From cf17a504ac8fb4a8f09b88e77dc1dfee5f30c348 Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Sun, 11 Aug 2013 09:54:49 -0700
Subject: [PATCH 01/14] remove redundant `CGImageSoureCopyPropertiesAtIndex`

---
 OGImage/__OGImage.m | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/OGImage/__OGImage.m b/OGImage/__OGImage.m
index 54e460f..08451db 100644
--- a/OGImage/__OGImage.m
+++ b/OGImage/__OGImage.m
@@ -89,8 +89,7 @@ - (id)initWithData:(NSData *)data scale:(CGFloat)scale {
             // do we have an OGImageDictionary?
             _originalFileType = (__bridge NSString *)CGImageSourceGetType(imageSource);
             _originalFileAlphaInfo = CGImageGetAlphaInfo(cgImage);
-            NSDictionary *propDict = CFBridgingRelease(CGImageSourceCopyPropertiesAtIndex(imageSource, 0, NULL));
-            _originalFileOrientation = [propDict[(__bridge NSString *)kCGImagePropertyOrientation] integerValue];
+            _originalFileOrientation = [_originalFileProperties[(__bridge NSString *)kCGImagePropertyOrientation] integerValue];
             self = [super initWithCGImage:cgImage scale:scale orientation:OGEXIFOrientationToUIImageOrientation(_originalFileOrientation)];
             CGImageRelease(cgImage);
         }

From 953fbfc42366b7b2706d71c216213c07293288a3 Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Fri, 23 Aug 2013 14:26:31 -0700
Subject: [PATCH 02/14] adds scaling method to key.

This fixes a subtle bug where if you scaled an image using one scale method, then requested the same image at the same size but with a different scale method, you'd get a hit from the cache for the earlier image (i.e., the wrong scale method)
---
 OGImage/OGScaledImage.m | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/OGImage/OGScaledImage.m b/OGImage/OGScaledImage.m
index 9424332..f7d9855 100644
--- a/OGImage/OGScaledImage.m
+++ b/OGImage/OGScaledImage.m
@@ -8,8 +8,8 @@
 #import "OGScaledImage.h"
 #import "OGImageCache.h"
 
-NSString *OGKeyWithSize(NSString *origKey, CGSize size, CGFloat cornerRadius) {
-    return [NSString stringWithFormat:@"%@-%f-%f-%f", origKey, size.width, size.height, cornerRadius];
+NSString *OGKeyWithSize(NSString *origKey, CGSize size, CGFloat cornerRadius, OGImageProcessingScaleMethod method) {
+    return [NSString stringWithFormat:@"%@-%f-%f-%f-%d", origKey, size.width, size.height, cornerRadius, method];
 }
 
 @implementation OGScaledImage {
@@ -45,7 +45,7 @@ - (id)initWithURL:(NSURL *)url size:(CGSize)size cornerRadius:(CGFloat)cornerRad
         self.scaledImage = placeholderImage;
         _scaledSize = size;
         _cornerRadius = cornerRadius;
-        _scaledKey = OGKeyWithSize(self.key, _scaledSize, _cornerRadius);
+        _scaledKey = OGKeyWithSize(self.key, _scaledSize, _cornerRadius, method);
         [self loadImageFromURL];
     }
     return self;

From c0af5934e6caa9bed8d6bec88ed388cb7f4b13c1 Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Fri, 23 Aug 2013 14:44:51 -0700
Subject: [PATCH 03/14] adds `OGImageView`

`OGImageView` is a subclass of `UIImageView` that encapsulates all the behavior of `OGImage` (specifically, `OGScaledImage`) to handle the most common case of loading an image from a URL
and displaying it.
---
 OGImage/OGImageView.h | 32 ++++++++++++++++++++++++++
 OGImage/OGImageView.m | 52 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 84 insertions(+)
 create mode 100644 OGImage/OGImageView.h
 create mode 100644 OGImage/OGImageView.m

diff --git a/OGImage/OGImageView.h b/OGImage/OGImageView.h
new file mode 100644
index 0000000..e3d8b86
--- /dev/null
+++ b/OGImage/OGImageView.h
@@ -0,0 +1,32 @@
+//
+//  OGImageView.h
+//  OGImageDemo
+//
+//  Created by Art Gillespie on 8/23/13.
+//  Copyright (c) 2013 Origami Labs. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+@interface OGImageView : UIImageView
+
+/**
+ * Set image view's image with the image at `url`. `OGImageView` supports the following
+ * protocols:
+ *
+ * * `http` 
+ * * `file`
+ * * `assets-library`
+ *
+ * The image will be scaled and fit according to the view's `bounds` and `contentMode`,
+ * respectively.
+ */
+- (void)setImageURL:(NSURL *)url placeholder:(UIImage *)image;
+
+/**
+ * If there's a problem loading the image, this property will be set. KVO-observable.
+ * @see `OGImage.error`
+ */
+@property (nonatomic, strong, readonly) NSError *imageError;
+
+@end
diff --git a/OGImage/OGImageView.m b/OGImage/OGImageView.m
new file mode 100644
index 0000000..e0a170c
--- /dev/null
+++ b/OGImage/OGImageView.m
@@ -0,0 +1,52 @@
+//
+//  OGImageView.m
+//  OGImageDemo
+//
+//  Created by Art Gillespie on 8/23/13.
+//  Copyright (c) 2013 Origami Labs. All rights reserved.
+//
+
+#import "OGImageView.h"
+#import "OGScaledImage.h"
+
+static NSString *KVOContext = @"OGImageView observation";
+
+@implementation OGImageView {
+    OGScaledImage *_scaledImage;
+}
+
+- (void)setImageURL:(NSURL *)url placeholder:(UIImage *)placeholder {
+    self.image = placeholder;
+    [_scaledImage removeObserver:self context:&KVOContext];
+    OGImageProcessingScaleMethod scaleMethod = OGImageProcessingScale_AspectFill;
+    if (UIViewContentModeScaleAspectFit == self.contentMode) {
+        scaleMethod = OGImageProcessingScale_AspectFit;
+    }
+    _scaledImage = [[OGScaledImage alloc] initWithURL:url size:self.bounds.size cornerRadius:0.f method:scaleMethod key:nil placeholderImage:nil];
+    [_scaledImage addObserver:self context:&KVOContext];
+    if (nil != _scaledImage.scaledImage) {
+        self.image = _scaledImage.scaledImage;
+    }
+}
+
+#pragma mark KVO
+
+- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
+    if (((void *)&KVOContext) == context) {
+        if ([@"scaledImage" isEqualToString:keyPath]) {
+            self.image = _scaledImage.scaledImage;
+        } else if ([@"error" isEqualToString:keyPath]) {
+            [self willChangeValueForKey:@"imageError"];
+            _imageError = _scaledImage.error;
+            [self didChangeValueForKey:@"imageError"];
+        }
+    } else {
+        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
+    }
+}
+
+- (void)dealloc {
+    [_scaledImage removeObserver:self context:&KVOContext];
+}
+
+@end

From 800daf53eb1e1195e8fcf8f74e3dd7432276fc0c Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Fri, 23 Aug 2013 14:45:23 -0700
Subject: [PATCH 04/14] updates demo for `OGImageView` and iOS 7.

