#!/usr/bin/perl
# The LearningOnline Network with CAPA
# randomlabel.png: composite together text and images into 1 image
#
# $Id: randomlylabel.pm,v 1.16 2004/02/23 22:52:30 albertel Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
###

package Apache::randomlylabel;

use strict;
use Image::Magick;
use Apache::Constants qw(:common);
use Apache::loncommon();
use GD();
use GD::Polyline();
use LWP::UserAgent();

sub get_image {
    my ($imgsrc,$set_trans)=@_;
    my $image;
    &Apache::lonnet::logthis("imagesrc1 is $imgsrc");
    if ($imgsrc !~ m|^(/home/)|) {
	&Apache::lonnet::logthis("imagesrc2 is $imgsrc");
	if ($imgsrc !~ /^http:/) {
	    $imgsrc="http://".$ENV{'HTTP_HOST'}.$imgsrc;
	}
	&Apache::lonnet::logthis("imagesrc3 is $imgsrc");
	&Apache::lonnet::logthis("LWP fetching image $imgsrc");
	my $ua=new LWP::UserAgent;
	my $request=new HTTP::Request('GET',"$imgsrc");
	$request->header(Cookie => $ENV{'HTTP_COOKIE'});
	my $file="/tmp/imagetmp".$$;
	my $response=$ua->request($request,$file);
	&Apache::lonnet::logthis("contetn is ".$response->content_type);
	&Apache::lonnet::logthis($response->is_success);
	&Apache::lonnet::logthis($response->status_line);
	if ($response->is_success) {
	    if ($response->content_type !~ m-/(png|jpg|jpeg)$-i) {
		my $conv_image = Image::Magick->new;
		my $current_figure = $conv_image->Read('filename'=>$file);
		$conv_image->Set('magick'=>'png');
		my @blobs=$conv_image->ImageToBlob();
		undef $conv_image;
		$image = GD::Image->new($blobs[0]);
	    } else {
		GD::Image->trueColor(1);
		$image = GD::Image->new($file);
	    }
	}
    } elsif ($imgsrc !~ /\.(png|jpg|jpeg)$/i) {
	my $conv_image = Image::Magick->new;
	my $current_figure = $conv_image->Read('filename'=>$imgsrc);
	$conv_image->Set('magick'=>'png');
	my @blobs=$conv_image->ImageToBlob();
	undef $conv_image;
	$image = GD::Image->new($blobs[0]);
    } else {
	GD::Image->trueColor(1);
	$image = GD::Image->new($imgsrc);
    }
    if ($set_trans && defined($image)) {
	my $white=$image->colorExact(255,255,255);
	if ($white != -1) { $image->transparent($white); }
    }
    return $image;
}

sub get_color_from_hexstring {
    my ($image,$color)=@_;
    if (!$color) { $color='000000'; }
    my (undef,$red,undef,$green,undef,$blue)=split(/(..)/,$color);
    $red=hex($red);$green=hex($green);$blue=hex($blue);
    my $imcolor;
    if (!($imcolor = $image->colorResolve($red,$green,$blue))) {
	$imcolor = $image->colorClosestHWB($red,$green,$blue);
    }
    return $imcolor;
}

