demo: initial send functionality on wallet screen

demo/android/src/main/kotlin/im/molly/monero/demo/data/WalletRepository.kt

@@ -63,6 +63,10 @@ class WalletRepository(
     fun getTransaction(walletId: Long, txId: String): Flow<Transaction?> =
         getLedger(walletId).map { it.transactionById[txId] }
 
+    suspend fun createTransfer(walletId: Long, transferRequest: TransferRequest): PendingTransfer {
+        return getWallet(walletId).createTransfer(transferRequest)
+    }
+
     suspend fun addWallet(
         moneroNetwork: MoneroNetwork,
         name: String,

demo/android/src/main/kotlin/im/molly/monero/demo/ui/AddWalletWizard.kt

@@ -170,10 +170,10 @@ private fun SecondStepScreen(
             )
             SelectListBox(
                 label = "Network",
-                options = MoneroNetwork.values().map { it.name },
+                options = MoneroNetwork.entries.associateWith { it.name },
-                selectedOption = network.name,
+                selectedOption = network,
                 onOptionClick = {
-                    onNetworkChanged(MoneroNetwork.valueOf(it))
+                    onNetworkChanged(it)
                 },
                 modifier = Modifier
                     .fillMaxWidth()

demo/android/src/main/kotlin/im/molly/monero/demo/ui/AddressCard.kt

@@ -7,14 +7,11 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
-import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.alpha
 import androidx.compose.ui.unit.dp
 import im.molly.monero.demo.data.model.WalletAddress
 import im.molly.monero.demo.ui.component.CopyableText
-import im.molly.monero.demo.ui.theme.Blue40
-import im.molly.monero.demo.ui.theme.Red40
 
 @Composable
 fun AddressCardExpanded(
@@ -47,10 +44,6 @@ fun AddressCardExpanded(
                 modifier = if (used) Modifier.alpha(0.5f) else Modifier,
             )
             if (walletAddress.isLastForAccount) {
-                Column(
-                    modifier = Modifier.fillMaxWidth(),
-                    horizontalAlignment = Alignment.CenterHorizontally,
-                ) {
                 TextButton(onClick = onCreateSubAddressClick) {
                     Text(
                         text = "Add subaddress",
@@ -58,7 +51,7 @@ fun AddressCardExpanded(
                     )
                 }
             }
-            }
+
         }
     }
 }

demo/android/src/main/kotlin/im/molly/monero/demo/ui/EditRemoteNodeDialog.kt

@@ -67,10 +67,10 @@ private fun EditRemoteNodeDialog(
                 )
                 SelectListBox(
                     label = "Network",
-                    options = MoneroNetwork.values().map { it.name },
+                    options = MoneroNetwork.entries.associateWith { it.name },
-                    selectedOption = remoteNode.network.name,
+                    selectedOption = remoteNode.network,
                     onOptionClick = {
-                        onRemoteNodeChange(remoteNode.copy(network = MoneroNetwork.valueOf(it)))
+                        onRemoteNodeChange(remoteNode.copy(network = it))
                     }
                 )
                 Column {