---
 .../OGImageDemo.xcodeproj/project.pbxproj     | 14 +++--
 OGImageDemo/OGImageDemo/OGAppDelegate.m       |  3 +-
 .../OGImageDemo/OGImageTableViewCell.h        |  5 +-
 .../OGImageDemo/OGImageTableViewCell.m        | 53 +++++--------------
 OGImageDemo/OGImageDemo/OGViewController.m    | 10 ++--
 5 files changed, 31 insertions(+), 54 deletions(-)

diff --git a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
index 5856587..eba7c17 100644
--- a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
+++ b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
@@ -57,6 +57,7 @@
 		C88272321663DBDF007D409F /* OGViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = C88272311663DBDF007D409F /* OGViewController.m */; };
 		C88272351663DBDF007D409F /* OGViewController.xib in Resources */ = {isa = PBXBuildFile; fileRef = C88272331663DBDF007D409F /* OGViewController.xib */; };
 		C882723E1663E5B0007D409F /* OGImage.m in Sources */ = {isa = PBXBuildFile; fileRef = C882723D1663E5B0007D409F /* OGImage.m */; };
+		C88AE28F17C7EDD4002A34C7 /* OGImageView.m in Sources */ = {isa = PBXBuildFile; fileRef = C88AE28E17C7EDD4002A34C7 /* OGImageView.m */; };
 		C8975AEA166E09BB00C2D53A /* OGScaledImage.m in Sources */ = {isa = PBXBuildFile; fileRef = C8975AE9166E09BB00C2D53A /* OGScaledImage.m */; };
 		C8975AEB166E09BB00C2D53A /* OGScaledImage.m in Sources */ = {isa = PBXBuildFile; fileRef = C8975AE9166E09BB00C2D53A /* OGScaledImage.m */; };
 		C8FADED9166D5DB100829179 /* Accelerate.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C8FADED8166D5DB100829179 /* Accelerate.framework */; };
@@ -119,6 +120,8 @@
 		C88272341663DBDF007D409F /* en */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = en; path = en.lproj/OGViewController.xib; sourceTree = "<group>"; };
 		C882723C1663E5B0007D409F /* OGImage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGImage.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
 		C882723D1663E5B0007D409F /* OGImage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImage.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
+		C88AE28D17C7EDD4002A34C7 /* OGImageView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OGImageView.h; sourceTree = "<group>"; };
+		C88AE28E17C7EDD4002A34C7 /* OGImageView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OGImageView.m; sourceTree = "<group>"; };
 		C8975AE8166E09BB00C2D53A /* OGScaledImage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGScaledImage.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
 		C8975AE9166E09BB00C2D53A /* OGScaledImage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGScaledImage.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		C8FADED8166D5DB100829179 /* Accelerate.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Accelerate.framework; path = System/Library/Frameworks/Accelerate.framework; sourceTree = SDKROOT; };
@@ -272,6 +275,8 @@
 		C882723B1663E570007D409F /* OGImage */ = {
 			isa = PBXGroup;
 			children = (
+				C83BE57C16C5904600D82A1A /* __OGImage.h */,
+				C83BE57D16C5904600D82A1A /* __OGImage.m */,
 				C80306321665421300073395 /* OGCachedImage.h */,
 				C80306331665421300073395 /* OGCachedImage.m */,
 				C882723C1663E5B0007D409F /* OGImage.h */,
@@ -282,12 +287,12 @@
 				C8711464166417DE0015A743 /* OGImageLoader.m */,
 				C86E0BEA1667FE36006063B6 /* OGImageProcessing.h */,
 				C86E0BEB1667FE36006063B6 /* OGImageProcessing.m */,
-				C8975AE8166E09BB00C2D53A /* OGScaledImage.h */,
-				C8975AE9166E09BB00C2D53A /* OGScaledImage.m */,
 				C808967A1694DFC0009BE21D /* OGImageRequest.h */,
 				C808967B1694DFC0009BE21D /* OGImageRequest.m */,
-				C83BE57C16C5904600D82A1A /* __OGImage.h */,
-				C83BE57D16C5904600D82A1A /* __OGImage.m */,
+				C88AE28D17C7EDD4002A34C7 /* OGImageView.h */,
+				C88AE28E17C7EDD4002A34C7 /* OGImageView.m */,
+				C8975AE8166E09BB00C2D53A /* OGScaledImage.h */,
+				C8975AE9166E09BB00C2D53A /* OGScaledImage.m */,
 			);
 			name = OGImage;
 			path = ../../OGImage;
@@ -445,6 +450,7 @@
 				C8975AEA166E09BB00C2D53A /* OGScaledImage.m in Sources */,
 				C808967C1694DFC0009BE21D /* OGImageRequest.m in Sources */,
 				C83BE57E16C5904600D82A1A /* __OGImage.m in Sources */,
+				C88AE28F17C7EDD4002A34C7 /* OGImageView.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
diff --git a/OGImageDemo/OGImageDemo/OGAppDelegate.m b/OGImageDemo/OGImageDemo/OGAppDelegate.m
index 54781eb..0b9ca10 100644
--- a/OGImageDemo/OGImageDemo/OGAppDelegate.m
+++ b/OGImageDemo/OGImageDemo/OGAppDelegate.m
@@ -17,7 +17,8 @@ - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(
     self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
     // Override point for customization after application launch.
     self.viewController = [[OGViewController alloc] initWithNibName:@"OGViewController" bundle:nil];
-    self.window.rootViewController = self.viewController;
+    UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:self.viewController];
+    self.window.rootViewController = navController;
     [self.window makeKeyAndVisible];
     [self setupLogging];
     return YES;
diff --git a/OGImageDemo/OGImageDemo/OGImageTableViewCell.h b/OGImageDemo/OGImageDemo/OGImageTableViewCell.h
index b6fd3ae..1a4c3bc 100644
--- a/OGImageDemo/OGImageDemo/OGImageTableViewCell.h
+++ b/OGImageDemo/OGImageDemo/OGImageTableViewCell.h
@@ -7,11 +7,10 @@
 //
 
 #import <UIKit/UIKit.h>
-
-@class OGScaledImage;
+#import "OGImageView.h"
 
 @interface OGImageTableViewCell : UITableViewCell
 
-@property (nonatomic, strong) OGScaledImage *image;
+@property (nonatomic, readonly, strong) OGImageView *ogImageView;
 
 @end
diff --git a/OGImageDemo/OGImageDemo/OGImageTableViewCell.m b/OGImageDemo/OGImageDemo/OGImageTableViewCell.m
index 371c701..f9096e2 100644
--- a/OGImageDemo/OGImageDemo/OGImageTableViewCell.m
+++ b/OGImageDemo/OGImageDemo/OGImageTableViewCell.m
@@ -7,15 +7,17 @@
 //
 
 #import "OGImageTableViewCell.h"
-#import "OGScaledImage.h"
-
-static NSString *KVOContext = @"OGImageTableViewCell observation";
 
 @implementation OGImageTableViewCell
 
 - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier {
     self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
     if (self) {
+        OGImageView *tmp = [[OGImageView alloc] initWithFrame:CGRectMake(0.f, 0.f, self.bounds.size.height, self.bounds.size.height)];
+        tmp.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
+        [self.contentView addSubview:tmp];
+        _ogImageView = tmp;
+        _ogImageView.clipsToBounds = YES;
     }
     return self;
 }
@@ -24,44 +26,15 @@ - (void)setSelected:(BOOL)selected animated:(BOOL)animated {
     [super setSelected:selected animated:animated];
 }
 
-#pragma mark - KVO
-
-- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
-    if( (void *)&KVOContext == context ) {
-        NSAssert(YES == [NSThread isMainThread], @"KVO fired on thread other than main...");
-        if ([keyPath isEqualToString:@"scaledImage"]) {
-            self.imageView.image = self.image.scaledImage;
-            self.textLabel.text = [[self.image.url path] lastPathComponent];
-            self.detailTextLabel.text = [NSString stringWithFormat:@"%.2f", self.image.loadTime];
-        } else if ([keyPath isEqualToString:@"error"]) {
-            
-        }
+- (void)layoutSubviews {
+    [super layoutSubviews];
+    // move the textLabel over to accomodate the ogImageView
+    CGRect f = self.textLabel.frame;
+    f.origin.x = self.ogImageView.bounds.size.width + 5.f;
+    if (self.bounds.size.width - 10.f < f.origin.x + f.size.width) {
+        f.size.width = self.bounds.size.width - 10.f - f.origin.x;
     }
-    else {
-        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
-    }
-}
-
-#pragma mark - Properties
-
-- (void)setImage:(OGScaledImage *)image {
-    /*
-     * When the cell's image is set, we want to first make sure we're no longer listening
-     * for any KVO notifications on the cell's previous image.
-     */
-    [_image removeObserver:self forKeyPath:@"error" context:&KVOContext];
-    [_image removeObserver:self forKeyPath:@"scaledImage" context:&KVOContext];
-    _image = image;
-    self.imageView.image = _image.scaledImage;
-    self.textLabel.text = [[self.image.url path] lastPathComponent];
-    self.detailTextLabel.text = NSLocalizedString(@"Loading", @"");
-    [_image addObserver:self forKeyPath:@"error" options:NSKeyValueObservingOptionNew context:&KVOContext];
-    [_image addObserver:self forKeyPath:@"scaledImage" options:NSKeyValueObservingOptionNew context:&KVOContext];
-}
-
-- (void)dealloc {
-    [_image removeObserver:self forKeyPath:@"error" context:&KVOContext];
-    [_image removeObserver:self forKeyPath:@"scaledImage" context:&KVOContext];
+    self.textLabel.frame = f;
 }
 
