Add validation to the Send form (address and amount)

src/Makefile.qt.include

@@ -357,6 +357,7 @@ QML_RES_FONTS = \
 
 QML_RES_ICONS = \
   qml/res/icons/add-wallet-dark.png \
+  qml/res/icons/alert-filled.png \
   qml/res/icons/arrow-down.png \
   qml/res/icons/arrow-up.png \
   qml/res/icons/bitcoin-circle.png \

src/qml/bitcoin_qml.qrc

@@ -101,6 +101,7 @@
     </qresource>
     <qresource prefix="/icons">
         <file alias="add-wallet-dark">res/icons/add-wallet-dark.png</file>
+        <file alias="alert-filled">res/icons/alert-filled.png</file>
         <file alias="arrow-down">res/icons/arrow-down.png</file>
         <file alias="arrow-up">res/icons/arrow-up.png</file>
         <file alias="bitcoin-circle">res/icons/bitcoin-circle.png</file>

src/qml/controls/LabeledTextInput.qml

@@ -13,6 +13,8 @@ Item {
     property alias iconSource: icon.source
     property alias customIcon: iconContainer.data
     property alias enabled: input.enabled
+    property alias validator: input.validator
+    property alias maximumLength: input.maximumLength
 
     signal iconClicked
     signal textEdited

src/qml/models/sendrecipient.cpp

@@ -5,10 +5,14 @@
 #include <qml/models/sendrecipient.h>
 
 #include <qml/bitcoinamount.h>
+#include <qml/models/walletqmlmodel.h>
 
-SendRecipient::SendRecipient(QObject* parent)
-    : QObject(parent), m_amount(new BitcoinAmount(this))
+#include <key_io.h>
+
+SendRecipient::SendRecipient(WalletQmlModel* wallet, QObject* parent)
+    : QObject(parent), m_wallet(wallet), m_amount(new BitcoinAmount(this))
 {
+    connect(m_amount, &BitcoinAmount::amountChanged, this, &SendRecipient::validateAmount);
 }
 
 QString SendRecipient::address() const
@@ -21,6 +25,20 @@ void SendRecipient::setAddress(const QString& address)
     if (m_address != address) {
         m_address = address;
         Q_EMIT addressChanged();
+        validateAddress();
+    }
+}
+
+QString SendRecipient::addressError() const
+{
+    return m_addressError;
+}
+
+void SendRecipient::setAddressError(const QString& error)
+{
+    if (m_addressError != error) {
+        m_addressError = error;
+        Q_EMIT addressErrorChanged();
     }
 }
 
@@ -42,6 +60,19 @@ BitcoinAmount* SendRecipient::amount() const
     return m_amount;
 }
 
+QString SendRecipient::amountError() const
+{
+    return m_amountError;
+}
+
+void SendRecipient::setAmountError(const QString& error)
+{
+    if (m_amountError != error) {
+        m_amountError = error;
+        Q_EMIT amountErrorChanged();
+    }
+}
+
 QString SendRecipient::message() const
 {
     return m_message;
@@ -77,3 +108,42 @@ void SendRecipient::clear()
     Q_EMIT messageChanged();
     Q_EMIT amount()->amountChanged();
 }
+
+void SendRecipient::validateAddress()
+{
+    if (!m_address.isEmpty() && !IsValidDestinationString(m_address.toStdString())) {
+        if (IsValidDestinationString(m_address.toStdString(), *CChainParams::Main())) {
+            setAddressError(tr("Address is valid for mainnet, not the current network"));
+        } else if (IsValidDestinationString(m_address.toStdString(), *CChainParams::TestNet())) {
+            setAddressError(tr("Address is valid for testnet, not the current network"));
+        } else {
+            setAddressError(tr("Invalid address format"));
+        }
+    } else {
+        setAddressError("");
+    }
+
+    Q_EMIT isValidChanged();
+}
+
+void SendRecipient::validateAmount()
+{
+    if (m_amount->isSet()) {
+        if (m_amount->satoshi() <= 0) {
+            setAmountError(tr("Amount must be greater than zero"));
+        } else if (m_amount->satoshi() > MAX_MONEY) {
+            setAmountError(tr("Amount exceeds maximum limit of 21,000,000 BTC"));
+        } else if (m_amount->satoshi() > m_wallet->balanceSatoshi()) {
+            setAmountError(tr("Amount exceeds available balance"));
+        } else {
+            setAmountError("");
+        }
+    }
+
+    Q_EMIT isValidChanged();
+}
+
+bool SendRecipient::isValid() const
+{
+    return m_addressError.isEmpty() && m_amountError.isEmpty() && m_amount->satoshi() > 0 && !m_address.isEmpty();
+}

