#!/bin/bash

codename=$(cat /etc/os-release | grep UBUNTU_CODENAME | cut -d = -f 2)

if [ "$codename" == "impish" ]
then
source="/usr/share/gnome-shell/theme/Yaru/gnome-shell-theme.gresource"
else
echo "
----------------------------------------
Sorry, Script is only for Ubuntu 21.10
Exiting...
----------------------------------------"
exit 1
fi

pkg=$(dpkg -l | grep libglib2.0-dev >/dev/null && echo "yes" || echo "no")
if [ "$pkg" == "no" ]
then
echo "
-----------------------------------------------------------------------------------------------------
Sorry, the package 'libglib2.0-dev' is not installed. Install the package and then run this Script.
For now, Exiting...
-----------------------------------------------------------------------------------------------------"
exit 1
fi

############################################################################################
case "$1" in ###############################################################################
############################################################################################
--set)
############################################################################################

if [ "$UID" != "0" ]
then
echo "This Script must be run with sudo"
exit 1
fi

echo "
-------------------------------------------------------------------------------------------------------
Please note that after setting login screen background,
>>>>>>>>> Reboot is highly recomonded to see the changes <<<<<<<<<<<<

Do you want to proceed now? [Yes/no] Type n to exit, or press enter to proceed.
-------------------------------------------------------------------------------------------------------"
read answer

if [ "$answer" == "n" ] || [ "$answer" == "N" ]
then
echo "Exiting..."
exit 1
fi

echo "
Please Choose any one number from below.
-------------
1. for Image
2. for Color
-------------"
read a

if [ -z $a ]
then
echo "Option is not selected.
Exiting..."
exit 1
fi

if [ "$a" == "1" ]
then
echo "Enter Image Path for Login Screen
----------------------------------------------------
Example1: /usr/share/backgrounds/2.jpg
Example2: /usr/local/share/backgrounds/spaceship.png
Example3: /home/impish/Downloads/myBG.jpeg
----------------------------------------------------"
read b

elif [ "$a" == "2" ]
then
echo "
Enter Hex Color Code for Login Screen (you may note down colors of your choice from this link https://www.color-hex.com/)
-------------------------------------------------------------------------------------------------------------------------
Example1: #00ff00
Example2: #fca
Example3: #456789
Example4: #123
Example5: #FF00FF
-------------------------------------------------------------------------------------------------------------------------"
read c
fi

if [ -z $b ] && [ -z $c ]
then
echo "Input is not Provided.
Exiting..."
exit 1
fi

if [ -z $c ]
then
color="#042320"
else
color="$c"
fi

if ! [ -z $c ]
then
    	if ! [[ $c =~ ^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$ ]]; then
    	echo "
------------------------------------------------------------------------------------------------------------
    	Sorry it is not a valid Hex color, Please choose the valid HEX color first and then run this script.
------------------------------------------------------------------------------------------------------------"
    	exit 1
    	fi
fi

if ! [ -z $b ]
then
	if ! [ -e $b ]; then
	echo "
---------------------------------------------------------------------------------------------------
Image path you entered does not exist, script defined background color is going to be used for now.
Please notedown the correct file path of the Image and then run this script.
---------------------------------------------------------------------------------------------------"
	fi
fi

prefix="/org/gnome/shell/theme"
dest="/usr/local/share/gnome-shell/theme/impishgdm"

install -D /dev/null $dest/gdm.css
install -D /dev/null $dest/impishgdm.gresource.xml
install -d $dest/icons/scalable/actions

