cw-62: Sending ALL should fill in approximate USD value

cw_bitcoin/lib/electrum_fee_estimate.dart

@@ -0,0 +1,20 @@
+import 'package:cw_bitcoin/electrum_wallet.dart';
+import 'package:cw_core/fee_estimate.dart';
+import 'package:cw_core/transaction_priority.dart';
+
+class ElectrumFeeEstimate extends FeeEstimate {
+  ElectrumFeeEstimate(ElectrumWalletBase wallet)
+    : _wallet = wallet;
+
+  ElectrumWalletBase _wallet;
+
+  int get({TransactionPriority priority, int amount, int outputsCount}) {
+    // Electrum doesn't require an async call to obtain the estimated fee.
+    // We don't bother caching and just obtain it directly.
+    return _wallet.calculateEstimatedFee(priority,amount, outputsCount: outputsCount);
+  }
+
+  void update({TransactionPriority priority, int amount, int outputsCount}) {}
+
+  void set({TransactionPriority priority, int outputsCount, int fee}) {}
+}

cw_bitcoin/lib/electrum_wallet.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:convert';
 import 'dart:math';
 import 'dart:typed_data';
+import 'package:cw_core/fee_estimate.dart';
 import 'package:cw_core/unspent_coins_info.dart';
 import 'package:hive/hive.dart';
 import 'package:cw_bitcoin/electrum_wallet_addresses.dart';
@@ -33,6 +34,7 @@ import 'package:cw_core/transaction_priority.dart';
 import 'package:cw_core/wallet_info.dart';
 import 'package:cw_bitcoin/electrum.dart';
 import 'package:hex/hex.dart';
+import 'package:cw_bitcoin/electrum_fee_estimate.dart';
 
 part 'electrum_wallet.g.dart';
 
@@ -66,6 +68,7 @@ abstract class ElectrumWalletBase extends WalletBase<ElectrumBalance,
         ElectrumTransactionHistory(walletInfo: walletInfo, password: password);
     unspentCoins = [];
     _scripthashesUpdateSubject = {};
+    feeEstimate = ElectrumFeeEstimate(this);
   }
 
   static int estimatedTransactionSize(int inputsCount, int outputsCounts) =>
@@ -88,6 +91,10 @@ abstract class ElectrumWalletBase extends WalletBase<ElectrumBalance,
   @observable
   SyncStatus syncStatus;
 
+  @override
+  @observable
+  ElectrumFeeEstimate feeEstimate;
+
   List<String> get scriptHashes => walletAddresses.addresses
       .map((addr) => scriptHash(addr.address, networkType: networkType))
       .toList();
@@ -346,8 +353,7 @@ abstract class ElectrumWalletBase extends WalletBase<ElectrumBalance,
       feeRate(priority) * estimatedTransactionSize(inputsCount, outputsCount);
 
   @override
-  int calculateEstimatedFee(TransactionPriority priority, int amount,
-  {int outputsCount}) {
+  int calculateEstimatedFee(TransactionPriority priority, int amount, {int outputsCount = 1}) {
     if (priority is BitcoinTransactionPriority) {
       int inputsCount = 0;
 

cw_core/lib/fee_estimate.dart

@@ -0,0 +1,10 @@
+import 'package:cw_core/transaction_priority.dart';
+
+abstract class FeeEstimate
+{
+  void update({TransactionPriority priority, int outputsCount});
+
+  int get({TransactionPriority priority, int amount, int outputsCount});
+
+  void set({TransactionPriority priority, int outputsCount, int fee});
+}

cw_core/lib/wallet_base.dart

@@ -1,4 +1,5 @@
 import 'package:cw_core/balance.dart';
+import 'package:cw_core/fee_estimate.dart';
 import 'package:cw_core/transaction_info.dart';
 import 'package:cw_core/transaction_priority.dart';
 import 'package:cw_core/wallet_addresses.dart';
@@ -39,6 +40,8 @@ abstract class WalletBase<
 