sub handler {
    my $r = shift;
    $r->content_type('image/png');
    $r->send_http_header;
    my (undef,$id) = split(/=/,$ENV{'QUERY_STRING'});
    &Apache::lonnet::logthis("BGIMG is ".$ENV{"cgi.$id.BGIMG"});
    my $image=&get_image(&Apache::lonnet::unescape($ENV{"cgi.$id.BGIMG"}),0);
    if (! defined($image)) {
        &Apache::lonnet::logthis('Unable to create image object for -'.$id.'-'.
				 $ENV{"cgi.$id.BGIMG"});
        return OK;
    } elsif (defined($ENV{"cgi.$id.SIZE"})) {
	my ($width,$height)=split(':',$ENV{"cgi.$id.SIZE"});
	$image = new GD::Image($width,$height,1);
	my ($bgcolor)=split(':',$ENV{"cgi.$id.BGCOLOR"});
	if ($bgcolor ne 'transparent') {
	    $bgcolor=&get_color_from_hexstring($image,$bgcolor);
#	$image->rectangle(0,0,$width,$height,$bgcolor);
	    $image->fill(0,0,$bgcolor);
	} else {
	    $bgcolor=&get_color_from_hexstring($image,'FFFFFF');
	    $image->fill(0,0,$bgcolor);
	    $image->transparent($bgcolor);
	}
    } else {
	&Apache::lonnet::logthis('Unable to create image object, no info');
	return OK;
    }
    #binmode(STDOUT);
    my @objtypes=split(':',$ENV{"cgi.$id.OBJTYPE"});
    foreach(my $i=0;$i<$ENV{"cgi.$id.OBJCOUNT"};$i++) {
	my $type=shift(@objtypes);
	&Apache::lonnet::logthis("type is $type");
	if ($type eq 'LINE') {
	    my ($x1,$y1,$x2,$y2,$color,$thickness)=
		split(':',$ENV{"cgi.$id.OBJ$i"});
	    my $imcolor=&get_color_from_hexstring($image,$color);
	    if (!defined($thickness)) { $thickness=1; }
	    $image->setThickness($thickness);
	    $image->setAntiAliased($imcolor);
	    $image->line($x1,$y1,$x2,$y2,gdAntiAliased);
	} elsif ($type eq 'RECTANGLE') {
	    my ($x1,$y1,$x2,$y2,$color,$thickness,$filled)=
		split(':',$ENV{"cgi.$id.OBJ$i"});
	    if ($x1 > $x2) { my $temp=$x1;$x1=$x2;$x2=$temp; }
	    if ($y1 > $y2) { my $temp=$y1;$y1=$y2;$y2=$temp; }
	    my $imcolor=&get_color_from_hexstring($image,$color);
	    if (!defined($thickness)) { $thickness=1; }
	    $image->setThickness($thickness);
#	    $image->setAntiAliased($imcolor);
	    if ($filled) {
		$image->filledRectangle($x1,$y1,$x2,$y2,$imcolor);
	    } else {
		$image->rectangle($x1,$y1,$x2,$y2,$imcolor);
	    }
	} elsif ($type eq 'POLYGON') {
	    my ($color,$width,$open)=split(':',$ENV{"cgi.$id.OBJ$i"});
	    my $imcolor=&get_color_from_hexstring($image,$color);
	    my $polygon = (($open) ? (new GD::Polyline) : (new GD::Polygon));
	    foreach my $coord (split('-',$ENV{"cgi.$id.OBJEXTRA$i"})) {
		my ($x,$y)=($coord=~m/\(([0-9]+),([0-9]+)\)/);
		$polygon->addPt($x,$y);
	    }
	    $image->setThickness($width);
	    if ($open) {
		$image->polydraw($polygon,$imcolor);
	    } else {
		$image->polygon($polygon,$imcolor);
	    }
	} elsif ($type eq 'ARC') {
	    my ($x,$y,$width,$height,$start,$end,$color,$thickness,$filled)=
		split(':',$ENV{"cgi.$id.OBJ$i"});
	    if (!$color) { $color='000000'; }
	    my $imcolor=&get_color_from_hexstring($image,$color);
	    if (!defined($thickness)) { $thickness=1; }
	    $image->setThickness($thickness);
#	    $image->setAntiAliased($imcolor);
	    if ($filled) {
		$image->filledArc($x,$y,$width,$height,$start,$end,
				  $imcolor);
	    } else {
		$image->arc($x,$y,$width,$height,$start,$end,$imcolor);
	    }
	} elsif ($type eq 'FILL') {
	    my ($x,$y,$color)=split(':',$ENV{"cgi.$id.OBJ$i"});
	    if (!$color) { $color='000000'; }
	    my $imcolor=&get_color_from_hexstring($image,$color);
	    $image->fill($x,$y,$imcolor);
	} elsif ($type eq 'IMAGE') {
	    my ($x,$y,$file,$transparent)=split(':',$ENV{"cgi.$id.OBJ$i"});
	    $file=&Apache::lonnet::unescape($file);
	    if (!defined($transparent)) { $transparent=1; }
	    my $subimage=&get_image($file,$transparent);
	    if (!defined($subimage)) {
		&Apache::lonnet::logthis('Unable to create image object for '.
					 $file);
		next;
	    }
	    $image->copy($subimage,$x,$y,0,0,$subimage->getBounds());
	} elsif ($type eq 'LABEL') {
	    my ($x,$y,$text,$font,$color)=split(':',$ENV{"cgi.$id.OBJ$i"});
	    $text=&Apache::lonnet::unescape($text);
	    my $imcolor=&get_color_from_hexstring($image,$color);
	    my $height=GD::Font->Giant->height;
	    for(my $i=0;$i<$ENV{"cgi.$id.COUNT"};$i++) {
		$image->string(GD::gdGiantFont,$x,$y-$height,$text,$black);
	    }
	}
    }
    $image->setThickness(1);
    $r->print($image->png);
    return OK;
}

1;