#!/bin/zsh -f

# Copyright 2010 - 2011 by Christian J. Robinson <heptite@gmail.com>
# Distributable under the terms of the GNU GPL, version 3 or later.
#
# TODO:
#  - Make the script more generic to convert from and to arbitrary
#    compression formats
#  - Check for decompression and recompression errors
#
# $Id: rar2zip,v 1.2 2011/02/14 02:20:25 infynity Exp $

if [[ $# -le 0 ]]
then
	echo "Usage: ${0##*/} file1.rar [file2.rar ... fileN.rar]" >&2
	exit 1
fi

whence unrar > /dev/null 2>&1 && rarcmd=unrar
whence rar > /dev/null 2>&1 && rarcmd=rar

if [[ -z "$rarcmd" ]]
then
	echo "No rar/unrar command found, bye." >&2
	exit 1
fi

: ${TMPDIR:=/usr/tmp/$LOGNAME}

if [[ ! -e $TMPDIR ]]
then
	mkdir $TMPDIR || exit 1
fi

temp=$(mktemp -d $TMPDIR/rar2zip$$-XXXXXX) || exit 1

cur=$(pwd) || exit 1

cd $temp || exit 1

if [[ ! -z "$(echo *)" ]] 2>/dev/null
then
	echo "Somehow temporary directory \"$temp\" is not empty! Aborting." >&2
	exit 1
fi

for i in $*
do
	if [[ ! -r "$cur/$i" ]]
	then
		echo "File not found or not readable: $i" >&2
		continue
	fi
	if [[ "$i" != *.rar && "$i" != *.RAR ]]
	then
		echo "Not a rar file: $i" >&2
		continue
	fi
	newfile=${i%.rar}.zip
	if [[ -e "$cur/$newfile" ]]
	then
		echo "Skipping: $i  ($newfile already exists)" >&2
		continue
	fi
	cp $cur/$i $temp/
	# $temp is not provided in this command-line due to oddities with Cygwin +
	# "native" Windows applications and path delimiters:
	$rarcmd x $i
	rm -f $temp/$i
	zip -r $temp/$newfile *
	mv $temp/$newfile $cur/
	# This is done because this directory is reused for multiple args:
	rm -rf $temp/*
done

cd $cur || exit 1

rmdir $temp