--- loncom/xml/lontexconvert.pm	2001/05/03 22:54:12	1.2
+++ loncom/xml/lontexconvert.pm	2006/05/17 22:08:08	1.73
@@ -1,86 +1,367 @@
 # The LearningOnline Network with CAPA
 # TeX Conversion Module
 #
-# 05/29/00,05/30,10/11,10/20 Gerd Kortemeyer
-# 05/03/2001 Scott Harrison
+# $Id: lontexconvert.pm,v 1.73 2006/05/17 22:08:08 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/
+#
+# Copyright for TtHfunc and TtMfunc by Ian Hutchinson. 
+# TtHfunc and TtMfunc (the "Code") may be compiled and linked into 
+# binary executable programs or libraries distributed by the 
+# Michigan State University (the "Licensee"), but any binaries so 
+# distributed are hereby licensed only for use in the context
+# of a program or computational system for which the Licensee is the 
+# primary author or distributor, and which performs substantial 
+# additional tasks beyond the translation of (La)TeX into HTML.
+# The C source of the Code may not be distributed by the Licensee
+# to any other parties under any circumstances.
+#
 
 package Apache::lontexconvert;
 
 use strict;
-use tth;
+use tth();
 use vars qw($errorstring);
-use Apache::lonmsg;
+#use Apache::lonxml();
+use Apache::lonlocal;
+use Apache::lonnet;
 
 # ====================================================================== Header
 
-sub header {
-  $errorstring='';
-  my $time=time;
-  my $addhead=<<END;
-<script language="JavaScript">
-    if (window.location.pathname!="/res/adm/pages/menu.html") {
-	menu=window.open("","LONCAPAmenu");
-	menu.currentURL=window.location.pathname;
-    }
-</script>
-END
-  if ($ENV{'browser.mathml'}) {
-      &tth::ttminit();
-      return '<?xml version="1.0"?>'
-            .'<?xml-stylesheet type="text/css" href="/adm/MathML/mathml.css"?>'
-            .'<!DOCTYPE html SYSTEM "/adm/MathML/mathml.dtd" '
-            .'[<!ENTITY mathns "http://www.w3.org/1998/Math/MathML">]>'
-            .'<html xmlns:math="http://www.w3.org/1998/Math/MathML" ' 
-            .'xmlns="http://www.w3.org/TR/REC-html40">'
-	    ."<head>$addhead</head>"
-            ."\n";
-  } else {
-      &tth::tthinit();
-      my $headerstring='<html>';
-      if ($ENV{'browser.os'} eq 'mac') { 
-         $headerstring.="<head>\n"
-             .'<meta Content-Type="text/html; charset=x-mac-roman">'
-	     ."\n$addhead</head>\n";
-      }
-      else {
-	  $headerstring.="<head>$addhead</head>";
-      }
-      return $headerstring."\n";
-  }
+sub init_tth {
+    my $options=$env{'course.'.$env{'request.course.id'}.'.tthoptions'};
+    if ($env{'browser.mathml'}) {
+	&tth::ttminit();
+	if ($env{'browser.unicode'}) {
+	    &tth::ttmoptions('-L -u1 '.$options);
+	} else {
+	    &tth::ttmoptions('-L -u0 '.$options);
+	}
+    } else {
+	&tth::tthinit();
+	if ($env{'browser.unicode'}) {
+	    &tth::tthoptions('-L -u1 '.$options);
+	} else {
+	    &tth::tthoptions('-L -u0 '.$options);
+	}
+    }
 }
 
