Made chromecast more robust. Improvements to IPv6 handling of casting devices.

app/src/main/java/com/futo/platformplayer/Utility.kt

@@ -31,6 +31,12 @@ import java.io.ByteArrayOutputStream
 import java.io.IOException
 import java.io.InputStream
 import java.io.OutputStream
+import java.net.Inet4Address
+import java.net.Inet6Address
+import java.net.InetAddress
+import java.net.InterfaceAddress
+import java.net.NetworkInterface
+import java.net.SocketException
 import java.nio.ByteBuffer
 import java.security.SecureRandom
 import java.time.OffsetDateTime
@@ -331,4 +337,98 @@ fun ByteArray.fromGzip(): ByteArray {
         }
     }
     return outputStream.toByteArray()
-}
+}
+
+fun findPreferredAddress(): InetAddress? {
+    val candidates = NetworkInterface.getNetworkInterfaces()
+        .toList()
+        .asSequence()
+        .filter(::isUsableInterface)
+        .flatMap { nif ->
+            nif.interfaceAddresses
+                .asSequence()
+                .mapNotNull { ia ->
+                    ia.address.takeIf(::isUsableAddress)?.let { addr ->
+                        nif to ia
+                    }
+                }
+        }
+        .toList()
+
+    return candidates
+        .minWithOrNull(
+            compareBy<Pair<NetworkInterface, InterfaceAddress>>(
+                { addressScore(it.second.address) },
+                { interfaceScore(it.first) },
+                { -it.second.networkPrefixLength.toInt() },
+                { -it.first.mtu }
+            )
+        )?.second?.address
+}
+
+private fun isUsableInterface(nif: NetworkInterface): Boolean {
+    val name = nif.name.lowercase()
+    return try {
+        // must be up, not loopback/virtual/PtP, have a MAC, not Docker/tun/etc.
+        nif.isUp
+            && !nif.isLoopback
+            && !nif.isPointToPoint
+            && !nif.isVirtual
+            && !name.startsWith("docker")
+            && !name.startsWith("veth")
+            && !name.startsWith("br-")
+            && !name.startsWith("virbr")
+            && !name.startsWith("vmnet")
+            && !name.startsWith("tun")
+            && !name.startsWith("tap")
+    } catch (e: SocketException) {
+        false
+    }
+}
+
+private fun isUsableAddress(addr: InetAddress): Boolean {
+    return when {
+        addr.isAnyLocalAddress -> false // 0.0.0.0 / ::
+        addr.isLoopbackAddress -> false
+        addr.isLinkLocalAddress -> false // 169.254.x.x or fe80::/10
+        addr.isMulticastAddress -> false
+        else -> true
+    }
+}
+
+private fun interfaceScore(nif: NetworkInterface): Int {
+    val name = nif.name.lowercase()
+    return when {
+        name.matches(Regex("^(eth|enp|eno|ens|em)\\d+")) -> 0
+        name.startsWith("eth") || name.contains("ethernet") -> 0
+        name.matches(Regex("^(wlan|wlp)\\d+")) -> 1
+        name.contains("wi-fi") || name.contains("wifi") -> 1
+        else -> 2
+    }
+}
+
+private fun addressScore(addr: InetAddress): Int {
+    return when (addr) {
+        is Inet4Address -> {
+            val octets = addr.address.map { it.toInt() and 0xFF }
+            when {
+                octets[0] == 10 -> 0  // 10/8
+                octets[0] == 192 && octets[1] == 168 -> 0  // 192.168/16
+                octets[0] == 172 && octets[1] in 16..31 -> 0  // 172.16–31/12
+                else -> 1  // public IPv4
+            }
+        }
+        is Inet6Address -> {
+            // ULA (fc00::/7) vs global vs others
+            val b0 = addr.address[0].toInt() and 0xFF
+            when {
+                (b0 and 0xFE) == 0xFC -> 2  // ULA
+                (b0 and 0xE0) == 0x20 -> 3  // global
+                else -> 4
+            }
+        }
+        else -> Int.MAX_VALUE
+    }
+}
+
+fun <T> Enumeration<T>.toList(): List<T> = Collections.list(this)

