[Qt] sendcoinsdialog: convert QMessageBox usage to message()

- add new processSendCoinsReturn() function, which parses the
  status of WalletModel::SendCoinsReturn and generates a pair consisting
  of a message and message flags
- result is we only need one emit message() call
- this change ensures that the GUI is shown for warnings/errors in
  sendcoinsdialog, because of message() taking care of that for modal
  messages
- changes 2 warning message into error messages and removed "Error:"
  in front of the actual error message string

2 files changed, 65 insertions, 53 deletions

diff --git a/src/qt/sendcoinsdialog.cpp b/src/qt/sendcoinsdialog.cpp
index d574eb73f9..51304bc05c 100644
--- a/src/qt/sendcoinsdialog.cpp
+++ b/src/qt/sendcoinsdialog.cpp
@@ -1,13 +1,13 @@
 #include "sendcoinsdialog.h"
 #include "ui_sendcoinsdialog.h"
 
-#include "walletmodel.h"
 #include "bitcoinunits.h"
 #include "optionsmodel.h"
 #include "sendcoinsentry.h"
 #include "guiutil.h"
 #include "askpassphrasedialog.h"
 #include "base58.h"
+#include "ui_interface.h"
 
 #include <QMessageBox>
 #include <QTextDocument>
@@ -136,41 +136,9 @@ void SendCoinsDialog::on_sendButton_clicked()
     // prepare transaction for getting txFee earlier
     WalletModelTransaction currentTransaction(recipients);
     WalletModel::SendCoinsReturn prepareStatus = model->prepareTransaction(currentTransaction);
-
-    QString strSendCoins = tr("Send Coins");
-    switch(prepareStatus.status)
-    {
-    case WalletModel::InvalidAddress:
-        QMessageBox::warning(this, strSendCoins,
-            tr("The recipient address is not valid, please recheck."));
-        break;
-    case WalletModel::InvalidAmount:
-        QMessageBox::warning(this, strSendCoins,
-            tr("The amount to pay must be larger than 0."));
-        break;
-    case WalletModel::AmountExceedsBalance:
-        QMessageBox::warning(this, strSendCoins,
-            tr("The amount exceeds your balance."));
-        break;
-    case WalletModel::AmountWithFeeExceedsBalance:
-        QMessageBox::warning(this, strSendCoins,
-            tr("The total exceeds your balance when the %1 transaction fee is included.").
-            arg(BitcoinUnits::formatWithUnit(model->getOptionsModel()->getDisplayUnit(), currentTransaction.getTransactionFee())));
-        break;
-    case WalletModel::DuplicateAddress:
-        QMessageBox::warning(this, strSendCoins,
-            tr("Duplicate address found, can only send to each address once per send operation."));
-        break;
-    case WalletModel::TransactionCreationFailed:
-        QMessageBox::warning(this, strSendCoins,
-            tr("Error: Transaction creation failed!"));
-        break;
-    case WalletModel::TransactionCommitFailed:
-    case WalletModel::OK:
-    case WalletModel::Aborted: // User aborted, nothing to do
-    default:
-        break;
-    }
+    // process prepareStatus and on error generate message shown to user
+    processSendCoinsReturn(prepareStatus,
+        BitcoinUnits::formatWithUnit(model->getOptionsModel()->getDisplayUnit(), currentTransaction.getTransactionFee()));
 
     if(prepareStatus.status != WalletModel::OK) {
         fNewRecipientAllowed = true;
@@ -208,19 +176,13 @@ void SendCoinsDialog::on_sendButton_clicked()
     }
 
