Events cog; currently handles command errors

2 files changed, 51 insertions, 0 deletions

diff --git a/bot/__main__.py b/bot/__main__.py
index b0cdbe803..32686a27a 100644
--- a/bot/__main__.py
+++ b/bot/__main__.py
@@ -8,6 +8,7 @@ bot = AutoShardedBot(command_prefix=when_mentioned_or(">>> ", ">>>"))
 # Internal/debug
 bot.load_extension("bot.cogs.logging")
 bot.load_extension("bot.cogs.security")
+bot.load_extension("bot.cogs.events")
 
 # Owner-only
 bot.load_extension("bot.cogs.eval")
diff --git a/bot/cogs/events.py b/bot/cogs/events.py
new file mode 100644
index 000000000..35f09d913
--- /dev/null
+++ b/bot/cogs/events.py
@@ -0,0 +1,50 @@
+# coding=utf-8
+from discord import Guild
+from discord.ext.commands import (
+    AutoShardedBot, CommandError, Context, BadArgument, NoPrivateMessage,
+    CommandInvokeError, UserInputError, BotMissingPermissions
+)
+
+__author__ = "Gareth Coles"
+
+
+class Events:
+    """
+    No commands, just event handlers
+    """
+
+    def __init__(self, bot: AutoShardedBot):
+        self.bot = bot
+
+    async def on_command_error(self, ctx: Context, e: CommandError):
+        command = ctx.command
+        parent = command.parent
+
+        if parent:
+            help_command = (self.bot.get_command("help"), parent.name, command.name)
+        else:
+            help_command = (self.bot.get_command("help"), command.name)
+
+        if isinstance(e, BadArgument):
+            await ctx.send(f"Bad argument: {e}\n")
+            await ctx.invoke(*help_command)
+        elif isinstance(e, UserInputError):
+            await ctx.invoke(*help_command)
+        elif isinstance(e, NoPrivateMessage):
+            await ctx.send("Sorry, this command can't be used in a private message!")
+        elif isinstance(e, BotMissingPermissions):
+            await ctx.send(
+                f"Sorry, it looks like I don't have the permissions I need to do that.\n\n"
+                f"Here's what I'm missing: **{e.missing_perms}**"
+            )
+        elif isinstance(e, CommandInvokeError):
+            await ctx.send(
+                f"Sorry, an unexpected error occurred. Please let us know!\n\n```{e}```"
+            )
+            raise e.original
+        print(e)
+
+
+def setup(bot):
+    bot.add_cog(Events(bot))
+    print("Cog loaded: Events")