fix: 150% and 200% zoom levels prevent the user from logging in

- TLDR: we were scaling twice, resulting in ginourmous pixel values

The long story:
- since Qt treats the various scale factors in a multiplicative way (see
https://www.qt.io/blog/2016/01/26/high-dpi-support-in-qt-5-6 for
explanation) and there's no way to get the screen's baseline scale
factor programatically, we also have to export `QT_SCREEN_SCALE_FACTORS`
to something that's not equal to `0` or `1` to force the monitor scale
factor to `100%` and then compensate for it when exporting our own scale
value using `QT_SCALE_FACTOR`
- make the UI slider values go in `25%` steps, allowing for more fine
grained control; with `100%` we fallback to the Qt's native handling of
highdpi
- raised the maximum to `300%` since on highres displays, one wouldn't
be able to go over the implicit maximum of `200%` (due to the internal
scaling being 2x)
- scale our main window's minimum width/height so that we don't overflow
the monitor's available space
- modernize the `ConfirmAppRestartModal` to use `StatusDialog`
- use the new `Utils.restartApplication()` when changing the UI language
as well
- remove some dead code

In the (very) long term, we should take a different approach of scaling
our app independently of Qt, just taking the monitor
`Screen.devicePixelRatio` into account, similar to what other apps like
Telegram do

Fixes #13484

ui/app/AppLayouts/Profile/popups/ConfirmAppRestartModal.qml

@@ -1,44 +1,26 @@
-import QtQuick 2.13
-import QtQuick.Controls 2.13
-import QtQuick.Layouts 1.13
-
-import utils 1.0
+import QtQuick 2.15
+import QtQml.Models 2.15
 
 import StatusQ.Controls 0.1
+import StatusQ.Core 0.1
+import StatusQ.Popups.Dialog 0.1
 
-import shared 1.0
-import shared.panels 1.0
-import shared.popups 1.0
-
-// TODO: replace with StatusModal
-ModalPopup {
-    height: 237
-    width: 400
-
-    property Popup parentPopup
-
+StatusDialog {
+    id: root
     title: qsTr("Application Restart")
 
-    StyledText {
+    contentItem: StatusBaseText {
         text: qsTr("Please restart the application to apply the changes.")
-        font.pixelSize: 15
-        anchors.left: parent.left
-        anchors.right: parent.right
         wrapMode: Text.WordWrap
     }
 
-    footer: Item {
-        id: footerContainer
-        width: parent.width
-        height: children[0].height
-
-        StatusButton {
-            anchors.right: parent.right
-            anchors.rightMargin: Style.current.smallPadding
-            type: StatusBaseButton.Type.Danger
-            text: qsTr("Restart")
-            anchors.bottom: parent.bottom
-            onClicked: Utils.restartApplication();
+    footer: StatusDialogFooter {
+        rightButtons: ObjectModel {
+            StatusButton {
+                type: StatusBaseButton.Type.Danger
+                text: qsTr("Restart")
+                onClicked: root.accepted()
+            }
         }
     }
 }

ui/app/AppLayouts/Profile/views/AppearanceView.qml

@@ -1,7 +1,8 @@
-import QtQuick 2.13
-import QtQuick.Controls 2.13
-import QtQuick.Layouts 1.13
-import QtQuick.Controls.Universal 2.12
+import QtQuick 2.15
+import QtQuick.Controls 2.15
+import QtQuick.Layouts 1.15
+import QtQuick.Window 2.15
+import QtQuick.Controls.Universal 2.15
 
 import utils 1.0
 import shared 1.0
@@ -37,20 +38,29 @@ SettingsContentBase {
         appearanceView.updateFontSize(localAccountSensitiveSettings.fontSize)
     }
 
+    readonly property var priv: QtObject {
+        id: priv
+
+        readonly property real savedDpr: {
+            const scaleFactorStr = appearanceView.appearanceStore.readTextFile(uiScaleFilePath)
+            if (scaleFactorStr === "") {
+                return 1
+            }
+            const scaleFactor = parseFloat(scaleFactorStr)
+            if (isNaN(scaleFactor)) {
+                return 1
+            }
+            return scaleFactor
+        }
+    }
+
     Item {
         id: appearanceContainer
         anchors.left: !!parent ? parent.left : undefined
+        anchors.leftMargin: Style.current.padding
         width: appearanceView.contentWidth - 2 * Style.current.padding
         height: childrenRect.height
 
-        ButtonGroup {
-            id: chatModeSetting
-        }
-
-        ButtonGroup {
-            id: appearanceSetting
-        }
-
         Rectangle {
             id: preview
             anchors.top: parent.top
@@ -128,41 +138,34 @@ SettingsContentBase {
 
