--- loncom/xml/lontexconvert.pm	2008/12/04 09:51:14	1.92
+++ loncom/xml/lontexconvert.pm	2011/12/06 16:10:53	1.109
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # TeX Conversion Module
 #
-# $Id: lontexconvert.pm,v 1.92 2008/12/04 09:51:14 hauer Exp $
+# $Id: lontexconvert.pm,v 1.109 2011/12/06 16:10:53 dseaton Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -47,8 +47,8 @@ use Apache::lonlocal;
 use Apache::lonnet;
 use lib '/home/httpd/lib/perl/';
 use LONCAPA;
-use LWP::UserAgent;
- 
+use URI::Escape;
+use IO::Socket::INET;
 
 # ====================================================================== Header
 
@@ -165,13 +165,56 @@ sub clean_out_math_mode {
 
 sub displaystyle {
     my ($texstring)=@_;
-    #has a $$ or \[ or \displaystyle in it, guessinng it's display mode
+    #has a $$ or \[ or \displaystyle or eqnarray in it, guessinng it's display mode
     if ($$texstring=~/[^\\]\$\$/ ||
-	$$texstring=~/\\\[/ ||
-	$$texstring=~/\\displaystyle/) { return 1; }
+        $$texstring=~/\\\[/ ||
+        $$texstring=~/\\displaystyle/ ||
+        $$texstring=~/eqnarray/
+       ) { return 1; }
     return 0;
 }
 
+sub MathJax_converted {
+    my $texstring=shift;
+    my $tag='math/tex;';
+    if (&displaystyle($texstring)) { $tag='math/tex; mode=display'; }
+    &clean_out_math_mode($texstring);
+    return &MathJax_header().
+      '<script type="'.$tag.'">'.$$texstring.'</script>';
+}
+
+{
+    #Relies heavily on the previous jsMath installation
+    my @MathJax_sent_header;
+    sub MathJax_reset {
+        undef(@MathJax_sent_header);
+    }
+    sub MathJax_push {
+        push(@MathJax_sent_header,0);
+    }
+    sub MathJax_header {
+        if (!@MathJax_sent_header) {
+            &Apache::lonnet::logthis("mismatched calls of MathJax_header and MathJax_process");
+            return '';
+        }
+        return '' if $MathJax_sent_header[-1];
+        $MathJax_sent_header[-1]=1;
+        return
+          '<script type="text/javascript" src="/adm/MathJax/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>'."\n";
+    }
+    #sub MathJax_process {
+    #    my $state = pop(@MathJax_sent_header);
+    #    return '' if !$state;
+    #    return "\n".
+    #        '<script type="text/javascript">MathJax.Process()</script>'."\n";
+    #}
+    #sub MathJax_state {
+    #    my ($level) = @_;
+    #    return $MathJax_sent_header[$level];
+    #}
+}
+
+
 sub jsMath_converted {
     my $texstring=shift;
     my $tag='span';
@@ -239,42 +282,60 @@ sub init_math_support {
 	($inherit_jsmath && &jsMath_state(-2))) {
 	return &Apache::lontexconvert::jsMath_header();
     }
+    &Apache::lontexconvert::MathJax_push();
+    if (lc(&tex_engine()) eq 'mathjax') { # ||
+        #($inherit_jsmath && &jsMath_state(-2))) {
+        return &Apache::lontexconvert::MathJax_header();
+    }
     return;
 }
 
 sub mimetex_valign {
-    my ($texstring)=@_;
-    my $ua = LWP::UserAgent->new; #from the perldoc of LWP::UserAgent
-    $ua->timeout(10); 
-    $ua->env_proxy;
-    #header without imagedata saved to response:
-    my $response = $ua->head('http://lcdevhost.localdomain/cgi-bin/mimetex.cgi?'.$texstring);
-    if ($response->is_success) {
-        #get the valign-value:
-        return($response->headers->{'vertical-align'});}
-    else {
-        return(0); #if (error) than continue without valign
+    my ($esc_texstring)=@_;
+    my $valign = 0;
+    my $path = '/cgi-bin/mimetex.cgi?'.$esc_texstring;
+    my $socket;
+    &Apache::lonxml::start_alarm();
+    $socket = IO::Socket::INET->new(PeerAddr => 'localhost',
+                                    PeerPort => 'http(80)',
+                                    Proto    => 'tcp');
+    if ($socket) {
+        my $headreq = "HEAD $path HTTP/1.0\r\n\r\n";
+        print $socket $headreq;
+        while (<$socket>) {
+            if (/Vertical\-Align\:\s*?([\-\d]+)/) {
+                $valign = $1;
+            }
+        }
+        $socket->close();
     }
+    &Apache::lonxml::end_alarm();
+    return $valign;
 }
 
 sub mimetex_converted {
     my $texstring=shift;
+
+# Alt-Argument for screen readers
+    my $alt_string=$$texstring;
+    $alt_string=~s/\"/\'\'/g;
+
+# Is this displaystyle?
+
     my $displaystyle=&displaystyle($texstring);
 
