//
//  UIImageExtra.m
//  HedgewarsMobile
//
//  Created by Vittorio on 08/04/10.
//  Copyright 2010 __MyCompanyName__. All rights reserved.
//

#import "UIImageExtra.h"


@implementation UIImage (extra)

-(UIImage *)scaleToSize:(CGSize) size {
    DLog(@"warning - this is a very expensive operation, you should avoid using it");

    // Create a bitmap graphics context; this will also set it as the current context
    UIGraphicsBeginImageContext(size);

    // Draw the scaled image in the current context
    [self drawInRect:CGRectMake(0, 0, size.width, size.height)];

    // Create a new image from current context
    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();

    // Pop the current context from the stack
    UIGraphicsEndImageContext();

    // Return our new scaled image (autoreleased)
    return scaledImage;
}

-(UIImage *)mergeWith:(UIImage *)secondImage atPoint:(CGPoint) secondImagePoint {
    // create a contex of size of the background image
    return [self mergeWith:secondImage atPoint:secondImagePoint atSize:self.size];
}

-(UIImage *)mergeWith:(UIImage *)secondImage atPoint:(CGPoint) secondImagePoint atSize:(CGSize) resultingSize {
    if (secondImage == nil) {
        DLog(@"Warning, secondImage == nil");
        return self;
    }
    
    // Create a bitmap graphics context; this will also set it as the current context
    UIGraphicsBeginImageContext(resultingSize);

    // draw the background image in the current context
    [self drawAtPoint:CGPointMake(0,0)];

    // draw the image on top of the first image (because the context is the same)
    [secondImage drawAtPoint:secondImagePoint];

    // create an image from the current contex (not thread safe)
    UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();

    // free drawing contex
    UIGraphicsEndImageContext();

    // return the resulting autoreleased image
    return resultImage;
}

-(id) initWithContentsOfFile:(NSString *)path andCutAt:(CGRect) rect {
    // load image from path
    UIImage *image = [[UIImage alloc] initWithContentsOfFile: path];

    if (nil != image) {
        // get its CGImage representation with a give size
        CGImageRef cgImage = CGImageCreateWithImageInRect([image CGImage], rect);

        // clean memory
        [image release];

        // create a UIImage from the CGImage (memory must be allocated already)
        UIImage *sprite = [self initWithCGImage:cgImage];

        // clean memory
        CGImageRelease(cgImage);

        // return resulting image
        return sprite;
    } else {
        DLog(@"error - image == nil");
        return nil;
    }
}

-(UIImage *)cutAt:(CGRect) rect {
    CGImageRef cgImage = CGImageCreateWithImageInRect([self CGImage], rect);

    UIImage *res = [UIImage imageWithCGImage:cgImage];
    CGImageRelease(cgImage);

    return res;
}

-(UIImage *)convertToGrayScale {
    // Create image rectangle with current image width/height
    CGRect imageRect = CGRectMake(0, 0, self.size.width, self.size.height);

    // Grayscale color space
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();

    // Create bitmap content with current image size and grayscale colorspace
    CGContextRef context = CGBitmapContextCreate(nil, self.size.width, self.size.height, 8, 0, colorSpace, kCGImageAlphaNone);

    // Draw image into current context, with specified rectangle
    // using previously defined context (with grayscale colorspace)
    CGContextDrawImage(context, imageRect, [self CGImage]);

    // Create bitmap image info from pixel data in current context
    CGImageRef imageRef = CGBitmapContextCreateImage(context);

    // Create a new UIImage object
    UIImage *newImage = [UIImage imageWithCGImage:imageRef];

    // Release colorspace, context and bitmap information
    CGColorSpaceRelease(colorSpace);
    CGContextRelease(context);
    CFRelease(imageRef);

    // Return the new grayscale image
    return newImage;
}

// by http://iphonedevelopertips.com/cocoa/how-to-mask-an-image.html turned into a category by koda
-(UIImage*) maskImageWith:(UIImage *)maskImage {
    // prepare the reference image
    CGImageRef maskRef = [maskImage CGImage];

    // create the mask using parameters of the mask reference
    CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
                                        CGImageGetHeight(maskRef),
                                        CGImageGetBitsPerComponent(maskRef),
                                        CGImageGetBitsPerPixel(maskRef),
                                        CGImageGetBytesPerRow(maskRef),
                                        CGImageGetDataProvider(maskRef), NULL, false);

    // create an image in the current context
    CGImageRef masked = CGImageCreateWithMask([self CGImage], mask);
    CGImageRelease(mask);

    UIImage* retImage = [UIImage imageWithCGImage:masked];
    CGImageRelease(masked);

    return retImage;
}

// by http://blog.sallarp.com/iphone-uiimage-round-corners/ turned into a category by koda
void addRoundedRectToPath(CGContextRef context, CGRect rect, CGFloat ovalWidth, CGFloat ovalHeight) {
    CGFloat fw, fh;
    if (ovalWidth == 0 || ovalHeight == 0) {
        CGContextAddRect(context, rect);
        return;
    }
    CGContextSaveGState(context);
    CGContextTranslateCTM (context, CGRectGetMinX(rect), CGRectGetMinY(rect));
    CGContextScaleCTM (context, ovalWidth, ovalHeight);
    fw = CGRectGetWidth (rect) / ovalWidth;
    fh = CGRectGetHeight (rect) / ovalHeight;
    CGContextMoveToPoint(context, fw, fh/2);
    CGContextAddArcToPoint(context, fw, fh, fw/2, fh, 1);
    CGContextAddArcToPoint(context, 0, fh, 0, fh/2, 1);
    CGContextAddArcToPoint(context, 0, 0, fw/2, 0, 1);
    CGContextAddArcToPoint(context, fw, 0, fw, fh/2, 1);
    CGContextClosePath(context);
    CGContextRestoreGState(context);
}

-(UIImage *)makeRoundCornersOfSize:(CGSize) sizewh {
    CGFloat cornerWidth = sizewh.width;
    CGFloat cornerHeight = sizewh.height;
    CGFloat w = self.size.width;
    CGFloat h = self.size.height;

    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);

    CGContextBeginPath(context);
    CGRect rect = CGRectMake(0, 0, w, h);
    addRoundedRectToPath(context, rect, cornerWidth, cornerHeight);
    CGContextClosePath(context);
    CGContextClip(context);

    CGContextDrawImage(context, CGRectMake(0, 0, w, h), [self CGImage]);

    CGImageRef imageMasked = CGBitmapContextCreateImage(context);
    CGContextRelease(context);
    CGColorSpaceRelease(colorSpace);

    UIImage *newImage = [UIImage imageWithCGImage:imageMasked];
    CGImageRelease(imageMasked);

    return newImage;
}

@end