app/src/main/java/com/futo/platformplayer/casting/ChomecastCastingDevice.kt

@@ -10,7 +10,9 @@ import com.futo.platformplayer.toHexString
 import com.futo.platformplayer.toInetAddress
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.cancel
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
 import org.json.JSONObject
@@ -56,6 +58,10 @@ class ChromecastCastingDevice : CastingDevice {
     private var _mediaSessionId: Int? = null;
     private var _thread: Thread? = null;
     private var _pingThread: Thread? = null;
+    private var _launchRetries = 0
+    private val MAX_LAUNCH_RETRIES = 3
+    private var _lastLaunchTime_ms = 0L
+    private var _retryJob: Job? = null
 
     constructor(name: String, addresses: Array<InetAddress>, port: Int) : super() {
         this.name = name;
@@ -229,6 +235,7 @@ class ChromecastCastingDevice : CastingDevice {
         launchObject.put("appId", "CC1AD845");
         launchObject.put("requestId", _requestId++);
         sendChannelMessage("sender-0", "receiver-0", "urn:x-cast:com.google.cast.receiver", launchObject.toString());
+        _lastLaunchTime_ms = System.currentTimeMillis()
     }
 
     private fun getStatus() {
@@ -268,6 +275,7 @@ class ChromecastCastingDevice : CastingDevice {
             _contentType = null;
             _streamType = null;
             _sessionId = null;
+            _launchRetries = 0
             _transportId = null;
         }
 
@@ -282,6 +290,7 @@ class ChromecastCastingDevice : CastingDevice {
 
         _started = true;
         _sessionId = null;
+        _launchRetries = 0
         _mediaSessionId = null;
 
         Logger.i(TAG, "Starting...");
@@ -393,7 +402,7 @@ class ChromecastCastingDevice : CastingDevice {
                         try {
                             val inputStream = _inputStream ?: break;
 
-                            synchronized(_inputStreamLock)
+                            val message = synchronized(_inputStreamLock)
                             {
                                 Log.d(TAG, "Receiving next packet...");
                                 val b1 = inputStream.readUnsignedByte();
@@ -405,7 +414,7 @@ class ChromecastCastingDevice : CastingDevice {
                                 if (size > buffer.size) {
                                     Logger.w(TAG, "Skipping packet that is too large $size bytes.")
                                     inputStream.skip(size.toLong());
-                                    return@synchronized
+                                    return@synchronized null
                                 }
 
                                 Log.d(TAG, "Received header indicating $size bytes. Waiting for message.");
@@ -414,15 +423,19 @@ class ChromecastCastingDevice : CastingDevice {
                                 //TODO: In the future perhaps this size-1 will cause issues, why is there a 0 on the end?
                                 val messageBytes = buffer.sliceArray(IntRange(0, size - 1));
                                 Log.d(TAG, "Received $size bytes: ${messageBytes.toHexString()}.");
-                                val message = ChromeCast.CastMessage.parseFrom(messageBytes);
+                                val msg = ChromeCast.CastMessage.parseFrom(messageBytes);
-                                if (message.namespace != "urn:x-cast:com.google.cast.tp.heartbeat") {
+                                if (msg.namespace != "urn:x-cast:com.google.cast.tp.heartbeat") {
-                                    Logger.i(TAG, "Received message: $message");
+                                    Logger.i(TAG, "Received message: $msg");
                                 }
+                                return@synchronized msg
+                            }
 
+                            if (message != null) {
                                 try {
                                     handleMessage(message);
                                 } catch (e: Throwable) {
                                     Logger.w(TAG, "Failed to handle message.", e);
+                                    break
                                 }
                             }
                         } catch (e: java.net.SocketException) {
@@ -512,6 +525,7 @@ class ChromecastCastingDevice : CastingDevice {
                             if (_sessionId == null) {
                                 connectionState = CastConnectionState.CONNECTED;
                                 _sessionId = applicationUpdate.getString("sessionId");
+                                _launchRetries = 0
 
                                 val transportId = applicationUpdate.getString("transportId");
                                 connectMediaChannel(transportId);
@@ -526,21 +540,40 @@ class ChromecastCastingDevice : CastingDevice {
                 }
 
                 if (!sessionIsRunning) {
-                    _sessionId = null;
+                    if (System.currentTimeMillis() - _lastLaunchTime_ms > 5000) {
-                    _mediaSessionId = null;
+                        _sessionId = null
-                    setTime(0.0);
+                        _mediaSessionId = null
-                    _transportId = null;
+                        setTime(0.0)
-                    Logger.w(TAG, "Session not found.");
+                        _transportId = null
 
