#!/bin/sh -e

# NEEDED: lz4 readelf tar cat awk cut sed sh sort

WORKDIR="$(basename "$1")"
if [ -z "$LIBPATH" ]; then
	LIBPATH='/lib'
fi
PRELOAD_SCRIPT='preload'
LIBLIST="$WORKDIR"/liblist
SUMFILE="$WORKDIR"/checksum
tmpfile="$WORKDIR"/tt

die ()
{
	echo "$1"
	exit
}

getlibs ()
{
	tmplist="$WORKDIR"/tmplist

	touch "$LIBLIST"

	# Take the executable and get the first level dependencies
	readelf -d "$1" |
	grep NEEDED |
	awk '{print $5}' |
	sed s/\\[/\ / | sed s/\\]/\ / > "$tmplist"

	# While there are more dependencies
	while [ "$(cat "$tmplist")" ]; do
		# Add them to the master file
		cat "$LIBLIST" "$tmplist" > "$tmpfile"
		mv -f "$tmpfile" "$LIBLIST"

		# Copy them to lib/
		while read -r l; do
			( IFS=:
			for p in $LIBPATH; do
				find -L "$p" -maxdepth 2 -name "$l" -exec cp -n {} "$WORKDIR"/lib/ \;
			done
			)
		done < "$tmplist"

		# Extract their dependencies
		touch "$tmpfile"
		for f in "$WORKDIR"/lib/*; do
			if grep -Fq "$(basename "$f")" "$tmplist"; then
				readelf -d "$f" |
				grep NEEDED |
				awk '{print $5}' |
				sed s/\\[/\ / | sed s/\\]/\ / >> "$tmpfile"
			fi
		done
		sort -u "$tmpfile" > "$tmplist"
	done
	sort -u "$LIBLIST" > "$tmpfile"
	mv -f "$tmpfile" "$LIBLIST"
	rm -f "$tmplist"
}

if ! [ "$WORKDIR" ]; then
	die 'Not enough arguments'
fi

if ! [ -d "$WORKDIR" ]; then
	die 'Argument is not a directory'
fi

if [ -e "$WORKDIR"/bin ]; then 
	if ! [ -d "$WORKDIR"/bin ]; then
		die 'bin/ is not a directory'
	fi
else
	die 'Directory does not contain bin/'
fi

if ! [ -e "$WORKDIR"/id ]; then
	die 'id file not present'
fi

if ls -1 "$WORKDIR"/bin; then
	for f in "$WORKDIR"/bin/*; do
		if ! [ -x "$f" ]; then
			die "$f is not executable"
		fi
	done
else
	die 'bin/ is empty, there has to be at least one executable'
fi

# Create necessary directories and files
mkdir -p "$WORKDIR"/lib
mkdir -p "$WORKDIR"/ext
mkdir -p "$WORKDIR"/man
touch "$WORKDIR"/env

# TODO: add usage and error checking
DIRNAME="$WORKDIR"/"$(head -1 "$WORKDIR"/id | awk '{print $1}')"

echo "Fetching binary dependencies..."
if [ -s "$WORKDIR"/deps ]; then
	while read -r d; do
		( IFS=:
		for p in $PATH; do
			find -L "$p" -maxdepth 2 -name "$d" -exec cp -n {} "$WORKDIR"/bin/ \;
		done
		)
	done < "$tmplist"
fi

echo "Fetching dependencies and stripping binaries..."
# TODO: get al binary dependencies from deps file
# Get all dependencies and strip them
for b in "$WORKDIR"/bin/*; do
	getlibs "$b"
	strip "$b"
done
echo "Stripping libraries..."
for l in "$WORKDIR"/lib/*; do
	strip "$l"
done

echo "Compressing destination directory..."
if [ -d "$DIRNAME" ]; then
	rm -rf "$DIRNAME"
fi
mkdir -p "$DIRNAME"

cp -r "$WORKDIR"/bin "$DIRNAME"/
cp -r "$WORKDIR"/lib "$DIRNAME"/
cp -r "$WORKDIR"/man "$DIRNAME"/
cp -r "$WORKDIR"/ext "$DIRNAME"/
cp "$WORKDIR"/env "$DIRNAME"/
cp "$WORKDIR"/id "$DIRNAME"/

tar -c -f "$DIRNAME".tar -C "$WORKDIR" "$(basename "$DIRNAME")"
md5sum -b "$DIRNAME".tar | cut -d " " -f1 > "$SUMFILE"
lz4 --rm -9 -c "$DIRNAME.tar" > "$DIRNAME".tar.lz4

echo "Injecting payload..."
sed s/SUM/"$(cat "$SUMFILE")"/ "$PRELOAD_SCRIPT" |
sed s/ID/"$(basename "$DIRNAME")"/ |
awk '!/^ *#/ && NF' > tpp

size="$(wc -c tpp | cut -d " " -f1)"
strsize="$(echo "BYTES" | wc -c)"
numsize="$(echo "$size" | wc -c)"
normsize="$((size - (strsize - numsize) + 1))"

sed s/BYTES/"$normsize"/ tpp > tpr
cat tpr "$DIRNAME".tar.lz4 > "$DIRNAME".ti

echo "Cleaning up..."
rm -f tpr tpp
chmod +x "$DIRNAME".ti

rm -rf "$DIRNAME" "$DIRNAME".tar*