AsyncDrawOperation.m

//
//  NewAsyncDrawOperation.m
//  Textmate-Minimap
//
//  Created by Julian Eberius on 19.03.10.
//  Copyright 2010 Julian Eberius. All rights reserved.
//

#import "AsyncDrawOperation.h"
#import "NSView+Minimap.h"
#import "MinimapView.h"

@interface NSView (TextMate_OakTextView_Only)
- (id)currentStyleSheet;
@end

@interface AsyncDrawOperation (Private_NewAsyncDrawOperation)
- (NSBitmapImageRep*)cropImageRep:(NSBitmapImageRep*)rep ToRect:(NSRect)rect;
- (void)initializeFillColorFromTextView;
- (void)makeCompleteSnapshot;
- (void)makePartialSnapshot;
- (void)partialBackgroundDraw;
- (BOOL)checkCancelled;
- (NSRect)scaleRect:(NSRect)rect withFactor:(float)factor;
@end

@implementation AsyncDrawOperation

- (id)initWithMinimapView:(MinimapView*)mv andMode:(int)md
{
  self = [super init];
    if (self) {
    minimapView = mv;
    mode = md;
    fillColor = nil;
  }
    return self;
}
- (id)initWithMinimapView:(MinimapView*)mv andMode:(int)md andUpdater:(BackgroundUpdater*)upd
{
  self = [self initWithMinimapView:mv andMode:md];
  if (self) {
    updater = upd;
  }
  return self;
}

- (void) dealloc
{
  [super dealloc];
//  [minimapView release];
}

- (void)setPartToDraw:(NSRect)part
{
  partToDraw = part;
}

- (void)main
{
  if ([self isCancelled])
    return;

  switch (mode) {
    case MM_COMPLETE_IMAGE:
      [self makeCompleteSnapshot];
      break;
    case MM_PARTIAL_IMAGE:
      [self makePartialSnapshot];
      break;
    default:
      break;
  }
}

- (void)makePartialSnapshot
{
  //[[minimapView drawLock] lock];
  NSImage* old_image = [minimapView theImage];
  int gutterSize = [minimapView gutterSize];
  NSRect tvBounds = NSMakeRect(gutterSize, 0,
                 [[minimapView textView] croppedBounds].size.width-gutterSize,
                 [[minimapView textView] croppedBounds].size.height);
  NSRect bounds = [minimapView bounds];
  float scaleFactor = bounds.size.width / tvBounds.size.width;
  int h = tvBounds.size.height*scaleFactor;
  NSRect newImageRect = NSMakeRect(0, 0, bounds.size.width, h);
  NSImage* image = [[[NSImage alloc] initWithSize:newImageRect.size] autorelease];
  if ([self checkCancelled])
    return;
  NSRect rectToRedraw = NSMakeRect(tvBounds.origin.x,
                   partToDraw.origin.y/scaleFactor,
                   tvBounds.size.width,
                   partToDraw.size.height/scaleFactor);
  NSImage* drawnPart = [[minimapView textView] snapshotByDrawingInRect:rectToRedraw];
  if ([self checkCancelled])
    return;

  [image lockFocus];
    [fillColor set];
    NSRectFill(NSMakeRect(0, 0, [image size].width, [image size].height));
    // new image is longer or equal
    if (h >= [old_image size].height) {
      [old_image drawInRect:NSMakeRect(0, 0, [image size].width, [old_image size].height)
             fromRect:NSZeroRect
            operation:NSCompositeSourceOver fraction:1.0];
    }
    else {
      [old_image drawInRect:newImageRect
             fromRect:NSMakeRect(0,0, [old_image size].width, [image size].height)
            operation:NSCompositeSourceOver fraction:1.0];
    }

