angelovcom.net

Renderer.php (6813B)

---

 <?php
 /**
  * A class to render Diffs in different formats.
  *
  * This class renders the diff in classic diff format. It is intended that
  * this class be customized via inheritance, to obtain fancier outputs.
  *
  * Copyright 2004-2010 The Horde Project (http://www.horde.org/)
  *
  * See the enclosed file COPYING for license information (LGPL). If you did
  * not receive this file, see http://opensource.org/licenses/lgpl-license.php.
  *
  * @package Text_Diff
  */
 class Text_Diff_Renderer {
 
     /**
      * Number of leading context "lines" to preserve.
      *
      * This should be left at zero for this class, but subclasses may want to
      * set this to other values.
      */
     var $_leading_context_lines = 0;
 
     /**
      * Number of trailing context "lines" to preserve.
      *
      * This should be left at zero for this class, but subclasses may want to
      * set this to other values.
      */
     var $_trailing_context_lines = 0;
 
     /**
      * Constructor.
      */
     function __construct( $params = array() )
     {
         foreach ($params as $param => $value) {
             $v = '_' . $param;
             if (isset($this->$v)) {
                 $this->$v = $value;
             }
         }
     }
 
 	/**
 	 * PHP4 constructor.
 	 */
 	public function Text_Diff_Renderer( $params = array() ) {
 		self::__construct( $params );
 	}
 
     /**
      * Get any renderer parameters.
      *
      * @return array  All parameters of this renderer object.
      */
     function getParams()
     {
         $params = array();
         foreach (get_object_vars($this) as $k => $v) {
             if ($k[0] == '_') {
                 $params[substr($k, 1)] = $v;
             }
         }
 
         return $params;
     }
 
     /**
      * Renders a diff.
      *
      * @param Text_Diff $diff  A Text_Diff object.
      *
      * @return string  The formatted output.
      */
     function render($diff)
     {
         $xi = $yi = 1;
         $block = false;
         $context = array();
 
         $nlead = $this->_leading_context_lines;
         $ntrail = $this->_trailing_context_lines;
 
         $output = $this->_startDiff();
 
         $diffs = $diff->getDiff();
         foreach ($diffs as $i => $edit) {
             /* If these are unchanged (copied) lines, and we want to keep
              * leading or trailing context lines, extract them from the copy
              * block. */
             if (is_a($edit, 'Text_Diff_Op_copy')) {
                 /* Do we have any diff blocks yet? */
                 if (is_array($block)) {
                     /* How many lines to keep as context from the copy
                      * block. */
                     $keep = $i == count($diffs) - 1 ? $ntrail : $nlead + $ntrail;
                     if (count($edit->orig) <= $keep) {
                         /* We have less lines in the block than we want for
                          * context => keep the whole block. */
                         $block[] = $edit;
                     } else {
                         if ($ntrail) {
                             /* Create a new block with as many lines as we need
                              * for the trailing context. */
                             $context = array_slice($edit->orig, 0, $ntrail);
                             $block[] = new Text_Diff_Op_copy($context);
                         }
                         /* @todo */
                         $output .= $this->_block($x0, $ntrail + $xi - $x0,
                                                  $y0, $ntrail + $yi - $y0,
                                                  $block);
                         $block = false;
                     }
                 }
                 /* Keep the copy block as the context for the next block. */
                 $context = $edit->orig;
             } else {
                 /* Don't we have any diff blocks yet? */
                 if (!is_array($block)) {
                     /* Extract context lines from the preceding copy block. */
                     $context = array_slice($context, count($context) - $nlead);
                     $x0 = $xi - count($context);
                     $y0 = $yi - count($context);
                     $block = array();
                     if ($context) {
                         $block[] = new Text_Diff_Op_copy($context);
                     }
                 }
                 $block[] = $edit;
             }
 
             if ($edit->orig) {
                 $xi += count($edit->orig);
             }
             if ($edit->final) {
                 $yi += count($edit->final);
             }
         }
 
         if (is_array($block)) {
             $output .= $this->_block($x0, $xi - $x0,
                                      $y0, $yi - $y0,
                                      $block);
         }
 
         return $output . $this->_endDiff();
     }
 
     function _block($xbeg, $xlen, $ybeg, $ylen, &$edits)
     {
         $output = $this->_startBlock($this->_blockHeader($xbeg, $xlen, $ybeg, $ylen));
 
         foreach ($edits as $edit) {
             switch (strtolower(get_class($edit))) {
             case 'text_diff_op_copy':
                 $output .= $this->_context($edit->orig);
                 break;
 
             case 'text_diff_op_add':
                 $output .= $this->_added($edit->final);
                 break;
 
             case 'text_diff_op_delete':
                 $output .= $this->_deleted($edit->orig);
                 break;
 
             case 'text_diff_op_change':
                 $output .= $this->_changed($edit->orig, $edit->final);
                 break;
             }
         }
 
         return $output . $this->_endBlock();
     }
 
     function _startDiff()
     {
         return '';
     }
 
     function _endDiff()
     {
         return '';
     }
 
     function _blockHeader($xbeg, $xlen, $ybeg, $ylen)
     {
         if ($xlen > 1) {
             $xbeg .= ',' . ($xbeg + $xlen - 1);
         }
         if ($ylen > 1) {
             $ybeg .= ',' . ($ybeg + $ylen - 1);
         }
 
         // this matches the GNU Diff behaviour
         if ($xlen && !$ylen) {
             $ybeg--;
         } elseif (!$xlen) {
             $xbeg--;
         }
 
         return $xbeg . ($xlen ? ($ylen ? 'c' : 'd') : 'a') . $ybeg;
     }
 
     function _startBlock($header)
     {
         return $header . "\n";
     }
 
     function _endBlock()
     {
         return '';
     }
 
     function _lines($lines, $prefix = ' ')
     {
         return $prefix . implode("\n$prefix", $lines) . "\n";
     }
 
     function _context($lines)
     {
         return $this->_lines($lines, '  ');
     }
 
     function _added($lines)
     {
         return $this->_lines($lines, '> ');
     }
 
     function _deleted($lines)
     {
         return $this->_lines($lines, '< ');
     }
 
     function _changed($orig, $final)
     {
         return $this->_deleted($orig) . "---\n" . $this->_added($final);
     }
 
 }