#!/bin/bash

#Author: Era Scarecrow <rtcvb32@yahoo.com>
#License: GPL 2
#Date: 22 Sep 2021
#Description: Convert Slax bundles to LZO
#
#By default the savechanges and dir2sb files use xz compression, while good for size is terrible for older computers laptops, chromebooks, VM's and the like
#LZO will make it nearly lightning fast. Just specify the mounted directory, which may be /media/sda1 or another folder

if [ ! -e "$1" ]; then
	echo "Add directory of package bundles to be recompressed: ex /media/sda1"
	exit
fi

if [ ! "`whoami`" = 'root' ]; then
	echo "Requires root..."
	su
	if [ ! "`whoami`" = 'root' ]; then
		echo "Not root, probably wouldn't work"
		exit 1
	fi
fi

if [ ! \( -f /usr/bin/sb2dir -a -f /usr/bin/dir2sb -a -f /usr/bin/savechanges -a -d /run/initramfs/memory/bundles \) ]; then
	echo "Error: Utilities sb2dir, dir2sb, savechanges; Are missing, probably not Slax Distro."
	echo "\tuse sb2lzo instead"
	exit 1
fi

#remove trailing slash if there.
DIR=`echo "$1" | sed -E -e 's:/$::'`

if [ ! -f "$DIR/01-lzo.sb" ]; then
	echo "Creating lzo versions & tap-to-touch bundle"

	#make dirs used or not and populate
	mkdir -p /tmp/sb/usr/bin
	mkdir -p /tmp/sb/etc/X11/xorg.conf.d

	#make lzo versions, just replace xz with lzo in scripts
	for X in dir2sb savechanges;
	do
		sed -E -e 's/\bxz\b/lzo/g' "/usr/bin/${X}" > "/tmp/sb/usr/bin/${X}_lzo"
		chmod 755 /tmp/sb/usr/bin/*
	done

	#makes tap-to-touch which is missing in slax.
	#If you don't like it you can always delete it later.
	echo 'Section "InputClass"
        Identifier "libinput touchpad catchall"
        MatchIsTouchpad "on"
        MatchDevicePath "/dev/input/event*"
        Driver "libinput"
        Option "Tapping" "on"
EndSection' > /tmp/sb/etc/X11/xorg.conf.d/40-libinput.conf

	mksquashfs /tmp/sb "$DIR/01-lzo.sb" -comp lzo -b 1024K -always-use-fragments >/dev/null

	#cleanup
	rm -fr /tmp/sb
fi

#runtime bundles location, all mounted readonly directories
cd /run/initramfs/memory/bundles

#cycle through directories of mounted bundles
for X in *;
do
	#if file is present, we don't bother to repack it
	if [ -f "$DIR/$X" ]; then
		continue;
	fi
	
	printf "Repacking: %s" "$X"
	
	#Skips firmware, as you won't need it to be smaller
	echo "$X" | grep "firmware" > /dev/null && echo "	Skipped" && continue;
	
	mksquashfs "$X" "$DIR/$X" -comp lzo -b 1024K -always-use-fragments >/dev/null

	printf "\t%s  ->  %s\n"  `du -h "$DIR/slax/$X" | sed -E -e 's/[^a-zA-Z0-9].*//'`  `du -h "$DIR/$X" | sed -E -e 's/[^a-zA-Z0-9].*//'`
done

echo
sync

echo "Moving and rebooting"
for X in ... .. .;
do
	echo "$X"
	sleep 1
done

cd "$DIR"
mv *.sb slax
sync

#reboot, if done right the live files are LZO now
shutdown -r now