demo/android/src/main/kotlin/im/molly/monero/demo/ui/RecipientList.kt

@@ -0,0 +1,123 @@
+package im.molly.monero.demo.ui
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import im.molly.monero.MoneroCurrency
+
+@Composable
+fun EditableRecipientList(
+    recipients: List<Pair<String, String>>,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    onRecipientChange: (List<Pair<String, String>>) -> Unit = {},
+) {
+    val updatedList = recipients.toMutableList()
+
+    if (updatedList.isEmpty()) {
+        updatedList.add("" to "")
+        onRecipientChange(updatedList)
+    }
+
+    Column(modifier = modifier) {
+        updatedList.forEachIndexed { index, (address, amount) ->
+            PaymentDetailItem(
+                itemIndex = index,
+                amount = amount,
+                address = address,
+                enabled = enabled,
+                onAmountChange = {
+                    updatedList[index] = address to it
+                    onRecipientChange(updatedList)
+                },
+                onAddressChange = {
+                    updatedList[index] = it to amount
+                    onRecipientChange(updatedList)
+                },
+                onDeleteItemClick = {
+                    updatedList.removeAt(index)
+                    onRecipientChange(updatedList)
+                }
+            )
+        }
+        TextButton(
+            onClick = { onRecipientChange(updatedList + ("" to "")) },
+            enabled = enabled,
+            modifier = Modifier.padding(bottom = 8.dp),
+        ) {
+            Text(text = "Add recipient")
+        }
+    }
+}
+
+@Composable
+fun PaymentDetailItem(
+    itemIndex: Int,
+    address: String,
+    amount: String,
+    enabled: Boolean = true,
+    onAmountChange: (String) -> Unit,
+    onAddressChange: (String) -> Unit,
+    onDeleteItemClick: () -> Unit,
+) {
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(vertical = 8.dp),
+    ) {
+        OutlinedTextField(
+            label = { Text("Recipient") },
+            singleLine = true,
+            value = address,
+            isError = address.isBlank(),
+            enabled = enabled,
+            onValueChange = onAddressChange,
+            modifier = Modifier.weight(1f),
+        )
+        OutlinedTextField(
+            label = { Text("Amount") },
+            placeholder = { Text("0.00") },
+            singleLine = true,
+            value = amount,
+            suffix = { Text(MoneroCurrency.SYMBOL) },
+            isError = amount.isBlank(),
+            enabled = enabled,
+            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Decimal),
+            onValueChange = onAmountChange,
+            modifier = Modifier
+                .weight(1f)
+                .padding(start = 8.dp),
+        )
+        IconButton(
+            onClick = onDeleteItemClick,
+            enabled = enabled && itemIndex > 0,
+            modifier = Modifier.padding(top = 12.dp),
+        ) {
+            Icon(imageVector = Icons.Default.Delete, contentDescription = "Delete")
+        }
+    }
+}
+
+@Preview
+@Composable
+private fun EditableRecipientListPreview() {
+    EditableRecipientList(
+        recipients = listOf(
+            "888tNkZrPN6JsEgekjMnABU4TBzc2Dt29EPAvkRxbANsAnjyPbb3iQ1YBRk1UXcdRsiKc9dhwMVgN5S9cQUiyoogDavup3H" to "0.01"
+        ),
+    )
+}

demo/android/src/main/kotlin/im/molly/monero/demo/ui/SendTabViewModel.kt

@@ -0,0 +1,141 @@
+package im.molly.monero.demo.ui
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import androidx.lifecycle.viewmodel.initializer
+import androidx.lifecycle.viewmodel.viewModelFactory
+import im.molly.monero.FeePriority
+import im.molly.monero.MoneroCurrency
+import im.molly.monero.PaymentDetail
+import im.molly.monero.PaymentRequest
+import im.molly.monero.PendingTransfer
+import im.molly.monero.PublicAddress
+import im.molly.monero.TransferRequest
+import im.molly.monero.demo.AppModule
+import im.molly.monero.demo.data.WalletRepository
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.stateIn
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+
+class SendTabViewModel(
+    private val walletId: Long,
+    private val walletRepository: WalletRepository = AppModule.walletRepository,
+) : ViewModel() {
+
+    private val viewModelState = MutableStateFlow(SendTabUiState())
+
+    val uiState = viewModelState.stateIn(
+        scope = viewModelScope,
+        started = SharingStarted.WhileSubscribed(5_000),
+        initialValue = viewModelState.value
+    )
+
+    fun updateAccount(accountIndex: Int) {
+        viewModelState.update {
+            it.copy(
+                accountIndex = accountIndex,
+                status = TransferStatus.Idle,
+            )
+        }
+    }
+
+    fun updatePriority(priority: FeePriority) {
+        viewModelState.update {
+            it.copy(
+                feePriority = priority,
+                status = TransferStatus.Idle,
+            )
+        }
+    }
+
+    fun updateRecipients(recipients: List<Pair<String, String>>) {
+        viewModelState.update {
+            it.copy(
+                recipients = recipients, status = TransferStatus.Idle
+            )
+        }
+    }
+
+    private fun getPaymentRequest(state: SendTabUiState): Result<PaymentRequest> {
+        return runCatching {
+            PaymentRequest(
+                spendingAccountIndex = state.accountIndex,
+                paymentDetails = state.recipients.map { (address, amount) ->
+                    PaymentDetail(
+                        recipientAddress = PublicAddress.parse(address),
+                        amount = MoneroCurrency.parse(amount),
+                    )
+                },
+                feePriority = state.feePriority,
+            )
+        }
+    }
+
+    fun createPayment() {
+        val result = getPaymentRequest(viewModelState.value)
+        result.fold(
+            onSuccess = { createTransfer(it) },
+            onFailure = { error ->
+                viewModelState.update {
+                    it.copy(status = TransferStatus.Error(error.message))
+                }
+            },
+        )
+    }
+
+    private fun createTransfer(transferRequest: TransferRequest) {
+        viewModelState.update {
+            it.copy(status = TransferStatus.Preparing)
+        }
+        viewModelScope.launch {
+            val pendingTransfer = runCatching {
+                walletRepository.createTransfer(walletId, transferRequest)
+            }
+            viewModelState.update {
+                val updatedState = pendingTransfer.fold(
+                    onSuccess = { pendingTransfer ->
+                        it.copy(status = TransferStatus.ReadyForApproval(pendingTransfer))
+                    },
+                    onFailure = { error ->
+                        it.copy(status = TransferStatus.Error(error.message))
+                    },
+                )
+                updatedState
+            }
+        }
+    }
+
+    fun confirmPayment() {
+        TODO()
+    }
+
+    companion object {
+        fun factory(walletId: Long) = viewModelFactory {
+            initializer {
+                SendTabViewModel(walletId)
+            }
+        }
+    }
+}
+
+data class SendTabUiState(
+    val accountIndex: Int = 0,
+    val recipients: List<Pair<String, String>> = emptyList(),
+    val feePriority: FeePriority = FeePriority.Medium,
+    val status: TransferStatus = TransferStatus.Idle,
+) {
+    val isInProgress: Boolean
+        get() = !(status == TransferStatus.Idle || status is TransferStatus.Error)
+}
+
+sealed interface TransferStatus {
+    data object Idle : TransferStatus
+    data object Preparing : TransferStatus
+    data class ReadyForApproval(
+        val pendingTransfer: PendingTransfer
+    ) : TransferStatus
+
+    data class Error(val errorMessage: String?) : TransferStatus
+}

