qml: only use QEAmount container instead of javascript/qml (q(u))int(64)

Using javascript or QML `int` type is a long-standing issue, as there is not enough range to express millisats or even sats.
A short summary of the issues:
- integers in javascript context have a max range of +/- 2^54-1, which allows 21M BTC expressed in sats, but not in msats.
- QML `int` properties have a max range of +/- 2^31-1, which only allows 21 BTC expressed in sats, 21 mBTC expressed in msats
- `int` parameters declared in the `pyqtProperty` and `pyqtSlot` decorators have a max range of 2^31-1,
although this is somewhat alleviated in the QML->Python direction by using `q(u)int64`. Returning a `q(u)int64` does not
work around the `int` limitation

In most of the QML code, `QEAmount` is already used for storing and passing around BTC values.
The only exception is where amounts are compared (e.g. invoice amount < available balance etc),
so the `<`, `>`, `<=`, `>=` and `!=` operators, and where these operators are implied, like `Math.min()` and `Math.max()`

This commit delegates these operators to python scope.

Author: accumulator

electrum/gui/qml/components/BalanceDetails.qml

@@ -214,7 +214,7 @@ Pane {
                 Layout.preferredWidth: 1
                 text: qsTr('Lightning swap');
                 visible: Daemon.currentWallet.isLightning
-                enabled: Daemon.currentWallet.lightningCanSend.satsInt > 0 || Daemon.currentWallet.lightningCanReceive.satInt > 0
+                enabled: !Daemon.currentWallet.lightningCanSend.isEmpty || !Daemon.currentWallet.lightningCanReceive.isEmpty
                 icon.source: Qt.resolvedUrl('../../icons/update.png')
                 onClicked: app.startSwap()
             }
@@ -224,7 +224,7 @@ Pane {
                 Layout.preferredWidth: 1
                 text: qsTr('Open Channel')
                 visible: Daemon.currentWallet.isLightning
-                enabled: Daemon.currentWallet.confirmedBalance.satsInt > 0
+                enabled: !Daemon.currentWallet.confirmedBalance.isEmpty
                 onClicked: {
                     var dialog = openChannelDialog.createObject(rootItem)
                     dialog.open()

electrum/gui/qml/components/Channels.qml

@@ -125,16 +125,16 @@ Pane {
                 Layout.fillWidth: true
                 Layout.preferredWidth: 1
                 text: qsTr('Swap');
-                enabled: Daemon.currentWallet.lightningCanSend.satsInt > 0 ||
-                    (Daemon.currentWallet.lightningCanReceive.satsInt > 0 && Daemon.currentWallet.confirmedBalance.satsInt > 0)
+                enabled: !Daemon.currentWallet.lightningCanSend.isEmpty ||
+                    (!Daemon.currentWallet.lightningCanReceive.isEmpty && !Daemon.currentWallet.confirmedBalance.isEmpty)
                 icon.source: Qt.resolvedUrl('../../icons/update.png')
                 onClicked: app.startSwap()
             }
 
             FlatButton {
                 Layout.fillWidth: true
                 Layout.preferredWidth: 1
-                enabled: Daemon.currentWallet.canHaveLightning && Daemon.currentWallet.confirmedBalance.satsInt > 0
+                enabled: Daemon.currentWallet.canHaveLightning && !Daemon.currentWallet.confirmedBalance.isEmpty
                 text: qsTr('Open Channel')
                 onClicked: {
                     if (Daemon.currentWallet.channelModel.count == 0) {

electrum/gui/qml/components/InvoiceDialog.qml

@@ -229,16 +229,16 @@ ElDialog {
                                 color: readOnly
                                     ? Material.accentColor
                                     : Material.foreground
-                                onTextAsSatsChanged: {
+                                onValueChanged: {
                                     if (!amountMax.checked)
                                         invoice.amountOverride.copyFrom(textAsSats)
                                 }
                                 Connections {
                                     target: invoice.amountOverride
                                     function onValueChanged() {
-                                        console.log('amountOverride valueChanged, sats=' + invoice.amountOverride.satsInt)
+                                        console.log('amountOverride valueChanged, sats=' + invoice.amountOverride.satsStr)
                                         if (amountMax.checked)  // amountOverride updated by max amount estimate
-                                            amountBtc.text = Config.formatSatsForEditing(invoice.amountOverride.satsInt)
+                                            amountBtc.text = Config.formatSatsForEditing(invoice.amountOverride)
                                     }
                                 }
                             }

electrum/gui/qml/components/LightningPaymentDetails.qml

@@ -52,7 +52,7 @@ Pane {
             }
 
             Label {
-                text: lnpaymentdetails.amount.msatsInt > 0
+                text: lnpaymentdetails.amount.positive
                         ? qsTr('Amount received')
                         : qsTr('Amount sent')
                 color: Material.accentColor
@@ -64,13 +64,13 @@ Pane {
             }
 