-                    if (_launching) {
+                        if (_launching && _launchRetries < MAX_LAUNCH_RETRIES) {
-                        Logger.i(TAG, "Player not found, launching.");
+                            Logger.i(TAG, "No player yet; attempting launch #${_launchRetries + 1}")
-                        launchPlayer();
+                            _launchRetries++
+                            launchPlayer()
+                        } else if (!_launching && _launchRetries < MAX_LAUNCH_RETRIES) {
+                            // Maybe the first GET_STATUS came back empty; still try launching
+                            Logger.i(TAG, "Player not found; triggering launch #${_launchRetries + 1}")
+                            _launching = true
+                            _launchRetries++
+                            launchPlayer()
+                        } else {
+                            Logger.e(TAG, "Player not found after $_launchRetries attempts; giving up.")
+                            Logger.i(TAG, "Unable to start media receiver on device")
+                            stop()
+                        }
                     } else {
-                        Logger.i(TAG, "Player not found, disconnecting."); //TODO: Add recovery from this scenario ?
+                        if (_retryJob == null) {
-                        stop();
+                            Logger.i(TAG, "Scheduled retry job over 5 seconds")
+                            _retryJob = _scopeIO?.launch(Dispatchers.IO) {
+                                delay(5000)
+                                getStatus()
+                                _retryJob = null
+                            }
+                        }
                     }
                 } else {
-                    _launching = false;
+                    _launching = false
+                    _launchRetries = 0
                 }
 
                 val volume = status.getJSONObject("volume");
@@ -582,6 +615,8 @@ class ChromecastCastingDevice : CastingDevice {
                 if (message.sourceId == "receiver-0") {
                     Logger.i(TAG, "Close received.");
                     stop();
+                } else if (_transportId == message.sourceId) {
+                    throw Exception("Transport id closed.")
                 }
             }
         } else {
@@ -616,6 +651,9 @@ class ChromecastCastingDevice : CastingDevice {
         localAddress = null;
         _started = false;
 
+        _retryJob?.cancel()
+        _retryJob = null
+
         val socket = _socket;
         val scopeIO = _scopeIO;
 

app/src/main/java/com/futo/platformplayer/casting/StateCasting.kt

@@ -43,6 +43,7 @@ import com.futo.platformplayer.builders.DashBuilder
 import com.futo.platformplayer.constructs.Event1
 import com.futo.platformplayer.constructs.Event2
 import com.futo.platformplayer.exceptions.UnsupportedCastException
+import com.futo.platformplayer.findPreferredAddress
 import com.futo.platformplayer.logging.Logger
 import com.futo.platformplayer.models.CastingDeviceInfo
 import com.futo.platformplayer.parsers.HLS
@@ -61,6 +62,7 @@ import java.net.Inet6Address
 import java.net.InetAddress
 import java.net.URLDecoder
 import java.net.URLEncoder
+import java.util.Collections
 import java.util.UUID
 
 class StateCasting {
@@ -1216,26 +1218,13 @@ class StateCasting {
         }
     }
 
-    private fun findFirstIPv4(): InetAddress? {
-        val interfaces = NetworkInterface.getNetworkInterfaces()
-        for (intf in interfaces) {
-            if (!intf.isUp || intf.isLoopback) continue
-            for (addr in intf.inetAddresses) {
-                if (addr is Inet4Address && !addr.isLoopbackAddress) {
-                    return addr
-                }
-            }
-        }
-        return null
-    }
-
     private fun getLocalUrl(ad: CastingDevice): String {
         var address = ad.localAddress!!
         if (address is Inet6Address && address.isLinkLocalAddress) {
-            address = findFirstIPv4() ?: address
+            address = findPreferredAddress() ?: address
             Logger.i(TAG, "Selected casting address: $address")
         }
-        return "http://${ad.localAddress.toUrlAddress().trim('/')}:${_castServer.port}";
+        return "http://${address.toUrlAddress().trim('/')}:${_castServer.port}";
     }
 
     @OptIn(UnstableApi::class)