demo/android/src/main/kotlin/im/molly/monero/demo/ui/WalletBalanceView.kt

@@ -7,7 +7,7 @@ import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
-import androidx.compose.material3.Divider
+import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -55,17 +55,17 @@ fun WalletBalanceView(
     ) {
         Text(
             style = MaterialTheme.typography.bodyLarge,
-            text = "Balance at ${blockchainTime}",
+            text = "Balance at $blockchainTime",
         )
 
         Spacer(modifier = Modifier.height(12.dp))
 
         BalanceRow("Confirmed", balance.confirmedAmount)
         BalanceRow("Pending", balance.pendingAmount)
-        Divider()
+        HorizontalDivider()
         BalanceRow("Total", balance.totalAmount)
 
-        val currentTime = blockchainTime.copy(timestamp = now)
+        val currentTime = blockchainTime.withTimestamp(now)
 
         BalanceRow("Unlocked", balance.unlockedAmountAt(currentTime))
         balance.lockedAmountsAt(currentTime).forEach { (timeSpan, amount) ->

demo/android/src/main/kotlin/im/molly/monero/demo/ui/WalletScreen.kt

@@ -3,6 +3,10 @@ package im.molly.monero.demo.ui
 import androidx.compose.foundation.layout.*
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.rememberLazyListState
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Info
 import androidx.compose.material3.*
 import androidx.compose.runtime.*
 import androidx.compose.runtime.saveable.rememberSaveable
@@ -19,14 +23,19 @@ import androidx.compose.ui.tooling.preview.PreviewParameterProvider
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewmodel.compose.viewModel
+import im.molly.monero.FeePriority
 import im.molly.monero.Ledger
 import im.molly.monero.MoneroCurrency
 import im.molly.monero.demo.data.model.WalletConfig
-import im.molly.monero.demo.ui.component.CopyableText
+import im.molly.monero.demo.ui.component.SelectListBox
 import im.molly.monero.demo.ui.component.Toolbar
 import im.molly.monero.demo.ui.preview.PreviewParameterData
 import im.molly.monero.demo.ui.theme.AppIcons
 import im.molly.monero.demo.ui.theme.AppTheme
+import im.molly.monero.toFormattedString
+import kotlinx.coroutines.delay
+import java.time.Instant
+import kotlin.time.Duration.Companion.seconds
 