   SyncStatus get syncStatus;
 
+  FeeEstimate get feeEstimate;
+
   set syncStatus(SyncStatus status);
 
   String get seed;
@@ -55,8 +58,6 @@ abstract class WalletBase<
 
   Future<PendingTransaction> createTransaction(Object credentials);
 
-  int calculateEstimatedFee(TransactionPriority priority, int amount);
-
   // void fetchTransactionsAsync(
   //     void Function(TransactionType transaction) onTransactionLoaded,
   //     {void Function() onFinished});

cw_monero/ios/Classes/monero_api.cpp

@@ -766,6 +766,25 @@ extern "C"
         return strdup(m_wallet->getTxKey(std::string(txId)).c_str());
     }
 
+    uint64_t estimate_transaction_fee(int outputs, uint8_t priority_raw)
+    {
+        // estimateTransactionFee only cares about the number of outputs
+        std::vector<std::pair<std::string, uint64_t>> destinations;
+        for (int i = 0; i < outputs; i++) {
+            destinations.push_back({"", 0});
+        }
+        auto priority = static_cast<Monero::PendingTransaction::Priority>(priority_raw);
+
+        try {
+           return m_wallet->estimateTransactionFee(destinations, priority);
+        }
+        catch (...) {
+            // estimateTransactionFee can throw an exception if there is a problem with the
+            // network request. We must catch it here because exceptions don't propagate to Dart.
+            return 0;
+        }
+    }
+
 #ifdef __cplusplus
 }
 #endif

cw_monero/lib/api/signatures.dart

@@ -120,3 +120,7 @@ typedef close_current_wallet = Void Function();
 typedef on_startup = Void Function();
 
 typedef rescan_blockchain = Void Function();
+
+typedef estimate_transaction_fee = Int64 Function(
+    Int32 outputs,
+    Int8 priorityRaw);

cw_monero/lib/api/types.dart

@@ -118,3 +118,5 @@ typedef CloseCurrentWallet = void Function();
 typedef OnStartup = void Function();
 
 typedef RescanBlockchainAsync = void Function();
+
+typedef EstimateTransactionFee = int Function(int, int);

cw_monero/lib/api/wallet.dart

@@ -112,6 +112,10 @@ final rescanBlockchainAsyncNative = moneroApi
     .lookup<NativeFunction<rescan_blockchain>>('rescan_blockchain')
     .asFunction<RescanBlockchainAsync>();
 
+final estimateTransactionFeeNative = moneroApi
+    .lookup<NativeFunction<estimate_transaction_fee>>('estimate_transaction_fee')
+    .asFunction<EstimateTransactionFee>();
+
 int getSyncingHeight() => getSyncingHeightNative();
 
 bool isNeededToRefresh() => isNeededToRefreshNative() != 0;
@@ -327,3 +331,18 @@ Future<bool> isConnected() => compute(_isConnected, 0);
 Future<int> getNodeHeight() => compute(_getNodeHeight, 0);
 
 void rescanBlockchainAsync() => rescanBlockchainAsyncNative();
+
+int estimateTransactionFeeSync(int outputs, int priorityRaw) {
+  return estimateTransactionFeeNative(outputs, priorityRaw);
+}
+
+int _estimateTransactionFee(Map args) {
+  final priorityRaw = args['priorityRaw'] as int;
+  final outputsCount = args['outputsCount'] as int;
+
+  return estimateTransactionFeeSync(outputsCount, priorityRaw);
+}
+
+Future<int> estimateTransactionFee({int priorityRaw, int outputsCount}) {
+  return compute(_estimateTransactionFee, {'priorityRaw': priorityRaw, 'outputsCount': outputsCount});
+}

