path: root/IkiWiki/Plugin/img.pm

#!/usr/bin/perl
# Ikiwiki enhanced image handling plugin
# Christian Mock cm@tahina.priv.at 20061002
package IkiWiki::Plugin::img;

use warnings;
use strict;
use IkiWiki 3.00;

my %imgdefaults;

sub import {
    hook(type => "getsetup", id => "img", call => \&getsetup);
    hook(type => "preprocess", id => "img", call => \&preprocess, scan => 1);
}

sub getsetup () {
    return
        plugin => {
            safe => 1,
            rebuild => undef,
            section => "widget",
        },
}

sub preprocess (@) {
    my ($image) = $_[0] =~ /$config{wiki_file_regexp}/; # untaint
    my %params=@_;

    if (! defined $image) {
        error("bad image filename");
    }

    if (exists $imgdefaults{$params{page}}) {
        foreach my $key (keys %{$imgdefaults{$params{page}}}) {
            if (! exists $params{$key}) {
                $params{$key}=$imgdefaults{$params{page}}->{$key};
            }
        }
    }

    if (! exists $params{size} || ! length $params{size}) {
        $params{size}='full';
    }

    if ($image eq 'defaults') {
        $imgdefaults{$params{page}} = \%params;
        return '';
    }

    add_link($params{page}, $image);
    add_depends($params{page}, $image);

    # optimisation: detect scan mode, and avoid generating the image
    if (! defined wantarray) {
        return;
    }

    my $file = bestlink($params{page}, $image);
    my $srcfile = srcfile($file, 1);
    if (! length $file || ! defined $srcfile) {
        return htmllink($params{page}, $params{destpage}, $image);
    }

    my $dir = $params{page};
    my $base = IkiWiki::basename($file);
    my $issvg = $base=~s/\.svg$/.png/i;
    my $ispdf = $base=~s/\.pdf$/.png/i;
    my $pagenumber = exists($params{pagenumber}) ? int($params{pagenumber}) : 0;
    if ($pagenumber != 0) {
        $base = "p$pagenumber-$base";
    }

    eval q{use Image::Magick};
    error gettext("Image::Magick is not installed") if $@;
    my $im = Image::Magick->new();
    my $imglink;
    my $imgdatalink;
    my $r = $im->Read("$srcfile\[$pagenumber]");
    error sprintf(gettext("failed to read %s: %s"), $file, $r) if $r;

    if (! defined $im->Get("width") || ! defined $im->Get("height")) {
        error sprintf(gettext("failed to get dimensions of %s"), $file);
    }

    my ($dwidth, $dheight);

    if ($params{size} eq 'full') {
        $dwidth = $im->Get("width");
        $dheight = $im->Get("height");
    } else {
        my ($w, $h) = ($params{size} =~ /^(\d*)x(\d*)$/);
        error sprintf(gettext('wrong size format "%s" (should be WxH)'), $params{size})
            unless (defined $w && defined $h &&
                    (length $w || length $h));

        if ($im->Get("width") == 0 || $im->Get("height") == 0) {
            ($dwidth, $dheight)=(0, 0);
        } elsif (! length $w || (length $h && $im->Get("height")*$w > $h * $im->Get("width"))) {
            # using height because only height is given or ...
            # because original image is more portrait than $w/$h
            # ... slimness of $im > $h/w
            # ... $im->Get("height")/$im->Get("width") > $h/$w
            # ... $im->Get("height")*$w > $h * $im->Get("width")

            $dheight=$h;
            $dwidth=$h / $im->Get("height") * $im->Get("width");
        } else { # (! length $h) or $w is what determines the resized size
            $dwidth=$w;
            $dheight=$w / $im->Get("width") * $im->Get("height");
        }
    }

    if ($dwidth < $im->Get("width") || $ispdf) {
        # resize down, or resize to pixels at all

        my $outfile = "$config{destdir}/$dir/$params{size}-$base";
        $imglink = "$dir/$params{size}-$base";

        will_render($params{page}, $imglink);

        if (-e $outfile && (-M $srcfile >= -M $outfile)) {
            $im = Image::Magick->new;
            $r = $im->Read($outfile);
            error sprintf(gettext("failed to read %s: %s"), $outfile, $r) if $r;
        }
        else {
            $r = $im->Resize(geometry => "${dwidth}x${dheight}");
            error sprintf(gettext("failed to resize: %s"), $r) if $r;

            $im->set(($issvg || $ispdf) ? (magick => 'png') : ());
            my @blob = $im->ImageToBlob();
            # don't actually write resized file in preview mode;
            # rely on width and height settings
            if (! $params{preview}) {
                writefile($imglink, $config{destdir}, $blob[0], 1);
            }
            else {
                eval q{use MIME::Base64};
                error($@) if $@;
                $imgdatalink = "data:image/".$im->Get("magick").";base64,".encode_base64($blob[0]);
            }
        }

        # always get the true size of the resized image (it could be
        # that imagemagick did its calculations differently)
        $dwidth  = $im->Get("width");
        $dheight = $im->Get("height");
    } else {
        $imglink = $file;
    }
    
    if (! defined($dwidth) || ! defined($dheight)) {
        error sprintf(gettext("failed to determine size of image %s"), $file)
    }

    my ($fileurl, $imgurl);
    my $urltobase = $params{preview} ? undef : $params{destpage};
    $fileurl=urlto($file, $urltobase);
    $imgurl=$imgdatalink ? $imgdatalink : urlto($imglink, $urltobase);

    if (! exists $params{class}) {
        $params{class}="img";
    }

    my $attrs='';
    foreach my $attr (qw{alt title class id hspace vspace}) {
        if (exists $params{$attr}) {
            $attrs.=" $attr=\"$params{$attr}\"";
        }
    }
    
    my $imgtag='<img src="'.$imgurl.
        '" width="'.$dwidth.
        '" height="'.$dheight.'"'.
        $attrs.
        (exists $params{align} && ! exists $params{caption} ? ' align="'.$params{align}.'"' : '').
        ' />';

    my $link;
    if (! defined $params{link}) {
        $link=$fileurl;
    }
    elsif ($params{link} =~ /^\w+:\/\//) {
        $link=$params{link};
    }

    if (defined $link) {
        $imgtag='<a href="'.$link.'">'.$imgtag.'</a>';
    }
    else {
        my $b = bestlink($params{page}, $params{link});
    
        if (length $b) {
            add_depends($params{page}, $b, deptype("presence"));
            $imgtag=htmllink($params{page}, $params{destpage},
                $params{link}, linktext => $imgtag,
                noimageinline => 1,
            );
        }
    }

    if (exists $params{caption}) {
        return '<table class="img'.
            (exists $params{align} ? " align-$params{align}" : "").
            '">'.
            '<caption>'.$params{caption}.'</caption>'.
            '<tr><td>'.$imgtag.'</td></tr>'.
            '</table>';
    }
    else {
        return $imgtag;
    }
}

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