 @Composable
 fun WalletRoute(
@@ -34,20 +43,32 @@ fun WalletRoute(
     onTransactionClick: (String, Long) -> Unit,
     onBackClick: () -> Unit,
     modifier: Modifier = Modifier,
-    viewModel: WalletViewModel = viewModel(
+    walletViewModel: WalletViewModel = viewModel(
         factory = WalletViewModel.factory(walletId),
         key = WalletViewModel.key(walletId),
-    )
+    ),
+    sendTabViewModel: SendTabViewModel = viewModel(
+        factory = SendTabViewModel.factory(walletId)
+    ),
 ) {
-    val uiState: WalletUiState by viewModel.uiState.collectAsStateWithLifecycle()
+    val walletUiState by walletViewModel.uiState.collectAsStateWithLifecycle()
+    val sendTabUiState by sendTabViewModel.uiState.collectAsStateWithLifecycle()
+
     WalletScreen(
-        uiState = uiState,
+        walletUiState = walletUiState,
-        onWalletConfigChange = { config -> viewModel.updateConfig(config) },
+        sendTabUiState = sendTabUiState,
-        onTransactionClick = onTransactionClick,
+        onWalletConfigChange = { config ->
-        onCreateAccountClick = { viewModel.createAccount() },
+            walletViewModel.updateConfig(config)
-        onCreateSubAddressClick = { accountIndex ->
-            viewModel.createSubAddress(accountIndex)
         },
+        onTransactionClick = onTransactionClick,
+        onCreateAccountClick = { walletViewModel.createAccount() },
+        onCreateSubAddressClick = { accountIndex ->
+            walletViewModel.createSubAddress(accountIndex)
+        },
+        onTransferAccountSelect = { sendTabViewModel.updateAccount(it) },
+        onTransferPrioritySelect = { sendTabViewModel.updatePriority(it) },
+        onTransferRecipientChange = { sendTabViewModel.updateRecipients(it) },
+        onTransferSendClick = { sendTabViewModel.createPayment() },
         onBackClick = onBackClick,
         modifier = modifier,
     )
@@ -55,21 +76,31 @@ fun WalletRoute(
 
 @Composable
 private fun WalletScreen(
-    uiState: WalletUiState,
+    walletUiState: WalletUiState,
-    onWalletConfigChange: (WalletConfig) -> Unit,
+    sendTabUiState: SendTabUiState,
-    onTransactionClick: (String, Long) -> Unit,
-    onCreateAccountClick: () -> Unit,
-    onCreateSubAddressClick: (Int) -> Unit,
-    onBackClick: () -> Unit,
     modifier: Modifier = Modifier,
+    onWalletConfigChange: (WalletConfig) -> Unit = {},
+    onTransactionClick: (String, Long) -> Unit = { _, _ -> },
+    onCreateAccountClick: () -> Unit = {},
+    onCreateSubAddressClick: (Int) -> Unit = {},
+    onTransferAccountSelect: (Int) -> Unit = {},
+    onTransferPrioritySelect: (FeePriority) -> Unit = {},
+    onTransferRecipientChange: (List<Pair<String, String>>) -> Unit = {},
+    onTransferSendClick: () -> Unit = {},
+    onBackClick: () -> Unit = {},
 ) {
-    when (uiState) {
+    when (walletUiState) {
         is WalletUiState.Loaded -> WalletScreenLoaded(
-            uiState = uiState,
+            walletUiState = walletUiState,
+            sendTabUiState = sendTabUiState,
             onWalletConfigChange = onWalletConfigChange,
             onTransactionClick = onTransactionClick,
             onCreateAccountClick = onCreateAccountClick,
             onCreateSubAddressClick = onCreateSubAddressClick,
+            onTransferAccountSelect = onTransferAccountSelect,
+            onTransferPrioritySelect = onTransferPrioritySelect,
+            onTransferRecipientChange = onTransferRecipientChange,
+            onTransferSendClick = onTransferSendClick,
             onBackClick = onBackClick,
             modifier = modifier,
         )
@@ -80,13 +111,33 @@ private fun WalletScreen(
 }
 
 @OptIn(ExperimentalMaterial3Api::class)
+@Composable
+private fun WalletToolbar(
+    onBackClick: () -> Unit,
+    actions: @Composable RowScope.() -> Unit = {},
+) {
+    Toolbar(navigationIcon = {
+        IconButton(onClick = onBackClick) {
+            Icon(
+                imageVector = AppIcons.ArrowBack,
+                contentDescription = "Back",
+            )
+        }
+    }, actions = actions)
+}
+
 @Composable
 private fun WalletScreenLoaded(
-    uiState: WalletUiState.Loaded,
+    walletUiState: WalletUiState.Loaded,
+    sendTabUiState: SendTabUiState,
     onWalletConfigChange: (WalletConfig) -> Unit,
     onTransactionClick: (String, Long) -> Unit,
     onCreateAccountClick: () -> Unit,
     onCreateSubAddressClick: (Int) -> Unit,
+    onTransferAccountSelect: (Int) -> Unit,
+    onTransferPrioritySelect: (FeePriority) -> Unit,
+    onTransferRecipientChange: (List<Pair<String, String>>) -> Unit,
+    onTransferSendClick: () -> Unit,
     onBackClick: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
@@ -96,14 +147,7 @@ private fun WalletScreenLoaded(
 