 @end
diff --git a/OGImageDemo/OGImageDemo/OGViewController.m b/OGImageDemo/OGImageDemo/OGViewController.m
index 6e97816..b760ec3 100644
--- a/OGImageDemo/OGImageDemo/OGViewController.m
+++ b/OGImageDemo/OGImageDemo/OGViewController.m
@@ -7,7 +7,6 @@
 //
 
 #import "OGViewController.h"
-#import "OGScaledImage.h"
 #import "OGImageTableViewCell.h"
 
 @interface OGViewController ()
@@ -20,13 +19,12 @@ @implementation OGViewController {
 
 - (void)viewDidLoad {
     [super viewDidLoad];
+    self.title = NSLocalizedString(@"OGImageDemo", @"");
     [self loadJSON];
-	// Do any additional setup after loading the view, typically from a nib.
 }
 
 - (void)didReceiveMemoryWarning {
     [super didReceiveMemoryWarning];
-    // Dispose of any resources that can be recreated.
 }
 
 - (void)loadJSON {
@@ -62,11 +60,11 @@ - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(N
     OGImageTableViewCell *cell = (OGImageTableViewCell *)[self.tableView dequeueReusableCellWithIdentifier:OGImageCellIdentifier];
     if (nil == cell) {
         cell = [[OGImageTableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:OGImageCellIdentifier];
+        cell.ogImageView.contentMode = UIViewContentModeScaleAspectFill;
     }
     NSURL *imageURL = [NSURL URLWithString:_urls[indexPath.row]];
-    CGFloat imageSide = self.tableView.rowHeight;
-    OGScaledImage *image = [[OGScaledImage alloc] initWithURL:imageURL size:CGSizeMake(imageSide, imageSide) cornerRadius:0.f method:OGImageProcessingScale_AspectFill key:nil placeholderImage:[UIImage imageNamed:@"placeholder"]];
-    cell.image = image;
+    [cell.ogImageView setImageURL:imageURL placeholder:[UIImage imageNamed:@"placeholder"]];
+    cell.textLabel.text = [imageURL lastPathComponent];
     return cell;
 }
 

From 0edf217f0843dd38e208307d5dd37a80903380bf Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Fri, 23 Aug 2013 15:02:19 -0700
Subject: [PATCH 05/14] Updates readme with description of `OGImageView`

---
 README.md | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 106c954..c53da14 100644
--- a/README.md
+++ b/README.md
@@ -13,9 +13,28 @@ more information.
 The idea behind `OGImage` is to encapsulate best practices for loading images
 over HTTP in a simple, extensible interface.
 
+### OGImageView
+
+If all you need is to load an image and display it in a `UIImageView`, check out
+`OGImageView`, a `UIImageView` subclass that adds a single method:
+
+```objc
+
+   [cell.ogImageView setImageURL:someURL placeholder:[UIImage imageNamed:@"placeholder"]];
+
+```
+
+This one call will handle fetching the image at `someURL` (regardless of whether it's a network, file
+or even `assets-library:` url), scaling it to the `OGImageView`s `bounds.size` obeying `contentMode` *and*
+caching it in memory and on-disk, and swapping out your placeholder image with the new image.
+
+Furthermore, if `setImageURL:placeholder:` is called on an existing `OGImageView` instance (e.g., when
+its containing `UITableViewCell` is recycled) `OGImageView` will behave as you'd expect: It loses interest
+in the previously requested URL and the current URL is given first priority for fetching/processing.
+
 ### Philosophy
 
-* The default use case should be *ridiculously* simple to execute. In OGImage,
+* The default use case should be *ridiculously* simple to execute (see `[OGImageView]`(#OGImageView)). In OGImage,
   you can load, cache, and scale an image with the following call:
 
     ```objc

From 1b6f62c817db40ec7b06afee452a4fd060eda533 Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Fri, 23 Aug 2013 15:05:32 -0700
Subject: [PATCH 06/14] readme link formatting

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index c53da14..f64c475 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ in the previously requested URL and the current URL is given first priority for
 
 ### Philosophy
 
-* The default use case should be *ridiculously* simple to execute (see `[OGImageView]`(#OGImageView)). In OGImage,
+* The default use case should be *ridiculously* simple to execute (see `[OGImageView](#OGImageView)`). In OGImage,
   you can load, cache, and scale an image with the following call:
 
     ```objc

From a82cbcfece28f7505c2d55187eded8e35147490a Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Fri, 23 Aug 2013 15:06:47 -0700
Subject: [PATCH 07/14] adds mo' readme fixes.

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index f64c475..ac22e72 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ in the previously requested URL and the current URL is given first priority for
 
 ### Philosophy
 
-* The default use case should be *ridiculously* simple to execute (see `[OGImageView](#OGImageView)`). In OGImage,
+* The default use case should be *ridiculously* simple to execute (see <code>[OGImageView](#OGImageView)</code>). In OGImage,
   you can load, cache, and scale an image with the following call:
 
     ```objc

From 193aba98f7f0f61d44922b0c066a38da6e523581 Mon Sep 17 00:00:00 2001
From: Art Gillespie <art@tapsquare.com>
Date: Tue, 27 Aug 2013 09:10:13 -0700
Subject: [PATCH 08/14] Minor formatting in README.md

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index ac22e72..e00f28e 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ If all you need is to load an image and display it in a `UIImageView`, check out
 
 ```objc
 
-   [cell.ogImageView setImageURL:someURL placeholder:[UIImage imageNamed:@"placeholder"]];
+[cell.ogImageView setImageURL:someURL placeholder:[UIImage imageNamed:@"placeholder"]];
 
 ```
 

From ec8286738f82522fef3b3496588dc52a2108d57a Mon Sep 17 00:00:00 2001
From: Sixten Otto <opensource@sfko.com>
Date: Fri, 14 Mar 2014 15:54:01 -0700
Subject: [PATCH 09/14] test coverage for some issues that have cropped up in
 our apps

---
 .../OGImageDemo.xcodeproj/project.pbxproj     |  12 +-
 .../OGImageProblematicProcessingTests.m       | 123 ++++++++++++++++++
 OGImageDemo/OGImageTests/moldex-logo.gif      | Bin 0 -> 2101 bytes
 3 files changed, 133 insertions(+), 2 deletions(-)
 create mode 100644 OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
 create mode 100644 OGImageDemo/OGImageTests/moldex-logo.gif

diff --git a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
index eba7c17..c8d8cf7 100644
--- a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
+++ b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
@@ -8,6 +8,8 @@
 
 /* Begin PBXBuildFile section */
 		416DC6759A8046D6AED27FFE /* libPods.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 467479B3192A45B8984313B7 /* libPods.a */; };
+		9C46672118D39709008960BA /* moldex-logo.gif in Resources */ = {isa = PBXBuildFile; fileRef = 9C46672018D39709008960BA /* moldex-logo.gif */; };
+		9C46672318D39EA7008960BA /* OGImageProblematicProcessingTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 9C46672218D39EA7008960BA /* OGImageProblematicProcessingTests.m */; };
 		C803062A166526A900073395 /* james_bond.json in Resources */ = {isa = PBXBuildFile; fileRef = C8030629166526A900073395 /* james_bond.json */; };
 		C803062D1665295A00073395 /* OGImageTableViewCell.m in Sources */ = {isa = PBXBuildFile; fileRef = C803062C1665295A00073395 /* OGImageTableViewCell.m */; };
 		C803063016652E8200073395 /* placeholder.png in Resources */ = {isa = PBXBuildFile; fileRef = C803062E16652E8200073395 /* placeholder.png */; };
@@ -66,6 +68,8 @@
 
