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												require_once 'HTMLPurifier/TagTransform.php';								/**				 * Transforms FONT tags to the proper form (SPAN with CSS styling)				 * 				 * This transformation takes the three proprietary attributes of FONT and				 * transforms them into their corresponding CSS attributes.  These are color,				 * face, and size.				 * 				 * @note Size is an interesting case because it doesn't map cleanly to CSS.				 *       Thanks to				 *       http://style.cleverchimp.com/font_size_intervals/altintervals.html				 *       for reasonable mappings.				 */				class HTMLPurifier_TagTransform_Font extends HTMLPurifier_TagTransform				{				    				    var $transform_to = 'span';				    				    var $_size_lookup = array(				        '0' => 'xx-small',				        '1' => 'xx-small',				        '2' => 'small',				        '3' => 'medium',				        '4' => 'large',				        '5' => 'x-large',				        '6' => 'xx-large',				        '7' => '300%',				        '-1' => 'smaller',				        '-2' => '60%',				        '+1' => 'larger',				        '+2' => '150%',				        '+3' => '200%',				        '+4' => '300%'				    );				    				    function transform($tag, $config, &$context) {				        				        if ($tag->type == 'end') {				            $new_tag = $tag->copy();				            $new_tag->name = $this->transform_to;				            return $new_tag;				        }				        				        $attr = $tag->attr;				        $prepend_style = '';				        				        // handle color transform				        if (isset($attr['color'])) {				            $prepend_style .= 'color:' . $attr['color'] . ';';				            unset($attr['color']);				        }				        				        // handle face transform				        if (isset($attr['face'])) {				            $prepend_style .= 'font-family:' . $attr['face'] . ';';				            unset($attr['face']);				        }				        				        // handle size transform				        if (isset($attr['size'])) {				            // normalize large numbers				            if ($attr['size']{0} == '+' || $attr['size']{0} == '-') {				                $size = (int) $attr['size'];				                if ($size < -2) $attr['size'] = '-2';				                if ($size > 4)  $attr['size'] = '+4';				            } else {				                $size = (int) $attr['size'];				                if ($size > 7) $attr['size'] = '7';				            }				            if (isset($this->_size_lookup[$attr['size']])) {				                $prepend_style .= 'font-size:' .				                  $this->_size_lookup[$attr['size']] . ';';				            }				            unset($attr['size']);				        }				        				        if ($prepend_style) {				            $attr['style'] = isset($attr['style']) ?				                $prepend_style . $attr['style'] :				                $prepend_style;				        }				        				        $new_tag = $tag->copy();				        $new_tag->name = $this->transform_to;				        $new_tag->attr = $attr;				        				        return $new_tag;				        				    }				}