    [drawnPart drawInRect:partToDraw
           fromRect:NSZeroRect
           operation:NSCompositeSourceOver fraction:1.0];
  [image unlockFocus];

  if ([self checkCancelled])
    return;
  [minimapView performSelectorOnMainThread:@selector(asyncDrawFinished:) withObject:image waitUntilDone:YES];

  //[[minimapView drawLock] unlock];
}


- (BOOL)checkCancelled
{
  if ([self isCancelled]) {
    //[[minimapView drawLock] unlock];
    return YES;
  }
  return NO;
}

- (NSRect)scaleRect:(NSRect)rect withFactor:(float)factor
{
  return NSMakeRect(rect.origin.x*factor, rect.origin.y*factor, rect.size.width*factor, rect.size.height*factor);
}

- (void)makeCompleteSnapshot
{
  // [[minimapView drawLock] lock];
  if ([self checkCancelled])
    return;
  NSView* textView = [minimapView textView];
  NSBitmapImageRep* snapshot = [textView snapshot];
  int gutterSize = [minimapView gutterSize];
  NSBitmapImageRep* croppedSnapshot = [self cropImageRep:snapshot
                          ToRect:NSMakeRect(gutterSize, 0, [snapshot size].width-gutterSize, [snapshot size].height)];
  if ([self checkCancelled])
    return;
  NSRect bounds = [minimapView bounds];
  float scaleFactor = bounds.size.width / [croppedSnapshot size].width;
  int h = croppedSnapshot.size.height*scaleFactor;

  NSImage* image = [[[NSImage alloc] initWithSize:NSMakeRect(0, 0, bounds.size.width, h).size] autorelease];

  if ([self checkCancelled])
    return;
  [self initializeFillColorFromTextView];


  [image setFlipped:YES];
  [image lockFocus];
    NSRect imgRect = NSMakeRect(0, 0, bounds.size.width, h);
    [croppedSnapshot drawInRect:imgRect];
  [image unlockFocus];
  [image setFlipped:NO];

  if ([self checkCancelled])
    return;
  [minimapView performSelectorOnMainThread:@selector(asyncDrawFinished:) withObject:image waitUntilDone:YES];
  // [[minimapView drawLock] unlock];
}

/*
 Copy&Pasted from the interwebs for cropping NSBitmapImageReps (used for cropping the gutter from the TextView Snapshots)
 */
- (NSBitmapImageRep*)cropImageRep:(NSBitmapImageRep*)rep ToRect:(NSRect)rect {
  CGImageRef cgImg = CGImageCreateWithImageInRect([rep CGImage], NSRectToCGRect(rect)); NSBitmapImageRep *result = [[NSBitmapImageRep alloc] initWithCGImage:cgImg];

  CGImageRelease(cgImg);
  return [result autorelease];
}

- (void)initializeFillColorFromTextView
{
  id stylesheet = [[minimapView textView] currentStyleSheet];
  NSDictionary* firstEntry = [(NSArray*)stylesheet objectAtIndex:0]; // the first entry seems to always contain the main settings
  NSString* bgColor = [[firstEntry objectForKey:@"settings"] objectForKey:@"background"];
  unsigned aValue = strtoul([[bgColor substringWithRange:NSMakeRange(1, 6)] UTF8String], NULL, 16);
  CGFloat red = ((CGFloat)((aValue & 0xFF0000) >> 16)) / 255.0f;
  CGFloat green = ((CGFloat)((aValue & 0xFF00) >> 8)) / 255.0f;
  CGFloat blue = (CGFloat)(aValue & 0xFF) / 255.0f;
  CGFloat alpha = 1.0;
  if ([bgColor length] == 9) //  if a alpha was given
  {
    unsigned alphaValue = strtoul([[bgColor substringWithRange:NSMakeRange(7, 2)] UTF8String], NULL, 16);
    alpha = (CGFloat)(alphaValue & 0xFF) / 255.0f;
  }
  fillColor = [NSColor colorWithCalibratedRed:red green:green blue:blue alpha:alpha];
}

@end