From 11679528b3fadb918337cc7ae75065be0da416ea Mon Sep 17 00:00:00 2001
From: Maxim Likhachev <envrm@yandex.ru>
Date: Fri, 31 Jul 2020 23:53:43 +0300
Subject: [PATCH] ++xsmartlight

---
 README.md   |  1 +
 xsmartlight | 85 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+)
 create mode 100755 xsmartlight

diff --git a/README.md b/README.md
index f3176dd..75071c1 100644
--- a/README.md
+++ b/README.md
@@ -74,6 +74,7 @@ will create the symbolic link for each script in the \<path> directory.
 - [defgroups](defgroups) adds a user to default system groups.
 - [passgen](passgen) creates the strong passwords.
 - [sync-date](sync-date) sets system time according to Google.
+- [xsmartlight](xsmartlight) allows to adjust ASUS smartscreen's brightness.
 - [use](use) shows Gentoo USE flag's description.
 
 ## Development tools
diff --git a/xsmartlight b/xsmartlight
new file mode 100755
index 0000000..f1495e9
--- /dev/null
+++ b/xsmartlight
@@ -0,0 +1,85 @@
+#!/bin/bash
+
+# 
+# Сценарий позволяет регулировать яркость экрана ASUS SmartScreen.
+#
+# Идея и подробности:
+# https://github.com/s-light/ASUS-ZenBook-Pro-Duo-UX581GV/issues/1#issuecomment-632839056
+#
+# Для работы требуется модуль ядра acpi_call
+#
+# Использование:
+# 
+#
+
+percentage2hex() {
+	local decimal=$(( $1 * 255 / 100 ))
+
+	printf "%02x" "$decimal"
+}
+
+set_brightness() {
+	echo "\_SB.ATKD.WMNB 0x0 0x53564544 b32000500${1^^}000000" | tee /proc/acpi/call
+}
+
+main_brightness() {
+	xbacklight | cut -d '.' -f 1
+}
+
+current_brightness() {
+	if [ -f "$BRIGHTNESS_LOG" ]; then
+		cat "$BRIGHTNESS_LOG"
+	else
+		echo "$DEFAULT_BRIGHTNESS"
+	fi
+}
+
+adjust_brightness() {
+	if [ "$1" == "inc" ]; then
+		local adjust_to=$2
+	else
+		local adjust_to=-$2
+	fi
+
+	local new_level=$(( "$(current_brightness)" + "$adjust_to" ))
+
+	if [ "$new_level" -le 0 ];then
+		local new_level=0
+	elif [ "$new_level" -gt 100 ]; then
+		local new_level=100
+	fi
+
+	echo "$new_level"
+}
+
+usage() {
+	echo "USAGE: xsmartlight [options]"
+	echo "  Options:"
+	echo "    -set ?percentage?  set the brightness to <percentage>"
+	echo "    -inc ?percentage?  increase the brigthness to <persentage>% (default is 10%)."
+	echo "    -dec ?percentage?  decrease the brigthness to <persentage>% (default is 10%)."
+	echo "    -help              show this help"
+	echo
+	echo "Executing the xsmartlight command without any options"
+	echo "will set the brightness to default value (${DEFAULT_BRIGHTNESS}%)."
+}
+
+INC=10
+
+DEFAULT_BRIGHTNESS=70 # ~B0
+
+BRIGHTNESS_LOG=/tmp/smartscreen_brightness_level
+
+case "$1" in
+	-set) NEW_LEVEL=${2:-$DEFAULT_BRIGHTNESS};;
+	-inc) NEW_LEVEL=$(adjust_brightness inc "${2:-$INC}");;
+	-dec) NEW_LEVEL=$(adjust_brightness dec "${2:-$INC}");;
+	-help) usage; exit;;
+	*) usage; exit;;
+esac
+
+echo -n "$NEW_LEVEL" | tee "$BRIGHTNESS_LOG"
+echo -n " "
+
+set_brightness "$(percentage2hex "$NEW_LEVEL")"
+