src/qml/models/sendrecipient.h

@@ -10,6 +10,8 @@
 #include <QObject>
 #include <QString>
 
+class WalletQmlModel;
+
 class SendRecipient : public QObject
 {
     Q_OBJECT
@@ -18,17 +20,25 @@ class SendRecipient : public QObject
     Q_PROPERTY(QString message READ message WRITE setMessage NOTIFY messageChanged)
     Q_PROPERTY(BitcoinAmount* amount READ amount CONSTANT)
 
+    Q_PROPERTY(QString addressError READ addressError NOTIFY addressErrorChanged)
+    Q_PROPERTY(QString amountError READ amountError NOTIFY amountErrorChanged)
+    Q_PROPERTY(bool isValid READ isValid NOTIFY isValidChanged)
+
 public:
-    explicit SendRecipient(QObject* parent = nullptr);
+    explicit SendRecipient(WalletQmlModel* wallet, QObject* parent = nullptr);
 
     QString address() const;
     void setAddress(const QString& address);
+    QString addressError() const;
+    void setAddressError(const QString& error);
 
     QString label() const;
     void setLabel(const QString& label);
 
     BitcoinAmount* amount() const;
     void setAmount(const QString& amount);
+    QString amountError() const;
+    void setAmountError(const QString& error);
 
     QString message() const;
     void setMessage(const QString& message);
@@ -37,18 +47,29 @@ class SendRecipient : public QObject
 
     bool subtractFeeFromAmount() const;
 
+    bool isValid() const;
+
     Q_INVOKABLE void clear();
 
 Q_SIGNALS:
     void addressChanged();
+    void addressErrorChanged();
+    void amountErrorChanged();
     void labelChanged();
     void messageChanged();
+    void isValidChanged();
 
 private:
+    void validateAddress();
+    void validateAmount();
+
+    const WalletQmlModel* m_wallet;
     QString m_address{""};
+    QString m_addressError{""};
     QString m_label{""};
     QString m_message{""};
     BitcoinAmount* m_amount;
+    QString m_amountError{""};
     bool m_subtractFeeFromAmount{false};
 };
 

src/qml/models/sendrecipientslistmodel.cpp

@@ -3,13 +3,15 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <qml/models/sendrecipientslistmodel.h>
+#include <qml/models/walletqmlmodel.h>
 
 #include <qml/models/sendrecipient.h>
 
 SendRecipientsListModel::SendRecipientsListModel(QObject* parent)
     : QAbstractListModel(parent)
 {
-    auto* recipient = new SendRecipient(this);
+    m_wallet = qobject_cast<WalletQmlModel*>(parent);
+    auto* recipient = new SendRecipient(m_wallet, this);
     connect(recipient->amount(), &BitcoinAmount::amountChanged,
             this, &SendRecipientsListModel::updateTotalAmount);
     m_recipients.append(recipient);
@@ -50,7 +52,7 @@ void SendRecipientsListModel::add()
 {
     const int row = m_recipients.size();
     beginInsertRows(QModelIndex(), row, row);
-    auto* recipient = new SendRecipient(this);
+    auto* recipient = new SendRecipient(m_wallet, this);
     connect(recipient->amount(), &BitcoinAmount::amountChanged,
             this, &SendRecipientsListModel::updateTotalAmount);
     if (m_recipients.size() > 0) {
@@ -137,7 +139,7 @@ void SendRecipientsListModel::clear()
     m_current = 0;
     m_totalAmount = 0;
 
