qml: Introduce BitcoinAmount

BitcoinAmount is a helper object can be used to manage inputs in
sats or btc.

Author: johnny9

src/Makefile.qt.include

@@ -46,6 +46,7 @@ QT_MOC_CPP = \
   qml/models/moc_walletlistmodel.cpp \
   qml/models/moc_walletqmlmodel.cpp \
   qml/moc_appmode.cpp \
+  qml/moc_bitcoinamount.cpp \
   qml/moc_walletqmlcontroller.cpp \
   qt/moc_addressbookpage.cpp \
   qt/moc_addresstablemodel.cpp \
@@ -130,6 +131,7 @@ BITCOIN_QT_H = \
   qml/models/walletqmlmodel.h \
   qml/appmode.h \
   qml/bitcoin.h \
+  qml/bitcoinamount.h \
   qml/guiconstants.h \
   qml/imageprovider.h \
   qml/util.h \
@@ -310,6 +312,7 @@ BITCOIN_QT_WALLET_CPP = \
 
 BITCOIN_QML_BASE_CPP = \
   qml/bitcoin.cpp \
+  qml/bitcoinamount.cpp \
   qml/components/blockclockdial.cpp \
   qml/controls/linegraph.cpp \
   qml/models/chainmodel.cpp \

src/qml/bitcoin.cpp

@@ -15,6 +15,7 @@
 #include <node/interface_ui.h>
 #include <noui.h>
 #include <qml/appmode.h>
+#include <qml/bitcoinamount.h>
 #ifdef __ANDROID__
 #include <qml/androidnotifier.h>
 #endif
@@ -330,6 +331,7 @@ int QmlGuiMain(int argc, char* argv[])
     qmlRegisterType<BlockClockDial>("org.bitcoincore.qt", 1, 0, "BlockClockDial");
     qmlRegisterType<LineGraph>("org.bitcoincore.qt", 1, 0, "LineGraph");
     qmlRegisterUncreatableType<PeerDetailsModel>("org.bitcoincore.qt", 1, 0, "PeerDetailsModel", "");
+    qmlRegisterType<BitcoinAmount>("org.bitcoincore.qt", 1, 0, "BitcoinAmount");
 
 #ifdef ENABLE_WALLET
     qmlRegisterUncreatableType<WalletQmlModel>("org.bitcoincore.qt", 1, 0, "WalletQmlModel",

src/qml/bitcoinamount.cpp

@@ -0,0 +1,127 @@
+// Copyright (c) 2024 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <qml/bitcoinamount.h>
+
+#include <QRegExp>
+#include <QStringList>
+
+
+BitcoinAmount::BitcoinAmount(QObject *parent) : QObject(parent)
+{
+    m_unit = Unit::BTC;
+}
+
+int BitcoinAmount::decimals(Unit unit)
+{
+    switch (unit) {
+    case Unit::BTC: return 8;
+    case Unit::SAT: return 0;
+    } // no default case, so the compiler can warn about missing cases
+    assert(false);
+}
+
+QString BitcoinAmount::sanitize(const QString &text)
+{
+    QString result = text;
+
+    // Remove any invalid characters
+    result.remove(QRegExp("[^0-9.]"));
+
+    // Ensure only one decimal point
+    QStringList parts = result.split('.');
+    if (parts.size() > 2) {
+        result = parts[0] + "." + parts[1];
+    }
+
+    // Limit decimal places to 8
+    if (parts.size() == 2 && parts[1].length() > 8) {
+        result = parts[0] + "." + parts[1].left(8);
+    }
+
+    return result;
+}
+
+BitcoinAmount::Unit BitcoinAmount::unit() const
+{
+    return m_unit;
+}
+
+void BitcoinAmount::setUnit(const Unit unit)
+{
+    m_unit = unit;
+    Q_EMIT unitChanged();
+}
+
+QString BitcoinAmount::unitLabel() const
+{
+    switch (m_unit) {
+    case Unit::BTC: return "₿";
+    case Unit::SAT: return "Sat";
+    }
+    assert(false);
+}
+
+QString BitcoinAmount::amount() const
+{
+    return m_amount;
+}
+
+void BitcoinAmount::setAmount(const QString& new_amount)
+{
+    m_amount = sanitize(new_amount);
+    Q_EMIT amountChanged();
+}
+
+long long BitcoinAmount::toSatoshis(QString& amount, const Unit unit)
+{
+
+    int num_decimals = decimals(unit);
+
+    QStringList parts = amount.remove(' ').split(".");
+
+    QString whole = parts[0];
+    QString decimals;
+
+    if(parts.size() > 1)
+    {
+        decimals = parts[1];
+    }
+    QString str = whole + decimals.leftJustified(num_decimals, '0', true);
+
+    return str.toLongLong();
+}
+
+QString BitcoinAmount::convert(const QString &amount, Unit unit)
+{
+    if (amount == "") {
+        return amount;
+    }
+
+    QString result = amount;
+    int decimalPosition  = result.indexOf(".");
+
+    if (decimalPosition == -1) {
+        decimalPosition = result.length();
+        result.append(".");
+    }
+
+    if (unit == Unit::BTC) {
+        int numDigitsAfterDecimal = result.length() - decimalPosition - 1;
+        if (numDigitsAfterDecimal < 8) {
+            result.append(QString(8 - numDigitsAfterDecimal, '0'));
+        }
+        result.remove(decimalPosition, 1);
+    } else if (unit == Unit::SAT) {
+        result.remove(decimalPosition, 1);
+        int newDecimalPosition = decimalPosition - 8;
+        if (newDecimalPosition < 1) {
+            result = QString("0").repeated(-newDecimalPosition) + result;
+            newDecimalPosition = 0;
+        }
+        result.insert(newDecimalPosition, ".");
+    }
+
+    return result;
+}

src/qml/bitcoinamount.h

@@ -0,0 +1,52 @@
+// Copyright (c) 2024 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_QML_BITCOINAMOUNT_H
+#define BITCOIN_QML_BITCOINAMOUNT_H
+
+#include <QObject>
+#include <QString>
+#include <qobjectdefs.h>
+
+class BitcoinAmount : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(Unit unit READ unit WRITE setUnit NOTIFY unitChanged)
+    Q_PROPERTY(QString unitLabel READ unitLabel NOTIFY unitChanged)
+    Q_PROPERTY(QString amount READ amount WRITE setAmount NOTIFY amountChanged)
+
+public:
+    enum class Unit {
+        BTC,
+        SAT
+    };
+    Q_ENUM(Unit)
+
+    explicit BitcoinAmount(QObject *parent = nullptr);
+
+    Unit unit() const;
+    void setUnit(Unit unit);
+    QString unitLabel() const;
+    QString amount() const;
+    void setAmount(const QString& new_amount);
+
+public Q_SLOTS:
+    QString sanitize(const QString &text);
+    QString convert(const QString &text, Unit unit);
+
+Q_SIGNALS:
+    void unitChanged();
+    void unitLabelChanged();
+    void amountChanged();
+
+private:
+    long long toSatoshis(QString &amount, const Unit unit);
+    int decimals(Unit unit);
+
+    Unit m_unit;
+    QString m_unitLabel;
+    QString m_amount;
+};
+
+#endif // BITCOIN_QML_BITCOINAMOUNT_H