<?php
/**
 * Plugin Color: Sets new colors for text and background.
 * 
 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
 * @author     Christopher Smith <chris@jalakai.co.uk>
 */

// must be run within Dokuwiki
if(!defined('DOKU_INC')) die();

/**
 * All DokuWiki plugins to extend the parser/rendering mechanism
 * need to inherit from this class
 */
class syntax_plugin_color extends DokuWiki_Syntax_Plugin {

    public function getType(){ return 'formatting'; }
    public function getAllowedTypes() { return array('formatting', 'substition', 'disabled'); }   
    public function getSort(){ return 158; }
    public function connectTo($mode) { $this->Lexer->addEntryPattern('<color.*?>(?=.*?</color>)',$mode,'plugin_color'); }
    public function postConnect() { $this->Lexer->addExitPattern('</color>','plugin_color'); }


    /**
     * Handle the match
     */
    public function handle($match, $state, $pos, Doku_Handler $handler){
        switch ($state) {
          case DOKU_LEXER_ENTER :
                list($color, $background) = preg_split("/\//u", substr($match, 6, -1), 2);
                if ($color = $this->_isValid($color)) $color = "color:$color;";
                if ($background = $this->_isValid($background)) $background = "background-color:$background;";
                return array($state, array($color, $background));

          case DOKU_LEXER_UNMATCHED :  return array($state, $match);
          case DOKU_LEXER_EXIT :       return array($state, '');
        }
        return array();
    }

    /**
     * Create output
     */
    public function render($format, Doku_Renderer $renderer, $data) {
        // $data is what the function handle() return'ed.
        if($format == 'xhtml'){
            /** @var Doku_Renderer_xhtml $renderer */
            list($state,$match) = $data;
            switch ($state) {
                case DOKU_LEXER_ENTER :      
                    list($color, $background) = $match;
                    $renderer->doc .= "<span style='$color $background'>"; 
                    break;
                
                case DOKU_LEXER_UNMATCHED :  
                    $renderer->doc .= $renderer->_xmlEntities($match); 
                    break;
                case DOKU_LEXER_EXIT :       
                    $renderer->doc .= "</span>"; 
                    break;
            }
            return true;
        }
        return false;
    }
    
    /**
     * Validate color value $c
     * this is cut price validation - only to ensure the basic format is correct and there is nothing harmful
     * three basic formats  "colorname", "#fff[fff]", "rgb(255[%],255[%],255[%])"
     */
    private function _isValid($c) {
        $c = trim($c);
        
        $pattern = "/^\s*(
            ([a-zA-z]+)|                                #colorname - not verified
            (\#([0-9a-fA-F]{3}|[0-9a-fA-F]{6}))|        #colorvalue
            (rgb\(([0-9]{1,3}%?,){2}[0-9]{1,3}%?\))     #rgb triplet
            )\s*$/x";
        
        if (preg_match($pattern, $c)) return trim($c);
        
        return "";
    }
}