Add stubs for Windows

Relates-to: #929

voice/src/commonMain/kotlin/VoiceConnectionBuilder.kt

@@ -25,13 +25,23 @@ import kotlinx.coroutines.flow.first
 import kotlin.time.Duration
 import kotlin.time.Duration.Companion.milliseconds
 
+internal expect val isSupported: Boolean
+
 @KordVoice
 public class VoiceConnectionBuilder(
     public var gateway: Gateway,
     public var selfId: Snowflake,
     public var channelId: Snowflake,
     public var guildId: Snowflake
 ) {
+    init {
+        if(!isSupported) {
+            throw UnsupportedOperationException("""
+                Voice is currently not supported on Windows, if you're developing on Windows we recommend using
+                WSL: https://aka.ms/wsl
+            """.trimIndent())
+        }
+    }
     /**
      * The amount in milliseconds to wait for the events required to create a [VoiceConnection]. Default is 5000, or 5 seconds.
      */

voice/src/jsMain/kotlin/VoiceConnectionBuilder.js.kt

@@ -0,0 +1,3 @@
+package dev.kord.voice
+
+internal actual val isSupported: Boolean = true

voice/src/ktorMain/kotlin/VoiceConnectionBuilder.ktor.kt

@@ -0,0 +1,3 @@
+package dev.kord.voice
+
+internal actual val isSupported: Boolean = true

voice/src/ktorMain/kotlin/udp/VoiceUdpSocket.ktor.kt

@@ -0,0 +1,46 @@
+package dev.kord.voice.udp
+
+import dev.kord.common.annotation.KordVoice
+import dev.kord.voice.io.ByteArrayView
+import io.ktor.network.sockets.*
+import io.ktor.network.selector.*
+import io.ktor.network.sockets.Datagram
+import io.ktor.utils.io.core.*
+import kotlinx.coroutines.*
+import kotlinx.coroutines.flow.*
+import io.ktor.network.sockets.Datagram as KtorDatagram
+
+@KordVoice
+public actual typealias SocketAddress = InetSocketAddress
+
+@KordVoice
+public actual val GlobalVoiceUdpSocket: VoiceUdpSocket = object : VoiceUdpSocket {
+    private val socketScope =
+        CoroutineScope(Dispatchers.Default + SupervisorJob() + CoroutineName("kord-voice-global-socket"))
+
+    private val socket = aSocket(SelectorManager(socketScope.coroutineContext)).udp().bind()
+
+    private val incoming: MutableSharedFlow<Datagram> = MutableSharedFlow()
+
+    init {
+        socket.incoming
+            .consumeAsFlow()
+            .onEach { incoming.emit(it) }
+            .launchIn(socketScope)
+    }
+
+    override fun all(address: SocketAddress): Flow<ByteReadPacket> {
+        return incoming
+            .filter { it.address == address }
+            .map { it.packet }
+    }
+
+    override suspend fun send(address: SocketAddress, packet: ByteArrayView) {
+        val brp = ByteReadPacket(packet.data, packet.dataStart, packet.viewSize)
+        socket.send(KtorDatagram(brp, address))
+    }
+
+    override suspend fun stop() {
+    }
+}
+

voice/src/mingwMain/kotlin/VoiceConnectionBuilder.mingw.kt

@@ -0,0 +1,3 @@
+package dev.kord.voice
+
+internal actual val isSupported: Boolean = false

voice/src/mingwMain/kotlin/udp/VoiceUdpSocket.nonJs.kt

@@ -0,0 +1,18 @@
+package dev.kord.voice.udp
+
+import dev.kord.common.annotation.KordVoice
+import dev.kord.voice.io.ByteArrayView
+import io.ktor.utils.io.core.*
+import kotlinx.coroutines.flow.Flow
+
+@KordVoice
+public actual val GlobalVoiceUdpSocket: VoiceUdpSocket = object : VoiceUdpSocket {
+    override fun all(address: SocketAddress): Flow<ByteReadPacket> = unsupported()
+
+    override suspend fun send(address: SocketAddress, packet: ByteArrayView) = unsupported()
+
+    override suspend fun stop() = unsupported()
+}
+
+private fun unsupported(): Nothing = TODO("Voice is not supported on windows")
+

voice/src/nonKtorMain/kotlin/VoiceUdpSocket.js.kt

@@ -0,0 +1,9 @@
+package dev.kord.voice.udp
+
+import dev.kord.common.annotation.KordVoice
+
+@KordVoice
+public actual data class SocketAddress actual constructor(
+    public actual val hostname: String,
+    public actual val port: Int,
+)