cw_monero/lib/monero_fee_estimate.dart

@@ -0,0 +1,38 @@
+import 'package:mobx/mobx.dart';
+import 'package:cw_core/fee_estimate.dart';
+import 'package:cw_core/transaction_priority.dart';
+import 'package:cw_monero/api/wallet.dart' as monero_wallet;
+
+part 'monero_fee_estimate.g.dart';
+
+class MoneroFeeEstimate = _MoneroFeeEstimate with _$MoneroFeeEstimate;
+
+abstract class _MoneroFeeEstimate extends FeeEstimate with Store {
+  _MoneroFeeEstimate()
+      : _estimatedFee = new ObservableMap<String, int>();
+
+  @observable
+  ObservableMap<String, int> _estimatedFee;
+
+  @override
+  void update({TransactionPriority priority, int outputsCount}) {
+    Future(() async {
+      final fee = await monero_wallet.estimateTransactionFee(priorityRaw: priority.raw, outputsCount: outputsCount);
+      set(priority: priority, fee: fee, outputsCount: outputsCount);
+    });
+  }
+
+  @override
+  int get({TransactionPriority priority, int amount, int outputsCount}) {
+    return _estimatedFee[_key(priority, outputsCount)] ?? 0;
+  }
+
+  @override
+  void set({TransactionPriority priority, int outputsCount, int fee}) {
+    _estimatedFee[_key(priority, outputsCount)] = fee;
+  }
+
+  String _key(TransactionPriority priority, int outputsCount) {
+    return "$priority:$outputsCount";
+  }
+}

cw_monero/lib/monero_wallet.dart

@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'package:cw_core/transaction_priority.dart';
 import 'package:cw_monero/monero_amount_format.dart';
 import 'package:cw_monero/monero_transaction_creation_exception.dart';
 import 'package:cw_monero/monero_transaction_info.dart';
@@ -18,6 +17,7 @@ import 'package:cw_monero/monero_transaction_creation_credentials.dart';
 import 'package:cw_monero/pending_monero_transaction.dart';
 import 'package:cw_monero/monero_wallet_keys.dart';
 import 'package:cw_monero/monero_balance.dart';
+import 'package:cw_monero/monero_fee_estimate.dart';
 import 'package:cw_monero/monero_transaction_history.dart';
 import 'package:cw_monero/account.dart';
 import 'package:cw_core/pending_transaction.dart';
@@ -25,7 +25,6 @@ import 'package:cw_core/wallet_base.dart';
 import 'package:cw_core/sync_status.dart';
 import 'package:cw_core/wallet_info.dart';
 import 'package:cw_core/node.dart';
-import 'package:cw_monero/monero_transaction_priority.dart';
 
 part 'monero_wallet.g.dart';
 
@@ -52,6 +51,7 @@ abstract class MoneroWalletBase extends WalletBase<MoneroBalance,
               monero_wallet.getUnlockedBalance(accountIndex: account.id));
       walletAddresses.updateSubaddressList(accountIndex: account.id);
     });
+    feeEstimate = MoneroFeeEstimate();
   }
 
   static const int _autoSaveInterval = 30;
@@ -67,6 +67,9 @@ abstract class MoneroWalletBase extends WalletBase<MoneroBalance,
   @observable
   MoneroBalance balance;
 
+  @override
+  MoneroFeeEstimate feeEstimate;
+
   @override
   String get seed => monero_wallet.getSeed();
 
@@ -221,28 +224,6 @@ abstract class MoneroWalletBase extends WalletBase<MoneroBalance,
     return PendingMoneroTransaction(pendingTransactionDescription);
   }
 
