#!/bin/bash
#
# This script is licensed under the BSD-2-Clause license:
#
# -----//-----
#
# Copyright (c) 2012, Martin Erik Werner <martinerikwerner@gmail.com>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# -----//-----
#
# This script extracts individual sound files from the LIERO.SND binary blob
# and dumps them as wav files, use the 'packsounds' script to pack them back
# up again.
#
# Credit goes to Tim Verweij for information regarding the SND file format:
# http://lierohell.free.fr/lierohack/docformats/liero-snd.html

usage="Usage: $0 <inputfile.SND> <outputdir>"

if [ $# != 2 ]; then
	echo >&2 $usage
	exit 1
fi

if [ ! -r "$1" ]; then
	echo >&2 "Unable to read file '"$1"', aborting"
	exit 1
fi

if [ ! -d "$2" ]; then
	echo >&2 "'"$2"' is not a directory, aborting"
	exit 1
fi

if [ ! -w "$2" ]; then
	echo >&2 "'"$2"' is not writable, aborting"
	exit 1
fi

hash sox 2>&- || { echo >&2 "This script requires the "'"SoX"'" audio manipulator, aborting"; exit 1; }

sndfile="$1"
outputdir="$2"
sounds=30
headersize=2
entrysize=16
nameoffset=0
namesize=8
offsetoffset=8
offsetsize=4
sizeoffset=12
sizesize=4

# Input file:
# header
# NAME|offset|size
# NAME|offset|size
# NAME|offset|size
# Raw PCM sound data (signed 8bit, 22050 Hz, mono)...

# For more info, look at
# echo "$(dd if=$sndfile ibs=1 skip=2 | xxd -g 4 | head -30)"

# For each entry
for i in $(seq 0 $(($sounds - 1))); do
	name="$(dd if=$sndfile ibs=1 \
		skip=$(($i * $entrysize + $(($headersize + $nameoffset)))) \
		count=$namesize 2>/dev/null | tr -d ' ')"

	offset="$((0x$(dd if=$sndfile ibs=1 \
		skip=$(($i * $entrysize + $(($headersize + $offsetoffset)))) \
		count=$offsetsize 2>/dev/null | od -A n -t x4 | tr -d ' ')))"

	size="$((0x$(dd if=$sndfile ibs=1 \
		skip=$(($i * $entrysize + $(($headersize + $sizeoffset)))) \
		count=$sizesize 2>/dev/null | od -A n -t x4 | tr -d ' ')))"

	dd if=$sndfile ibs=1 skip=$offset count=$size 2>/dev/null | \
		sox -t raw -b 8 -e signed-integer -r 22050 -B -c 1 - -t wav "$outputdir"/"$name".wav
done
