Load mixminus module on-demand and add calls to conference dynamically

app/src/main/kotlin/com/tutpro/baresip/BaresipService.kt

@@ -1104,6 +1104,8 @@ class BaresipService: Service() {
                                 call.onHoldCall = null
                             }
                             call.remove()
+                            if (call.conferenceCall && ua.calls().isEmpty())
+                                Api.module_unload("mixminus")
                             val reason = ev[1]
                             val tone = ev[2]
                             if (tone == "busy") {

app/src/main/kotlin/com/tutpro/baresip/Call.kt

@@ -11,6 +11,7 @@ class Call(val callp: Long, val ua: UserAgent, val peerUri: String, val dir: Str
 
     var onhold = false
     var held = false
+    var terminated = false
     var conferenceCall = false
     var onHoldCall: Call? = null
     var newCall: Call? = null

app/src/main/kotlin/com/tutpro/baresip/MainScreen.kt

@@ -1478,10 +1478,13 @@ private fun CallRow(
                 IconButton(
                     modifier = Modifier.size(48.dp),
                     onClick = {
+                        if (!call.terminated) {
+                            call.terminated = true
                             abandonAudioFocus(ctx)
                             Log.d(TAG, "AoR ${call.ua.account.aor} hanging up call ${call.callp} with ${call.callUri.value}")
                             Api.ua_hangup(call.ua.uap, call.callp, 487, "Request Terminated")
                         }
+                    }
                 ) {
                     Icon(
                         imageVector = Icons.Filled.CallEnd,
@@ -2067,6 +2070,8 @@ private fun call(
     onHoldCall: Call? = null
 ): Call? {
     spinToAor(viewModel, ua.account.aor)
+    if (conferenceCall && ua.calls().isEmpty())
+        Api.module_load("mixminus")
     val callp = ua.callAlloc(0L, Api.VIDMODE_OFF)
     return if (callp != 0L) {
         Log.d(TAG, "Adding outgoing call ${ua.uap}/$callp/$uri")
@@ -2090,6 +2095,8 @@ private fun call(
         }
     } else {
         Log.w(TAG, "callAlloc for ${ua.uap} to $uri failed")
+        if (conferenceCall && ua.calls().isEmpty())
+            Api.module_unload("mixminus")
         null
     }
 }
@@ -2318,6 +2325,8 @@ fun handleServiceEvent(ctx: Context, viewModel: ViewModel, event: String, params
                 val call = Call.ofCallp(callp)
                 if (call != null) {
                     call.dtmfText.value = ""
+                    if (call.conferenceCall)
+                        Api.cmd_exec("conference")
                 }
                 showCall(ctx, viewModel, ua, call)
             }