-  @override
-  int calculateEstimatedFee(TransactionPriority priority, int amount) {
-    // FIXME: hardcoded value;
-
-    if (priority is MoneroTransactionPriority) {
-      switch (priority) {
-        case MoneroTransactionPriority.slow:
-          return 24590000;
-        case MoneroTransactionPriority.regular:
-          return 123050000;
-        case MoneroTransactionPriority.medium:
-          return 245029999;
-        case MoneroTransactionPriority.fast:
-          return 614530000;
-        case MoneroTransactionPriority.fastest:
-          return 26021600000;
-      }
-    }
-
-    return 0;
-  }
-
   @override
   Future<void> save() async {
     await walletAddresses.updateAddressesInBox();

lib/entities/format_amount.dart

@@ -1,3 +1,7 @@
+import 'package:cake_wallet/bitcoin/bitcoin.dart';
+import 'package:cake_wallet/monero/monero.dart';
+import 'package:cw_core/wallet_type.dart';
+
 String formatAmount(String amount) {
   if ((!amount.contains('.'))&&(!amount.contains(','))) {
     return amount + '.00';
@@ -6,3 +10,15 @@ String formatAmount(String amount) {
   }
   return amount;
 }
+
+double formatAmountToDouble({WalletType type, int amount}) {
+  if (type == WalletType.bitcoin || type == WalletType.litecoin) {
+    return bitcoin.formatterBitcoinAmountToDouble(amount: amount);
+  }
+
+  if (type == WalletType.monero) {
+    return monero.formatterMoneroAmountToDouble(amount: amount);
+  }
+
+  return 0.0;
+}

lib/reactions/on_current_wallet_change.dart

@@ -51,7 +51,7 @@ void startCurrentWalletChangeReaction(AppStore appStore,
       wallet) async {
     try {
       final node = settingsStore.getCurrentNode(wallet.type);
-      startWalletSyncStatusChangeReaction(wallet);
+      startWalletSyncStatusChangeReaction(wallet, settingsStore);
       startCheckConnectionReaction(wallet, settingsStore);
       await getIt
           .get<SharedPreferences>()

lib/reactions/on_wallet_sync_status_change.dart

@@ -1,5 +1,9 @@
 import 'package:cake_wallet/di.dart';
 import 'package:cake_wallet/entities/wake_lock.dart';
+import 'package:cake_wallet/store/settings_store.dart';
+import 'package:cw_core/transaction_priority.dart';
+import 'package:cw_core/wallet_type.dart';
+import 'package:cw_monero/monero_transaction_priority.dart';
 import 'package:mobx/mobx.dart';
 import 'package:cw_core/transaction_history.dart';
 import 'package:cw_core/wallet_base.dart';
@@ -10,10 +14,7 @@ import 'package:flutter/services.dart';
 
 ReactionDisposer _onWalletSyncStatusChangeReaction;
 
-void startWalletSyncStatusChangeReaction(
-    WalletBase<Balance, TransactionHistoryBase<TransactionInfo>,
-            TransactionInfo>
-        wallet) {
+void startWalletSyncStatusChangeReaction(WalletBase<Balance, TransactionHistoryBase<TransactionInfo>, TransactionInfo> wallet, SettingsStore settingsStore) {
   final _wakeLock = getIt.get<WakeLock>();
   _onWalletSyncStatusChangeReaction?.reaction?.dispose();
   _onWalletSyncStatusChangeReaction =
@@ -27,5 +28,9 @@ void startWalletSyncStatusChangeReaction(
     if (status is SyncedSyncStatus || status is FailedSyncStatus) {
       await _wakeLock.disableWake();
     }
+
+    if (status is SyncedSyncStatus) {
+      wallet.feeEstimate.update(priority: settingsStore.priority[wallet.type], outputsCount: 1);
+    }
   });
 }

lib/src/screens/send/send_page.dart

@@ -261,6 +261,7 @@ class SendPage extends BasePage {
                   child: PrimaryButton(
                     onPressed: () {
                       sendViewModel.addOutput();
+                      sendViewModel.estimateFee();
                       Future.delayed(const Duration(milliseconds: 250), () {
                         controller.jumpToPage(sendViewModel.outputs.length - 1);
                       });