 /* Begin PBXFileReference section */
 		467479B3192A45B8984313B7 /* libPods.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libPods.a; sourceTree = BUILT_PRODUCTS_DIR; };
+		9C46672018D39709008960BA /* moldex-logo.gif */ = {isa = PBXFileReference; lastKnownFileType = image.gif; path = "moldex-logo.gif"; sourceTree = "<group>"; };
+		9C46672218D39EA7008960BA /* OGImageProblematicProcessingTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OGImageProblematicProcessingTests.m; sourceTree = "<group>"; };
 		9F932054786D4C9BA76B5EBE /* Pods.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = Pods.xcconfig; path = Pods/Pods.xcconfig; sourceTree = SOURCE_ROOT; };
 		C8030629166526A900073395 /* james_bond.json */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.json; name = james_bond.json; path = "Demo Data/james_bond.json"; sourceTree = "<group>"; };
 		C803062B1665295A00073395 /* OGImageTableViewCell.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGImageTableViewCell.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
@@ -86,9 +90,9 @@
 		C83BE57C16C5904600D82A1A /* __OGImage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = __OGImage.h; sourceTree = "<group>"; };
 		C83BE57D16C5904600D82A1A /* __OGImage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = __OGImage.m; sourceTree = "<group>"; };
 		C84972AF166564D000DB15D1 /* OGImageCache.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGImageCache.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
-		C84972B0166564D000DB15D1 /* OGImageCache.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImageCache.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
+		C84972B0166564D000DB15D1 /* OGImageCache.m */ = {isa = PBXFileReference; fileEncoding = 4; indentWidth = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImageCache.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		C86E0BEA1667FE36006063B6 /* OGImageProcessing.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGImageProcessing.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
-		C86E0BEB1667FE36006063B6 /* OGImageProcessing.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImageProcessing.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
+		C86E0BEB1667FE36006063B6 /* OGImageProcessing.m */ = {isa = PBXFileReference; fileEncoding = 4; indentWidth = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImageProcessing.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		C86E0BF01667FF9E006063B6 /* OGImageProcessingTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImageProcessingTests.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		C871143F16640E510015A743 /* OGImageTests.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = OGImageTests.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		C871144616640E510015A743 /* OGImageTests-Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = "OGImageTests-Info.plist"; sourceTree = "<group>"; };
@@ -173,6 +177,7 @@
 			isa = PBXGroup;
 			children = (
 				C8392EAC169CA1E100F0907A /* Origami.jpg */,
+				9C46672018D39709008960BA /* moldex-logo.gif */,
 			);
 			name = Resources;
 			sourceTree = "<group>";
@@ -187,6 +192,7 @@
 				C8392EAF169CA21700F0907A /* OGImageFileTests.m */,
 				C87C645E16C46C70006217C9 /* OGImageIdempotentTests.m */,
 				C86E0BF01667FF9E006063B6 /* OGImageProcessingTests.m */,
+				9C46672218D39EA7008960BA /* OGImageProblematicProcessingTests.m */,
 				C808967F1694ED01009BE21D /* OGImageTestsAppDelegate.h */,
 				C80896801694ED01009BE21D /* OGImageTestsAppDelegate.m */,
 			);
@@ -371,6 +377,7 @@
 			files = (
 				C871144916640E510015A743 /* InfoPlist.strings in Resources */,
 				C871145116640E510015A743 /* Default.png in Resources */,
+				9C46672118D39709008960BA /* moldex-logo.gif in Resources */,
 				C871145316640E510015A743 /* Default@2x.png in Resources */,
 				C871145516640E510015A743 /* Default-568h@2x.png in Resources */,
 				C8392EAD169CA1E100F0907A /* Origami.jpg in Resources */,
@@ -417,6 +424,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				C871144B16640E510015A743 /* main.m in Sources */,
+				9C46672318D39EA7008960BA /* OGImageProblematicProcessingTests.m in Sources */,
 				C871146116640F7D0015A743 /* OGImageAsyncTests.m in Sources */,
 				C8711462166410CD0015A743 /* OGImage.m in Sources */,
 				C8711466166417E20015A743 /* OGImageLoader.m in Sources */,
diff --git a/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m b/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
new file mode 100644
index 0000000..0b2b0da
--- /dev/null
+++ b/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
@@ -0,0 +1,123 @@
+//
+//  OGImageProblematicProcessingTests.m
+//  OGImageDemo
+//
+//  Created by Sixten Otto on 3/14/14.
+//  Copyright (c) 2014 Sixten Otto. All rights reserved.
+//
+
+#import <Accelerate/Accelerate.h>
+#import <GHUnitIOS/GHUnit.h>
+#import "OGImageProcessing.h"
+#import "OGScaledImage.h"
+#import "OGImageCache.h"
+
+extern OSStatus UIImageToVImageBuffer(UIImage *image, vImage_Buffer *buffer, CGImageAlphaInfo alphaInfo);
+
+static NSString *KVOContext = @"OGImageProblematicProcessingTests observation";
+static const CGSize TEST_SCALE_SIZE = {100.f, 20.f};
+
+@interface NoOpAssertionHandler : NSAssertionHandler
+@end
+
+
+@interface OGImageProblematicProcessingTests : GHAsyncTestCase
+@end
+
+@implementation OGImageProblematicProcessingTests
+
+- (void)setUp {
+    // make sure we get the image from the network
+    [[OGImageCache shared] purgeCache:YES];
+}
+
+- (void)tearDown {
+    // clean up the in-memory and disk cache when we're done
+    [[OGImageCache shared] purgeCache:YES];
+}
+
+- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
+  if( (void *)&KVOContext == context ) {
+    NSAssert(YES == [NSThread isMainThread], @"Expected `observeValueForKeyPath` to only be called on main thread");
+    if( [keyPath isEqualToString:@"scaledImage"] ) {
+      OGScaledImage *image = (OGScaledImage *)object;
+      GHTestLog(@"Scaled image loaded: %@ : %@", image.image, NSStringFromCGSize(image.scaledImage.size));
+      if( nil == image ) {
+        [self notify:kGHUnitWaitStatusFailure];
+      }
+      else {
+        [self notify:kGHUnitWaitStatusSuccess];
+      }
+      return;
+    }
+  }
+  else {
+    [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
+  }
+}
+
+- (void)testScalingGif
+{
+  [self prepare];
+  NSURL *url = [[NSBundle mainBundle] URLForResource:@"moldex-logo" withExtension:@"gif"];
+  OGScaledImage *image = [[OGScaledImage alloc] initWithURL:url size:TEST_SCALE_SIZE key:nil];
+  [image addObserver:self context:&KVOContext];
+  [self waitForStatus:kGHUnitWaitStatusSuccess timeout:10.];
+  [image removeObserver:self context:&KVOContext];
+}
+
+- (void)testCachingNil
+{
+  NSURL *url = [[NSBundle mainBundle] URLForResource:@"moldex-logo" withExtension:@"gif"];
+  __OGImage *image = [[__OGImage alloc] initWithDataAtURL:url];
+  GHAssertNotNil(image, @"Couldn't decode test image");
+  
+  // make sure that the test isn't interrupted by assert failure
+  NSAssertionHandler *oldHandler = [[[NSThread currentThread] threadDictionary] valueForKey:NSAssertionHandlerKey];
+  NSAssertionHandler *tempHandler = [NoOpAssertionHandler new];
+  [[[NSThread currentThread] threadDictionary] setValue:tempHandler forKey:NSAssertionHandlerKey];
+  
+  GHAssertNoThrowSpecific([[OGImageCache shared] setImage:nil forKey:@"foo"], NSException, NSInvalidArgumentException, @"Attempting to insert a nil image should not throw");
+  GHAssertNoThrowSpecific([[OGImageCache shared] setImage:image forKey:nil], NSException, NSInvalidArgumentException, @"Attempting to insert with a nil key should not throw");
+  
+  [[[NSThread currentThread] threadDictionary] setValue:oldHandler forKey:NSAssertionHandlerKey];
+}
+
+- (void)testConvertingBadAlpha_Last
+{
+  NSString *path = [[NSBundle mainBundle] pathForResource:@"moldex-logo" ofType:@"gif"];
+  UIImage *image = [[UIImage alloc] initWithContentsOfFile:path];
+  
+  vImage_Buffer vBuffer;
+  OSStatus result = UIImageToVImageBuffer(image, &vBuffer, kCGImageAlphaLast);
+  GHAssertErr(OGImageProcessingError, result, @"Operation should report failure");
+  GHAssertNULL(vBuffer.data, @"Buffer should have NULL data pointer");
+}
+
+- (void)testConvertingBadAlpha_First
+{
+  NSString *path = [[NSBundle mainBundle] pathForResource:@"moldex-logo" ofType:@"gif"];
+  UIImage *image = [[UIImage alloc] initWithContentsOfFile:path];
+  
+  vImage_Buffer vBuffer;
+  OSStatus result = UIImageToVImageBuffer(image, &vBuffer, kCGImageAlphaFirst);
+  GHAssertErr(OGImageProcessingError, result, @"Operation should report failure");
+  GHAssertNULL(vBuffer.data, @"Buffer should have NULL data pointer");
+}
+
+@end
+
+@implementation NoOpAssertionHandler
+
+- (void)handleFailureInMethod:(SEL)selector object:(id)object file:(NSString *)fileName lineNumber:(NSInteger)line description:(NSString *)format, ...
+{
+  NSLog(@"Assertion failure (ignored): %@ for object %@ in %@#%i", NSStringFromSelector(selector), object, fileName, line);
+}
+
+- (void)handleFailureInFunction:(NSString *)functionName file:(NSString *)fileName lineNumber:(NSInteger)line description:(NSString *)format, ...
+{
+  NSLog(@"Assertion failure (ignored): %@ in %@#%i", functionName, fileName, line);
+}
+
+@end
+
diff --git a/OGImageDemo/OGImageTests/moldex-logo.gif b/OGImageDemo/OGImageTests/moldex-logo.gif
new file mode 100644
index 0000000000000000000000000000000000000000..ed96162bb918f18c8a3506e0542024c6f34b3802
GIT binary patch
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From e8d2a36e1f19d71f20f76e18456aa30c39313c05 Mon Sep 17 00:00:00 2001
From: Sixten Otto <opensource@sfko.com>
Date: Fri, 14 Mar 2014 15:55:03 -0700
Subject: [PATCH 10/14] when someone tries to cache an empty image/key, don't
 crash in production