             Label {
-                visible: lnpaymentdetails.amount.msatsInt < 0
+                visible: !lnpaymentdetails.amount.positive
                 text: qsTr('Transaction fee')
                 color: Material.accentColor
             }
 
             FormattedAmount {
-                visible: lnpaymentdetails.amount.msatsInt < 0
+                visible: !lnpaymentdetails.amount.positive
                 amount: lnpaymentdetails.fee
                 timestamp: lnpaymentdetails.timestamp
             }

electrum/gui/qml/components/LnurlPayRequestDialog.qml

@@ -19,10 +19,14 @@ ElDialog {
     needsSystemBarPadding: false
 
     property bool commentValid: comment.text.length <= invoiceParser.lnurlData['comment_allowed']
-    property bool amountValid: amountBtc.textAsSats.msatsInt >= parseInt(invoiceParser.lnurlData['min_sendable_msat'])
-        && amountBtc.textAsSats.msatsInt <= parseInt(invoiceParser.lnurlData['max_sendable_msat'])
+    property bool amountValid: false
     property bool valid: commentValid && amountValid
 
+    function isValidAmount() {
+        return amountBtc.textAsSats.gte(invoiceParser.lnurlData['min_sendable_msat'])
+            && amountBtc.textAsSats.lte(invoiceParser.lnurlData['max_sendable_msat'])
+    }
+
     ColumnLayout {
         width: parent.width
 
@@ -41,7 +45,7 @@ ElDialog {
                 Layout.columnSpan: 2
                 Layout.fillWidth: true
                 compact: true
-                visible: invoiceParser.lnurlData['min_sendable_msat'] != invoiceParser.lnurlData['max_sendable_msat']
+                visible: !invoiceParser.lnurlData['min_sendable_msat'].eq(invoiceParser.lnurlData['max_sendable_msat'])
                 text: qsTr('Amount must be between %1 and %2 %3')
                     .arg(Config.formatMilliSats(invoiceParser.lnurlData['min_sendable_msat']))
                     .arg(Config.formatMilliSats(invoiceParser.lnurlData['max_sendable_msat']))
@@ -77,12 +81,13 @@ ElDialog {
                     id: amountBtc
                     Layout.preferredWidth: rootLayout.width /3
                     text: Config.formatMilliSatsForEditing(invoiceParser.lnurlData['min_sendable_msat'])
-                    enabled: invoiceParser.lnurlData['min_sendable_msat'] != invoiceParser.lnurlData['max_sendable_msat']
+                    enabled: !invoiceParser.lnurlData['min_sendable_msat'].eq(invoiceParser.lnurlData['max_sendable_msat'])
                     color: Material.foreground // override gray-out on disabled
                     fiatfield: amountFiat
                     msatPrecision: true
-                    onTextAsSatsChanged: {
+                    onValueChanged: {
                         invoiceParser.amountOverride = textAsSats
+                        dialog.amountValid = isValidAmount()
                     }
                 }
                 Label {

electrum/gui/qml/components/LnurlWithdrawRequestDialog.qml

@@ -15,25 +15,26 @@ ElDialog {
 
     property Wallet wallet: Daemon.currentWallet
     property RequestDetails requestDetails
+    property Amount onemsat: Amount { Component.onCompleted: { msatsInt = 1 } }
 
     padding: 0
     needsSystemBarPadding: false
 
-    property int walletCanReceive: 0
-    property int providerMinWithdrawable: parseInt(requestDetails.lnurlData['min_withdrawable_msat'])
-    property int providerMaxWithdrawable: parseInt(requestDetails.lnurlData['max_withdrawable_msat'])
-    property int effectiveMinWithdrawable: Math.max(providerMinWithdrawable, 1)
-    property int effectiveMaxWithdrawable: Math.min(providerMaxWithdrawable, walletCanReceive)
-    property bool insufficientLiquidity: effectiveMinWithdrawable > walletCanReceive
-    property bool liquidityWarning: providerMaxWithdrawable > walletCanReceive
+    property var walletCanReceive: Amount {}
+    property var providerMinWithdrawable: requestDetails.lnurlData['min_withdrawable_msat']
+    property var providerMaxWithdrawable: requestDetails.lnurlData['max_withdrawable_msat']
+    property var effectiveMinWithdrawable: onemsat.max(providerMinWithdrawable, onemsat)
+    property var effectiveMaxWithdrawable: onemsat.min(providerMaxWithdrawable, walletCanReceive)
+    property bool insufficientLiquidity: effectiveMinWithdrawable.gt(walletCanReceive)
+    property bool liquidityWarning: providerMaxWithdrawable.gt(walletCanReceive)
 
     property bool amountValid: !dialog.insufficientLiquidity &&
-        amountBtc.textAsSats.msatsInt >= dialog.effectiveMinWithdrawable &&
-        amountBtc.textAsSats.msatsInt <= dialog.effectiveMaxWithdrawable
+        amountBtc.textAsSats.gte(dialog.effectiveMinWithdrawable) &&
+        amountBtc.textAsSats.lte(dialog.effectiveMaxWithdrawable)
     property bool valid: amountValid
 
