From 5031b7f3c017c054bd8aa3a5462d05d1321e59d7 Mon Sep 17 00:00:00 2001
From: Robert Sesek <rsesek@bluestatic.org>
Date: Sat, 17 Dec 2005 05:07:35 +0000
Subject: [PATCH] Checking in experimental diff system that's been rewritten

---
 includes/svnlib.php | 69 +++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 66 insertions(+), 3 deletions(-)

diff --git a/includes/svnlib.php b/includes/svnlib.php
index ebdceaa..282ab57 100644
--- a/includes/svnlib.php
+++ b/includes/svnlib.php
@@ -851,6 +851,8 @@ class SVNDiff
 	*/
 	function process()
 	{
+		global $viewsvn;
+		
 		$chunk = 0;
 		$indexcounter = null;
 		
@@ -897,7 +899,7 @@ class SVNDiff
 					$delstack = array();
 				}
 				else if ($act == '+')
-				{
+				{		
 					// potential line delta
 					if (count($delstack) > 0)
 					{
@@ -905,8 +907,28 @@ class SVNDiff
 						
 						if ($delta = @$this->fetch_diff_extent($lastline['line'], $content))
 						{
+							//$delta['end'] = $delta['start'] + -$delta['end'];
+							//print_r($delta);
+							//$change = '';
+							if (strlen($lastline['line']) > ($delta['start'] - $delta['end']))
+							{
+								$end = strlen($lastline['line']) + $delta['end'];
+								$viewsvn->debug("RM delta- = " . $end);
+								$change = '{@-' . '-}' . substr($lastline['line'], $delta['start'], $end - $delta['start']) . '{/@-' . '-}';
+								$this->diff["$index"]["$chunk"]["$lastline[INDEX]"]['line'] = substr($lastline['line'], 0, $delta['start']) . $change . substr($lastline['line'], $end);
+							}
+							
+							//$change = '';
+							if (strlen($content) > $delta['start'] - $delta['end'])
+							{
+								$end = strlen($content) + $delta['end'];
+								$viewsvn->debug("MK delta+ = " . $end);
+								$change = '{@+' . '+}' . substr($content, $delta['start'], $end - $delta['start']) . '{/@+' . '+}';
+								$content = substr($content, 0, $delta['start']) . $change . substr($content, $end);
+							}
+							
 							// create two sets of ends for the two contents
-							$delta['endo'] = strlen($lastline['line']) - $delta['end'];
+							/*$delta['endo'] = strlen($lastline['line']) - $delta['end'];
 							$delta['endn'] = strlen($content) - $delta['end'];
 							
 							$diffo = $delta['endo'] - $delta['start'];
@@ -922,7 +944,7 @@ class SVNDiff
 							{
 								$added = substr($content, $delta['start'], $diffn);
 								$content = substr_replace($content, '{@+' . '+}' . $added . '{/@+' . '+}', $delta['start'], $diffn);
-							}
+							}*/
 						}
 					}
 					
@@ -983,6 +1005,47 @@ class SVNDiff
 	* @return	array	Difference of positions
 	*/
 	function fetch_diff_extent($old, $new)
+	{
+		global $viewsvn;
+		
+		$start = 0;
+		$min = min(strlen($old), strlen($new));
+		
+		$viewsvn->debug("min1 = $min");
+		
+		while ($start < $min AND $old{"$start"} == $new{"$start"})
+		{
+			$start++;
+		}
+		
+		$end = -1;
+		$min = $min - $start;
+		
+		$viewsvn->debug("min2 = $min");
+		
+		$viewsvn->debug("checking: " . $old{ strlen($old) + $end } . ' ==  ' . $new{ strlen($new) + $end });
+		
+		while (-$end <= $min AND $old{ strlen($old) + $end } == $new{ strlen($new) + $end })
+		{
+			$end--;
+		}
+		
+		return array('start' => $start, 'end' => $end + 1, 'min' => $min);
+	}
+	
+	/**
+	* Returns the amount of change that occured
+	* between two lines
+	*
+	* @access	private
+	* @deprecated	Use the fetch_diff_extent() function; this one calculates incorrect end deltas
+	*
+	* @param	string	Old line
+	* @param	string	New line
+	*
+	* @return	array	Difference of positions
+	*/
+	function fetch_diff_extent2($old, $new)
 	{
 		$start = 0;
 		$min = min(strlen($old), strlen($new));
-- 
2.22.5