#!/usr/local/bin/perl

use strict;

my $DEBUG=0;					#set to 2 to actually see hash tables
my $filenameprefix="";
my $filename="";
my $info="";
my $tmpdateinfo="";
my $filenameprefix="";
my $SKIP="";
my $original_filename="";

use Image::ExifTool 'ImageInfo';

while ($filename=<>) {
    chomp $filename;
	$SKIP=1;
        if ($filename =~ /\.jpg$/i)  { $SKIP=0; }
        if ($filename =~ /\.raw$/i)  { $SKIP=0; }		#no clue if RAW files have EXIF or not
        if ($filename =~ /\.wav$/i)  { $SKIP=0; }		#wikipedia says WAV  can have exif
        if ($filename =~ /\.tiff$/i) { $SKIP=0; }		#wikipedia says TIFF can have exif
	if ($SKIP) { next; }
	$original_filename=$filename;

	if ($DEBUG) { print "filename is $filename\n"; }

	$info = &ImageInfo($filename);											
	if ($DEBUG>1) { foreach my $key (sort keys %$info) { print "key=$key, data=$info->$key\n"; } }

	$tmpdateinfo = $info->{DateTimeOriginal};								
	if ($DEBUG>0) { print "tmpdateinfo for $filename is \"$tmpdateinfo\"\n"; }

	$tmpdateinfo =~ /^([0-9]{4}):([01][0-9]):([0-3][0-9])/;					
	if ($DEBUG>0) { print "for $filename, \$1=$1,\$2=$2,\$3=$3\n"; }

	$filenameprefix  = $1 . $2 . $3;
	if ($filenameprefix ne "") { $filenameprefix .= " - "; }				
	if ($DEBUG>0) { print "fileprefix for $filename is $filenameprefix\n"; }

	##### BONUS FUNCTIONALITY; CLEAN UP THE NAME A BIT:
	$filename =~ s/_IMG.JPG/.jpg/i;									

	print qq[mv "$original_filename" "$filenameprefix$filename"\n];
}