     Scaffold(
         topBar = {
-            Toolbar(navigationIcon = {
+            WalletToolbar(onBackClick = onBackClick, actions = {
-                IconButton(onClick = onBackClick) {
-                    Icon(
-                        imageVector = AppIcons.ArrowBack,
-                        contentDescription = "Back",
-                    )
-                }
-            }, actions = {
                 WalletKebabMenu(
                     onRenameClick = { showRenameDialog = true },
                     onDeleteClick = { },
@@ -122,11 +166,11 @@ private fun WalletScreenLoaded(
                 withStyle(style = SpanStyle(fontWeight = FontWeight.Bold)) {
                     append(
                         MoneroCurrency.Format(precision = 5)
-                            .format(uiState.balance.confirmedAmount)
+                            .format(walletUiState.totalBalance.confirmedAmount)
                     )
                 }
             })
-            Text(text = uiState.config.name, style = MaterialTheme.typography.headlineSmall)
+            Text(text = walletUiState.config.name, style = MaterialTheme.typography.headlineSmall)
 
             WalletHeaderTabs(
                 titles = listOf("Balance", "Send", "Receive", "History"),
@@ -137,12 +181,20 @@ private fun WalletScreenLoaded(
             when (selectedTabIndex) {
                 0 -> {
                     WalletBalanceView(
-                        balance = uiState.balance,
+                        balance = walletUiState.totalBalance,
-                        blockchainTime = uiState.blockchainTime
+                        blockchainTime = walletUiState.blockchainTime
                     )
                 }
 
-                1 -> {} // TODO
+                1 -> {
+                    WalletSendTab(
+                        walletUiState, sendTabUiState,
+                        onAccountSelect = onTransferAccountSelect,
+                        onPrioritySelect = onTransferPrioritySelect,
+                        onRecipientChange = onTransferRecipientChange,
+                        onSendClick = onTransferSendClick,
+                    )
+                }
 
                 2 -> {
                     val scrollState = rememberLazyListState()
@@ -151,17 +203,13 @@ private fun WalletScreenLoaded(
                         state = scrollState,
                     ) {
                         addressCardItems(
-                            items = uiState.addresses,
+                            items = walletUiState.addresses,
                             onCreateSubAddressClick = onCreateSubAddressClick,
                         )
                         item {
-                            Column(
+                            TextButton(
-                                modifier = Modifier.fillMaxWidth(),
-                                horizontalAlignment = Alignment.CenterHorizontally,
-                            ) {
-                                OutlinedButton(
                                 onClick = onCreateAccountClick,
-                                    modifier = modifier.padding(bottom = 16.dp),
+                                modifier = modifier.padding(start = 16.dp, bottom = 8.dp),
                             ) {
                                 Text(
                                     text = "Create new account",
@@ -171,16 +219,15 @@ private fun WalletScreenLoaded(
                         }
                     }
                 }
-                }
 
                 3 -> {
                     val scrollState = rememberLazyListState()
 
                     var lastTxId by remember { mutableStateOf("") }
-                    lastTxId = uiState.transactions.firstOrNull()?.transaction?.txId ?: ""
+                    lastTxId = walletUiState.transactions.firstOrNull()?.transaction?.txId ?: ""
 
                     LaunchedEffect(lastTxId) {
-                        if (uiState.transactions.isNotEmpty()) {
+                        if (walletUiState.transactions.isNotEmpty()) {
                             scrollState.scrollToItem(0)
                         }
                     }
@@ -189,7 +236,7 @@ private fun WalletScreenLoaded(
                         state = scrollState,
                     ) {
                         transactionCardItems(
-                            items = uiState.transactions,
+                            items = walletUiState.transactions,
                             onTransactionClick = onTransactionClick,
                         )
                     }
@@ -198,7 +245,7 @@ private fun WalletScreenLoaded(
         }
 
         if (showRenameDialog) {
-            var name by remember { mutableStateOf(uiState.config.name) }
+            var name by remember { mutableStateOf(walletUiState.config.name) }
             AlertDialog(
                 onDismissRequest = { showRenameDialog = false },
                 title = { Text("Enter wallet name") },
@@ -211,7 +258,7 @@ private fun WalletScreenLoaded(
                 },
                 confirmButton = {
                     TextButton(onClick = {
-                        onWalletConfigChange(uiState.config.copy(name = name))
+                        onWalletConfigChange(walletUiState.config.copy(name = name))
                         showRenameDialog = false
                     }) {
                         Text("Rename")
@@ -222,16 +269,100 @@ private fun WalletScreenLoaded(
     }
 }
 