lib/src/screens/send/widgets/send_card.dart

@@ -386,12 +386,7 @@ class SendCardState extends State<SendCard>
                                         crossAxisAlignment: CrossAxisAlignment.end,
                                         children: [
                                           Text(
-                                              output
-                                                  .estimatedFee
-                                                  .toString() +
-                                                  ' ' +
-                                                  sendViewModel
-                                                      .currency.title,
+                                              sendViewModel.estimatedFee.toString() + ' ' + sendViewModel.currency.title,
                                               style: TextStyle(
                                                   fontSize: 12,
                                                   fontWeight:
@@ -403,11 +398,7 @@ class SendCardState extends State<SendCard>
                                               padding:
                                               EdgeInsets.only(top: 5),
                                               child: Text(
-                                                  output
-                                                      .estimatedFeeFiatAmount
-                                                      +  ' ' +
-                                                      sendViewModel
-                                                          .fiat.title,
+                                                  sendViewModel.estimatedFeeFiatAmount + ' ' + sendViewModel.fiat.title,
                                                   style: TextStyle(
                                                       fontSize: 12,
                                                       fontWeight:
@@ -513,10 +504,16 @@ class SendCardState extends State<SendCard>
       }
     });
 
+    reaction((_) => sendViewModel.estimatedFee, (double estimatedFee) {
+      final firstOutput = sendViewModel.outputs[0];
+      if (firstOutput != null && firstOutput.sendAll) {
+        firstOutput.updateFiatAmount();
+      }
+    });
+
     reaction((_) => output.sendAll, (bool all) {
       if (all) {
         cryptoAmountController.text = S.current.all;
-        fiatAmountController.text = null;
       }
     });
 

lib/view_model/exchange/exchange_view_model.dart

@@ -340,7 +340,7 @@ abstract class ExchangeViewModelBase with Store {
     if (wallet.type == WalletType.bitcoin) {
       final availableBalance = wallet.balance.available;
       final priority = _settingsStore.priority[wallet.type];
-      final fee = wallet.calculateEstimatedFee(priority, null);
+      final fee = wallet.feeEstimate.get(priority: priority);
 
       if (availableBalance < fee || availableBalance == 0) {
         return;

lib/view_model/send/output.dart

@@ -1,5 +1,6 @@
+import 'dart:math';
 import 'package:cake_wallet/di.dart';
-import 'package:cake_wallet/entities/calculate_fiat_amount_raw.dart';
+import 'package:cake_wallet/entities/format_amount.dart';
 import 'package:cake_wallet/entities/parse_address_from_domain.dart';
 import 'package:cake_wallet/entities/parsed_address.dart';
 import 'package:cake_wallet/src/screens/send/widgets/extract_address_from_parsed.dart';
@@ -92,39 +93,6 @@ abstract class OutputBase with Store {
     return amount;
   }
 
-  @computed
-  double get estimatedFee {
-    try {
-      final fee = _wallet.calculateEstimatedFee(
-          _settingsStore.priority[_wallet.type], formattedCryptoAmount);
-
-      if (_wallet.type == WalletType.bitcoin ||
-          _wallet.type == WalletType.litecoin) {
-        return bitcoin.formatterBitcoinAmountToDouble(amount: fee);
-      }
-
-      if (_wallet.type == WalletType.monero) {
-        return monero.formatterMoneroAmountToDouble(amount: fee);
-      }
-    } catch (e) {
-      print(e.toString());
-    }
-
-    return 0;
-  }
-
-  @computed
-  String get estimatedFeeFiatAmount {
-    try {
-      final fiat = calculateFiatAmountRaw(
-          price: _fiatConversationStore.prices[_wallet.currency],
-          cryptoAmount: estimatedFee);
-      return fiat;
-    } catch (_) {
-      return '0.00';
-    }
-  }
-
   WalletType get walletType => _wallet.type;
   final WalletBase _wallet;
   final SettingsStore _settingsStore;
@@ -156,7 +124,7 @@ abstract class OutputBase with Store {
     }
 
