feat: add registerable events

src/bot.ts

@@ -1,12 +1,23 @@
 import {
+    CacheType,
     Client,
     GatewayIntentBits,
+    Interaction,
+    Message,
     OAuth2Scopes,
-	PermissionFlagsBits
+    PermissionFlagsBits,
+    VoiceState
 } from 'discord.js';
 import { Logger } from './utils/log';
 import { config } from './utils/config';
 
+type BotEventListeners = {
+    'messageCreate': (message: Message) => void;
+    'interactionCreate': (interaction: Interaction) => void;
+    'voiceStateUpdate': (oldState: VoiceState, newState: VoiceState) => void;
+};
+type BotEventListener<K extends keyof BotEventListeners> = BotEventListeners[K];
+
 export class Bot {
     private client: Client | undefined;
 
@@ -15,6 +26,66 @@ export class Bot {
 
     private readonly log: Logger;
 
+    private eventListeners: {
+        [K in keyof BotEventListeners]?: BotEventListener<K>[];
+    } = {};
+
+    /*
+        event methods
+    */
+     public on<K extends keyof BotEventListeners>(
+        event: K, 
+        listener: BotEventListener<K>
+    ): void {
+        if (!this.eventListeners[event]) {
+            this.eventListeners[event] = [];
+        }
+        (this.eventListeners[event] as BotEventListener<K>[]).push(listener);
+    }
+
+    public off<K extends keyof BotEventListeners>(
+        event: K, 
+        listener: BotEventListener<K>
+    ): boolean {
+        const listeners = this.eventListeners[event];
+        if (!listeners) return false;
+
+        const index = (listeners as BotEventListener<K>[]).indexOf(listener);
+        if (index > -1) {
+            (listeners as BotEventListener<K>[]).splice(index, 1);
+            return true;
+        }
+        return false;
+    }
+
+    public once<K extends keyof BotEventListeners>(
+        event: K, 
+        listener: BotEventListener<K>
+    ): void {
+        const onceWrapper = ((...args: Parameters<BotEventListener<K>>) => {
+            this.off(event, onceWrapper as BotEventListener<K>);
+            (listener as (...args: unknown[]) => void)(...args);
+        }) as BotEventListener<K>;
+        
+        this.on(event, onceWrapper);
+    }
+
+    private emit<K extends keyof BotEventListeners>(
+        event: K, 
+        ...args: Parameters<BotEventListener<K>>
+    ): void {
+        const listeners = this.eventListeners[event];
+        if (listeners) {
+            for (const listener of listeners as BotEventListener<K>[]) {
+                try {
+                    (listener as (...args: unknown[]) => void)(...args);
+                } catch (error) {
+                    this.log.error(`Error in event listener for ${String(event)}:`, error);
+                }
+            }
+        }
+    }
+
     /*
         class methods
     */
@@ -45,6 +116,9 @@ export class Bot {
         this.client.on('clientReady', () => this.onReady());
         this.client.on('error', (err) => this.onError(err, false));
         this.client.on('shardError', (err) => this.onError(err, true));
+        this.client.on('messageCreate', (message: Message<boolean>) => this.onMessage(message));
+        this.client.on('interactionCreate', (interaction: Interaction<CacheType>) => this.onInteraction(interaction));
+        this.client.on('voiceStateUpdate', (oldState: VoiceState, newState: VoiceState) => this.onVoiceStateUpdate(oldState, newState));
 
         this.log.info('Logging in...');
         await this.client.login(this.token);
@@ -93,6 +167,21 @@ export class Bot {
             );
     }
 
+    /*
+        public event listeners
+    */
+    private async onInteraction(interaction: Interaction): Promise<void> {
+        this.emit('interactionCreate', interaction);
+    }
+
+    private async onMessage(message: Message): Promise<void> {
+        this.emit('messageCreate', message);
+    }
+
+    private async onVoiceStateUpdate(oldState: VoiceState, newState: VoiceState): Promise<void> {
+        this.emit('voiceStateUpdate', oldState, newState);
+    }
+
     /*
         singleton logic
     */