+@Composable
+private fun WalletSendTab(
+    walletUiState: WalletUiState.Loaded,
+    sendTabUiState: SendTabUiState,
+    onAccountSelect: (Int) -> Unit,
+    onPrioritySelect: (FeePriority) -> Unit,
+    onRecipientChange: (List<Pair<String, String>>) -> Unit,
+    onSendClick: () -> Unit,
+) {
+    var now by remember { mutableStateOf(Instant.now()) }
+
+    LaunchedEffect(now) {
+        delay(2.seconds)
+        now = Instant.now()
+    }
+
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(16.dp)
+            .imePadding()
+            .verticalScroll(rememberScrollState()),
+    ) {
+        SelectListBox(
+            label = "Send from",
+            options = walletUiState.accountBalance.mapValues { (index, balance) ->
+                val currentTime = walletUiState.blockchainTime.withTimestamp(now)
+                val funds = balance.unlockedAmountAt(currentTime)
+                val fundsFormatted = funds.toFormattedString(appendSymbol = true)
+                "Account #$index : $fundsFormatted"
+            },
+            selectedOption = sendTabUiState.accountIndex,
+            onOptionClick = { option -> onAccountSelect(option) },
+            enabled = !sendTabUiState.isInProgress,
+        )
+        EditableRecipientList(
+            recipients = sendTabUiState.recipients,
+            onRecipientChange = onRecipientChange,
+            enabled = !sendTabUiState.isInProgress,
+        )
+        SelectListBox(
+            label = "Transaction priority",
+            options = FeePriority.entries.associateWith { it.name },
+            selectedOption = sendTabUiState.feePriority,
+            onOptionClick = { option -> onPrioritySelect(option) },
+            enabled = !sendTabUiState.isInProgress,
+        )
+
+        if (sendTabUiState.status is TransferStatus.Error) {
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                modifier = Modifier.padding(top = 24.dp),
+            ) {
+                Icon(
+                    imageVector = Icons.Default.Info,
+                    contentDescription = "Error Icon",
+                    tint = MaterialTheme.colorScheme.error,
+                    modifier = Modifier.padding(end = 8.dp),
+                )
+                Text(
+                    text = sendTabUiState.status.errorMessage
+                        ?: "Unspecific error",
+                    color = MaterialTheme.colorScheme.error,
+                )
+            }
+        }
+
+        ElevatedButton(
+            modifier = Modifier.padding(vertical = 24.dp),
+            onClick = onSendClick,
+            enabled = !sendTabUiState.isInProgress,
+        ) {
+            val text = when (sendTabUiState.status) {
+                TransferStatus.Preparing -> "Preparing..."
+                else -> "Send"
+            }
+            Text(text = text)
+        }
+
+    }
+}
+
 @Composable
 private fun WalletScreenError(
     onBackClick: () -> Unit,
 ) {
+    Scaffold(topBar = { WalletToolbar(onBackClick = onBackClick) }) {}
 }
 
 @Composable
 private fun WalletScreenLoading(
     onBackClick: () -> Unit,
 ) {
+    Scaffold(topBar = { WalletToolbar(onBackClick = onBackClick) }) {}
 }
 
 @Composable
@@ -300,7 +431,7 @@ private fun WalletScreenPopulated(
 ) {
     AppTheme {
         WalletScreen(
-            uiState = WalletUiState.Loaded(
+            walletUiState = WalletUiState.Loaded(
                 config = WalletConfig(
                     id = 0,
                     publicAddress = ledger.publicAddress.address,
@@ -309,21 +440,21 @@ private fun WalletScreenPopulated(
                     remoteNodes = emptySet(),
                 ),
                 network = ledger.publicAddress.network,
-                balance = ledger.balance,
+                totalBalance = ledger.getBalance(),
+                accountBalance = emptyMap(),
                 blockchainTime = ledger.checkedAt,
                 addresses = emptyList(),
                 transactions = emptyList(),
             ),
-            onWalletConfigChange = {},
+            sendTabUiState = SendTabUiState(
-            onTransactionClick = { _: String, _: Long -> },
+                accountIndex = 0,
-            onCreateAccountClick = {},
+                recipients = emptyList(),
-            onCreateSubAddressClick = {},
+                feePriority = FeePriority.Medium,
-            onBackClick = {},
+            )
         )
     }
 }
 