-    auto* recipient = new SendRecipient(this);
+    auto* recipient = new SendRecipient(m_wallet, this);
     connect(recipient->amount(), &BitcoinAmount::amountChanged,
             this, &SendRecipientsListModel::updateTotalAmount);
     m_recipients.append(recipient);

src/qml/models/sendrecipientslistmodel.h

@@ -5,11 +5,10 @@
 #ifndef BITCOIN_QML_MODELS_SENDRECIPIENTSLISTMODEL_H
 #define BITCOIN_QML_MODELS_SENDRECIPIENTSLISTMODEL_H
 
-#include <qml/models/sendrecipient.h>
-
 #include <QAbstractListModel>
-#include <QList>
-#include <qobjectdefs.h>
+
+class SendRecipient;
+class WalletQmlModel;
 
 class SendRecipientsListModel : public QAbstractListModel
 {
@@ -58,6 +57,7 @@ class SendRecipientsListModel : public QAbstractListModel
 private:
     void updateTotalAmount();
 
+    WalletQmlModel* m_wallet;
     QList<SendRecipient*> m_recipients;
     int m_current{0};
     qint64 m_totalAmount{0};

src/qml/models/walletqmlmodel.cpp

@@ -55,6 +55,14 @@ QString WalletQmlModel::balance() const
     return BitcoinUnits::format(BitcoinUnits::Unit::BTC, m_wallet->getBalance());
 }
 
+CAmount WalletQmlModel::balanceSatoshi() const
+{
+    if (!m_wallet) {
+        return 0;
+    }
+    return m_wallet->getBalance();
+}
+
 QString WalletQmlModel::name() const
 {
     if (!m_wallet) {

src/qml/models/walletqmlmodel.h

@@ -5,20 +5,21 @@
 #ifndef BITCOIN_QML_MODELS_WALLETQMLMODEL_H
 #define BITCOIN_QML_MODELS_WALLETQMLMODEL_H
 
-#include <interfaces/handler.h>
-#include <interfaces/wallet.h>
 #include <qml/models/activitylistmodel.h>
 #include <qml/models/coinslistmodel.h>
 #include <qml/models/sendrecipient.h>
 #include <qml/models/sendrecipientslistmodel.h>
 #include <qml/models/walletqmlmodeltransaction.h>
+
+#include <consensus/amount.h>
+#include <interfaces/handler.h>
+#include <interfaces/wallet.h>
 #include <wallet/coincontrol.h>
 
-#include <QObject>
 #include <memory>
 #include <vector>
 
-class ActivityListModel;
+#include <QObject>
 
 class WalletQmlModel : public QObject
 {
@@ -39,6 +40,8 @@ class WalletQmlModel : public QObject
 
     QString name() const;
     QString balance() const;
+    CAmount balanceSatoshi() const;
+
     ActivityListModel* activityListModel() const { return m_activity_list_model; }
     CoinsListModel* coinsListModel() const { return m_coins_list_model; }
     SendRecipientsListModel* sendRecipientList() const { return m_send_recipients; }

src/qml/models/walletqmlmodeltransaction.cpp

@@ -4,6 +4,9 @@
 
 #include <qml/models/walletqmlmodeltransaction.h>
 
+#include <qml/models/sendrecipient.h>
+#include <qml/models/sendrecipientslistmodel.h>
+
 #include <policy/policy.h>
 
 WalletQmlModelTransaction::WalletQmlModelTransaction(const SendRecipientsListModel* recipient, QObject* parent)