+# Remove math environment delimiters
+
     &clean_out_math_mode($texstring);
 
     if ($displaystyle) {
 	$$texstring='\\displaystyle \\Large '.$$texstring;
     }
-
-# FIXME
-# this is the line that calls the new function mimetex_valign above:
-#   my $result='<img src="/cgi-bin/mimetex.cgi?'.&escape($$texstring).'" style="vertical-align:'.&mimetex_valign($$texstring).'px" alt="$'.$$texstring.'$" />';
-#
-# this line is the old implementation  without valign of the images:
-    my $result='<img src="/cgi-bin/mimetex.cgi?'.&escape($$texstring).'" alt="$'.$$texstring.'$" />';
+    my $esc_texstring = &uri_escape($$texstring);
+    my $valign = &mimetex_valign($esc_texstring);
+    my $result='<img src="/cgi-bin/mimetex.cgi?'.$esc_texstring.'" style="vertical-align:'.$valign.'px" alt="'.$alt_string.'" />';
     if ($displaystyle) {
-	$result='<center>'.$result.'</center>';
+	$result='<div style="text-align:center">'.$result.'</div>';
     }
     return $result;
 }
@@ -286,8 +347,12 @@ sub converted {
 	return &tth_converted($string);
     } elsif ($mode =~ /jsmath/i) {
 	return &jsMath_converted($string);
+    } elsif ($mode =~ /mathjax/i) {
+	return &MathJax_converted($string);
     } elsif ($mode =~ /mimetex/i) {
 	return &mimetex_converted($string);
+    } elsif ($mode =~ /raw/i) {
+        return $$string;
     }
     return &tth_converted($string);
 }
@@ -296,6 +361,7 @@ sub converted {
 
 sub to_convert {
     my ($string) = @_;
+    &init_tth();
     $string=~s/\<br\s*\/?\>/ /gs;
 #    $string=~s/\s/ /gs;
     $string=&HTML::Entities::decode($string);
@@ -304,24 +370,37 @@ sub to_convert {
 
