Move to better solution for gateway discovery

common/src/main/kotlin/org/muellerssoftware/openproximitychat/common/Logging.kt

@@ -1,53 +1,65 @@
+@file:OptIn(DelicateCoroutinesApi::class)
 package org.muellerssoftware.openproximitychat.common
 
-import org.slf4j.Logger
+import org.bitlet.weupnp.GatewayDevice
+import org.bitlet.weupnp.GatewayDiscover
+import kotlinx.coroutines.*
 
-object Logging {
-    enum class LogType {
-        Debug,
-        Info,
-        Error
-    }
+object UPnPManager {
+    var gateway: GatewayDevice? = null
+    val mappedPorts = mutableMapOf<Int, Int>()
+    var discoveryJob: Job = Job()
 
-    var logger: Logger? = null
-        set(value) {
-            for (log in backLog) {
-                when (log.first) {
-                    LogType.Debug -> value?.debug(log.second)
-                    LogType.Info -> value?.info(log.second)
-                    LogType.Error -> value?.error(log.second)
-                }
+    init {
+        runBlocking {
+            discoveryJob = GlobalScope.launch {
+                startGatewayDiscover()
             }
-
-            field = value
-        }
-
-    var backLog = mutableListOf<Pair<LogType, String>>()
-
-    fun info(message: String) {
-        if (logger != null) {
-            logger!!.info(message)
-        }
-        else {
-            backLog.add(Pair(LogType.Info, message))
         }
     }
 
-    fun error(message: String) {
-        if (logger != null) {
-            logger!!.error(message)
+    suspend fun startGatewayDiscover() {
+        val gatewayDiscoverer = GatewayDiscover()
+        for (i in 0..9) {
+            Logging.info("Searching for UPnP gateway... (Attempt ${i + 1})")
+            gatewayDiscoverer.discover()
+            if (gatewayDiscoverer.getValidGateway() != null) {
+                gateway = gatewayDiscoverer.validGateway
+                break
+            }
+        }
+
+        if (gateway == null) {
+            Logging.error("No UPnP gateway found!")
         }
         else {
-            backLog.add(Pair(LogType.Error, message))
+            Logging.info("UPnP gateway found: ${gateway!!.friendlyName}")
+            val ports = mappedPorts.toMutableMap()
+            mappedPorts.clear()
+            ports.map {
+                mapPort(it.key, it.value)
+            }
         }
     }
 
-    fun debug(message: String) {
-        if (logger != null) {
-            logger!!.debug(message)
+    fun mapPort(port: Int) {
+        mapPort(port, port)
+    }
+
+    fun mapPort(internalPort: Int, externalPort: Int) {
+        if (gateway == null) {
+            mappedPorts.put(internalPort, externalPort)
         }
-        else {
-            backLog.add(Pair(LogType.Debug, message))
+
+        val succeeded = gateway?.addPortMapping(externalPort, internalPort, gateway!!.localAddress.hostAddress, "UDP", "OpenProximityChat mapped port")
+        if (succeeded == true) {
+            mappedPorts.put(internalPort, externalPort)
+        }
+    }
+
+    fun unMapAll() {
+        mappedPorts.map {
+            gateway?.deletePortMapping(it.value, "UDP")
         }
     }
 }