From 05f4dae9e3aa5a9ee9cce11dee3de98bc44c07f6 Mon Sep 17 00:00:00 2001
From: Tio TROM <tio@trom.tf>
Date: Thu, 10 Aug 2023 17:03:39 +0200
Subject: [PATCH] added QT scaling support

---
 bin/periodic/fix-theming | 50 ++++++++++++++++++++++++++++++++++------
 1 file changed, 43 insertions(+), 7 deletions(-)

diff --git a/bin/periodic/fix-theming b/bin/periodic/fix-theming
index 1d6a7ea..889ffc9 100755
--- a/bin/periodic/fix-theming
+++ b/bin/periodic/fix-theming
@@ -3,9 +3,10 @@
 # Exit out if the same script is already running in the background
 pidof -sq -o %PPID -x "$(basename "$0")" && exit
 
-# Set the directory paths
+# Set the directory/file paths
 flatpak_themes_dir="$HOME/.themes"
 flatpak_icons_dir="$HOME/.icons"
+profile="$HOME/.profile"
 
 # Create flatpak icons & themes directories if they don't exist
 mkdir -p "$flatpak_themes_dir" "$flatpak_icons_dir" ||
@@ -25,6 +26,26 @@ xdg_directory_lookup() {
 	done < <(printf '%s:%s\n' "$HOME/.local/share" "$XDG_DATA_DIRS" | tr ':' '\n')
 }
 
+# Function for setting variables in ~/.profile
+profile_set_variable() {
+	# Return if the variable is already set to the correct value
+	grep -xq "\s*export\s\+$1=$2\s*" "$profile" && return
+	# If the variable is set to a different value then remove that line
+	grep -q "^\s*export\s\+$1=" "$profile" && sed -i "/^\s*export\s\+$1=/d" "$profile"
+
+	# Set the variable to the correct value under a comment mentioning this script
+	if grep -xq '\s*#\s*Values set by the fix-theming script\s*' "$profile"; then
+		sed -i "/^\s*#\s*Values set by the fix-theming script\s*$/a export $1=$2" "$profile"
+	elif grep -q '\s' "$profile"; then
+		tail -n1 "$profile" | grep -qx '\s*' && begin='' || begin='\n'
+		printf '%b# Values set by the fix-theming script\nexport %s=%s\n' "$begin" "$1" "$2" >> "$profile"
+	else
+		printf '# Values set by the fix-theming script\nexport %s=%s\n' "$1" "$2" > "$profile"
+	fi
+	# Set variable logout_required to true
+	logout_required='true'
+}
+
 hdpi_theme_fix() {
 	# Get the current window scaling factor (highDPI setting)
 	current_scaling=$(xfconf-query -c xsettings -p /Gdk/WindowScalingFactor)
@@ -33,12 +54,18 @@ hdpi_theme_fix() {
 	# Get the current mouse cursor size
 	cursor_size=$(xfconf-query -c xsettings -p /Gtk/CursorThemeSize)
 
+	unset logout_required
+
 	if [ "$current_scaling" -eq '2' ]; then
-		# Increase mouse cursor size if it's less than 45
-		if [ "$cursor_size" -lt 45 ]; then
+		# Increase mouse cursor size if it's equal to 25
+		if [ "$cursor_size" -eq 25 ]; then
 			xfconf-query -c xsettings -p /Gtk/CursorThemeSize -s '45'
 			notify-send 'Mouse cursor size increased to 45' "Changed to a larger mouse cursor because you've enabled highDPI on your system"
 		fi
+		# Increase scaling for QT apps
+		for var in QT_SCALE_FACTOR QT_AUTO_SCREEN_SCALE_FACTOR QT_ENABLE_HIGHDPI_SCALING; do
+			profile_set_variable "$var" 2
+		done
 		for variant in xhdpi hdpi; do
 			# If this variant of the theme is already enabled then break out of the loop
 			[ "${current_xfwm_theme##*-}" = "$variant" ] && break
@@ -49,16 +76,21 @@ hdpi_theme_fix() {
 			# If this directory exists then change to that theme for XFWM
 			if [ -d "$highDPI_theme_dir" ]; then
 				xfconf-query -c xfwm4 -p /general/theme -n -t string -s "$highDPI_theme"
-				notify-send "XFWM theme changed to $highDPI_theme" "Changed to the highDPI variant of your chosen theme because you've enabled highDPI on your system"
+				[ "$1" != 'no_hdpi_notification' ] && notify-send "XFWM theme changed to $highDPI_theme" "Changed to the highDPI variant of your chosen theme because you've enabled highDPI on your system"
 				break
 			fi
 		done
 	else
-		# Decrease mouse cursor size if it's greater than or equal to 45
-		if [ "$cursor_size" -ge 45 ]; then
+		# Decrease mouse cursor size if it's equal to 45
+		if [ "$cursor_size" -eq 45 ]; then
 			xfconf-query -c xsettings -p /Gtk/CursorThemeSize -s '25'
 			notify-send 'Mouse cursor size decreased to 25' "Changed to a smaller mouse cursor because you've disabled highDPI on your system"
 		fi
+		# Decrease scaling for QT apps
+		unset logout_required
+		for var in QT_SCALE_FACTOR QT_AUTO_SCREEN_SCALE_FACTOR QT_ENABLE_HIGHDPI_SCALING; do
+			profile_set_variable "$var" 1
+		done
 		for variant in xhdpi hdpi; do
 			# Continue looping if this (highDPI) variant of the theme is not enabled
 			[ "${current_xfwm_theme##*-}" != "$variant" ] && continue
@@ -74,6 +106,10 @@ hdpi_theme_fix() {
 			fi
 		done
 	fi
+	# Show popup menu about logout if it's required
+	[ "$logout_required" = 'true' ] &&
+		yad  --image "dialog-question" --title "Alert" --buttons-layout=center --text-align=center --button=yad-yes:0 --button=yad-no:1 --text 'Logout is required in order to apply the DPI preferences to the QT apps.\nWould you like to logout now?' &&
+		xfce4-session-logout --logout
 }
 
 sync_theme() {
@@ -90,7 +126,7 @@ sync_theme() {
 	xfconf-query -c xfwm4 -p /general/theme -n -t string -s "$current_theme"
 
 	# Change XFWM theme and mouse cursor size according to the user's highDPI setting
-	hdpi_theme_fix
+	hdpi_theme_fix 'no_hdpi_notification'
 
 	# Cleanup flatpak_themes_dir
 	rm -rf "${flatpak_themes_dir:?}"/*