 sub smiley {
     my $expression=shift;
-    if ($env{'browser.imagesuppress'} eq 'on') { return $expression; }
-    my %smileys=('\:\-\)' => 'smiley',
-		 '8\-\)'  => 'coolsmile',
-		 '8\-(I|\|)'   => 'coolindiff',
-		 ':\-(I|\|)'   => 'neutral',
-		 '\:\-(o|O|\(\))' => 'shocked',
-		 ':\-\('  => 'frowny',
-		 '\;\-\)' => 'wink',
-		 '\:\-P'  => 'baeh',
-		 '\:\-(\\\|\\/)' => 'hrrm',
-		 '\:\-D'  => 'bigsmile',
-		 '\:\-C'  => 'angry',
-		 '\:(\'|\`)\-\(' => 'cry',
-		 '\:\-(X|\#)' => 'lipsrsealed',
-		 '\:\-S' => 'huh');
+    my %smileys=(
+    	 '\:\-*\)' => 'face-smile.png',
+		 '8\-\)'  => 'face-cool.png',
+		 '8\-(I|\|)'   => 'face-glasses.png',
+		 '\:\-(I|\|)'   => 'face-plain.png',
+		 '\:\-(o|O|\(\))' => 'face-surprise.png',
+		 ':\-\('  => 'face-sad.png',
+		 '\;\-\)' => 'face-wink.png',
+		 '\:\-(P|p)'  => 'face-raspberry.png',
+		 '\:\-(\\\|\\/)' => 'face-uncertain.png',
+		 '\:\-D'  => 'face-smile-big.png',
+		 '\:\-(C|\@)'  => 'face-angry.png',
+		 '\:(\'|\`)\-*\(' => 'face-crying.png',
+		 '\:\-(X|x|\#)' => 'face-quiet.png',
+		 '\:\-(s|S)' => 'face-uncertain.png',
+		 '\:\-\$' => 'face-embarrassed.png',
+		 '\:\-\*' => 'face-kiss.png',
+		 '\+O\(' => 'face-sick.png',
+		 '(\&lt\;3|\(heart\))' => 'heart.png',
+		 '\(rose\)' => 'rose.png',
+		 '\(pizza\)' => 'food-pizza.png',
+		 '\(cake\)' => 'food-cake.png',
+		 '\(ninja\)' => 'face-ninja.png',
+		 '\(pirate\)' => 'face-pirate.png',
+		 '\((agree|yes)\)' => 'opinion-agree.png',
+		 '\((disagree|nay)\)' => 'opinion-disagree.png',
+		 '(o|O)\-\)' => 'face-angel.png',
+		 );
     my $iconpath=$Apache::lonnet::perlvar{'lonIconsURL'};
     foreach my $smiley (keys(%smileys)) {
-	$expression=~s/$smiley/\<img src="$iconpath\/$smileys{$smiley}.gif" \/\>/gs; 
+	$expression=~s/$smiley/\<img src="$iconpath\/$smileys{$smiley}" \/\>/gs; 
     }
     return $expression;
 }
@@ -329,7 +408,6 @@ sub smiley {
 sub msgtexconverted {
     my ($message,$email) = @_;
     $errorstring='';
-    &init_tth();
     my $outmessage='';
     my $tex=0;
     foreach my $fragment (split(/(?:\&lt\;|\<)\/*m\s*(?:\&gt\;|\>)/i,$message)) {
@@ -350,15 +428,16 @@ sub msgtexconverted {
     foreach my $fragment (split(/(?:\&lt\;|\<)\/*algebra\s*(?:\&gt\;|\>)/i,
 				$message)) {
 	if ($tex) {
+        my $algebra = &algebra($fragment, 'web', undef, undef, undef, undef, 'tth');
 	    if ($email) {
-		$outmessage.='</pre><tt>'.&algebra($fragment,'web').'</tt><pre>';
+		$outmessage.='</pre><tt>'.$algebra.'</tt><pre>';
 		$tex=0;
 	    } else {
-		$outmessage.=&algebra($fragment,'web');
+		$outmessage.=$algebra;
 		$tex=0;
 	    }
 	} else {
-            $outmessage.=$fragment;
+        $outmessage.=$fragment;
 	    $tex=1;
 	}
     }
@@ -371,9 +450,9 @@ sub msgtexconverted {
 
 sub algebra {
     use AlgParser;
-
-    my ($string,$target,$style,$parstack,$safeeval)=@_;
+    my ($string,$target,$style,$parstack,$safeeval,$tth)=@_;
     my $parser = new AlgParserWithImplicitExpand;
+    if ($tth eq 'tth') {&init_tth();}
     $string=&prepare_algebra($string);
     my $ret = $parser->parse($string);
     my $result='['.&mt('Algebra unconverted due to previous errors').']';
@@ -478,12 +557,47 @@ Header
 
 =item jsMath_converted()
 
+=item MathJax_converted()
+	- Mimics the jsMath functionality
 
 =item tex_engine()
 
 
 =item init_math_support()
 
+=item mimetex_valign()
+
+ Makes a HEAD call to /cgi-bin/mimetex.cgi via IO:: to retrieve the 
+ vertical alignment, before the subsequent call to mimetex_converted()
+ which generates the <img> tag and the corresponding image.
+
+ Input: 1.  $esc_texstring (escaped TeX to be rendered by mimetex).
+ Output: 1. $valign - number of pixels: positive or negative integer 
+            which will be included in <img> tag for mimetex image to
+            support vertical alignment of image within a line of text.
+
+ If a server is running SSL, and Apache rewrite rules are in place 
+ to rewrite requests for http to https, modification will most likely 
+ be needed for pass through for HEAD requests for /cgi-bin/mimetex.cgi. 
+
+ Example rewrite rules which rewrite all http traffic to https, 
+ except HEAD requests for /cgi-bin/mimetex.cgi are:
+
+ <IfModule mod_rewrite.c>
+     RewriteEngine On
+     RewriteLogLevel 0
+
+     RewriteCond %{HTTPS} off
+     RewriteCond %{HTTP:Host} (.*)
+     RewriteCond %{REQUEST_METHOD} !HEAD 
+     RewriteRule ^/(.*) https://%1/$1 [R=301,L]
+
+     RewriteCond %{HTTPS} off
+     RewriteCond %{HTTP:Host} (.*)
+     RewriteCond %{REQUEST_METHOD} HEAD
+     RewriteCond %{REQUEST_URI} !^/cgi-bin/mimetex.cgi
+     RewriteRule ^/(.*) https://%1/$1 [R=301,L]
+ </IfModule>
 
 =item mimetex_converted()