Add group chat functions, slight refactoring

example.js

@@ -1,4 +1,4 @@
-const { Client } = require('./src')
+const { Client } = require('./index')
 
 const client = new Client({puppeteer: {headless: false}});
 
@@ -16,16 +16,60 @@ client.on('ready', () => {
     console.log('READY');
 });
 
-client.on('message', (msg) => {
+client.on('message', async msg => {
     console.log('MESSAGE RECEIVED', msg);
 
-    if (msg.body == 'ping reply') {
+    if (msg.body == '!ping reply') {
         // Send a new message as a reply to the current one
         msg.reply('pong');
 
-    } else if (msg.body == 'ping') {
+    } else if (msg.body == '!ping') {
         // Send a new message to the same chat
         client.sendMessage(msg.from, 'pong');
+
+    } else if (msg.body.startsWith('!subject ')) {
+        // Change the group subject
+        let chat = await msg.getChat();
+        if(chat.isGroup) {
+            let newSubject = msg.body.slice(9);
+            chat.setSubject(newSubject);
+        } else {
+            msg.reply('This command can only be used in a group!');
+        }
+    } else if (msg.body.startsWith('!echo ')) {
+        // Replies with the same message
+        msg.reply(msg.body.slice(6));
+    } else if (msg.body.startsWith('!desc ')) {
+        // Change the group description
+        let chat = await msg.getChat();
+        if(chat.isGroup) {
+            let newDescription = msg.body.slice(6);
+            chat.setDescription(newDescription);
+        } else {
+            msg.reply('This command can only be used in a group!');
+        }
+    } else if (msg.body == '!leave') {
+        // Leave the group
+        let chat = await msg.getChat();
+        if(chat.isGroup) {
+            chat.leave();
+        } else {
+            msg.reply('This command can only be used in a group!');
+        }
+    } else if(msg.body == '!groupinfo') {
+        let chat = await msg.getChat();
+        if(chat.isGroup) {
+            msg.reply(`
+                *Group Details*
+                Name: ${chat.name}
+                Description: ${chat.description}
+                Created At: ${chat.createdAt.toString()}
+                Created By: ${chat.owner.user}
+                Participant count: ${chat.participants.length}
+            `);
+        } else {
+            msg.reply('This command can only be used in a group!');
+        }
     }
 });