Merge pull request #545 from splitbrain/snippet_fixes

Snippet fixes

inc/fulltext.php

@@ -333,7 +333,7 @@ function ft_snippet($id,$highlight){
                 $pre = min($pre,100-$post);
             } else if ($post>50) {
                 $post = min($post, 100-$pre);
-            } else {
+            } else if ($offset == 0) {
                 // both are less than 50, means the context is the whole string
                 // make it so and break out of this loop - there is no need for the
                 // complex snippet calculations
@@ -354,12 +354,12 @@ function ft_snippet($id,$highlight){
             }
 
             // set $offset for next match attempt
-            //   substract strlen to avoid splitting a potential search success,
-            //   this is an approximation as the search pattern may match strings
-            //   of varying length and it will fail if the context snippet
-            //   boundary breaks a matching string longer than the current match
-            $utf8_offset = $utf8_idx + $post;
-            $offset = $idx + strlen(utf8_substr($text,$utf8_idx,$post));
+            // continue matching after the current match
+            // if the current match is not the longest possible match starting at the current offset
+            // this prevents further matching of this snippet but for possible matches of length
+            // smaller than match length + context (at least 50 characters) this match is part of the context
+            $utf8_offset = $utf8_idx + $utf8_len;
+            $offset = $idx + strlen(utf8_substr($text,$utf8_idx,$utf8_len));
             $offset = utf8_correctIdx($text,$offset);
         }