#!/bin/bash
#SH #!/usr/bin/env bash
#SH This is portable, but has a different set of issues.
#SH An attacker could alter $PATH and place a bash before
#SH the real location. It's unlikely, but some feel better
#SH with the absolute path here. So... okay.
# 
# .spls to .wav+.mp3 batch processing and conversion
# ==================================================
#
# This file can be executed as wrapper for SOMPYLER_DIRECTORY/scripts/sompyle
# that also autodetects and reuses any cache directory for the given spls
# file, so tones for notes that have not been changed or added are not
# re-rendered.
#
# This is only a script for convenience; scripts/sompyle is usable without.
#
# PREREQUISITES:
# --------------
#
# Make sure you have installed following tools:
#
# - GNU find or any other find supporting -samefile operator
# - lame: LAME Encoder
#
#
# INSTALLATION:
# -------------
#
# Symlink this file from a /bin-directory in your $PATH, or copy and adjust
# it according to your needs.
#
#
# USAGE:
# ------
#
# $name_of_link [OPTIONS --] FILE [FILE2 FILE3 ... FILEn]
#
# The OPTIONS are simply passed to the wrapped script. Execute
# scripts/sompyle without parameters to get a list and usage help.
#
# Do not forget the final "--" that means that following parameters are the
# files to process. Files indicated without .spls suffix are regarded as
# having one and they must be contained in $SOMPYLER_DIRECTORY/scores/.
#
# 
# CAUTION:
# --------
#
# This script is not quite portable, yet.

# Replace if you have copied and customized scripts/sompyle-wrapper.sh:
homedir=$(cd "$(dirname $(readlink $0))"/..; pwd)
#SH Why readlink here (doesn't work the same way on BSD)? You want
#SH the parent directory of the script? As you're in bash anyway, you
#SH can: homedir="${PWD%/*}" or even pushd ../ and change the working
#SH directory.

# Use temporary directory as is stored in ${TMPDIR} environment variable
# If not set, assume /tmp.
export tempdir=${TMPDIR:-/tmp}
#SH I'm not sure if it is strictly necessary to quote subshells, but I
#SH feel better with it.

# Supported by shells with array support
declare -a FILES ARGS

for i in "$@"; do
    if [ $i == "--" ]; then
       ARGS_ONLY=0
    elif [ "$ARGS_ONLY" == 1 ] || [[ "$i" == -* ]]; then
       ARGS+=("$i")
       ARGS_ONLY=1
    else
       FILES+=("$i")
    fi
done
#SH Bash has getopts. It also supports the "--" case.
#SH Tutorial here: http://wiki.bash-hackers.org/howto/getopts_tutorial
#SH or man bash /getopts (a bit cryptic, though)

for score in "${FILES[@]}"; do
    if [ "${score}" != "*.spls" ]; then
#SH $score must be "*.spls" to make this false. Is this intended?
#SH Or do you rather mean somthing like [[ "$score" =~ .*\.spls ]],
#SH Which is true for all .spls files?
        score="${homedir}/scores/${score}.spls"
    fi
    out="${tempdir}/$(basename "${score%.spls}").wav"
    tmp="$(find -L ${tempdir} -wholename "${tempdir}/sompyler*/score" -samefile "${score}" 2> /dev/null | head -1)"
    if [ -n "$tmp" ]; then
	# First argument to scripts/sompyle can be a directory instead of a
	# .spls file. This directory is expected to contain a "./score" file
	# or symlink to a real .spls file. So just let us overwrite it:
        score="$(dirname $tmp)"
        echo "Let's reuse cache directory ${score} with 'score' linking to requested file ..."
    fi
    "${homedir}/scripts/sompyle" "${score}" "${out}" "${ARGS[@]}" \
    	&& lame "${out}" && rm "${out}"
done