basic disconnect handling, log4j-slf4j-impl, readme update.

Author: Mark Nefedov

README.md

@@ -1,11 +1,16 @@
 # Simple Discord bot in Kotlin
 A simple bot for recording voice chats.
 
-Usage:
+For simple recording:
 ```
 ::record time
 ::stop
 ```
+"Instant replay" functions much like Nvidia's ShadowPlay instant replays (that is where name come from). Bot is constantly recording audio from a channel to a buffer and will send current buffer content in a file when you request it.
+```
+:!record 
+:!replay
+```
 
 After recording bot will send an audio file to the chat it was started from.
 

build.gradle

@@ -14,6 +14,7 @@ dependencies {
     compile "net.dv8tion:JDA:4.1.1_101"
     compile group: 'ws.schild', name: 'jave-all-deps', version: '2.7.3'
     compile group: 'org.apache.commons', name: 'commons-collections4', version: '4.4'
+    compile group: 'org.apache.logging.log4j', name: 'log4j-slf4j-impl', version: '2.13.1'
 }
 
 compileKotlin {

src/main/kotlin/InstantReplayCommandHandler.kt

@@ -1,5 +1,6 @@
 import net.dv8tion.jda.api.audio.AudioReceiveHandler
 import net.dv8tion.jda.api.audio.CombinedAudio
+import net.dv8tion.jda.api.events.guild.voice.GuildVoiceLeaveEvent
 import net.dv8tion.jda.api.events.message.guild.GuildMessageReceivedEvent
 import net.dv8tion.jda.api.hooks.ListenerAdapter
 import org.apache.commons.collections4.queue.CircularFifoQueue
@@ -28,6 +29,15 @@ class InstantReplayCommandHandler : ListenerAdapter() {
             event.message.textChannel.sendFile(mp3Compressed).submit().thenRunAsync { mp3Compressed.delete() }
         }
     }
+
+    override fun onGuildVoiceLeave(event: GuildVoiceLeaveEvent) {
+        super.onGuildVoiceLeave(event)
+        if (event.member.id == clientId)
+        {
+            println("Bot leave from: ${event.channelLeft.name}")
+            event.guild.audioManager.receivingHandler = null
+        }
+    }
 }
 
 class InstantReplayAudioHandler : AudioReceiveHandler {

src/main/kotlin/main.kt

@@ -1,19 +1,33 @@
 import net.dv8tion.jda.api.JDABuilder
 
+lateinit var clientId : String
+
 fun main(args : Array<String>) {
     val token = when {
         args.isNotEmpty() -> args[0]
         System.getenv("BOT_TOKEN") != null -> System.getenv("BOT_TOKEN")
         else -> {
-            print("Bot token:")
+            println("Bot token:")
             (readLine() ?: return)
         }
     }
+
+    clientId = when {
+        args.size > 1 -> args[1]
+        System.getenv("CLIENT_ID") != null -> System.getenv("CLIENT_ID")
+        else -> {
+            println("Client id: ")
+            (readLine() ?: return)
+        }
+    }
+
+    println("Starting bot")
     JDABuilder(token).apply {
         addEventListeners(
             RecordCommandHandler(),
             InstantReplayCommandHandler()
         )
+        setAutoReconnect(true)
         build()
     }
 }