refactor: remove navigation orchestration from SendViewModel

app/src/main/java/com/bitcointxoko/gudariwallet/ui/WalletViewModel.kt

@@ -17,6 +17,7 @@ import com.bitcointxoko.gudariwallet.ui.balance.BalanceViewModel
 import com.bitcointxoko.gudariwallet.ui.clipboard.ClipboardViewModel
 import com.bitcointxoko.gudariwallet.ui.fiat.FiatViewModel
 import com.bitcointxoko.gudariwallet.ui.receive.ReceiveViewModel
+import com.bitcointxoko.gudariwallet.ui.send.SendEvent
 import com.bitcointxoko.gudariwallet.ui.send.SendStrings
 import com.bitcointxoko.gudariwallet.ui.send.SendViewModel
 import kotlinx.coroutines.flow.SharingStarted
@@ -110,6 +111,12 @@ class WalletViewModel(
     ) = sendVm.requestPayment(activity, subtitle, strings, pay)
     fun resetSendState() = sendVm.resetSendState()
 
+    val sendEvents: SharedFlow<SendEvent> = sendVm.events
+
+    fun handleWithdrawScanned(raw: LnurlScanResponse, lnurl: String) {
+        receiveVm.handleWithdrawResponse(raw, lnurl)
+    }
+
     val lightningAddress: StateFlow<String?> = lnAddressStore.lightningAddressFlow
         .stateIn(
             scope        = viewModelScope,

app/src/main/java/com/bitcointxoko/gudariwallet/ui/WalletViewModelFactory.kt

@@ -46,9 +46,6 @@ class WalletViewModelFactory(private val app: Application) : ViewModelProvider.F
             aliasRepo = aliasRepo,
             lnurlCache = lnurlCache,
             balanceVm = balanceVm,
-            onWithdrawScanned = { raw, lnurl ->
-                receiveVm.handleWithdrawResponse(raw, lnurl)
-            },
             scanner = lnurlScanner,
             payer   = lnurlPayer,
             poller     = poller,

app/src/main/java/com/bitcointxoko/gudariwallet/ui/send/SendScreen.kt

@@ -71,6 +71,15 @@ fun SendScreen(
         }
     }
 
+    LaunchedEffect(vm) {
+        vm.sendEvents.collect { event ->
+            when (event) {
+                is SendEvent.WithdrawScanned ->
+                    vm.handleWithdrawScanned(event.raw, event.lnurl)
+            }
+        }
+    }
+
     Column(
         modifier = Modifier
             .fillMaxSize()

app/src/main/java/com/bitcointxoko/gudariwallet/ui/send/SendViewModel.kt

@@ -21,12 +21,21 @@ import com.bitcointxoko.gudariwallet.util.SendInputType
 import com.bitcointxoko.gudariwallet.util.WalletConstants
 import com.bitcointxoko.gudariwallet.util.lnurlProtocolError
 import com.bitcointxoko.gudariwallet.util.parseApiError
+import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.launch
 
 private const val TAG = "SendViewModel"
 
+sealed class SendEvent {
+    data class WithdrawScanned(
+        val raw   : LnurlScanResponse,
+        val lnurl : String,
+    ) : SendEvent()
+}
+
 // ── String bundle injected at the call site ───────────────────────────────────
 /**
  * All user-visible strings produced by [SendViewModel].
@@ -53,11 +62,12 @@ class SendViewModel(
     private val aliasRepo  : NodeAliasRepository,
     private val lnurlCache : LnurlCacheRepository,
     private val balanceVm  : BalanceViewModel,
-    private val onWithdrawScanned: (raw: LnurlScanResponse, lnurl: String) -> Unit,
     private val scanner    : LnurlScanner,
     private val payer      : LnurlPayer,
     private val poller     : PaymentPoller,
 ) : ViewModel() {
+    private val _events = MutableSharedFlow<SendEvent>(extraBufferCapacity = 1)
+    val events: SharedFlow<SendEvent> = _events
 
     private val _sendState = MutableStateFlow<SendState>(SendState.Idle)
     val sendState: StateFlow<SendState> = _sendState
@@ -372,7 +382,7 @@ class SendViewModel(
                     when (raw.tag) {
                         "withdrawRequest" -> {
                             _sendState.value = SendState.Idle
-                            onWithdrawScanned(raw, httpsUrl)
+                            _events.tryEmit(SendEvent.WithdrawScanned(raw, httpsUrl))
                         }
                         "payRequest" -> {
                             lnurlCache.put(httpsUrl, raw)
@@ -464,7 +474,7 @@ class SendViewModel(
 
             when (raw.tag) {
                 "payRequest"      -> _sendState.value = buildLnurlReadyState(raw, normalized)
-                "withdrawRequest" -> { _sendState.value = SendState.Idle; onWithdrawScanned(raw, normalized) }
+                "withdrawRequest" -> { _sendState.value = SendState.Idle; _events.tryEmit(SendEvent.WithdrawScanned(raw, normalized)) }
                 null              -> _sendState.value = SendState.Error(strings.emptyResponse)
                 else              -> _sendState.value = SendState.Error(strings.unsupportedType(raw.tag))
             }