     Component.onCompleted: {
-        dialog.walletCanReceive = wallet.lightningCanReceive.msatsInt
+        dialog.walletCanReceive.copyFrom(wallet.lightningCanReceive)
     }
 
     Connections {
@@ -43,7 +44,7 @@ ElDialog {
             if (!requestDetails.busy) {
                 // don't assign while busy to prevent the view from changing while receiving
                 // the incoming payment
-                dialog.walletCanReceive = wallet.lightningCanReceive.msatsInt
+                dialog.walletCanReceive.copyFrom(wallet.lightningCanReceive)
             }
         }
     }
@@ -83,9 +84,9 @@ ElDialog {
                 compact: true
                 visible: !dialog.insufficientLiquidity && dialog.providerMinWithdrawable != dialog.providerMaxWithdrawable
                 text: qsTr('Amount must be between %1 and %2 %3')
-                .arg(Config.formatMilliSats(dialog.effectiveMinWithdrawable))
-                .arg(Config.formatMilliSats(dialog.effectiveMaxWithdrawable))
-                .arg(Config.baseUnit)
+                        .arg(Config.formatMilliSats(dialog.effectiveMinWithdrawable))
+                        .arg(Config.formatMilliSats(dialog.effectiveMaxWithdrawable))
+                        .arg(Config.baseUnit)
             }
 
             InfoTextArea {
@@ -132,7 +133,7 @@ ElDialog {
                     id: amountBtc
                     Layout.preferredWidth: rootLayout.width / 3
                     text: Config.formatMilliSatsForEditing(dialog.effectiveMaxWithdrawable)
-                    enabled: !dialog.insufficientLiquidity && (dialog.providerMinWithdrawable != dialog.providerMaxWithdrawable)
+                    enabled: !dialog.insufficientLiquidity && !(dialog.providerMinWithdrawable.eq(dialog.providerMaxWithdrawable))
                     color: Material.foreground // override gray-out on disabled
                     fiatfield: amountFiat
                     msatPrecision: true
@@ -151,7 +152,7 @@ ElDialog {
                     id: amountFiat
                     Layout.preferredWidth: rootLayout.width / 3
                     btcfield: amountBtc
-                    enabled: !dialog.insufficientLiquidity && (dialog.providerMinWithdrawable != dialog.providerMaxWithdrawable)
+                    enabled: !dialog.insufficientLiquidity && !(dialog.providerMinWithdrawable.eq(dialog.providerMaxWithdrawable))
                     color: Material.foreground
                 }
                 Label {
@@ -168,8 +169,7 @@ ElDialog {
             icon.source: '../../icons/confirmed.png'
             enabled: valid && !requestDetails.busy
             onClicked: {
-                var msatsAmount = amountBtc.textAsSats.msatsInt;
-                requestDetails.lnurlRequestWithdrawal(msatsAmount);
+                requestDetails.lnurlRequestWithdrawal(amountBtc.textAsSats);
                 dialog.close();
             }
         }

electrum/gui/qml/components/OpenChannelDialog.qml

@@ -170,7 +170,7 @@ ElDialog {
                     id: amountBtc
                     fiatfield: amountFiat
                     Layout.preferredWidth: amountFontMetrics.advanceWidth('0') * 14 + leftPadding + rightPadding
-                    onTextAsSatsChanged: {
+                    onValueChanged: {
                         if (!is_max.checked)
                             channelopener.amount = amountBtc.textAsSats
                     }
@@ -183,7 +183,7 @@ ElDialog {
                         target: channelopener.amount
                         function onValueChanged() {
                             if (is_max.checked)  // amount updated by max amount estimate
-                                amountBtc.text = Config.formatSatsForEditing(channelopener.amount.satsInt)
+                                amountBtc.text = Config.formatSatsForEditing(channelopener.amount)
                         }
                     }
                 }

