#import <Cocoa/Cocoa.h>

//#define USEBITMAP

@interface MyView : NSView {
    CGContextRef bitmap;
    unsigned char* data;
    CGImageRef image;

    unsigned long long pixels;
    unsigned long long frames;
}

@property (readonly) unsigned long long pixels;
@property (readonly) unsigned long long frames;

@property(getter=isOpaque, readonly) BOOL opaque;
@property(readonly) BOOL wantsDefaultClipping;

@end

@implementation MyView

- (id)init {
    self = [super initWithFrame:NSMakeRect(0, 0, 1024, 768)];

    //[self setWantsLayer:YES];

    CGColorSpaceRef lut;
    lut = CGDisplayCopyColorSpace(kCGDirectMainDisplay);
    data = malloc(self.frame.size.width * self.frame.size.height * 4);

#ifdef USEBITMAP
    bitmap = CGBitmapContextCreate(data, self.frame.size.width, self.frame.size.height, 8, self.frame.size.width * 4, lut, kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little);
#else
    CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, data, self.frame.size.width * self.frame.size.height * 4, NULL);
    image = CGImageCreate(self.frame.size.width, self.frame.size.height, 8, 32, self.frame.size.width * 4, lut, kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Little, provider, NULL, false, kCGRenderingIntentDefault);
    CGDataProviderRelease(provider);
#endif

    CGColorSpaceRelease(lut);

    [NSTimer scheduledTimerWithTimeInterval:10.0 target:self selector:@selector(onTimeout:) userInfo:nil repeats:NO];

    pixels = 0;
    frames = 0;

    return self;
}

- (void)dealloc {
    free(data);
    [super dealloc];
}

- (unsigned long long)pixels {
    return pixels;
}

- (unsigned long long)frames {
    return frames;
}

- (BOOL)isOpaque {
    return YES;
}

- (BOOL)wantsDefaultClipping {
    return NO;
}

- (void)drawRect:(NSRect)dirtyRect {
    //[super drawRect:dirtyRect];

    CGContextRef gc;
    
    memset(data, rand(), self.frame.size.width * self.frame.size.height * 4);

    gc = [[NSGraphicsContext currentContext] graphicsPort];
    //CGContextSaveGState(gc);

#ifdef USEBITMAP
    image = CGBitmapContextCreateImage(bitmap);
#endif
    CGContextDrawImage(gc, CGRectMake(0, 0, self.frame.size.width, self.frame.size.height), image);
#ifdef USEBITMAP
    CGImageRelease(image);
#endif

    //CGContextRestoreGState(gc);

    frames++;
    pixels += self.frame.size.width * self.frame.size.height;

    [NSTimer scheduledTimerWithTimeInterval:0 target:self selector:@selector(onTimer:) userInfo:nil repeats:NO];
}

- (void)onTimer:(NSTimer*)timer {
     [self setNeedsDisplay:true];
}

- (void)onTimeout:(NSTimer*)timer {
    fprintf(stderr, "Stopping!\n");
    [NSApp terminate:self];
}

@end

@interface MyApp: NSObject <NSApplicationDelegate> {
    struct timeval start, stop;
    struct rusage cpuStart, cpuStop;
}
@end

@implementation MyApp
- (void)applicationDidFinishLaunching:(NSNotification *)notification {
    gettimeofday(&start, NULL);
    getrusage(RUSAGE_SELF, &cpuStart);
}


static size_t doPrefix(long long value, const char *unit,
                     char *buffer, size_t maxlen,
                     unsigned divisor, const char **prefixes,
                     size_t prefixCount) {
double newValue;
size_t prefix, len;

newValue = value;
prefix = 0;
while (newValue >= divisor) {
  if (prefix >= prefixCount)
    break;
  newValue /= divisor;
  prefix++;
}

len = snprintf(buffer, maxlen, "%g %s%s", newValue,
               (prefix == 0) ? "" : prefixes[prefix-1], unit);
buffer[maxlen-1] = '\0';

return len;
}

static const char *siPrefixes[] =
{ "k", "M", "G", "T", "P", "E", "Z", "Y" };
static const char *iecPrefixes[] =
{ "Ki", "Mi", "Gi", "Ti", "Pi", "Ei", "Zi", "Yi" };

size_t siPrefix(long long value, const char *unit,
              char *buffer, size_t maxlen) {
return doPrefix(value, unit, buffer, maxlen, 1000, siPrefixes,
                sizeof(siPrefixes)/sizeof(*siPrefixes));
}

size_t iecPrefix(long long value, const char *unit,
               char *buffer, size_t maxlen) {
return doPrefix(value, unit, buffer, maxlen, 1024, iecPrefixes,
                sizeof(iecPrefixes)/sizeof(*iecPrefixes));
}

- (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender
{
    double realTime, encodeTime;
    double sysSeconds, userSeconds;
    id view;
    char s[1024];

    getrusage(RUSAGE_SELF, &cpuStop);
    gettimeofday(&stop, NULL);

    realTime = (double)stop.tv_sec - start.tv_sec;
    realTime += ((double)stop.tv_usec - start.tv_usec)/1000000.0;

    sysSeconds = (double)(cpuStop.ru_stime.tv_sec -
                          cpuStart.ru_stime.tv_sec);
    sysSeconds += (double)(cpuStop.ru_stime.tv_usec -
                           cpuStart.ru_stime.tv_usec) / 1000000.0;

    userSeconds = (double)(cpuStop.ru_utime.tv_sec -
                           cpuStart.ru_utime.tv_sec);
    userSeconds += (double)(cpuStop.ru_utime.tv_usec -
                            cpuStart.ru_utime.tv_usec) / 1000000.0;

    encodeTime = sysSeconds + userSeconds;

    view = [[[NSApp windows] objectAtIndex:0] contentView];

    siPrefix([view pixels] / realTime, "Pixels/s", s, sizeof(s));
    fprintf(stderr, "Fill rate: %s\n", s);
    fprintf(stderr, "Frame rate: %g fps\n", (double)[view frames] / realTime);
    fprintf(stderr, "CPU Usage: %g %%\n", 100.0 * encodeTime / realTime);

    return NSTerminateNow;
}

@end

int main ()
{
    [NSAutoreleasePool new];
    [NSApplication sharedApplication];
    [NSApp setActivationPolicy:NSApplicationActivationPolicyRegular];
    id menubar = [[NSMenu new] autorelease];
    id appMenuItem = [[NSMenuItem new] autorelease];
    [menubar addItem:appMenuItem];
    [NSApp setMainMenu:menubar];
    id appMenu = [[NSMenu new] autorelease];
    id appName = [[NSProcessInfo processInfo] processName];
    id quitTitle = [@"Quit " stringByAppendingString:appName];
    id quitMenuItem = [[[NSMenuItem alloc] initWithTitle:quitTitle
        action:@selector(terminate:) keyEquivalent:@"q"] autorelease];
    [appMenu addItem:quitMenuItem];
    [appMenuItem setSubmenu:appMenu];

    id window = [[[NSWindow alloc] initWithContentRect:NSMakeRect(0, 0, 1024, 768)
        styleMask:NSTitledWindowMask backing:NSBackingStoreBuffered defer:NO]
            autorelease];
    [window cascadeTopLeftFromPoint:NSMakePoint(20,20)];
    [window setTitle:appName];
    [window makeKeyAndOrderFront:nil];

    id view = [[MyView alloc] init];
    [window setContentView:view];

    [NSApp setDelegate:[[MyApp alloc] init]];

    [NSApp activateIgnoringOtherApps:YES];
    [NSApp run];

    return 0;
}