#!/bin/bash

set -e

if [ $# -lt 2 ]; then
    echo "$0 [-y|a] root initcounter"
    exit
fi

move=no
append=no
keep=no
author=no

if [ "$1" = "-a" ]; then
    shift
    append=yes
fi

if [ "$1" = "-k" ]; then
    shift
    keep=yes
fi

if [ "$1" = "-e" ]; then
    shift
    author=yes
fi

if [ "$1" = "-y" ]; then
    shift
    move=yes
fi

if [ $keep != yes ]; then
    root=$1
    shift
fi
j=$1

shift 

> /tmp/reverserename
for i in "$@"
do
    test -f "$i" || continue
    ext=${i##*.}

    if [ $keep = yes ]; then
	new=0${j}_${i/#[0-9]*_/}
    elif [ $append = yes ]; then
	new="${root}_${j}.$ext" 
    elif [ $author = yes ]; then
	au=${i##*-}
	[ ! -z $au ] && au="-$au"
	new="${j}_${root}${au}" 
    else
	new="${j}_${root}.$ext" 
    fi
    echo "$i -> $new"
    echo "mv $new $i" >> /tmp/reverserename
    if [ $move = yes ]; then
	mv "$i" "$new"
    fi
    j=`expr $j + 1`
done