-private class WalletScreenPreviewParameterProvider :
+private class WalletScreenPreviewParameterProvider : PreviewParameterProvider<Ledger> {
-    PreviewParameterProvider<Ledger> {
     override val values = sequenceOf(PreviewParameterData.ledger)
 }

demo/android/src/main/kotlin/im/molly/monero/demo/ui/WalletViewModel.kt

@@ -74,13 +74,16 @@ private fun walletUiState(
             is Result.Success -> {
                 val config = result.data.first
                 val ledger = result.data.second
+                val accountBalance = List(ledger.indexedAccounts.size) { index ->
+                    index to ledger.getBalanceForAccount(index)
+                }.toMap()
                 val addresses =
-                    ledger.accountAddresses.groupBy { it.accountIndex }.flatMap { (_, group) ->
+                    ledger.indexedAccounts.flatMap { account ->
-                        group.sortedBy { it.subAddressIndex }.mapIndexed { index, address ->
+                        account.addresses.map { address ->
                             WalletAddress(
                                 address = address,
                                 used = address.isAddressUsed(ledger.transactions),
-                                isLastForAccount = index == group.size - 1,
+                                isLastForAccount = address === account.addresses.last(),
                             )
                         }
                     }
@@ -91,7 +94,8 @@ private fun walletUiState(
                     config = config,
                     network = ledger.publicAddress.network,
                     blockchainTime = ledger.checkedAt,
-                    balance = ledger.balance,
+                    totalBalance = ledger.getBalance(),
+                    accountBalance = accountBalance,
                     addresses = addresses,
                     transactions = transactions,
                 )
@@ -113,7 +117,8 @@ sealed interface WalletUiState {
         val config: WalletConfig,
         val network: MoneroNetwork,
         val blockchainTime: BlockchainTime,
-        val balance: Balance,
+        val totalBalance: Balance,
+        val accountBalance: Map<Int, Balance>,
         val addresses: List<WalletAddress>,
         val transactions: List<WalletTransaction>,
     ) : WalletUiState

demo/android/src/main/kotlin/im/molly/monero/demo/ui/component/SelectListBox.kt

@@ -7,12 +7,13 @@ import androidx.compose.ui.Modifier
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-fun SelectListBox(
+fun <T>SelectListBox(
     label: String,
-    options: List<String>,
+    options: Map<T, String>,
-    selectedOption: String,
+    selectedOption: T,
-    onOptionClick: (String) -> Unit,
+    onOptionClick: (T) -> Unit,
     modifier: Modifier = Modifier,
+    enabled: Boolean = true,
 ) {
     var expanded by remember { mutableStateOf(false) }
 
@@ -25,16 +26,19 @@ fun SelectListBox(
     ) {
         OutlinedTextField(
             readOnly = true,
-            value = selectedOption,
+            value = options.getValue(selectedOption),
             onValueChange = { },
+            enabled = enabled,
             modifier = Modifier
                 .fillMaxWidth()
                 .menuAnchor(),
             label = { Text(label) },
             trailingIcon = {
+                if (enabled) {
                     ExposedDropdownMenuDefaults.TrailingIcon(
                         expanded = expanded
                     )
+                }
             },
             colors = ExposedDropdownMenuDefaults.outlinedTextFieldColors(),
         )
@@ -45,13 +49,13 @@ fun SelectListBox(
             },
             modifier = Modifier.exposedDropdownSize(),
         ) {
-            options.forEach { selectionOption ->
+            options.forEach { (key, text) ->
                 DropdownMenuItem(
                     text = {
-                        Text(selectionOption)
+                        Text(text)
                     },
                     onClick = {
-                        onOptionClick(selectionOption)
+                        onOptionClick(key)
                         expanded = false
                     },
                 )

demo/android/src/main/kotlin/im/molly/monero/demo/ui/preview/PreviewParameterData.kt

@@ -40,9 +40,9 @@ object PreviewParameterData {
 
     val ledger = Ledger(
         publicAddress = PublicAddress.parse("4AYjQM9HoAFNUeC3cvSfgeAN89oMMpMqiByvunzSzhn97cj726rJj3x8hCbH58UnMqQJShczCxbpWRiCJQ3HCUDHLiKuo4T"),
-        accountAddresses = emptySet(),
+        indexedAccounts = emptyList(),
         transactionById = transactions.associateBy { it.txId },
-        enotes = emptySet(),
+        enoteSet = emptySet(),
         checkedAt = BlockchainTime(blockHeader = blockHeader, network = network),
     )
 }

lib/android/src/main/aidl/im/molly/monero/ITransferRequestCallback.aidl

@@ -19,5 +19,5 @@ oneway interface ITransferRequestCallback {
 //    void onTransactionTooBig();
 //    void onTransferError(String errorMessage);
 //    void onWalletInternalError(String errorMessage);
-//    void onUnexpectedError(String errorMessage);
+    void onUnexpectedError(String message);
 }