         StatusQ.StatusLabeledSlider {
             id: zoomSlider
-            readonly property int initialValue: {
-                let scaleFactorStr = appearanceView.appearanceStore.readTextFile(uiScaleFilePath)
-                if (scaleFactorStr === "") {
-                    return 100
-                }
-                let scaleFactor = parseFloat(scaleFactorStr)
-                if (isNaN(scaleFactor)) {
-                    return 100
-                }
-                return scaleFactor * 100
-            }
+
+            readonly property int initialValue: priv.savedDpr * 100
+            readonly property bool dirty: value !== initialValue
+
             anchors.top: labelZoom.bottom
             anchors.topMargin: Style.current.padding
             width: parent.width
             from: 50
-            to: 200
-            stepSize: 50
-            model: [ qsTr("50%"), qsTr("100%"), qsTr("150%"), qsTr("200%") ]
+            to: 300
+            stepSize: 25
+            model: [ qsTr("50%"), qsTr("75%"), qsTr("100%"), qsTr("125%"), qsTr("150%"), qsTr("175%"), qsTr("200%"),
+                qsTr("225%"), qsTr("250%"), qsTr("275%"), qsTr("300%")]
             value: initialValue
-            onValueChanged: {
-                if (value !== initialValue) {
-                    appearanceView.appearanceStore.writeTextFile(uiScaleFilePath, value / 100.0)
-                }
+            onMoved: {
+                const uiScale = zoomSlider.value === 100 ? "" // reset to native highdpi
+                                                         : zoomSlider.value / 100.0
+                appearanceView.appearanceStore.writeTextFile(uiScaleFilePath, uiScale)
             }
             onPressedChanged: {
-                if (!pressed && value !== initialValue) {
+                if (!pressed && dirty) {
                     confirmAppRestartModal.open()
                 }
             }
 
             ConfirmAppRestartModal {
                 id: confirmAppRestartModal
-                onClosed: {
-                    zoomSlider.value = zoomSlider.initialValue
-                }
+                onAccepted: Utils.restartApplication();
+                onClosed: zoomSlider.value = zoomSlider.initialValue
             }
         }
 

ui/app/AppLayouts/Profile/views/LanguageView.qml

@@ -189,13 +189,12 @@ SettingsContentBase {
             sourceComponent: ConfirmationDialog {
                 headerSettings.title: qsTr("Change language")
                 confirmationText: qsTr("Display language has been changed. You must restart the application for changes to take effect.")
-                confirmButtonLabel: qsTr("Close the app now")
+                confirmButtonLabel: qsTr("Restart")
                 onConfirmButtonClicked: {
                     languageConfirmationDialog.active = false
-                    Qt.quit()
+                    Utils.restartApplication()
                 }
             }
         }
     }
 }
-

ui/main.qml

@@ -1,11 +1,11 @@
-import QtQuick 2.13
-import QtQuick.Controls 2.13
-import QtQuick.Layouts 1.13
+import QtQuick 2.15
+import QtQuick.Controls 2.15
+import QtQuick.Layouts 1.15
 import Qt.labs.platform 1.1
-import Qt.labs.settings 1.0
-import QtQuick.Window 2.12
-import QtQml 2.13
-import QtQuick.Controls.Universal 2.12
+import Qt.labs.settings 1.1
+import QtQuick.Window 2.15
+import QtQml 2.15
+import QtQuick.Controls.Universal 2.15
 
 import utils 1.0
 import shared 1.0
@@ -25,8 +25,8 @@ StatusWindow {
 
     id: applicationWindow
     objectName: "mainWindow"
-    minimumWidth: 1200
-    minimumHeight: 680
+    minimumWidth: 1200 / Screen.devicePixelRatio
+    minimumHeight: 680 / Screen.devicePixelRatio
     color: Style.current.background
     title: {
         // Set application settings

vendor/DOtherSide/lib/src/DOtherSide.cpp

@@ -166,8 +166,18 @@ void dos_qguiapplication_enable_hdpi(const char *uiScaleFilePath)
 
     QFile scaleFile(QString::fromUtf8(uiScaleFilePath));
     if (scaleFile.open(QIODevice::ReadOnly)) {
-        const auto scale = scaleFile.readAll();
-        qputenv("QT_SCALE_FACTOR", scale);
+        const auto scaleStr = scaleFile.readAll();
+        bool ok = false;
+        const auto scale = scaleStr.toDouble(&ok);
+        if (ok) {
+            // we want to scale the app on our own
+            qputenv("QT_AUTO_SCREEN_SCALE_FACTOR", "0");
+            // workaround for bug/feature when Qt would bail out if the scale is "1" and revert to DPI based scaling
+            constexpr auto unaryScale = 1.1;
+            qputenv("QT_SCREEN_SCALE_FACTORS", QByteArray::number(unaryScale));
+            // compensate for the workaround above so that we get the desired scale factor
+            qputenv("QT_SCALE_FACTOR", QByteArray::number(scale/unaryScale, 'f', 2));
+        }
     }
 }
 
@@ -373,7 +383,7 @@ void dos_qguiapplication_quit()
 
 void dos_qguiapplication_restart()
 {
-    QProcess::startDetached(QCoreApplication::applicationFilePath());
+    QProcess::startDetached(QCoreApplication::applicationFilePath(), {});
     dos_qguiapplication_quit();
 }