--- loncom/xml/lontexconvert.pm 2001/11/29 19:03:58 1.4 +++ loncom/xml/lontexconvert.pm 2018/04/23 18:59:28 1.121 @@ -1,7 +1,7 @@ # The LearningOnline Network with CAPA # TeX Conversion Module # -# $Id: lontexconvert.pm,v 1.4 2001/11/29 19:03:58 www Exp $ +# $Id: lontexconvert.pm,v 1.121 2018/04/23 18:59:28 raeburn Exp $ # # Copyright Michigan State University Board of Trustees # @@ -36,73 +36,658 @@ # The C source of the Code may not be distributed by the Licensee # to any other parties under any circumstances. # -# 05/29/00,05/30,10/11,10/20 Gerd Kortemeyer -# 05/03/2001 Scott Harrison -# 5/4 Gerd Kortemeyer package Apache::lontexconvert; use strict; -use tth; +use tth(); use vars qw($errorstring); -use Apache::lonmsg; -use Apache::lonxml; +#use Apache::lonxml(); +use Apache::lonlocal; +use Apache::lonnet; +use lib '/home/httpd/lib/perl/'; +use LONCAPA; +use URI::Escape; +use IO::Socket::INET; + + +# +# Table of substitutions to unicode characters. +# + +my %unicode_harpoons = ( + '\rightleftharpoons' => 0x21cc, + ); + +my %unicode_translations = ( + +# Brackets - unicode for browsers/OS which support it. + + '' => 0x23a1, + '' => 0x23a2, + '' => 0x23a3, + '' => 0x23a4, + '' => 0x23a5, + '' => 0x23a6, + +# Parens - unicode for browsers/OS which support it + + '' => 0x239b, + '' => 0x239c, + '' => 0x239d, + '' => 0x239e, + '' => 0x239f, + '' => 0x23a0, + +); + +my %ascii_8bit_translations = ( + +# Brackets - pure 8-bit ascii ugliness for browsers/OS which can't handle unicode + + '' => 0x5b, + '' => 0x5b, # '[' + '' => 0x5b, + '' => 0x5d, # ']' + '' => 0x5d, + '' => 0x5d, + +# Parens - pure 8-bit ascii ugliness for browsers/OS which can't handle unicode + + '' => 0x28, + '' => 0x28, # '(' + '' => 0x28, + '' => 0x29, + '' => 0x29, # '(' + '' => 0x29, + +); + +## +# Utility to convert elements of a string to unicode: +# +# @param input - Input string +# @param pattern - Pattern to convert +# @param unicode - Unicode to substitute for pattern. +# +# @return string - resulting string. +# +sub unicode_subst { + my ($input, $pattern, $unicode) = @_; + + my $char = pack('U', $unicode); + + $input =~ s/$pattern/$char/g; + + return $input; +} # ====================================================================== Header -sub header { - $errorstring=''; - my $time=time; - if ($ENV{'browser.mathml'}) { - &tth::ttminit(); - } else { - &tth::tthinit(); - } - return &Apache::lonxml::xmlbegin(). - &Apache::lonxml::fontsettings(). - "\n\n". - &Apache::lonxml::registerurl(). - "\n\n"; +sub init_tth { + my $options=$env{'course.'.$env{'request.course.id'}.'.tthoptions'}; + if ($options =~ /\S/) { + $options = ' '.$options; + } else { + undef($options); + } + if ($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 { +$Apache::lontexconvert::messedup=0; + + +sub convert_real { + my ($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($$texstring); + $xmlstring=~s/\/\/g; + $xmlstring=~s/\/\/g; + $xmlstring=~s/\/\\<\/p\>/g; + $errorstring.=&tth::ttmerror(); + } else { + $xmlstring=&tth::tth($$texstring); + $errorstring.=&tth::ttherror(); + $xmlstring=~s---g; + } + $xmlstring=~s/^\s*\
unicode equivalents to render reliably + # in browsers. %unicode_translations and %unicode_harpoons are tables of + # string->substitution which we now apply. (%ascii_8bit_translations used + # instead for Windows XP and mobile devices. + + my $use_ascii; + if ($env{'browser.os'} eq 'win') { + if (($env{'browser.osversion'}) && ($env{'browser.osversion'} < 6.0)) { + $use_ascii = 1; + } + } + if ($env{'browser.mobile'}) { + $use_ascii = 1; + } + + foreach my $pattern (keys(%unicode_translations)) { + my $unicode = $unicode_translations{$pattern}; + if ($use_ascii) { + $unicode = $ascii_8bit_translations{$pattern}; + } + $xmlstring = &unicode_subst($xmlstring, $pattern, $unicode); + } + + foreach my $pattern (keys(%unicode_harpoons)) { + $xmlstring = &unicode_subst($xmlstring, $pattern, $unicode_harpoons{$pattern}); + } + + 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)=@_; + $$texstring=~s/(?/\/g; - $xmlstring=~s/\/\/g; - $xmlstring=~s/\/\\<\/p\>/g; - $errorstring.=&tth::ttmerror(); - } else { - $xmlstring=&tth::tth($$texstring); - $errorstring.=&tth::ttherror(); - } - return $xmlstring; -} - -# ====================================================================== Footer - -sub footer { - my $xmlstring=''; - if ($ENV{'request.state'} eq 'construct') { - $xmlstring.='
'.$errorstring.'
