<?php
/**
 * 
 * Block plugin to form paragraphs of text with 2 newlines around it.
 * 
 * @category Solar
 * 
 * @package Solar_Markdown
 * 
 * @author John Gruber <http://daringfireball.net/projects/markdown/>
 * 
 * @author Michel Fortin <http://www.michelf.com/projects/php-markdown/>
 * 
 * @author Paul M. Jones <hide@address.com>
 * 
 * @license http://opensource.org/licenses/bsd-license.php BSD
 * 
 * @version $Id: Paragraph.php 3153 2008-05-05 23:14:16Z pmjones $
 * 
 */
class Solar_Markdown_Plugin_Paragraph extends Solar_Markdown_Plugin
{
    /**
     * 
     * This is a block plugin.
     * 
     * @var bool
     * 
     */
    protected $_is_block = true;
    
    /**
     * 
     * Forms paragraphs from source text.
     * 
     * @param string $text Portion of the Markdown source text.
     * 
     * @return string The transformed XHTML.
     * 
     */
    public function parse($text)
    {   
        // Strip leading and trailing lines:
        $text = preg_replace(array('/\A\n+/', '/\n+\z/'), '', $text);
        
        // split into possible paragraphs
        $grafs = preg_split('/\n{2,}/', $text, -1, PREG_SPLIT_NO_EMPTY);
        
        // Wrap <p> tags around apparent paragraphs.
        foreach ($grafs as $key => $value) {
            if (! $this->_isHtmlToken($value)) {
                // not an HTML token, looks like a paragraph.
                $value = $this->_processSpans($value);
                $value = preg_replace('/^([ \t]*)/', '<p>', $value);
                $value .= "</p>";
                $grafs[$key] = $this->_toHtmlToken($value);
            }
        }
        
        // done!
        return implode("\n\n", $grafs);
    }
}