#!/usr/bin/perl -w

#

# set date from exif info

# $Id: exif_rename.pl 208 2003-09-15 12:24:09Z grin $

#

# (c)2003, Peter Gervai

#

use POSIX qw( strftime );

my $exifprog="exiftags";

my $filepattern = qr/^(.+)\.jpg/i;

my $FNAME = "pic";

my $FEXTENSION = "jpg";

my $into_current_dir = 1;

my $DEBUG=0;

my $dir = $ARGV[0];

if( !defined($dir) || !-d $dir ) {

    print "hasznalat: $0 <start directory>\n\n";

    exit;

}

my %files;

&walk_files( $dir, '', \%files );

for my $key (sort keys %files) {

    print "($key) ", $files{$key}[0], '->', $files{$key}[1], "<<\n" if $DEBUG;

    print "mv \"$files{$key}[0]\" \"$files{$key}[1]\"\n";

}

sub walk_files {

    my ($base, $sdir, $rfiles) = @_;

    print "Walking dir $base; $sdir...\n";

    if( !-r "$base/$sdir" ) {

        print "Nem olvashato $base/$sdir!\n";

        return undef;

    }

    opendir( D, "$base/$sdir" );

    my @entries = grep { !/^\.\.?$/ } readdir( D );

    closedir( D );

    foreach my $entry (@entries) {

        if( -f "$base/$sdir/$entry" && $entry =~ /$filepattern/ ) {

            # process file

            my $newname = &get_newname( "$base/$sdir", $entry, $1 );

            my $cnt = 1;

            my $oname = $newname;

            $newname .= ".$FEXTENSION";

            while( defined( $rfiles->{$newname} ) ) {

                print "CLASH $cnt\n" if $DEBUG;

                $newname = "$oname-$cnt.$FEXTENSION";

                $cnt++;

            }

            $rfiles->{$newname} = ["$base/$sdir/$entry", $newname];

            print "Got file $base; $sdir; $entry.\n" if $DEBUG;

        } elsif( -d "$base/$sdir/$entry" ) {

            # walk subdir

            &walk_files( $base, "$sdir/$entry", $rfiles );

        }

    }

}

sub get_newname {

    my ($base, $entry, $basename) = @_;

    my $time = &get_exif_time( "$base/$entry" );

    my $newname;

    if( $into_current_dir ) {

        $newname = "./$FNAME-$time";

    } else {

        $newname = "$base/$FNAME-$time";

    }

    return $newname;

}

sub get_exif_time {

    my $file = shift;

    if( -f $file ) {

        my $res = qx( $exifprog "$file" 2> /dev/null );

        if( $res =~ m/Image Created: (\S+ \S+)/ ) {

            #print "res=$_>>$1<<\n";

            # s m h md m y

            my @d = split /[: ]/, $1;

            #print "mon:", join(",", @d) , "<<\n";

            $d[1] -= 1;

            $d[0] -= 1900;

            return strftime("%Y.%m.%d-%H.%M.%S",  @d[5,4,3,2,1,0] );

        }

    }

    return "none";

}