1 files changed, 60 insertions, 0 deletions
diff --git a/arthur/exts/error_handler/error_handler.py b/arthur/exts/error_handler/error_handler.py
new file mode 100644
index 0000000..2905fc3
--- /dev/null
+++ b/arthur/exts/error_handler/error_handler.py
@@ -0,0 +1,60 @@
+"""This cog provides error handling for King Arthur."""
+from discord import Message
+from arthur.utils import generate_error_embed
+from discord.ext import commands
+from discord.ext.commands import Cog
+
+from arthur.bot import KingArthur
+
+
+class ErrorHandler(Cog):
+    """Error handling for King Arthur."""
+
+    def __init__(self, bot: KingArthur) -> None:
+        self.bot = bot
+
+    async def _add_error_reaction(self, message: Message) -> None:
+        await message.add_reaction("\N{CROSS MARK}")
+
+    @Cog.listener()
+    async def on_command_error(self, ctx: commands.Context, error: commands.CommandError) -> None:
+        """Handle exceptions raised during command processing."""
+        if isinstance(error, commands.CommandNotFound):
+            return
+        if isinstance(error, commands.MissingRequiredArgument):
+            await self._add_error_reaction(ctx.message)
+            await ctx.send_help(ctx.command)
+        elif isinstance(error, commands.BadArgument):
+            await self._add_error_reaction(ctx.message)
+            await ctx.send_help(ctx.command)
+        elif isinstance(error, commands.CheckFailure):
+            await self._add_error_reaction(ctx.message)
+        elif isinstance(error, commands.NoPrivateMessage):
+            await self._add_error_reaction(ctx.message)
+        elif isinstance(error, commands.CommandOnCooldown):
+            await self._add_error_reaction(ctx.message)
+        elif isinstance(error, commands.DisabledCommand):
+            await self._add_error_reaction(ctx.message)
+        elif isinstance(error, commands.CommandInvokeError):
+            await self._add_error_reaction(ctx.message)
+            await ctx.send(
+                embed=generate_error_embed(
+                    description=(
+                        f"Command raised an error: `{error.original.__class__.__name__}:"
+                        f" {error.original}`"
+                    )
+                )
+            )
+        else:
+            await ctx.send(
+                embed=generate_error_embed(
+                    description=(
+                        f"Unknown exception occurred: `{error.__class__.__name__}:"
+                        f" {error}`"
+                    )
+                )
+            )
+
+def setup(bot: KingArthur) -> None:
+    """Add cog to bot."""
+    bot.add_cog(ErrorHandler(bot))