feat: implement structured logging system for commands and errors (#30)

bot.py

@@ -19,12 +19,9 @@
 # Load environment variables
 load_dotenv()
 
-# Configure logging
-logging.basicConfig(
-    level=getattr(logging, os.getenv("LOG_LEVEL", "INFO")),
-    format="%(asctime)s - %(name)s - %(levelname)s - %(message)s",
-    handlers=[logging.FileHandler("bot.log"), logging.StreamHandler()],
-)
+from utils.logger import setup_logging
+
+setup_logging()
 logger = logging.getLogger(__name__)
 
 
@@ -65,7 +62,8 @@ def __init__(self, config: Config):
 
     async def setup_hook(self) -> None:
         """Setup hook called before the bot starts."""
-        # Initialize CodeBuddy database
+        self.tree.on_app_command_completion = self.on_app_command_completion
+
         try:
             from utils.codebuddy_database import init_db
 
@@ -176,6 +174,18 @@ async def on_ready(self):
             activity=discord.Game(name="?helpmenu /help | Made by YC45")
         )
 
+    async def on_command_completion(self, ctx: commands.Context):
+        """Handle prefix command completion."""
+        from utils.logger import log_command_usage
+        log_command_usage(ctx, command_type="PREFIX", success=True)
+
+    async def on_app_command_completion(
+        self, interaction: discord.Interaction, command: app_commands.Command
+    ):
+        """Handle slash command completion."""
+        from utils.logger import log_command_usage
+        log_command_usage(interaction, command_type="SLASH", success=True)
+
     async def on_command_error(
         self, ctx: commands.Context, error: commands.CommandError
     ):
@@ -184,6 +194,9 @@ async def on_command_error(
         if isinstance(error, commands.CommandNotFound):
             return
 
+        from utils.logger import log_command_usage
+        log_command_usage(ctx, command_type="PREFIX", success=False, error=error)
+
         async def _safe_ctx_send(message: str) -> None:
             """Send a message without crashing on expired slash interactions.
 
@@ -235,6 +248,9 @@ async def on_app_command_error(
         self, interaction: discord.Interaction, error: app_commands.AppCommandError
     ):
         """Handle slash command errors."""
+        from utils.logger import log_command_usage
+        log_command_usage(interaction, command_type="SLASH", success=False, error=error)
+
         # Silence unknown slash/app commands.
         # `app_commands` doesn't expose a stable CommandNotFound across versions, so be conservative.
 

utils/logger.py

@@ -0,0 +1,61 @@
+import logging
+import os
+import discord
+from discord.ext import commands
+
+logger = logging.getLogger("EigenBot")
+
+def setup_logging():
+    log_level_str = os.getenv("LOG_LEVEL", "INFO")
+    log_level = getattr(logging, log_level_str.upper(), logging.INFO)
+
+    os.makedirs("logs", exist_ok=True)
+    file_handler = logging.FileHandler(os.path.join("logs", "bot.log"), encoding="utf-8")
+    stream_handler = logging.StreamHandler()
+
+    formatter = logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+    file_handler.setFormatter(formatter)
+    stream_handler.setFormatter(formatter)
+
+    root_logger = logging.getLogger()
+    root_logger.setLevel(log_level)
+    root_logger.handlers.clear()
+    root_logger.addHandler(file_handler)
+    root_logger.addHandler(stream_handler)
+
+    logger.info("Logging system configured successfully.")
+
+def log_command_usage(ctx_or_interaction, command_type: str, success: bool, error: Exception = None):
+    """Formats and logs command usage consistently."""
+    try:
+        if isinstance(ctx_or_interaction, commands.Context):
+            user_id = ctx_or_interaction.author.id
+            username = ctx_or_interaction.author.name
+            if ctx_or_interaction.command:
+                command_name = ctx_or_interaction.command.qualified_name
+            else:
+                command_name = "Unknown"
+        elif isinstance(ctx_or_interaction, discord.Interaction):
+            user_id = ctx_or_interaction.user.id
+            username = ctx_or_interaction.user.name
+            if ctx_or_interaction.command:
+                command_name = ctx_or_interaction.command.qualified_name
+            elif ctx_or_interaction.data:
+                command_name = ctx_or_interaction.data.get("name", "Unknown")
+            else:
+                command_name = "Unknown"
+        else:
+            return
+
+        status = "SUCCESS" if success else f"FAILED ({type(error).__name__}: {error})"
+        message = (
+            f"[{command_type}] User: {username} ({user_id}) | "
+            f"Command: {command_name} | Status: {status}"
+        )
+
+        if success:
+            logger.info(message)
+        else:
+            logger.error(message)
+    except Exception as log_err:
+        logger.error(f"Failed to write command log: {log_err}")