---
 OGImage/OGImageCache.m | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/OGImage/OGImageCache.m b/OGImage/OGImageCache.m
index 781935d..bc33a21 100644
--- a/OGImage/OGImageCache.m
+++ b/OGImage/OGImageCache.m
@@ -104,8 +104,13 @@ - (void)imageForKey:(NSString *)key block:(OGImageCacheCompletionBlock)block {
 }
 
 - (void)setImage:(__OGImage *)image forKey:(NSString *)key {
+    // assert for developers, and guard against production crashes
     NSParameterAssert(nil != image);
     NSParameterAssert(nil != key);
+    if (nil == image || nil == key) {
+        return;
+    }
+    
     [_memoryCache setObject:image forKey:key];
     dispatch_async(_cacheFileTasksQueue, ^{
         NSURL *fileURL = [OGImageCache fileURLForKey:key];

From 6f0de0e9140a0d8b7ae7f092743f2e8f7d5879b8 Mon Sep 17 00:00:00 2001
From: Sixten Otto <opensource@sfko.com>
Date: Fri, 14 Mar 2014 15:56:37 -0700
Subject: [PATCH 11/14] handle invalid alpha options; creating bitmap context
 may fail

---
 OGImage/OGImageProcessing.m | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/OGImage/OGImageProcessing.m b/OGImage/OGImageProcessing.m
index 3d245d2..9bb454a 100644
--- a/OGImage/OGImageProcessing.m
+++ b/OGImage/OGImageProcessing.m
@@ -88,15 +88,21 @@ OSStatus UIImageToVImageBuffer(UIImage *image, vImage_Buffer *buffer, CGImageAlp
                                              buffer->width,
                                              buffer->height, 8,
                                              buffer->rowBytes, colorSpace, alphaInfo);
-    if (UIImageOrientationRight == image.imageOrientation) {
-        CGContextRotateCTM(ctx, -M_PI/2.f);
-        CGContextTranslateCTM(ctx, -(CGFloat)height, 0.f);
-    } else if (UIImageOrientationLeft == image.imageOrientation) {
-        CGContextRotateCTM(ctx, M_PI/2.f);
-        CGContextTranslateCTM(ctx, 0.f, -(CGFloat)width);
+    if (NULL == ctx) {
+        free(buffer->data);
+        buffer->data = NULL;
+        err = OGImageProcessingError;
+    } else {
+        if (UIImageOrientationRight == image.imageOrientation) {
+            CGContextRotateCTM(ctx, -M_PI/2.f);
+            CGContextTranslateCTM(ctx, -(CGFloat)height, 0.f);
+        } else if (UIImageOrientationLeft == image.imageOrientation) {
+            CGContextRotateCTM(ctx, M_PI/2.f);
+            CGContextTranslateCTM(ctx, 0.f, -(CGFloat)width);
+        }
+        CGContextDrawImage(ctx, CGRectMake(0.f, 0.f, CGImageGetWidth(cgImage), CGImageGetHeight(cgImage)), cgImage);
+        CGContextRelease(ctx);
     }
-    CGContextDrawImage(ctx, CGRectMake(0.f, 0.f, CGImageGetWidth(cgImage), CGImageGetHeight(cgImage)), cgImage);
-    CGContextRelease(ctx);
     CGColorSpaceRelease(colorSpace);
     return err;
 }
@@ -184,6 +190,9 @@ - (void)scaleImage:(__OGImage *)image toSize:(CGSize)size cornerRadius:(CGFloat)
             if (kCGImageAlphaNone == alphaInfo) {
                 // kCGImageAlphaNone w/8-bit channels not supported
                 alphaInfo = kCGImageAlphaNoneSkipLast;
+            } else if (kCGImageAlphaFirst == alphaInfo || kCGImageAlphaLast == alphaInfo) {
+                // non-premultiplied contexts are not supported
+                alphaInfo = kCGImageAlphaPremultipliedFirst;
             }
             if (0.f < cornerRadius) {
                 alphaInfo = kCGImageAlphaPremultipliedFirst;

From 0b5b96c8c89083e279a7d2b1950cafff8390120b Mon Sep 17 00:00:00 2001
From: Sixten Otto <opensource@sfko.com>
Date: Tue, 4 Nov 2014 12:52:33 -0700
Subject: [PATCH 12/14] update config for latest CocoaPods, update dependencies

---
 .../OGImageDemo.xcodeproj/project.pbxproj     | 27 +++++++++++++------
 .../OGImageTests/OGImageAssetsLibraryTests.m  |  2 +-
 OGImageDemo/OGImageTests/OGImageAsyncTests.m  |  2 +-
 OGImageDemo/OGImageTests/OGImageFileTests.m   |  2 +-
 .../OGImageTests/OGImageIdempotentTests.m     |  2 +-
 .../OGImageProblematicProcessingTests.m       |  2 +-
 .../OGImageTests/OGImageProcessingTests.m     |  2 +-
 .../OGImageTests/OGImageTestsAppDelegate.h    |  2 +-
 OGImageDemo/Podfile                           |  6 +++--
 9 files changed, 30 insertions(+), 17 deletions(-)

diff --git a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
index c8d8cf7..f252917 100644
--- a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
+++ b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
@@ -68,9 +68,10 @@
 
