/*
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements. See the NOTICE file
distributed with this work for additional information
regarding copyright ownership. The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied. See the License for the
specific language governing permissions and limitations
under the License.
*/

#import "UIImage+CropScaleOrientation.h"

@implementation UIImage (CropScaleOrientation)

- (UIImage*)imageByScalingAndCroppingForSize:(CGSize)targetSize
{
UIImage* sourceImage = self;
UIImage* newImage = nil;
CGSize imageSize = sourceImage.size;
CGFloat width = imageSize.width;
CGFloat height = imageSize.height;
CGFloat targetWidth = targetSize.width;
CGFloat targetHeight = targetSize.height;
CGFloat scaleFactor = 0.0;
CGFloat scaledWidth = targetWidth;
CGFloat scaledHeight = targetHeight;
CGPoint thumbnailPoint = CGPointMake(0.0, 0.0);

if (CGSizeEqualToSize(imageSize, targetSize) == NO) {
CGFloat widthFactor = targetWidth / width;
CGFloat heightFactor = targetHeight / height;

if (widthFactor > heightFactor) {
scaleFactor = widthFactor; // scale to fit height
} else {
scaleFactor = heightFactor; // scale to fit width
}
scaledWidth = width * scaleFactor;
scaledHeight = height * scaleFactor;

// center the image
if (widthFactor > heightFactor) {
thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5;
} else if (widthFactor < heightFactor) {
thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
}
}

UIGraphicsBeginImageContext(targetSize); // this will crop

CGRect thumbnailRect = CGRectZero;
thumbnailRect.origin = thumbnailPoint;
thumbnailRect.size.width = scaledWidth;
thumbnailRect.size.height = scaledHeight;

[sourceImage drawInRect:thumbnailRect];

newImage = UIGraphicsGetImageFromCurrentImageContext();
if (newImage == nil) {
NSLog(@"could not scale image");
}

// pop the context to get back to the default
UIGraphicsEndImageContext();
return newImage;
}

- (UIImage*)imageCorrectedForCaptureOrientation:(UIImageOrientation)imageOrientation
{
float rotation_radians = 0;
bool perpendicular = false;

switch (imageOrientation) {
case UIImageOrientationUp :
rotation_radians = 0.0;
break;

case UIImageOrientationDown:
rotation_radians = M_PI; // don't be scared of radians, if you're reading this, you're good at math
break;

case UIImageOrientationRight:
rotation_radians = M_PI_2;
perpendicular = true;
break;

case UIImageOrientationLeft:
rotation_radians = -M_PI_2;
perpendicular = true;
break;

default:
break;
}

UIGraphicsBeginImageContext(CGSizeMake(self.size.width, self.size.height));
CGContextRef context = UIGraphicsGetCurrentContext();

// Rotate around the center point
CGContextTranslateCTM(context, self.size.width / 2, self.size.height / 2);
CGContextRotateCTM(context, rotation_radians);

CGContextScaleCTM(context, 1.0, -1.0);
float width = perpendicular ? self.size.height : self.size.width;
float height = perpendicular ? self.size.width : self.size.height;
CGContextDrawImage(context, CGRectMake(-width / 2, -height / 2, width, height), [self CGImage]);

// Move the origin back since the rotation might've change it (if its 90 degrees)
if (perpendicular) {
CGContextTranslateCTM(context, -self.size.height / 2, -self.size.width / 2);
}

UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}

- (UIImage*)imageCorrectedForCaptureOrientation
{
return [self imageCorrectedForCaptureOrientation:[self imageOrientation]];
}

- (UIImage*)imageByScalingNotCroppingForSize:(CGSize)targetSize
{
UIImage* sourceImage = self;
UIImage* newImage = nil;
CGSize imageSize = sourceImage.size;
CGFloat width = imageSize.width;
CGFloat height = imageSize.height;
CGFloat targetWidth = targetSize.width;
CGFloat targetHeight = targetSize.height;
CGFloat scaleFactor = 0.0;
CGSize scaledSize = targetSize;

if (CGSizeEqualToSize(imageSize, targetSize) == NO) {
CGFloat widthFactor = targetWidth / width;
CGFloat heightFactor = targetHeight / height;

// opposite comparison to imageByScalingAndCroppingForSize in order to contain the image within the given bounds
if (widthFactor > heightFactor) {
scaleFactor = heightFactor; // scale to fit height
} else {
scaleFactor = widthFactor; // scale to fit width
}
scaledSize = CGSizeMake(MIN(width * scaleFactor, targetWidth), MIN(height * scaleFactor, targetHeight));
}

// If the pixels are floats, it causes a white line in iOS8 and probably other versions too
scaledSize.width = (int)scaledSize.width;
scaledSize.height = (int)scaledSize.height;

UIGraphicsBeginImageContext(scaledSize); // this will resize

[sourceImage drawInRect:CGRectMake(0, 0, scaledSize.width, scaledSize.height)];

newImage = UIGraphicsGetImageFromCurrentImageContext();
if (newImage == nil) {
NSLog(@"could not scale image");
}

// pop the context to get back to the default
UIGraphicsEndImageContext();
return newImage;
}

@end