 # ================================================================== Conversion
 
-sub converted {
+$Apache::lontexconvert::messedup=0;
+
+# we need this routine because &converted can get called from inside
+# of the safespace (through &xmlparse('<m>stuff</m>') which doesn't
+# allow the opcode for alarm, so we need to compile this before we get
+# into the safe space since opcode checks only occur at compile time
+sub convert_real {
+    my ($texstring)=@_;
+    my ($xmlstring,$errorstring);
+    local $SIG{SEGV}=sub { $Apache::lontexconvert::messedup=1; die; };
+    local $SIG{ALRM}=sub { 
+	&Apache::lonnet::logthis("ALRM");
+	$xmlstring='['.&mt("TeX unconverted due to errors").']';
+	$Apache::lontexconvert::messedup=1;
+	die &mt("TeX unconverted due to errors");
+    };
+    &Apache::lonxml::start_alarm();
+    if ($env{'browser.mathml'}) {
+	$xmlstring=&tth::ttm($$texstring);
+	$xmlstring=~s/\<math\>/\<math xmlns=\"\&mathns\;\"\>/g;
+	$xmlstring=~s/\<br\>/\<br\/\>/g;
+	$xmlstring=~s/\<p\>/\<p\>\<\/p\>/g;
+	$errorstring.=&tth::ttmerror();
+    } else {
+	$xmlstring=&tth::tth($$texstring);
+	$errorstring.=&tth::ttherror();
+	$xmlstring=~s-</font(\s*)>-</font>-g;
+    }
+    $xmlstring=~s/^\s*\<br clear\=\"all\"/\<br/s;
+    $xmlstring=~s/^\s*//;
+    $xmlstring=~s/\s*$//;
+    &Apache::lonxml::end_alarm();
+    return ($xmlstring,$errorstring);
+}
+
+sub tth_converted {
+    my $texstring=shift;
+    my $xmlstring='['.&mt('UNDISPLAYABLE').']';
+    if ($Apache::lontexconvert::messedup) {
+	return '['.&mt('TeX unconverted due to previous errors').']';
+    }
+    $$texstring ='\\documentstyle{article}'.$$texstring;
+
+    eval(<<'ENDCONV');
+    ($xmlstring,$errorstring)=&convert_real($texstring)
+ENDCONV
+    if ($@) {
+	$errorstring.=&mt("Evaluation Error: ").$@;
+	$Apache::lontexconvert::messedup=1;
+    }
+    if ($Apache::lontexconvert::messedup || &tth::tthmessedup() || 
+	$errorstring) {
+	&Apache::lonnet::logthis("Trying to kill myself");
+	$Apache::lontexconvert::messedup=1;
+	if (ref($Apache::lonxml::request)) {
+	    $Apache::lonxml::request->child_terminate();
+	} else {
+	    my $request;
+	    eval { $request=Apache->request; };
+	    if (!$request) {
+		eval { $request=Apache2::RequestUtil->request; };
+	    }
+	    if ($request) {
+		$request->child_terminate();
+	    } else {
+		&Apache::lonnet::logthis("Unable to find a request to do child_terminate on");
+	    }
+	}
+    }
+    return $xmlstring;
+}
+
+sub clean_out_math_mode {
+    my ($texstring)=@_;
+    $$texstring=~s/(?!\\)\$//g;
+    $$texstring=~s/\\[\)\(\]\[]//g;
+    $$texstring=~s/\\ensuremath//g;
+    return '';
+}
+
+sub displaystyle {
+    my ($texstring)=@_;
+    #has a $$ or \[ or \displaystyle in it, guessinng it's display mode
+    if ($$texstring=~/[^\\]\$\$/ ||
+	$$texstring=~/\\\[/ ||
+	$$texstring=~/\\displaystyle/) { return 1; }
+    return 0;
+}
+
+sub jsMath_converted {
     my $texstring=shift;
-    my $xmlstring;
-    if ($ENV{'browser.mathml'}) {
-      $xmlstring=&tth::ttm($$texstring);
-      $xmlstring=~s/\<math\>/\<math xmlns=\"\&mathns\;\"\>/g;
-      $xmlstring=~s/\<br\>/\<br\/\>/g;
-      $xmlstring=~s/\<p\>/\<p\>\<\/p\>/g;
-      $errorstring.=&tth::ttmerror();
-  } else {
-      $xmlstring=&tth::tth($$texstring);
-      $errorstring.=&tth::ttherror();
-  }
-  return $xmlstring;
-}
-
-# ====================================================================== Footer
-
-sub footer {
-  my $xmlstring='';
-  if ($ENV{'request.state'} eq 'construct') {
-      $xmlstring.='<address>'.$errorstring.'</address>';
-  } else {
-      &Apache::lonmsg::author_res_msg($ENV{'request.filename'},$errorstring);
-  }
-# -------------------------------------------------------------------- End Body
-  $xmlstring.='</html>';
-  return $xmlstring;
+    my $tag='span';
+    if (&displaystyle($texstring)) { $tag='div'; }
+    &clean_out_math_mode($texstring);
+    return &jsMath_header().
+	'<'.$tag.' class="math">'.$$texstring.'</'.$tag.'>';
+}
+
+{
+    my $jsMath_sent_header;
+    sub jsMath_reset {
+	$jsMath_sent_header=0;
+    }
+    sub jsMath_header {
+	return '' if $jsMath_sent_header;
+	$jsMath_sent_header=1;
+	return
+            '<script type="text/javascript">
+                     function NoFontMessage () {}
+                   </script>'."\n".
+	    '<script type="text/javascript" src="/adm/jsMath/jsMath.js"></script>'."\n";
+    }
+    sub jsMath_process {
+	return '' if !$jsMath_sent_header;
+	return '<script type="text/javascript">jsMath.Process()</script>';
+    }
 }
 
