refactor: consolidate font picking into one dialog (#6531)

Instead of three separate dropdowns in the setting dialog, we now expose a single label + button combo for modifying the font.
When the button is pressed, we open a custom font dialog allowing the user to customize the font family, font size, and font weight.

Reviewed-by: nerix <nerixdev@outlook.de>
Reviewed-by: pajlada <rasmus.karlsson@pajlada.com>

src/widgets/helper/FontSettingWidget.cpp

@@ -0,0 +1,69 @@
+#include "widgets/helper/FontSettingWidget.hpp"
+
+#include "Application.hpp"
+#include "singletons/Fonts.hpp"
+#include "singletons/Settings.hpp"
+#include "widgets/dialogs/font/FontSettingDialog.hpp"
+
+#include <QFont>
+#include <QHBoxLayout>
+#include <QString>
+#include <QToolButton>
+
+namespace chatterino {
+
+FontSettingWidget::FontSettingWidget(QStringSetting &family, IntSetting &size,
+                                     IntSetting &weight, QWidget *parent)
+    : QWidget(parent)
+    , familySetting(family)
+    , sizeSetting(size)
+    , weightSetting(weight)
+    , currentLabel(new QLabel)
+    , listener([this] {
+        this->updateCurrentLabel();
+    })
+{
+    auto *layout = new QHBoxLayout;
+    auto *button = new QToolButton;
+
+    this->setLayout(layout);
+    this->updateCurrentLabel();
+
+    this->listener.add(getApp()->getFonts()->fontChanged);
+
+    layout->addWidget(new QLabel("Font:"));
+    layout->addStretch(1);
+    layout->addWidget(this->currentLabel);
+    layout->addWidget(button);
+    layout->setContentsMargins(0, 0, 0, 0);
+
+    button->setIcon(QIcon(":/buttons/edit.svg"));
+
+    QObject::connect(button, &QToolButton::clicked, this,
+                     &FontSettingWidget::showDialog);
+}
+
+void FontSettingWidget::updateCurrentLabel()
+{
+    QFont font = getApp()->getFonts()->getFont(FontStyle::ChatMedium, 1);
+    QString family = font.family();
+    QString ptSize = QString::number(font.pointSize());
+    this->currentLabel->setText(family + ", " + ptSize + "pt");
+}
+
+void FontSettingWidget::showDialog()
+{
+    if (!this->dialog)
+    {
+        this->dialog = new FontSettingDialog(
+            this->familySetting, this->sizeSetting, this->weightSetting, this);
+
+        QObject::connect(this->dialog, &QObject::destroyed, [this] {
+            this->dialog = nullptr;
+        });
+    }
+
+    this->dialog->show();
+}
+
+}  // namespace chatterino

src/widgets/helper/FontSettingWidget.hpp

@@ -0,0 +1,35 @@
+#pragma once
+
+#include "common/ChatterinoSetting.hpp"
+#include "util/SignalListener.hpp"
+
+#include <QLabel>
+#include <QWidget>
+
+namespace chatterino {
+
+class FontSettingDialog;
+
+/// FontSettingWidget includes a label showing the current font and its size, with a button
+/// that opens a FontSettingDialog
+class FontSettingWidget : public QWidget
+{
+public:
+    FontSettingWidget(QStringSetting &family, IntSetting &size,
+                      IntSetting &weight, QWidget *parent = nullptr);
+
+private:
+    void updateCurrentLabel();
+    void showDialog();
+
+    FontSettingDialog *dialog = nullptr;
+
+    QStringSetting &familySetting;
+    IntSetting &sizeSetting;
+    IntSetting &weightSetting;
+
+    QLabel *currentLabel;
+    SignalListener listener;
+};
+
+}  // namespace chatterino