 /* Begin PBXFileReference section */
 		467479B3192A45B8984313B7 /* libPods.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libPods.a; sourceTree = BUILT_PRODUCTS_DIR; };
+		613EC03F3D03DD7743B0B058 /* Pods.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = Pods.release.xcconfig; path = "Pods/Target Support Files/Pods/Pods.release.xcconfig"; sourceTree = "<group>"; };
+		623F95686DC456957AC440BC /* Pods.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = Pods.debug.xcconfig; path = "Pods/Target Support Files/Pods/Pods.debug.xcconfig"; sourceTree = "<group>"; };
 		9C46672018D39709008960BA /* moldex-logo.gif */ = {isa = PBXFileReference; lastKnownFileType = image.gif; path = "moldex-logo.gif"; sourceTree = "<group>"; };
 		9C46672218D39EA7008960BA /* OGImageProblematicProcessingTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OGImageProblematicProcessingTests.m; sourceTree = "<group>"; };
-		9F932054786D4C9BA76B5EBE /* Pods.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = Pods.xcconfig; path = Pods/Pods.xcconfig; sourceTree = SOURCE_ROOT; };
 		C8030629166526A900073395 /* james_bond.json */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.json; name = james_bond.json; path = "Demo Data/james_bond.json"; sourceTree = "<group>"; };
 		C803062B1665295A00073395 /* OGImageTableViewCell.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGImageTableViewCell.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
 		C803062C1665295A00073395 /* OGImageTableViewCell.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGImageTableViewCell.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
@@ -163,6 +164,15 @@
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
+		18B84B7401884D0C718750AB /* Pods */ = {
+			isa = PBXGroup;
+			children = (
+				623F95686DC456957AC440BC /* Pods.debug.xcconfig */,
+				613EC03F3D03DD7743B0B058 /* Pods.release.xcconfig */,
+			);
+			name = Pods;
+			sourceTree = "<group>";
+		};
 		C80306271665269B00073395 /* Resources */ = {
 			isa = PBXGroup;
 			children = (
@@ -220,7 +230,7 @@
 				C871144416640E510015A743 /* OGImageTests */,
 				C88272171663DBDF007D409F /* Frameworks */,
 				C88272151663DBDF007D409F /* Products */,
-				9F932054786D4C9BA76B5EBE /* Pods.xcconfig */,
+				18B84B7401884D0C718750AB /* Pods */,
 			);
 			sourceTree = "<group>";
 		};
@@ -349,7 +359,7 @@
 			isa = PBXProject;
 			attributes = {
 				CLASSPREFIX = OG;
-				LastUpgradeCheck = 0450;
+				LastUpgradeCheck = 0610;
 				ORGANIZATIONNAME = "Origami Labs";
 			};
 			buildConfigurationList = C882720E1663DBDF007D409F /* Build configuration list for PBXProject "OGImageDemo" */;
@@ -414,7 +424,7 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "\"${SRCROOT}/Pods/Pods-resources.sh\"\n";
+			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods/Pods-resources.sh\"\n";
 		};
 /* End PBXShellScriptBuildPhase section */
 
@@ -494,7 +504,7 @@
 /* Begin XCBuildConfiguration section */
 		C871145616640E510015A743 /* Debug */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 9F932054786D4C9BA76B5EBE /* Pods.xcconfig */;
+			baseConfigurationReference = 623F95686DC456957AC440BC /* Pods.debug.xcconfig */;
 			buildSettings = {
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
@@ -507,7 +517,7 @@
 		};
 		C871145716640E510015A743 /* Release */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 9F932054786D4C9BA76B5EBE /* Pods.xcconfig */;
+			baseConfigurationReference = 613EC03F3D03DD7743B0B058 /* Pods.release.xcconfig */;
 			buildSettings = {
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
@@ -541,6 +551,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				IPHONEOS_DEPLOYMENT_TARGET = 6.0;
+				ONLY_ACTIVE_ARCH = YES;
 				OTHER_LDFLAGS = (
 					"-all_load",
 					"-ObjC",
@@ -579,7 +590,7 @@
 		};
 		C88272391663DBDF007D409F /* Debug */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 9F932054786D4C9BA76B5EBE /* Pods.xcconfig */;
+			baseConfigurationReference = 623F95686DC456957AC440BC /* Pods.debug.xcconfig */;
 			buildSettings = {
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
 				GCC_PREFIX_HEADER = "OGImageDemo/OGImageDemo-Prefix.pch";
@@ -591,7 +602,7 @@
 		};
 		C882723A1663DBDF007D409F /* Release */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 9F932054786D4C9BA76B5EBE /* Pods.xcconfig */;
+			baseConfigurationReference = 613EC03F3D03DD7743B0B058 /* Pods.release.xcconfig */;
 			buildSettings = {
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
 				GCC_PREFIX_HEADER = "OGImageDemo/OGImageDemo-Prefix.pch";
diff --git a/OGImageDemo/OGImageTests/OGImageAssetsLibraryTests.m b/OGImageDemo/OGImageTests/OGImageAssetsLibraryTests.m
index 0a71a11..71098e9 100644
--- a/OGImageDemo/OGImageTests/OGImageAssetsLibraryTests.m
+++ b/OGImageDemo/OGImageTests/OGImageAssetsLibraryTests.m
@@ -6,7 +6,7 @@
 //  Copyright (c) 2013 Origami Labs. All rights reserved.
 //
 
-#import "GHAsyncTestCase.h"
+#import <GHUnit/GHAsyncTestCase.h>
 #import "OGCachedImage.h"
 #import "OGImageCache.h"
 
diff --git a/OGImageDemo/OGImageTests/OGImageAsyncTests.m b/OGImageDemo/OGImageTests/OGImageAsyncTests.m
index 3d64c9e..619f65b 100644
--- a/OGImageDemo/OGImageTests/OGImageAsyncTests.m
+++ b/OGImageDemo/OGImageTests/OGImageAsyncTests.m
@@ -6,7 +6,7 @@
 //  Copyright (c) 2012 Origami Labs, Inc.. All rights reserved.
 //
 
-#import <GHUnitIOS/GHUnit.h>
+#import <GHUnit/GHUnit.h>
 #import "OGImage.h"
 #import "OGImageLoader.h"
 
diff --git a/OGImageDemo/OGImageTests/OGImageFileTests.m b/OGImageDemo/OGImageTests/OGImageFileTests.m
index 32a6e64..889b31f 100644
--- a/OGImageDemo/OGImageTests/OGImageFileTests.m
+++ b/OGImageDemo/OGImageTests/OGImageFileTests.m
@@ -6,7 +6,7 @@
 //  Copyright (c) 2013 Origami Labs. All rights reserved.
 //
 
-#import "GHAsyncTestCase.h"
+#import <GHUnit/GHAsyncTestCase.h>
 #import "OGCachedImage.h"
 #import "OGImageCache.h"
 
diff --git a/OGImageDemo/OGImageTests/OGImageIdempotentTests.m b/OGImageDemo/OGImageTests/OGImageIdempotentTests.m
index 2ffe697..1854416 100644
--- a/OGImageDemo/OGImageTests/OGImageIdempotentTests.m
+++ b/OGImageDemo/OGImageTests/OGImageIdempotentTests.m
@@ -6,7 +6,7 @@
 //  Copyright (c) 2013 Origami Labs. All rights reserved.
 //
 
-#import "GHAsyncTestCase.h"
+#import <GHUnit/GHAsyncTestCase.h>
 #import "OGImage.h"
 
 static NSString *KVOContext = @"OGImageIdempotentTests observation";
diff --git a/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m b/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
index 0b2b0da..e4dbdc5 100644
--- a/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
+++ b/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
@@ -7,7 +7,7 @@
 //
 