'; - } else { - &Apache::lonmsg::author_res_msg($ENV{'request.filename'},$errorstring); - } -# -------------------------------------------------------------------- End Body - $xmlstring.=&Apache::lonxml::xmlend(); - return $xmlstring; + my ($tag,$startspan,$endspan); + $tag='math/tex;'; + if (&displaystyle($texstring)) { + $tag='math/tex; mode=display'; + $startspan=''; + $endspan=''; + } else { + $startspan=''; + $endspan=''; + } + &clean_out_math_mode($texstring); + return &MathJax_header().$startspan. + ''.$endspan; +} + +{ + #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 + ''."\n"; + } + #sub MathJax_process { + # my $state = pop(@MathJax_sent_header); + # return '' if !$state; + # return "\n". + # ''."\n"; + #} + #sub MathJax_state { + # my ($level) = @_; + # return $MathJax_sent_header[$level]; + #} +} + +sub tex_engine { + if (exists($env{'form.texengine'})) { + if ($env{'form.texengine'} ne '') { + if (lc($env{'form.texengine'}) eq 'jsmath') { + return 'MathJax'; + } + return $env{'form.texengine'}; + } + } + if ($env{'request.course.id'} + && exists($env{'course.'.$env{'request.course.id'}.'.texengine'})) { + if (lc($env{'course.'.$env{'request.course.id'}.'.texengine'}) eq 'jsmath') { + return 'MathJax'; + } + return $env{'course.'.$env{'request.course.id'}.'.texengine'}; + } + if (exists($env{'environment.texengine'})) { + if (lc($env{'environment.texengine'}) eq 'jsmath') { + return 'MathJax'; + } + return $env{'environment.texengine'}; + } + my $dom = $env{'request.role.domain'} || $env{'user.domain'}; + my %domdefaults = &Apache::lonnet::get_domain_defaults($dom); + if ($domdefaults{'texengine'} ne '') { + return $domdefaults{'texengine'}; + } + return 'MathJax'; +} + +sub init_math_support { + &init_tth(); + &Apache::lontexconvert::MathJax_push(); + if (lc(&tex_engine()) eq 'mathjax') { + return &Apache::lontexconvert::MathJax_header(); + } + return; +} + +sub mimetex_valign { + my ($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 '.$$texstring; + } + my $esc_texstring = &uri_escape($$texstring); + my $valign = &mimetex_valign($esc_texstring); + my $result=''.$alt_string.''; + if ($displaystyle) { + $result='
'.$result.'
'; + } + return $result; +} + +sub converted { + my ($string,$mode)=@_; + if ($mode eq '') { $mode = &tex_engine(); } + if ($mode =~ /tth/i) { + return &tth_converted($string); + } elsif ($mode =~ /jsmath/i) { + return &MathJax_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($string); +} + +# ------------------------------------------------------------ Message display + +sub to_convert { + my ($string) = @_; + &init_tth(); + $string=~s/\/ /gs; +# $string=~s/\s/ /gs; + $string=&HTML::Entities::decode($string); + return &converted(\$string); } +sub smiley { + my $expression=shift; + 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', + '(\<\;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/\/gs; + } + return $expression; +} + +sub msgtexconverted { + my ($message,$email) = @_; + $errorstring=''; + my $outmessage=''; + my $tex=0; + foreach my $fragment (split(/(?:\<\;|\<)\/*m\s*(?:\>\;|\>)/i,$message)) { + if ($tex) { + if ($email) { + $outmessage.=''.&to_convert($fragment).'
';
+		$tex=0;
+	    } else {
+		$outmessage.=&to_convert($fragment);
+		$tex=0;
+	    }
+	} else {
+            $outmessage.=&smiley($fragment);
+	    $tex=1;
+	}
+    }
+    $message=$outmessage; $outmessage=''; $tex=0;
+    foreach my $fragment (split(/(?:\<\;|\<)\/*algebra\s*(?:\>\;|\>)/i,
+				$message)) {
+	if ($tex) {
+        my $algebra = &algebra($fragment, 'web', undef, undef, undef, 'tth');
+	    if ($email) {
+		$outmessage.='
'.$algebra.'
';
+		$tex=0;
+	    } else {
+		$outmessage.=$algebra;
+		$tex=0;
+	    }
+	} else {
+        $outmessage.=$fragment;
+	    $tex=1;
+	}
+    }
+    if (wantarray) {
+	return ($outmessage,$errorstring);
+    } else {
+	return $outmessage.$errorstring;
+    }
+}
+
+sub algebra {
+    use AlgParser;
+    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 $result='['.&mt('Algebra unconverted due to previous errors').']';
+    if ( ref($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') {
+            my $display=&Apache::lonxml::get_param('display',$parstack,$safeeval);
+            $result = &converted(\$latex,$display);
+#	    $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;
+
+    # 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__
 
 
+=pod
+
+=head1 NAME
+
+Apache::lontexconvert;
+
+=head1 SYNOPSIS
+
+Access to tth/ttm
+
+This is part of the LearningOnline Network with CAPA project
+described at http://www.lon-capa.org.
+
+
+=head1 SUBROUTINES
+
+=over
+
+=item init_tth()
+
+Header
+
+=item convert_real()
+
+ we need this routine because &converted can get called from inside
+ of the safespace (through &xmlparse('stuff') 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
+
+=item tth_converted()
+
+
+=item clean_out_math_mode()
+
+
+=item displaystyle()
+
+
+=item MathJax_converted()
+
+=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  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  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:
+
+ 
+     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]
+ 
+
+=item mimetex_converted()
+
+
+=item converted()
+
+
+=item to_convert()
+
+message display
+
+=item smiley()
+
+???
+
+=item msgtexconverted()
+
+=item algebra()
+
+=item prepare_algebra()
+
+=item postprocess_algebra()
 
+=back
 
+=cut