     cryptoAmount = amount;
-    _updateFiatAmount();
+    updateFiatAmount();
   }
 
   @action
@@ -166,11 +134,11 @@ abstract class OutputBase with Store {
   }
 
   @action
-  void _updateFiatAmount() {
+  void updateFiatAmount() {
     try {
       final fiat = calculateFiatAmount(
           price: _fiatConversationStore.prices[_wallet.currency],
-          cryptoAmount: cryptoAmount.replaceAll(',', '.'));
+          cryptoAmount: (cryptoAmount.toUpperCase() == S.current.all) ? _cryptoNumberFormat.format(formatAmountToDouble(type: _wallet.type, amount: _estimateAmountAll())) : cryptoAmount.replaceAll(',', '.'));
       if (fiatAmount != fiat) {
         fiatAmount = fiat;
       }
@@ -214,6 +182,11 @@ abstract class OutputBase with Store {
     _cryptoNumberFormat.maximumFractionDigits = maximumFractionDigits;
   }
 
+  int _estimateAmountAll() {
+    final fee = _wallet.feeEstimate.get(priority: _settingsStore.priority[_wallet.type], outputsCount: 1);
+    return max(0, _wallet.balance.available - fee);
+  }
+
   Future<void> fetchParsedAddress(BuildContext context) async {
     final domain = address;
     final ticker = _wallet.currency.title.toLowerCase();

lib/view_model/send/send_view_model.dart

@@ -1,4 +1,5 @@
 import 'package:cake_wallet/entities/balance_display_mode.dart';
+import 'package:cake_wallet/entities/format_amount.dart';
 import 'package:cake_wallet/entities/transaction_description.dart';
 import 'package:cw_core/transaction_priority.dart';
 import 'package:cake_wallet/view_model/send/output.dart';
@@ -24,6 +25,7 @@ import 'package:cake_wallet/store/settings_store.dart';
 import 'package:cake_wallet/view_model/send/send_view_model_state.dart';
 import 'package:cake_wallet/entities/parsed_address.dart';
 import 'package:cake_wallet/bitcoin/bitcoin.dart';
+import 'package:cake_wallet/entities/calculate_fiat_amount_raw.dart';
 
 part 'send_view_model.g.dart';
 
@@ -46,6 +48,10 @@ abstract class SendViewModelBase with Store {
 
     outputs = ObservableList<Output>()
       ..add(Output(_wallet, _settingsStore, _fiatConversationStore));
+
+    _settingsStore.priority.observe((change) async {
+      _wallet.feeEstimate.update(priority: change.newValue, outputsCount: outputs.length);
+    });
   }
 
   @observable
@@ -240,4 +246,38 @@ abstract class SendViewModelBase with Store {
 
   bool _isEqualCurrency(String currency) => 
       currency.toLowerCase() == _wallet.currency.title.toLowerCase();
+
+  void estimateFee() {
+    _wallet.feeEstimate.update(priority: _settingsStore.priority[_wallet.type], outputsCount: outputs.length);
+  }
+
+  @computed
+  double get estimatedFee {
+    try {
+      var totalFormattedCryptoAmount = 0;
+      for (final output in outputs) {
+        totalFormattedCryptoAmount += output.formattedCryptoAmount;
+      }
+
+      final fee = _wallet.feeEstimate.get(priority: _settingsStore.priority[_wallet.type], amount: totalFormattedCryptoAmount, outputsCount: outputs.length);
+
+      return formatAmountToDouble(type: _wallet.type, amount: fee);
+    } catch (e) {
+      print(e.toString());
+    }
+
+    return 0;
+  }
+
+  @computed
+  String get estimatedFeeFiatAmount {
+    try {
+      final fiat = calculateFiatAmountRaw(
+          price: _fiatConversationStore.prices[_wallet.currency],
+          cryptoAmount: this.estimatedFee);
+      return fiat;
+    } catch (_) {
+      return '0.00';
+    }
+  }
 }