+sub init_math_support {
+    &init_tth();
+    &Apache::lontexconvert::jsMath_reset();
+    if ($env{'environment.texengine'} eq 'jsMath' ||
+	$env{'form.texengine'}        eq 'jsMath' ) {
+	return &Apache::lontexconvert::jsMath_header();
+    }
+    return;
+}
+
+sub mimetex_converted {
+    my $texstring=shift;
+    my $displaystyle=&displaystyle($texstring);
+
+    &clean_out_math_mode($texstring);
+
+    if ($displaystyle) {
+	$$texstring='\\displaystyle \\Large '.$$texstring;
+    }
+    my $result='<img src="/cgi-bin/mimetex.cgi?'.&Apache::lonnet::escape($$texstring).'" />';
+    if ($displaystyle) {
+	$result='<center>'.$result.'</center>';
+    }
+    return $result;
+}
+
+sub converted {
+    my ($string,$mode)=@_;
+    if ($mode eq '') { $mode=$env{'environment.texengine'}; }
+    if ($mode =~ /tth/i) {
+	return &tth_converted($string);
+    } elsif ($mode =~ /jsmath/i) {
+	return &jsMath_converted($string);
+    } elsif ($mode =~ /mimetex/i) {
+	return &mimetex_converted($string);
+    }
+    return &tth_converted($string);
+}
+
+# ------------------------------------------------------------ Message display
+
+sub to_convert {
+    my ($string) = @_;
+    $string=~s/\<br\s*\/?\>/ /gs;
+#    $string=~s/\s/ /gs;
+    $string=&HTML::Entities::decode($string);
+    return &converted(\$string);
+}
+
+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 $iconpath=$Apache::lonnet::perlvar{'lonIconsURL'};
+    foreach (keys %smileys) {
+	$expression=~s/$_/\<img src="$iconpath\/$smileys{$_}.gif" \/\>/gs; 
+    }
+    return $expression;
+}
+
+sub msgtexconverted {
+    my ($message,$email) = @_;
+    $errorstring='';
+    &init_tth();
+    my $outmessage='';
+    my $tex=0;
+    foreach (split(/(?:\&lt\;|\<)\/*m\s*(?:\&gt\;|\>)/i,$message)) {
+	if ($tex) {
+	    if ($email) {
+		$outmessage.='</pre><tt>'.&to_convert($_).'</tt><pre>'; $tex=0;
+	    } else {
+		$outmessage.=&to_convert($_); $tex=0;
+	    }
+	} else {
+            $outmessage.=&smiley($_); $tex=1;
+	}
+    }
+    $message=$outmessage; $outmessage=''; $tex=0;
+    foreach (split(/(?:\&lt\;|\<)\/*algebra\s*(?:\&gt\;|\>)/i,$message)) {
+	if ($tex) {
+	    if ($email) {
+		$outmessage.='</pre><tt>'.&algebra($_,'web').'</tt><pre>'; $tex=0;
+	    } else {
+		$outmessage.=&algebra($_,'web'); $tex=0;
+	    }
+	} else {
+            $outmessage.=$_; $tex=1;
+	}
+    }
+    if (wantarray) {
+	return ($outmessage,$errorstring);
+    } else {
+	return $outmessage.$errorstring;
+    }
+}
+
+sub algebra {
+    use AlgParser;
+
+    my ($string,$target,$style)=@_;
+    my $parser = new AlgParserWithImplicitExpand;
+    $string=&prepare_algebra($string);
+    my $ret = $parser->parse($string);
+    my $result='['.&mt('Algebra unconverted due to previous errors').']';
+    if ( ref($ret) ) {
+	#$parser->tostring();
+	$parser->normalize();
+	my $latex=$parser->tolatex();
+	$latex=&postprocess_algebra($latex);
+	if ($style eq 'display') {
+	    $latex='$$'.$latex.'$$x';
+	} else {
+	    # style is 'inline'
+	    $latex='\\ensuremath{'.$latex.'}';
+	}
+	if ($target eq 'web' || $target eq 'analyze') {
+	    $result = &converted(\$latex);
+	} else {
+	    $result = $latex;
+	}
+    } else {
+	&Apache::lonxml::error($parser->{'htmlerror'});
+    }
+}
+
+sub prepare_algebra {
+    my ($string)=@_;
+
+    # makes the decision about what is a minus sign easier supposedly
+    $string =~ s/(\<\>|\<\=|\>\=[\=\>\<] *)-/$1 zeroplace -/g;
+
+    return $string;
+}
+
+sub postprocess_algebra {
+    my ($string)=@_;
+    
+    # moodle had these and I don't know why, ignoring them for now
+    # $string =~s/\\fun/ /g;
+
+    # remove the extra () in the denominator of a \frac
+    $string =~s/\\frac{(.+?)}{\\left\((.+?)\\right\)}/\\frac{$1}{$2}/gs;
+    
+    # sqrt(3,4) means the 4 root of 3
+    $string =~s/\\sqrt{([^,]+),([^\}]+)}/\\sqrt[$2]{$1}/gs;
+
+    # log(3,4) means the log base 4 of 3
+    $string =~s/\\log\\left\((.+?),(.+?)\\right\)/\\log_{$2}\\left($1\\right)/gs;
+
+    # log(3,4) means the log base 4 of 3
+    $string =~s/\\((?:sin|cos|tan|sec|csc|cot)(?:h)?)\\left\((.+?),(.+?)\\right\)/\\$1^{$3}\\left($2\\right)/gs;
+
+    # int(3,a,b) integral from a to b of 3
+    $string =~s/\\int\\left\((.+?),(.+?),(.+?)\\right\)/\\int_{$2}^{$3}\\left($1\\right)/gs;
+
+    # int( ... dx) -> ...
+    $string =~s/\\int\\left\((.+?)d[a-z]\\right\)/$1/gs;
+
+    # 
+    $string =~s/\\lim\\left\((.+?),(.+?),(.+?)\\right\)/\\lim_{$2\\to $3}$1/gs;
+    return $string;
+}
 1;
 __END__