#!/bin/sh

ERR () {
	printf '[ERROR] %s' "$1"
	test -n "$2" && exit "$2"
}

file_path="$1"
test -n "$file_path" || { echo 'No file given'; exit 1; }
file="$(basename "$file_path")"
name="$(echo "$file" | cut -d. -f1)"
_name="__${name}__"
ext="$(echo "$file" | cut -d. -f2)"
block_dev="/dev/mapper/${_name}"
cur_uid="$(id -u)"
cur_gid="$(id -g)"

sudo_prog='sudo --prompt=Sudo_Password:'

test "$ext" = 'luks' || ERR "File $file_path does not have extencion .luks." 1

if test -e "$file_path"
then
	test -f "$file_path" || ERR "${file_path} Is not a regular file" 1
else
	echo -n "File ${file_path} does not exist. Want to create? (Y/n) "
	read choose
	case "$choose" in
		N|n) exit 1 ;;
	esac

	echo -n "What size? (10G) "
	read _size
	if test "$choose" = ''
	then
		_size='10G'
	fi
	truncate --size="$_size" "$file_path" || ERR "Failed to allocate file: ${file_path}" 1

	cryptsetup luksFormat -c aes-xts-plain64 -s 512 -y "$file_path" || ERR "Failed to format file: ${file_path}" 1

	echo "Successifuly create encrypted file: ${file_path}"
fi

if test -e ./"$name"
then
	test -d "./${name}" || ERR "File ${name} already exist in current directory. And is not a directory." 1

	if test -b "$block_dev"
	then
		echo -n "File ${file_path} Already open. Want to close? (Y/n) "
		read choose
		case "$choose" in
			N|n) exit 0 ;;
		esac
		echo "Unmounting ./${name}"
		$sudo_prog umount ./"$name" || ERR "Failed to unmount ./${name}." 1

		echo "Closing luks block dev ${block_dev}"
		$sudo_prog cryptsetup close "$block_dev" || ERR "Failed to close luks file: ${file_path}." 1

		echo "Succesfully Closed ${file_path}."

		echo -n "Delete directory ./${name}? (Y/n) "
		read choose
		case "$choose" in
			N|n) exit 0 ;;
		esac

		rmdir ./$name || ERR "Failed to remove directory: ./${name}" 1
		exit 0
	fi

else
	mkdir ./"$name"
fi

echo "Opening luks file: ${file_path} as ${_name}."
$sudo_prog cryptsetup luksOpen "$file_path" "$_name" || ERR "Failed to open luks file: ${file_path}." 1

echo "Mounting ${block_dev} into ./${name}"
$sudo_prog mount "$block_dev" ./"$name" || ERR "Failed to mound ${block_dev} on ./${name}." 1

dir_perm="$(stat -c '%u:%g' "$file_path")"
cur_perm="${cur_uid}:${cur_gid}"
if ! test "$dir_perm" = "$cur_perm"
then
	(
		echo -n "Directory ./${name} not owned by current user. Want to change direcory owner? (Y/n) "
		read choose
		case "$choose" in
			N|n) exit 0 ;;
		esac
		echo "Changing ownership of ./${name} from ${dir_perm} to ${cur_perm}."
		$sudo_prog chown "$cur_perm" ./"$name" || ERR "Failed to change permission of directory ./${name} from ${dir_perm} to ${cur_perm}." 1
	) || exit 1
fi

echo "Opened ${file_path} on ./${name}"

exit 0