gresource extract $source $prefix/gdm.css > $dest/original.css
gresource extract $source $prefix/checkbox.svg > $dest/checkbox.svg
gresource extract $source $prefix/checkbox-off.svg > $dest/checkbox-off.svg
gresource extract $source $prefix/checkbox-focused.svg > $dest/checkbox-focused.svg
gresource extract $source $prefix/checkbox-off-focused.svg > $dest/checkbox-off-focused.svg
gresource extract $source $prefix/toggle-on.svg > $dest/toggle-on.svg
gresource extract $source $prefix/toggle-off.svg > $dest/toggle-off.svg
gresource extract $source $prefix/icons/scalable/actions/pointer-drag-symbolic.svg > $dest/icons/scalable/actions/pointer-drag-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/keyboard-enter-symbolic.svg > $dest/icons/scalable/actions/keyboard-enter-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/keyboard-hide-symbolic.svg > $dest/icons/scalable/actions/keyboard-hide-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/pointer-secondary-click-symbolic.svg > $dest/icons/scalable/actions/pointer-secondary-click-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/keyboard-shift-filled-symbolic.svg > $dest/icons/scalable/actions/keyboard-shift-filled-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/keyboard-caps-lock-filled-symbolic.svg > $dest/icons/scalable/actions/keyboard-caps-lock-filled-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/pointer-primary-click-symbolic.svg > $dest/icons/scalable/actions/pointer-primary-click-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/keyboard-layout-filled-symbolic.svg > $dest/icons/scalable/actions/keyboard-layout-filled-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/eye-not-looking-symbolic.svg > $dest/icons/scalable/actions/eye-not-looking-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/pointer-double-click-symbolic.svg > $dest/icons/scalable/actions/pointer-double-click-symbolic.svg
gresource extract $source $prefix/icons/scalable/actions/eye-open-negative-filled-symbolic.svg > $dest/icons/scalable/actions/eye-open-negative-filled-symbolic.svg

echo '@import url("resource:///org/gnome/shell/theme/original.css");
  #lockDialogGroup {
  background: '$color' url(file://'$b');
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center; }' > $dest/gdm.css

echo '<?xml version="1.0" encoding="UTF-8"?>
<gresources>
  <gresource prefix="/org/gnome/shell/theme">
    <file>original.css</file>
    <file>gdm.css</file>
    <file>toggle-off.svg</file>
    <file>checkbox-off.svg</file>
    <file>toggle-on.svg</file>
    <file>checkbox-off-focused.svg</file>
    <file>checkbox-focused.svg</file>
    <file>checkbox.svg</file>
    <file>icons/scalable/actions/pointer-drag-symbolic.svg</file>
    <file>icons/scalable/actions/keyboard-enter-symbolic.svg</file>
    <file>icons/scalable/actions/keyboard-hide-symbolic.svg</file>
    <file>icons/scalable/actions/pointer-secondary-click-symbolic.svg</file>
    <file>icons/scalable/actions/keyboard-shift-filled-symbolic.svg</file>
    <file>icons/scalable/actions/keyboard-caps-lock-filled-symbolic.svg</file>
    <file>icons/scalable/actions/pointer-primary-click-symbolic.svg</file>
    <file>icons/scalable/actions/keyboard-layout-filled-symbolic.svg</file>
    <file>icons/scalable/actions/eye-not-looking-symbolic.svg</file>
    <file>icons/scalable/actions/pointer-double-click-symbolic.svg</file>
    <file>icons/scalable/actions/eye-open-negative-filled-symbolic.svg</file>
  </gresource>
</gresources>' > $dest/impishgdm.gresource.xml

cd $dest
glib-compile-resources impishgdm.gresource.xml
mv impishgdm.gresource ..
rm -r $dest
update-alternatives --quiet --install /usr/share/gnome-shell/gdm-theme.gresource gdm-theme.gresource /usr/local/share/gnome-shell/theme/impishgdm.gresource 0
update-alternatives --quiet --set gdm-theme.gresource /usr/local/share/gnome-shell/theme/impishgdm.gresource

check=$(update-alternatives --query gdm-theme.gresource | grep Value | grep /usr/local/share/gnome-shell/theme/impishgdm.gresource >/dev/null && echo "pass" || echo "fail")
if [ "$check" == "pass" ]
then
echo "
				     		---------
						|Success|
						---------"
else
echo Failure
exit 1
fi
;;
############################################################################################
--reset) ###################################################################################
############################################################################################

if [ -e /usr/local/share/gnome-shell/theme/impishgdm.gresource ]
then
rm /usr/local/share/gnome-shell/theme/impishgdm.gresource
update-alternatives --quiet --set gdm-theme.gresource "$source"
cd /usr/local/share
rmdir --ignore-fail-on-non-empty -p gnome-shell/theme
echo "
				     		---------------
						|Reset Success|
						---------------"
else
echo "
-----------------------------------------------------------------------------
No need, Already Reset. (or unlikely background is not set using this Script.)
-----------------------------------------------------------------------------"
exit 1
fi
;;
############################################################################################
*) #########################################################################################
############################################################################################
echo "Use the parameter '--set' or '--reset'; example: './impishgdm --set' or './impishgdm --reset'"
exit 1
esac