 #import <Accelerate/Accelerate.h>
-#import <GHUnitIOS/GHUnit.h>
+#import <GHUnit/GHUnit.h>
 #import "OGImageProcessing.h"
 #import "OGScaledImage.h"
 #import "OGImageCache.h"
diff --git a/OGImageDemo/OGImageTests/OGImageProcessingTests.m b/OGImageDemo/OGImageTests/OGImageProcessingTests.m
index fa982e0..3f2bbe1 100644
--- a/OGImageDemo/OGImageTests/OGImageProcessingTests.m
+++ b/OGImageDemo/OGImageTests/OGImageProcessingTests.m
@@ -6,7 +6,7 @@
 //  Copyright (c) 2012 Origami Labs, Inc.. All rights reserved.
 //
 
-#import <GHUnitIOS/GHUnit.h>
+#import <GHUnit/GHUnit.h>
 #import "OGImageProcessing.h"
 #import "OGScaledImage.h"
 #import "OGImageCache.h"
diff --git a/OGImageDemo/OGImageTests/OGImageTestsAppDelegate.h b/OGImageDemo/OGImageTests/OGImageTestsAppDelegate.h
index 4df5836..892bab6 100644
--- a/OGImageDemo/OGImageTests/OGImageTestsAppDelegate.h
+++ b/OGImageDemo/OGImageTests/OGImageTestsAppDelegate.h
@@ -6,7 +6,7 @@
 //  Copyright (c) 2013 Origami Labs. All rights reserved.
 //
 
-#import "GHUnitIOSAppDelegate.h"
+#import <GHUnit/GHUnitIOSAppDelegate.h>
 
 @interface OGImageTestsAppDelegate : GHUnitIOSAppDelegate
 
diff --git a/OGImageDemo/Podfile b/OGImageDemo/Podfile
index a7937e3..bac8ff6 100644
--- a/OGImageDemo/Podfile
+++ b/OGImageDemo/Podfile
@@ -1,4 +1,6 @@
-platform :ios
-pod 'GHUnitIOS', '~> 0.5.5'
+platform :ios, '6.0'
+source 'https://github.com/CocoaPods/Specs.git'
+
+pod 'GHUnit', '~> 0.5.8'
 pod 'CocoaLumberjack', '~> 1.6'
 

From 8b9984a95e942f665e300be5545dbd671012c6ca Mon Sep 17 00:00:00 2001
From: Sixten Otto <opensource@sfko.com>
Date: Tue, 4 Nov 2014 13:08:21 -0700
Subject: [PATCH 13/14] correct some 64-bit warnings

---
 OGImage/OGImageCache.m                                       | 2 +-
 OGImage/OGImageRequest.m                                     | 2 +-
 OGImage/OGScaledImage.m                                      | 2 +-
 OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/OGImage/OGImageCache.m b/OGImage/OGImageCache.m
index bc33a21..337e72a 100644
--- a/OGImage/OGImageCache.m
+++ b/OGImage/OGImageCache.m
@@ -41,7 +41,7 @@ + (OGImageCache *)shared {
 + (NSString *)MD5:(NSString *)string {
     const char *d = [string UTF8String];
     unsigned char r[CC_MD5_DIGEST_LENGTH];
-    CC_MD5(d, strlen(d), r);
+    CC_MD5(d, (CC_LONG)strlen(d), r);
     NSMutableString *hexString = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH];
     for (int ii = 0; ii < CC_MD5_DIGEST_LENGTH; ++ii) {
         [hexString appendFormat:@"%02x", r[ii]];
diff --git a/OGImage/OGImageRequest.m b/OGImage/OGImageRequest.m
index a666a87..0c6f695 100644
--- a/OGImage/OGImageRequest.m
+++ b/OGImage/OGImageRequest.m
@@ -75,7 +75,7 @@ - (void)prepareImageAndNotify {
         }
     } else {
         // if we get here, we have an http status code other than 200
-        tmpError = [NSError errorWithDomain:NSCocoaErrorDomain code:OGImageLoadingError userInfo:@{NSLocalizedDescriptionKey : [NSString stringWithFormat:@"OGImage: Received http status code: %d", _httpResponse.statusCode]}];
+        tmpError = [NSError errorWithDomain:NSCocoaErrorDomain code:OGImageLoadingError userInfo:@{NSLocalizedDescriptionKey : [NSString stringWithFormat:@"OGImage: Received http status code: %ld", (long)_httpResponse.statusCode]}];
     }
     NSAssert((nil == tmpImage && nil != tmpError) || (nil != tmpImage && nil == tmpError), @"One of tmpImage or tmpError should be non-nil");
     dispatch_async(dispatch_get_main_queue(), ^{
diff --git a/OGImage/OGScaledImage.m b/OGImage/OGScaledImage.m
index f7d9855..7ab6e12 100644
--- a/OGImage/OGScaledImage.m
+++ b/OGImage/OGScaledImage.m
@@ -9,7 +9,7 @@
 #import "OGImageCache.h"
 
 NSString *OGKeyWithSize(NSString *origKey, CGSize size, CGFloat cornerRadius, OGImageProcessingScaleMethod method) {
-    return [NSString stringWithFormat:@"%@-%f-%f-%f-%d", origKey, size.width, size.height, cornerRadius, method];
+    return [NSString stringWithFormat:@"%@-%f-%f-%f-%ld", origKey, size.width, size.height, cornerRadius, (long)method];
 }
 
 @implementation OGScaledImage {
diff --git a/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m b/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
index e4dbdc5..445a365 100644
--- a/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
+++ b/OGImageDemo/OGImageTests/OGImageProblematicProcessingTests.m
@@ -111,12 +111,12 @@ @implementation NoOpAssertionHandler
 
 - (void)handleFailureInMethod:(SEL)selector object:(id)object file:(NSString *)fileName lineNumber:(NSInteger)line description:(NSString *)format, ...
 {
-  NSLog(@"Assertion failure (ignored): %@ for object %@ in %@#%i", NSStringFromSelector(selector), object, fileName, line);
+  NSLog(@"Assertion failure (ignored): %@ for object %@ in %@#%li", NSStringFromSelector(selector), object, fileName, (long)line);
 }
 
 - (void)handleFailureInFunction:(NSString *)functionName file:(NSString *)fileName lineNumber:(NSInteger)line description:(NSString *)format, ...
 {
-  NSLog(@"Assertion failure (ignored): %@ in %@#%i", functionName, fileName, line);
+  NSLog(@"Assertion failure (ignored): %@ in %@#%li", functionName, fileName, (long)line);
 }
 
 @end

From 7ba6e16483fda3a055e6bc6667f36c0477d19b39 Mon Sep 17 00:00:00 2001
From: Sixten Otto <opensource@sfko.com>
Date: Tue, 4 Nov 2014 16:04:33 -0700
Subject: [PATCH 14/14] handle retina resolutions >2x

---
 OGImage/__OGImage.h                           |  15 +--
 OGImage/__OGImage.m                           |  34 +++++-
 .../OGImageDemo.xcodeproj/project.pbxproj     |   4 +
 OGImageDemo/OGImageTests/OGImageScaleTests.m  | 104 ++++++++++++++++++
 4 files changed, 144 insertions(+), 13 deletions(-)
 create mode 100644 OGImageDemo/OGImageTests/OGImageScaleTests.m

diff --git a/OGImage/__OGImage.h b/OGImage/__OGImage.h
index 872dff9..6973c42 100644
--- a/OGImage/__OGImage.h
+++ b/OGImage/__OGImage.h
@@ -18,16 +18,17 @@
  *
  * When you create an __OGImage with a fileURL or NSData instance, it uses the
  * Image I/O framework under the hood to find out about the file's format, metadata
- * and alpha. Additionally, if the file ends with the extension `.@2x`, __OGImage
- * will set UIImage's `scale` property correctly.
+ * and alpha. Additionally, if the file ends with an extension like `.@2x`,
+ * __OGImage will set UIImage's `scale` property correctly.
  *
  * When you save an __OGImage using `writeToURL`, it will automatically choose
  * the best format based on the current alpha properties and original file format.
- * Additionally, if the superclass' property `scale` is `2.f`, `writeToURL` will
- * automatically append the `.@2x` suffix. (Ultimately, this `.@2x` stuff is
- * an implementation detail: If you're not worried about cache internals, you
- * don't need to worry about this. Just use keys normally and `__OGImage` and
- * friends will figure everything out for you.
+ * Additionally, if the superclass' property `scale` is > 1, `writeToURL` will
+ * automatically append a resolution suffix like `.@2x`.
+ * 
+ * (Ultimately, this `.@2x` stuff is an implementation detail: If you're not
+ * worried about cache internals, you don't need to worry about this. Just use
+ * keys normally and `__OGImage` and friends will figure everything out for you.
  */
 
