args: str, relative: bool = True, i: discord.Interaction | None = None
+) -> str:
     """Load a string in the selected language and pluralize it.
 
     Parameters
@@ -123,9 +127,11 @@ def tp(key: str, amount: int, *args: str, relative: bool = True) -> str:
         The arguments to format the string with.
     relative:
         Whether to use relative time. Defaults to ``True``.
+    i:
+        The interaction to get the language from. Defaults to ``None``.
     """
-    word = t(key, *args)
-    lang = get_lang()
+    word = t(key, *args, i=i)
+    lang = EzConfig.lang
 
     if lang == "de":
         return plural_de(amount, word, relative)
@@ -137,7 +143,20 @@ def tp(key: str, amount: int, *args: str, relative: bool = True) -> str:
         return plural_en(amount, word)
 
 
-def t(key: str, *args: str):
+def get_locale(interaction: discord.Interaction | None) -> str:
+    if not interaction and EzConfig.lang == "auto":
+        return EzConfig.default_lang
+
+    if interaction and EzConfig.lang == "auto":
+        locale = interaction.guild_locale if interaction.guild_locale else interaction.locale
+        locale = locale.split("-")[0]
+    else:
+        locale = EzConfig.lang
+
+    return locale
+
+
+def t(key: str, *args: str, i: discord.Interaction | None = None) -> str:
     """Load a string in the selected language.
 
     Parameters
@@ -146,6 +165,8 @@ def t(key: str, *args: str):
         The text to load.
     *args:
         The arguments to format the string with.
+    i:
+        The interaction to get the language from. Defaults to ``None``.
     """
     n = 1
     origin_file = Path(inspect.stack()[n].filename).stem
@@ -154,32 +175,16 @@ def t(key: str, *args: str):
         n += 1
         origin_file = Path(inspect.stack()[n].filename).stem
 
-    lang = get_lang()
+    lang = EzConfig.lang
+    locale = get_locale(i)
 
     try:
-        string = load_lang(lang)[origin_file][key]
-        if not string:
-            return None
+        lang_dict = load_lang(locale)
+        string = lang_dict[origin_file][key]
         return string.format(*args)
     except KeyError:
         # fallback to english if the key is not in the custom language file
         # provided by the user
-        log.warn(f"Key '{key}' not found in language file '{lang}'. Falling back to 'en'.")
+        if lang != "auto":
+            log.warn(f"Key '{key}' not found in language file '{lang}'. Falling back to 'en'.")
         return load_lang("en")[origin_file][key].format(*args)
-
-
-@cache
-def get_lang():
-    """Get the language from the config class."""
-    return EzConfig.lang
-
-
-def set_lang(lang: str):
-    """Set the language for the bot.
-
-    Parameters
-    ----------
-    lang:
-        The language to set.
-    """
-    EzConfig.lang = lang