- changed default colors for syntax coloring

- disabled syntax coloring for texts larger than 20KB (too slow)
- added alot of comments to the syntax coloring code

1 files changed, 61 insertions, 43 deletions

diff --git a/Source/CMTextView.m b/Source/CMTextView.m
index 12b253da..cd00cafb 100644
--- a/Source/CMTextView.m
+++ b/Source/CMTextView.m
@@ -25,7 +25,7 @@
 #import "SPStringAdditions.h"
 
 /*
-all the extern variables and prototypes required for flex (syntax highlighting)
+all the extern variables and prototypes required for flex (used for syntax highlighting)
 */
 #import "tokens.h"
 extern int yylex();
@@ -84,7 +84,10 @@ YY_BUFFER_STATE yy_scan_string (const char *);
 }
 
 
-
+/*
+List of keywords for autocompletion. If you add a keyword here,
+it should also be added to the flex file tokens.l
+*/
 -(NSArray *)keywords {
 	return [NSArray arrayWithObjects:
 	@"ADD",
@@ -374,62 +377,77 @@ sets self as delegate for the textView's textStorage to enable syntax highlighti
 
 - (void)textStorageDidProcessEditing:(NSNotification *)notification
 /*
-performs syntax highlighting
-this method recolors the entire text on every keypress. for a single sql query,
-that should be no problem, but it could be a nuisance when editing large sql queries
-*/
+ performs syntax highlighting
+ This method recolors the entire text on every keypress. For performance reasons, this function does
+ nothing if the text is more than a few KB.
+ 
+ The main bottleneck is the [NSTextStorage addAttribute:value:range:] method - the parsing itself is really fast!
+ 
+ Some sample code from Andrew Choi ( http://members.shaw.ca/akochoi-old/blog/2003/11-09/index.html#3 ) has been reused.
+ */
 {
     NSTextStorage *textStore = [notification object];
     
     //make sure that the notification is from the correct textStorage object
-    if (textStore==[self textStorage])
-    {
+    if (textStore!=[self textStorage]) return;
     
-        NSColor *reservedColor = [NSColor blueColor];
-        NSColor *quoteColor    = [NSColor grayColor];
-        NSColor *commentColor  = [NSColor redColor ];
-        
-        NSString *string = [textStore string];
-        unsigned int length = [string length];
-        int token;
-        NSRange textRange, tokenRange;
-        
-        textRange = NSMakeRange(0, length);
-        
-        //first remove the old colors
-        [textStore removeAttribute:NSForegroundColorAttributeName range:textRange];
-
-        //initialise flex
-        yyuoffset = 0; yyuleng = 0;
-        yy_switch_to_buffer(yy_scan_string([[textStore string] UTF8String]));
-
-        //now loop through all the tokens
-        while (token=yylex()){
-            tokenRange = NSMakeRange(yyuoffset, yyuleng);  //convert the result from flex to an NSRange
-            tokenRange = NSIntersectionRange(tokenRange, textRange); // make sure that tokenRange is valid (and therefore within textRange)
-                                                                     // otherwise a bug in the lex code could cause the the TextView to crash
-            
-            switch (token) {
+    
+    NSColor *commentColor   = [NSColor colorWithDeviceRed:0.000 green:0.455 blue:0.000 alpha:1.000];
+    NSColor *quoteColor     = [NSColor colorWithDeviceRed:0.769 green:0.102 blue:0.086 alpha:1.000];
+    NSColor *keywordColor   = [NSColor colorWithDeviceRed:0.200 green:0.250 blue:1.000 alpha:1.000];
+    
+    NSColor *tokenColor;
+    
+    int token;
+    NSRange textRange, tokenRange;
+    
+    textRange = NSMakeRange(0, [textStore length]);
+    
+    //don't color texts longer than about 20KB. would be too slow
+    if (textRange.length > 20000) return; 
+    
+    //first remove the old colors
+    [textStore removeAttribute:NSForegroundColorAttributeName range:textRange];
+    
+    
+    //initialise flex
+    yyuoffset = 0; yyuleng = 0;
+    yy_switch_to_buffer(yy_scan_string([[textStore string] UTF8String]));
+    
+    //now loop through all the tokens
+    while (token=yylex()){
+        switch (token) {
             case SPT_SINGLE_QUOTED_TEXT:
             case SPT_DOUBLE_QUOTED_TEXT:
-                [textStore addAttribute: NSForegroundColorAttributeName
-                                  value: quoteColor
-                                  range: tokenRange ];
+                tokenColor = quoteColor;
                 break;
             case SPT_RESERVED_WORD:
-                [textStore addAttribute: NSForegroundColorAttributeName
-                                  value: reservedColor
-                                  range: tokenRange ];
+                tokenColor = keywordColor;
                 break;
             case SPT_COMMENT:
-                [textStore addAttribute: NSForegroundColorAttributeName
-                                  value: commentColor
-                                  range: tokenRange ];
+                tokenColor = commentColor;
                 break;
-        }}
+            default:
+                tokenColor = nil;
+        }
+        
+        if (!tokenColor) continue;
+        
+        tokenRange = NSMakeRange(yyuoffset, yyuleng);
+        
+        // make sure that tokenRange is valid (and therefore within textRange)
+        // otherwise a bug in the lex code could cause the the TextView to crash
+        tokenRange = NSIntersectionRange(tokenRange, textRange); 
+        if (!tokenRange.length) continue;
+        
+        [textStore addAttribute: NSForegroundColorAttributeName
+                          value: tokenColor
+                          range: tokenRange ];
         
     }
+    
 }
 
 
+
 @end