# Copyright (C) 2005 ILOG http://www.ilog.fr

 # and TWiki Contributors. All Rights Reserved. TWiki Contributors

 # are listed in the AUTHORS file in the root of this distribution.

 # NOTE: Please extend that file, not this notice.

 #

 # This program 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. For

 # more details read LICENSE in the root of the TWiki distribution.

 #

 # This program 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.

 #

 # As per the GPL, removal of this notice is prohibited.

 =pod

 ---+ package WC

 Constants

 =cut

 package WC;

 =pod

 ---++ Generator flags

 | $NO_TML | Flag that gets passed _down_ into generator functions. Constrains output to HTML only. |

 | $NO_BLOCK_TML | Flag that gets passed _down_ into generator functions. Don't generate block TML e.g. tables, lists |

 | $NOP_ALL | Flag that gets passed _down_ into generator functions. NOP all variables and WikiWords. |

 | $BLOCK_TML | Flag passed up from generator functions; set if expansion includes block TML |

 | $VERY_CLEAN | Flag passed to indicate that HTML must be aggressively cleaned (unrecognised or unuseful tags stripped out) |

 | $BR2NL | Flag set to force BR tags to be converted to newlines. |

 | $KEEP_WS | Set to force the generator to keep all whitespace. Otherwise whitespace gets collapsed (as it is when HTML is rendered) |

 | $PROTECTED | In a block marked as PROTECTED |

 | $KEEP_ENTITIES | Don't decode HTML entities |

 =cut

 our ($NO_TML, $NO_HTML, $NO_BLOCK_TML, $NOP_ALL, $BLOCK_TML, $BR2NL);

 our ($CHECKn, $CHECKw, $CHECKs, $NBSP, $NBBR, $TAB, $PON, $POFF, $WS);

 our ($VERY_CLEAN, $PROTECTED, $KEEP_ENTITIES, $KEEP_WS);

 $NO_HTML       = 1 << 0;

 $NO_TML        = 1 << 1;

 $NO_BLOCK_TML  = 1 << 2;

 $NOP_ALL       = 1 << 3;

 $VERY_CLEAN    = 1 << 4;

 $BR2NL         = 1 << 5;

 $KEEP_WS       = 1 << 6;

 $PROTECTED     = 1 << 7;

 $KEEP_ENTITIES = 1 << 8;

 $BLOCK_TML    = $NO_BLOCK_TML;

 my %cc = (

     'NBSP'   => 14, # unbreakable space

     'NBBR'   => 15, # para break required

     'CHECKn' => 16, # require adjacent newline (\n or $NBBR)

     'CHECKs' => 17, # require adjacent space character (' ' or $NBSP)

     'CHECKw' => 18, # require adjacent whitespace (\s|$NBBR|$NBSP)

     'CHECK1' => 19, # start of wiki-word

     'CHECK2' => 20, # end of wiki-word

     'TAB'    => 21, # list indent

     'PON'    => 22, # protect on

     'POFF'   => 23, # protect off

 );

 =pod

 ---++ Forced whitespace

 These single-character shortcuts are used to assert the presence of

 non-breaking whitespace.

 | $NBSP | Non-breaking space |

 | $NBBR | Non-breaking linebreak |

 =cut

 $NBSP   = chr($cc{NBSP});

 $NBBR   = chr($cc{NBBR});

 =pod

 ---++ Inline Assertions

 The generator works by expanding to "decorated" text, where the decorators

 are characters below ' '. These characters act to express format

 requirements - for example, the need to have a newline before some text,

 or the need for a space. The generator sticks this format requirements into

 the text stream, and they are then optimised down to the minimum in a post-

 process.

 | $CHECKn | there must be an adjacent newline (\n or $NBBR) |

 | $CHECKs | there must be an adjacent space (' ' or $NBSP) |

 | $CHECKw | There must be adjacent whitespace (\s or $NBBR or $NBSP) |

 | $CHECK1 | Marks the start of an inline wikiword. |

 | $CHECK2 | Marks the end of an inline wikiword. |

 | $TAB    | Shorthand for an indent level in a list |

 =cut

 $CHECKn = chr($cc{CHECKn});

 $CHECKs = chr($cc{CHECKs});

 $CHECKw = chr($cc{CHECKw});

 $CHECK1 = chr($cc{CHECK1});

 $CHECK2 = chr($cc{CHECK2});

 $TAB    = chr($cc{TAB});

 $PON    = chr($cc{PON});

 $POFF   = chr($cc{POFF});

 $WS     = qr/[$NBSP$NBBR$CHECKn$CHECKs$CHECKw$CHECK1$CHECK2$TAB\s]*/;

 =pod

 ---++ REs

 REs for matching delimiters of wikiwords, must be consistent with TML2HTML.pm

 | $STARTWW | Zero-width match for the start of a wikiword |

 | $ENDWW | Zero-width match for the end of a wikiword |

 | $PROTOCOL | match for a valid URL protocol e.g. http, mailto etc |

 =cut

 sub debugEncode {

     my $string = shift;

     while (my ($k, $v) = each %cc) {

         my $c = chr($v);

         $string =~ s/$c/\%$k/g;

     }

     return $string;

 }

 # Maps of tag types

 our (%SELFCLOSING, $EMPHTAG);

 %SELFCLOSING = (img => 1);

 # Map that specifies tags to be renamed to a canonical name

 %EMPHTAG = (

     b => 'strong',

     i => 'em',

     tt => 'code',

     strong => 'strong',

     em => 'em',

     code => 'code',

 );

 1;