electrum/gui/qml/components/ReceiveDetailsDialog.qml

@@ -110,17 +110,16 @@ ElDialog {
             FlatButton {
                 Layout.fillWidth: true
                 Layout.preferredWidth: 1
-                enabled: Daemon.currentWallet.isLightning && (Daemon.currentWallet.lightningCanReceive.msatsInt
-                            > amountBtc.textAsSats.msatsInt || Daemon.currentWallet.canGetZeroconfChannel)
+                enabled: Daemon.currentWallet.isLightning && (Daemon.currentWallet.lightningCanReceive.gt(amountBtc.textAsSats)
+                    || Daemon.currentWallet.canGetZeroconfChannel)
                 text: qsTr('Lightning')
                 icon.source: '../../icons/lightning.png'
                 onClicked: {
-                    if (Daemon.currentWallet.lightningCanReceive.msatsInt > amountBtc.textAsSats.msatsInt) {
+                    if (Daemon.currentWallet.lightningCanReceive.gt(amountBtc.textAsSats)) {
                         // can receive on existing channel
                         dialog.isLightning = true
                         doAccept()
-                    } else if (Daemon.currentWallet.canGetZeroconfChannel && amountBtc.textAsSats.msatsInt
-                                >= Daemon.currentWallet.minChannelFunding.msatsInt) {
+                    } else if (Daemon.currentWallet.canGetZeroconfChannel && amountBtc.textAsSats.gte(Daemon.currentWallet.minChannelFunding)) {
                         // ask for confirmation of zeroconf channel to prevent fee surprise
                         var confirmdialog = app.messageDialog.createObject(dialog, {
                             title: qsTr('Confirm just-in-time channel'),
@@ -140,7 +139,7 @@ ElDialog {
                             title: qsTr("Amount too low"),
                             text: [qsTr("You don't have channels with enough inbound liquidity to receive this payment."),
                                    qsTr("Request at least %1 to open a channel just-in-time.").arg(
-                                       Config.formatSats(Daemon.currentWallet.minChannelFunding.satsInt, true))].join(' ')
+                                       Config.formatSats(Daemon.currentWallet.minChannelFunding, true))].join(' ')
                         })
                         confirmdialog.open()
                     }

electrum/gui/qml/components/TxDetails.qml

@@ -106,8 +106,8 @@ Pane {
                     Label {
                         Layout.preferredWidth: 1
                         Layout.fillWidth: true
-                        visible: !txdetails.isUnrelated && txdetails.amount.satsInt != 0
-                        text: txdetails.amount.satsInt > 0
+                        visible: !txdetails.isUnrelated && !txdetails.amount.isEmpty
+                        text: txdetails.amount.positive
                                 ? qsTr('Amount received onchain')
                                 : qsTr('Amount sent onchain')
                         color: Material.accentColor
@@ -117,23 +117,23 @@ Pane {
                     FormattedAmount {
                         Layout.preferredWidth: 1
                         Layout.fillWidth: true
-                        visible: !txdetails.isUnrelated && txdetails.amount.satsInt != 0
+                        visible: !txdetails.isUnrelated && !txdetails.amount.isEmpty
                         amount: txdetails.amount
                         timestamp: txdetails.timestamp
                     }
 
                     Label {
                         Layout.fillWidth: true
-                        visible: !txdetails.isUnrelated && txdetails.lnAmount.satsInt != 0
-                        text: txdetails.lnAmount.satsInt > 0
+                        visible: !txdetails.isUnrelated && !txdetails.lnAmount.isEmpty
+                        text: txdetails.lnAmount.positive
                                 ? qsTr('Amount received in channels')
                                 : qsTr('Amount withdrawn from channels')
                         color: Material.accentColor
                         wrapMode: Text.Wrap
                     }
 
                     FormattedAmount {
-                        visible: !txdetails.isUnrelated && txdetails.lnAmount.satsInt != 0
+                        visible: !txdetails.isUnrelated && !txdetails.lnAmount.isEmpty
                         Layout.preferredWidth: 1
                         Layout.fillWidth: true
                         amount: txdetails.lnAmount.isEmpty ? txdetails.amount : txdetails.lnAmount

electrum/gui/qml/components/WalletMainView.qml

@@ -540,9 +540,9 @@ Item {
                 if (invoice.invoiceType == Invoice.LightningInvoice && invoice.address) {
                     // ln invoice with fallback
                     var amountToSend = invoice.amountOverride.isEmpty
-                        ? invoice.amount.satsInt
-                        : invoice.amountOverride.satsInt
-                    if (amountToSend > Daemon.currentWallet.lightningCanSend.satsInt) {
+                        ? invoice.amount
+                        : invoice.amountOverride
+                    if (amountToSend.gt(Daemon.currentWallet.lightningCanSend)) {
                         lninvoiceButPayOnchain = true
                     }
                 }