use strict;
use warnings;

use Imager;

processPics("./images");

sub processPics {
    my $dir = shift;
    my $newDat = '';

    # build list of jpg files to process
    opendir my $dh, $dir or die "Could not open '$dir' for reading '$!'\n";
    my @pics = grep(/\.jpg$/, readdir $dh);
    closedir $dh;

    # check for subdirs and make if missing
    mkdir "${dir}/medium"  unless (-d "${dir}/medium");
    mkdir "${dir}/thumbs"  unless (-d "${dir}/thumbs");
    mkdir "${dir}/upright" unless (-d "${dir}/upright");

    # process image dir
    for my $p (@pics) {
        my $img = Imager->new(file=>"${dir}/${p}", type=>'jpeg')
            or die Imager->errstr();

        my $med   = $img->copy();
        my $thumb = $img->copy();
        my $rot90;

        # sets width to 750px, write out image
        $med = $img->scale(xpixels=>750);
        $med->write(file=>"${dir}/medium/${p}") or die $med->errstr;

        # sets the height to 150px, write out image
        $thumb = $img->scale(ypixels=>150);
        $thumb->write(file=>"${dir}/thumbs/${p}") or die $thumb->errstr;

        # rotate image, write out image
        $rot90 = $img->rotate(degrees=>-90);
        $rot90->write(file=>"${dir}/upright/${p}") or die $rot90->errstr;

        # append filename without the extension
        $newDat .= (split(/\./, $p))[0] . '|';
    }

    # display $newDat after removing trailing |
    chop $newDat if $newDat;
    print "completed: ${newDat}\n";
}