     // now send the prepared transaction
-    WalletModel::SendCoinsReturn sendstatus = model->sendCoins(currentTransaction);
-    switch(sendstatus.status)
+    WalletModel::SendCoinsReturn sendStatus = model->sendCoins(currentTransaction);
+    // process sendStatus and on error generate message shown to user
+    processSendCoinsReturn(sendStatus);
+
+    if (sendStatus.status == WalletModel::OK)
     {
-    case WalletModel::TransactionCommitFailed:
-        QMessageBox::warning(this, strSendCoins,
-            tr("Error: The transaction was rejected. This might happen if some of the coins in your wallet were already spent, such as if you used a copy of wallet.dat and coins were spent in the copy but not marked as spent here."));
-        break;
-    case WalletModel::OK:
         accept();
-        break;
-    case WalletModel::Aborted: // User aborted, nothing to do
-    default:
-        break;
     }
     fNewRecipientAllowed = true;
 }
@@ -356,16 +318,16 @@ bool SendCoinsDialog::handlePaymentRequest(const SendCoinsRecipient &rv)
         const payments::PaymentDetails& details = rv.paymentRequest.getDetails();
         if (details.has_expires() && (int64)details.expires() < GetTime())
         {
-            QMessageBox::warning(this, strSendCoins,
-                tr("Payment request expired"));
+            emit message(strSendCoins, tr("Payment request expired"),
+                CClientUIInterface::MSG_WARNING);
             return false;
         }
     }
     else {
         CBitcoinAddress address(rv.address.toStdString());
         if (!address.IsValid()) {
-            QMessageBox::warning(this, strSendCoins,
-                tr("Invalid payment address %1").arg(rv.address));
+            emit message(strSendCoins, tr("Invalid payment address %1").arg(rv.address),
+                CClientUIInterface::MSG_WARNING);
             return false;
         }
     }
@@ -389,3 +351,47 @@ void SendCoinsDialog::updateDisplayUnit()
 {
     setBalance(model->getBalance(), 0, 0);
 }
+
+void SendCoinsDialog::processSendCoinsReturn(const WalletModel::SendCoinsReturn &sendCoinsReturn, const QString &msgArg)
+{
+    QPair<QString, CClientUIInterface::MessageBoxFlags> msgParams;
+    // Default to a warning message, override if error message is needed
+    msgParams.second = CClientUIInterface::MSG_WARNING;
+
+    // This comment is specific to SendCoinsDialog usage of WalletModel::SendCoinsReturn.
+    // WalletModel::TransactionCommitFailed is used only in WalletModel::sendCoins()
+    // all others are used only in WalletModel::prepareTransaction()
+    switch(sendCoinsReturn.status)
+    {
+    case WalletModel::InvalidAddress:
+        msgParams.first = tr("The recipient address is not valid, please recheck.");
+        break;
+    case WalletModel::InvalidAmount:
+        msgParams.first = tr("The amount to pay must be larger than 0.");
+        break;
+    case WalletModel::AmountExceedsBalance:
+        msgParams.first = tr("The amount exceeds your balance.");
+        break;
+    case WalletModel::AmountWithFeeExceedsBalance:
+        msgParams.first = tr("The total exceeds your balance when the %1 transaction fee is included.").arg(msgArg);
+        break;
+    case WalletModel::DuplicateAddress:
+        msgParams.first = tr("Duplicate address found, can only send to each address once per send operation.");
+        break;
+    case WalletModel::TransactionCreationFailed:
+        msgParams.first = tr("Transaction creation failed!");
+        msgParams.second = CClientUIInterface::MSG_ERROR;
+        break;
+    case WalletModel::TransactionCommitFailed:
+        msgParams.first = tr("The transaction was rejected! This might happen if some of the coins in your wallet were already spent, such as if you used a copy of wallet.dat and coins were spent in the copy but not marked as spent here.");
+        msgParams.second = CClientUIInterface::MSG_ERROR;
+        break;
+    // OK and Aborted are included to prevent a compiler warning.
+    case WalletModel::OK:
+    case WalletModel::Aborted:
+    default:
+        return;
+    }
+
+    emit message(tr("Send Coins"), msgParams.first, msgParams.second);
+}
diff --git a/src/qt/sendcoinsdialog.h b/src/qt/sendcoinsdialog.h
index b295b7d837..4e68e26731 100644
--- a/src/qt/sendcoinsdialog.h
+++ b/src/qt/sendcoinsdialog.h
@@ -1,16 +1,17 @@
 #ifndef SENDCOINSDIALOG_H
 #define SENDCOINSDIALOG_H
 
+#include "walletmodel.h"
+
 #include <QDialog>
 #include <QVariant>
+#include <QPair>
 
 namespace Ui {
     class SendCoinsDialog;
 }
-class WalletModel;
 class SendCoinsEntry;
 class SendCoinsRecipient;
-class OptionsModel;
 
 QT_BEGIN_NAMESPACE
 class QUrl;
@@ -48,6 +49,11 @@ private:
     WalletModel *model;
     bool fNewRecipientAllowed;
 
+    // Process WalletModel::SendCoinsReturn and generate a pair consisting
+    // of a message and message flags for use in emit message().
+    // Additional parameter msgArg can be used via .arg(msgArg).
+    void processSendCoinsReturn(const WalletModel::SendCoinsReturn &sendCoinsReturn, const QString &msgArg = QString());
+
 private slots:
     void on_sendButton_clicked();
     void removeEntry(SendCoinsEntry* entry);