feat: (for now android only!) codec configuration and retrieval methods

android/src/main/kotlin/xyz/nuark/liblinphone_flutter/LiblinphoneFlutterPlugin.kt

@@ -263,6 +263,21 @@ class LiblinphoneFlutterPlugin : FlutterPlugin, ActivityAware, MethodCallHandler
                 result.success(linphoneBridge.getCurrentCallStats()?.toMap())
             }
 
+            "getAvailableAudioCodecs" -> {
+                result.success(linphoneBridge.getAvailableAudioCodecs())
+            }
+
+            "setAudioCodec" -> {
+                try {
+                    val mime = call.argument<String>("mime")!!
+                    val clockRate = call.argument<Int>("clockRate")!!
+                    result.success(linphoneBridge.setAudioCodec(mime, clockRate))
+                } catch (e: Exception) {
+                    Log.e(TAG, "setAudioCodec: ${e.message}")
+                    result.error("error", e.message, e)
+                }
+            }
+
             else -> {
                 result.notImplemented()
             }

android/src/main/kotlin/xyz/nuark/liblinphone_flutter/LinphoneBridge.kt

@@ -549,4 +549,61 @@ class LinphoneBridge(
             isZrtpKeyAgreementAlgoPostQuantum = stats.isZrtpKeyAgreementAlgoPostQuantum(),
         )
     }
+
+    data class LPCodec(
+        val mimeType: String,
+        val clockRate: Int,
+        val enabled: Boolean,
+    ) {
+        fun toMap(): Map<String, Any?> {
+            return mapOf(
+                "mimeType" to mimeType,
+                "clockRate" to clockRate,
+                "enabled" to enabled,
+            );
+        }
+    }
+
+    fun getAvailableAudioCodecs(): List<Map<String, Any?>> {
+        return core.audioPayloadTypes.map {
+            LPCodec(
+                mimeType = it.mimeType.lowercase(), 
+                clockRate = it.clockRate, 
+                enabled = it.enabled()
+            ).toMap()
+        }
+    }
+
+    fun setAudioCodec(mime: String, clockRate: Int): Boolean {
+        var codecFound = false
+        var ok = false
+        core.audioPayloadTypes.forEach { pt: PayloadType ->
+            val ptMime = pt.mimeType.lowercase()
+            val ptClockRate = pt.clockRate
+            val enable = ptMime == mime && ptClockRate == clockRate
+            if (enable) {
+                ok = pt.enable(enable) == 0
+                codecFound = true
+                Log.i(
+                    LiblinphoneFlutterPlugin.TAG,
+                    "setAudioCodec: preferred codec found ($ptMime @ $clockRate) switch: $ok"
+                )
+            } else {
+                val switchedOk = pt.enable(enable) == 0
+                Log.i(
+                    LiblinphoneFlutterPlugin.TAG,
+                    "setAudioCodec: $ptMime @ $clockRate switch: $switchedOk"
+                )
+            }
+        }
+
+        if (!codecFound) {
+            Log.i(
+                LiblinphoneFlutterPlugin.TAG,
+                "setAudioCodec: could not find codec with parans $mime @ $clockRate"
+            )
+        }
+
+        return ok
+    }
 }