File Coverage

blib/lib/IIIF/Request.pm

Criterion	Covered	Total	%
statement	111	111	100.0
branch	77	82	93.9
condition	64	73	87.6
subroutine	11	11	100.0
pod	5	6	83.3
total	268	283	94.7

package IIIF::Request;
use 5.014001;

our $VERSION = "0.07";

use Plack::Util::Accessor qw(region size rotation quality format);
use Carp qw(croak);
use List::Util qw(min);

our $XY  = qr{[0-9]+};               # non-negative integer
our $WH  = qr{[1-9][0-9]*};          # positive integer
our $NUM = qr{[0-9]*(\.[0-9]+)?};    # non-negative
our $REGION   = qr{full|square|($XY,$XY,$WH,$WH)|pct:($NUM,$NUM,$NUM,$NUM)};
our $SIZE     = qr{(\^)?(max|pct:($NUM)|($WH,)|(,$WH)|(!)?($WH,$WH))};
our $ROTATION = qr{([!])?($NUM)};
our $QUALITY  = qr{color|gray|bitonal|default};
our $FORMAT   = qr{[^.]+};

use overload '""' => \&as_string, fallback => 1;

sub new {
    my $class = shift;
    my $path = shift // "";

    my (
        $rotation, $mirror,     $degree,    $quality, $format,
        $region,   $region_pct, $region_px, $size,    $upscale,
        $size_px,  $size_pct,   $ratio
    );

    my @parts = split '/', $path;

    if ( @parts && $parts[0] =~ /^$REGION$/ ) {
        $region = shift @parts;
        if ($1) {
            $region_px = [ split ',', $1 ];
        }
        elsif ($2) {
            $region_pct = [ map { 1 * $_ } split ',', $2 ];
            error("disallowed percentage value")
              if !$region_pct->[2]
              || !$region_pct->[3]
              || grep { $_ > 100 } @$region_pct;
        }
    }

    if ( @parts && $parts[0] =~ /^$SIZE$/ ) {
        $size    = shift @parts;
        $upscale = $1;
        $ratio   = $7;
        $size_px = [ split ',', $5 // $6 // $8 ] if $5 // $6 // $8;

        if ( defined $3 ) {
            $size_pct = 1 * $3;
            if ($upscale) {
                $size = "^pct:$size_pct";
            }
            else {
                error("disallowed percentage value")
                  if $size_pct == 0.0 || $size_pct > 100.0;
                $size = "pct:$size_pct";
            }
        }
    }

    if ( @parts && $parts[0] =~ /^$ROTATION$/ ) {
        shift @parts;
        $mirror = !!$1;

        # normalize to 0...<360 with up to 6 decimal points
        $degree = 1 * sprintf( "%.6f", $2 - int( $2 / 360 ) * 360 );
        $rotation = $mirror ? "!$degree" : "$degree";
    }

    if ( @parts && $parts[0] =~ /^(($QUALITY)([.]($FORMAT))?|[.]($FORMAT))$/ ) {
        $quality = $2;
        $format = $4 // $5;
        shift @parts;
    }

    error( "failed to parse '" . join( '/', '', @parts ) . "'" )
      if @parts;

    bless {
        region => $region // 'full',
        region_pct => $region_pct,
        region_px  => $region_px,
        size       => $size // 'max',
        upscale    => $upscale,
        size_pct   => $size_pct,
        size_px    => $size_px,
        ratio      => $ratio,
        rotation   => $rotation // '0',
        mirror     => $mirror,
        degree     => $degree,
        quality    => $quality // 'default',
        format     => $format
    }, $class;
}

sub error {
    croak "Invalid IIIF Image API Request: $_[0]";
}

sub canonical {
    my ( $self, $width, $height, %max ) = @_;

    # convert region to /full|x,y,w,h/
    my $region = $self->{region};
    if ( $self->{region} eq 'square' ) {
        my $size = min( $width, $height );
        $region = "0,0,$size,$size";
    }
    elsif ( $self->{region_pct} ) {
        my ( $x, $y, $w, $h ) = @{ $self->{region_pct} };
        $x = pct2px( $x, $width );
        $y = pct2px( $y, $height );
        $w = pct2px( $w, $width ) or return;
        $h = pct2px( $h, $height ) or return;
        $region = "$x,$y,$w,$h";
    }
    elsif ( $self->{region_px} ) {    # region outside of image dimensions?
        my ( $x, $y, $w, $h ) = @{ $self->{region_px} };
        return if $x >= $width && $y >= $height;
    }
    $region = 'full' if $region eq "0,0,$width,$height";

    # proceed with region size
    if ( $region ne 'full' ) {
        ( undef, undef, $width, $height ) = split ',', $region;
    }

    if ( $self->{size_pct} ) {        # too small
        return
          if !pct2px( $self->{size_pct}, $width )
          || !pct2px( $self->{size_pct}, $height );
    }

    # convert size to /[^]?(max|w,h)/
    my $size    = $self->{size};
    my $upscale = $self->{upscale};
    my $ratio   = $self->{ratio};
    my $size_px = $self->{size_px};

    my $maxHeight = $max{maxHeight};
    my $maxWidth = $max{maxWidth} || $maxHeight;

    if ( $size eq '^max' && $maxHeight ) {
        $size_px = [ $maxWidth, $maxHeight ];
        $upscale = 1;
        $ratio   = 1;
        $size    = '^!' . join ',', @$size_px;
    }

    if ( $size !~ /\^?max/ ) {
        if ( $self->{size_pct} ) {
            $size = join ',',
              map { pct2px( $self->{size_pct}, $_ ) } ( $width, $height );
            $size = "^$size" if $upscale;
        }
        else {
            my ( $w, $h ) = @$size_px;
            return if !$w && !$h;
            return if !$upscale && ( $h > $height || $w > $width );

            if ( $w && $h ) {
                if ($ratio) {
                    if ( $w / $h > $width / $height ) {
                        $w = pct2px( 100 * $width / $height, $h );
                    }
                    else {
                        $h = pct2px( 100 * $height / $width, $w );
                    }
                }

                $size = "$w,$h";
            }
            elsif ($w) {
                $size = "$w," . pct2px( 100 * $height / $width, $w );
            }
            elsif ($h) {
                $size = pct2px( 100 * $width / $height, $h ) . ",$h";
            }

            $size = "^$size" if $upscale;
        }

        $size = "max" if $size =~ /^\^?$width,$height$/;
    }

    # give up if image too large
    if ($maxHeight) {
        ( $width, $height ) = ( $1, $2 ) if $size =~ /^\^?(\d+),(\d+)$/;
        return if $width > $maxWidth || $height > $maxHeight;
    }

    my $str = join '/', $region, $size, $self->{rotation}, $self->{quality};
    return defined $self->{format} ? "$str.$self->{format}" : $str;
}

sub pct2px {
    my ( $percent, $value ) = @_;
    return int( $percent * $value / 100 + 0.5 );
}

sub is_default {
    my ($self) = @_;

    return $self->as_string =~ qr{^full/max/0/default};
}

sub as_string {
    my ($self) = @_;

    my $str = join '/', map { $self->{$_} } qw(region size rotation quality);
    return defined $self->{format} ? "$str.$self->{format}" : $str;
}

1;
__END__