lib/android/src/main/cpp/wallet/jni_cache.cc

@@ -7,6 +7,7 @@ jmethodID HttpResponse_getBody;
 jmethodID HttpResponse_getCode;
 jmethodID HttpResponse_getContentType;
 jmethodID ITransferRequestCb_onTransferCreated;
+jmethodID ITransferRequestCb_onUnexpectedError;
 jmethodID Logger_logFromNative;
 jmethodID TxInfo_ctor;
 jmethodID WalletNative_createPendingTransfer;
@@ -41,6 +42,9 @@ void InitializeJniCache(JNIEnv* env) {
   ITransferRequestCb_onTransferCreated = GetMethodId(
       env, iTransferRequestCb,
       "onTransferCreated", "(Lim/molly/monero/IPendingTransfer;)V");
+  ITransferRequestCb_onUnexpectedError = GetMethodId(
+      env, iTransferRequestCb,
+      "onUnexpectedError", "(Ljava/lang/String;)V");
   Logger_logFromNative = GetMethodId(
       env, logger,
       "logFromNative", "(ILjava/lang/String;Ljava/lang/String;)V");

lib/android/src/main/cpp/wallet/jni_cache.h

@@ -14,6 +14,7 @@ extern jmethodID HttpResponse_getBody;
 extern jmethodID HttpResponse_getCode;
 extern jmethodID HttpResponse_getContentType;
 extern jmethodID ITransferRequestCb_onTransferCreated;
+extern jmethodID ITransferRequestCb_onUnexpectedError;
 extern jmethodID Logger_logFromNative;
 extern jmethodID TxInfo_ctor;
 extern jmethodID WalletNative_callRemoteNode;

lib/android/src/main/cpp/wallet/wallet.cc

@@ -874,9 +874,12 @@ Java_im_molly_monero_WalletNative_nativeCreatePayment(
 //  } catch (error::transfer_error& e) {
 //  } catch (error::wallet_internal_error& e) {
 //  } catch (error::wallet_logic_error& e) {
-//  } catch (const std::exception& e) {
+  } catch (const std::exception& e) {
-  } catch (...) {
+    LOGW("Caught unhandled exception: %s", e.what());
-    LOG_FATAL("Caught unknown exception");
+    CallVoidMethod(env, j_callback,
+                   ITransferRequestCb_onUnexpectedError,
+                   NativeToJavaString(env, e.what()));
+    return;
   }
 
   jobject j_pending_transfer = CallObjectMethod(

lib/android/src/main/kotlin/im/molly/monero/BlockchainTime.kt

@@ -30,6 +30,10 @@ data class BlockchainTime(
         }
     }
 
+    fun withTimestamp(newTimestamp: Instant): BlockchainTime {
+        return copy(timestamp = newTimestamp)
+    }
+
     fun estimateHeight(targetTimestamp: Instant): Int {
         val timeDiff = Duration.between(timestamp, targetTimestamp)
         val estHeight = timeDiff.seconds / network.avgBlockTime(height).seconds + height

lib/android/src/main/kotlin/im/molly/monero/MoneroWallet.kt

@@ -4,14 +4,15 @@ import im.molly.monero.internal.TxInfo
 import im.molly.monero.internal.consolidateTransactions
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.channels.awaitClose
-import kotlinx.coroutines.channels.onFailure
 import kotlinx.coroutines.channels.trySendBlocking
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.callbackFlow
 import kotlinx.coroutines.flow.conflate
+import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.suspendCancellableCoroutine
+import kotlin.coroutines.resumeWithException
 import kotlin.time.Duration.Companion.seconds
 
 @OptIn(ExperimentalCoroutinesApi::class)
@@ -191,6 +192,12 @@ class MoneroWallet internal constructor(
                         pendingTransfer.close()
                     }
                 }
+
+                override fun onUnexpectedError(message: String) {
+                    continuation.resumeWithException(
+                        IllegalStateException(message)
+                    )
+                }
             }
             when (transferRequest) {
                 is PaymentRequest -> wallet.createPayment(transferRequest, callback)

lib/android/src/main/kotlin/im/molly/monero/TransferRequest.kt

@@ -8,7 +8,7 @@ sealed interface TransferRequest : Parcelable
 @Parcelize
 data class PaymentRequest(
     val paymentDetails: List<PaymentDetail>,
-    val sourceAccounts: Set<AccountAddress>,
+    val spendingAccountIndex: Int,
     val feePriority: FeePriority? = null,
     val timeLock: UnlockTime? = null,
 ) : TransferRequest

lib/android/src/main/kotlin/im/molly/monero/WalletNative.kt

@@ -187,7 +187,7 @@ internal class WalletNative private constructor(
                 amounts = amounts.toLongArray(),
                 timeLock = request.timeLock?.blockchainTime?.toLong() ?: 0,
                 priority = request.feePriority?.priority ?: 0,
-                accountIndex = 0,
+                accountIndex = request.spendingAccountIndex,
                 subAddressIndexes = IntArray(0),
                 callback = callback,
             )