C4/TTParser.pm

   1 # Copyright Tamil 2011
   2 #
   3 # This file is part of Koha.
   4 #
   5 # Koha is free software; you can redistribute it and/or modify it
   6 # under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 3 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # Koha is distributed in the hope that it will be useful, but
  11 # WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with Koha; if not, see <http://www.gnu.org/licenses>.
  17
  18 #simple parser for HTML with Template Toolkit directives. Tokens are put into @tokens and are accesible via next_token and peep_token
  19 package C4::TTParser;
  20 use base qw(HTML::Parser);
  21 use C4::TmplToken;
  22 use strict;
  23 use warnings;
  24
  25 #seems to be handled post tokenizer
  26 ##hash where key is tag we are interested in and the value is a hash of the attributes we want
  27 #my %interesting_tags = (
  28 #    img => { alt => 1 },
  29 #);
  30
  31 #tokens found so far (used like a stack)
  32 my ( @tokens );
  33
  34 #shiftnext token or undef
  35 sub next_token{
  36     return shift @tokens;
  37 }
  38
  39 #unshift token back on @tokens
  40 sub unshift_token{
  41     my $self = shift;
  42     unshift @tokens, shift;
  43 }
  44
  45 #have a peep at next token
  46 sub peep_token{
  47     return $tokens[0];
  48 }
  49
  50 #wrapper for parse
  51 #please use this method INSTEAD of the HTML::Parser->parse_file method (and HTML::Parser->parse)
  52 #signature build_tokens( self, filename)
  53 sub build_tokens{
  54     my ($self, $filename) = @_;
  55     $self->{filename} = $filename;
  56     $self->handler(start => "start", "self, line, tagname, attr, text"); #signature is start( self, linenumber, tagname, hash of attributes, original text )
  57     $self->handler(text => "text", "self, line, text, is_cdata"); #signature is text( self, linenumber, original text, is_cdata )
  58     $self->handler(end => "end", "self, line, tag, attr, text"); #signature is end( self, linenumber, tagename, original text )
  59     $self->handler(declaration => "declaration", "self, line, text, is_cdata"); # declaration
  60     $self->handler(comment => "comment", "self, line, text, is_cdata"); # comments
  61     $self->handler(process => "process", "self, line, text, is_cdata"); # processing statement <?...?>
  62 #    $self->handler(default => "default", "self, line, text, is_cdata"); # anything else
  63     $self->marked_sections(1); #treat anything inside CDATA tags as text, should really make it a C4::TmplTokenType::CDATA
  64     $self->unbroken_text(1); #make contiguous whitespace into a single token (can span multiple lines)
  65     open(my $fh, "<:encoding(utf8)", $filename) || die "Cannot open $filename ($!)";
  66     $self->parse_file($fh);
  67     return $self;
  68 }
  69
  70 #handle parsing of text
  71 sub text{
  72     my $self = shift;
  73     my $line = shift;
  74     my $work = shift; # original text
  75     my $is_cdata = shift;
  76     while($work){
  77         # if there is a template_toolkit tag
  78         if( $work =~ m/\[%.*?%\]/ ){
  79             #everything before this tag is text (or possibly CDATA), add a text token to tokens if $`
  80             if( $` ){
  81                 my $t = C4::TmplToken->new( $`, ($is_cdata? C4::TmplTokenType::CDATA : C4::TmplTokenType::TEXT), $line, $self->{filename} );
  82                 push @tokens, $t;
  83             }
  84
  85             #the match itself is a DIRECTIVE $&
  86             my $t = C4::TmplToken->new( $&, C4::TmplTokenType::DIRECTIVE, $line, $self->{filename} );
  87             push @tokens, $t;
  88
  89             # put work still to do back into work
  90             $work = $' ? $' : 0;
  91         } else {
  92             # If there is some left over work, treat it as text token
  93             my $t = C4::TmplToken->new( $work, ($is_cdata? C4::TmplTokenType::CDATA : C4::TmplTokenType::TEXT), $line, $self->{filename} );
  94
  95             push @tokens, $t;
  96             last;
  97         }
  98     }
  99 }
 100
 101 sub declaration {
 102     my $self = shift;
 103     my $line = shift;
 104     my $work = shift; #original text
 105     my $is_cdata = shift;
 106     my $t = C4::TmplToken->new( $work, ($is_cdata? C4::TmplTokenType::CDATA : C4::TmplTokenType::TEXT), $line, $self->{filename} );
 107     push @tokens, $t;
 108 }
 109
 110 sub comment {
 111     my $self = shift;
 112     my $line = shift;
 113     my $work = shift; #original text
 114     my $is_cdata = shift;
 115     my $t = C4::TmplToken->new( $work, ($is_cdata? C4::TmplTokenType::CDATA : C4::TmplTokenType::TEXT), $line, $self->{filename} );
 116     push @tokens, $t;
 117 }
 118
 119 sub process {
 120     my $self = shift;
 121     my $line = shift;
 122     my $work = shift; #original text
 123     my $is_cdata = shift;
 124     my $t = C4::TmplToken->new( $work, ($is_cdata? C4::TmplTokenType::CDATA : C4::TmplTokenType::TEXT), $line, $self->{filename} );
 125     push @tokens, $t;
 126 }
 127
 128 sub default {
 129     my $self = shift;
 130     my $line = shift;
 131     my $work = shift; #original text
 132     my $is_cdata = shift;
 133     my $t = C4::TmplToken->new( $work, ($is_cdata? C4::TmplTokenType::CDATA : C4::TmplTokenType::TEXT), $line, $self->{filename} );
 134     push @tokens, $t;
 135 }
 136
 137
 138 #handle opening html tags
 139 sub start{
 140     my $self = shift;
 141     my $line = shift;
 142     my $tag = shift;
 143     my $hash = shift; #hash of attr/value pairs
 144     my $text = shift; #original text
 145     my $t = C4::TmplToken->new( $text, C4::TmplTokenType::TAG, $line, $self->{filename});
 146     my %attr;
 147     # tags seem to be uses in an 'interesting' way elsewhere..
 148     for my $key( %$hash ) {
 149         next unless defined $hash->{$key};
 150         if ($key eq "/"){
 151             $attr{+lc($key)} = [ $key, $hash->{$key}, $key."=".$hash->{$key}, 1 ];
 152             }
 153         else {
 154         $attr{+lc($key)} = [ $key, $hash->{$key}, $key."=".$hash->{$key}, 0 ];
 155             }
 156     }
 157     $t->set_attributes( \%attr );
 158     push @tokens, $t;
 159 }
 160
 161 #handle closing html tags
 162 sub end{
 163     my $self = shift;
 164     my $line = shift;
 165     my $tag = shift;
 166     my $hash = shift;
 167     my $text = shift;
 168     # what format should this be in?
 169     my $t = C4::TmplToken->new( $text, C4::TmplTokenType::TAG, $line, $self->{filename} );
 170     my %attr;
 171     # tags seem to be uses in an 'interesting' way elsewhere..
 172     for my $key( %$hash ) {
 173         next unless defined $hash->{$key};
 174         $attr{+lc($key)} = [ $key, $hash->{$key}, $key."=".$hash->{$key}, 0 ];
 175     }
 176     $t->set_attributes( \%attr );
 177     push @tokens, $t;
 178 }
 179
 180 1;