 @interface __OGImage : UIImage
diff --git a/OGImage/__OGImage.m b/OGImage/__OGImage.m
index 08451db..e265af5 100644
--- a/OGImage/__OGImage.m
+++ b/OGImage/__OGImage.m
@@ -35,17 +35,39 @@ UIImageOrientation OGEXIFOrientationToUIImageOrientation(NSInteger exif) {
     }
 }
 
+NSString *OGResolutionSuffixForScale(CGFloat scale) {
+  return [NSString stringWithFormat:@"@%.0fx", scale];
+}
+
 @implementation __OGImage
 
 - (id)initWithDataAtURL:(NSURL *)url {
     CGFloat scale = 1.f;
     if (NO == [[NSFileManager defaultManager] fileExistsAtPath:[url path]]) {
-        url = [url URLByAppendingPathExtension:@"@2x"];
-        if (NO == [[NSFileManager defaultManager] fileExistsAtPath:[url path]]) {
-            // no such file
+        // handling of scaled images is still limited, but at a practical level, the odds of seeing scale factors > 10 seem pretty long
+        // try to optimize by starting with screen rez of device
+        // possible that directory enumeration might be faster? but generally, hard to prove the negative proposition that there's no file
+        scale = [[UIScreen mainScreen] scale];
+        NSURL *scaledURL = [url URLByAppendingPathExtension:OGResolutionSuffixForScale(scale)];
+        if (YES == [[NSFileManager defaultManager] fileExistsAtPath:[scaledURL path]]) {
+            url = scaledURL;
+        }
+        else {
+            // no file at the device resolution; try others
+            // ??? or should we refuse to load images at mis-matched rez?
+            for (scale = 2.f; scale < 11.f; ++scale) {
+                if( scale != [[UIScreen mainScreen] scale] ) {
+                    scaledURL = [url URLByAppendingPathExtension:OGResolutionSuffixForScale(scale)];
+                    if (YES == [[NSFileManager defaultManager] fileExistsAtPath:[scaledURL path]]) {
+                        url = scaledURL;
+                        break;
+                    }
+                }
+            }
+        }
+        if( url != scaledURL ) {
             return nil;
         }
-        scale = 2.f;
     }
     NSData *data = [NSData dataWithContentsOfURL:url];
     return [self initWithData:data scale:scale];
@@ -114,8 +136,8 @@ - (BOOL)writeToURL:(NSURL *)fileURL error:(NSError **)error {
             imgType = @"public.jpeg";
         }
     }
-    if (2.f == self.scale) {
-        fileURL = [fileURL URLByAppendingPathExtension:@"@2x"];
+    if (1.f < self.scale) {
+        fileURL = [fileURL URLByAppendingPathExtension:OGResolutionSuffixForScale(self.scale)];
     }
     CGImageDestinationRef imageDestination = CGImageDestinationCreateWithURL((__bridge CFURLRef)fileURL, (__bridge CFStringRef)imgType, 1, NULL);
     if (NULL == imageDestination) {
diff --git a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
index f252917..bb18248 100644
--- a/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
+++ b/OGImageDemo/OGImageDemo.xcodeproj/project.pbxproj
@@ -64,6 +64,7 @@
 		C8975AEB166E09BB00C2D53A /* OGScaledImage.m in Sources */ = {isa = PBXBuildFile; fileRef = C8975AE9166E09BB00C2D53A /* OGScaledImage.m */; };
 		C8FADED9166D5DB100829179 /* Accelerate.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C8FADED8166D5DB100829179 /* Accelerate.framework */; };
 		C8FADEDB166D5DCA00829179 /* Accelerate.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C8FADED8166D5DB100829179 /* Accelerate.framework */; };
+		F68541041A096AED001D6727 /* OGImageScaleTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F68541031A096AED001D6727 /* OGImageScaleTests.m */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -130,6 +131,7 @@
 		C8975AE8166E09BB00C2D53A /* OGScaledImage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; lineEnding = 0; path = OGScaledImage.h; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objcpp; };
 		C8975AE9166E09BB00C2D53A /* OGScaledImage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = OGScaledImage.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
 		C8FADED8166D5DB100829179 /* Accelerate.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Accelerate.framework; path = System/Library/Frameworks/Accelerate.framework; sourceTree = SDKROOT; };
+		F68541031A096AED001D6727 /* OGImageScaleTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OGImageScaleTests.m; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -203,6 +205,7 @@
 				C87C645E16C46C70006217C9 /* OGImageIdempotentTests.m */,
 				C86E0BF01667FF9E006063B6 /* OGImageProcessingTests.m */,
 				9C46672218D39EA7008960BA /* OGImageProblematicProcessingTests.m */,
+				F68541031A096AED001D6727 /* OGImageScaleTests.m */,
 				C808967F1694ED01009BE21D /* OGImageTestsAppDelegate.h */,
 				C80896801694ED01009BE21D /* OGImageTestsAppDelegate.m */,
 			);
@@ -440,6 +443,7 @@
 				C8711466166417E20015A743 /* OGImageLoader.m in Sources */,
 				C80306351665421300073395 /* OGCachedImage.m in Sources */,
 				C86E0BED1667FE36006063B6 /* OGImageProcessing.m in Sources */,
+				F68541041A096AED001D6727 /* OGImageScaleTests.m in Sources */,
 				C86E0BF11667FF9E006063B6 /* OGImageProcessingTests.m in Sources */,
 				C86E0BF216680030006063B6 /* OGImageCache.m in Sources */,
 				C8975AEB166E09BB00C2D53A /* OGScaledImage.m in Sources */,
diff --git a/OGImageDemo/OGImageTests/OGImageScaleTests.m b/OGImageDemo/OGImageTests/OGImageScaleTests.m
new file mode 100644
index 0000000..e0b3ecc
--- /dev/null
+++ b/OGImageDemo/OGImageTests/OGImageScaleTests.m
@@ -0,0 +1,104 @@
+//
+//  OGImageScaleTests.m
+//  OGImageDemo
+//
+//  Created by Sixten Otto on 11/4/14.
+//  Copyright (c) 2014 Origami Labs. All rights reserved.
+//
+
+#import <GHUnit/GHUnit.h>
+#import "__OGImage.h"
+//#import "OGImageCache.h"
+
+@interface OGImageScaleTests : GHAsyncTestCase
+
+@property (strong, nonatomic) NSURL *destinationDirectoryURL;
+
+@end
+
+@implementation OGImageScaleTests
+
+- (void)setUp {
+  NSURL *tempDir = [[NSURL fileURLWithPath:NSTemporaryDirectory() isDirectory:YES] URLByAppendingPathComponent:@"OGImageScaleTests" isDirectory:YES];
+  if( ![[NSFileManager defaultManager] fileExistsAtPath:[tempDir path]] ) {
+    [[NSFileManager defaultManager] createDirectoryAtURL:tempDir withIntermediateDirectories:NO attributes:nil error:NULL];
+  }
+  self.destinationDirectoryURL = tempDir;
+  
+  //[[OGImageCache shared] purgeCache:YES];
+}
+
+- (void)tearDown {
+  [[NSFileManager defaultManager] removeItemAtURL:self.destinationDirectoryURL error:NULL];
+  //[[OGImageCache shared] purgeCache:YES];
+}
+
+- (UIImage *)newTestImageAtScale:(float)scale
+{
+  CGSize size = CGSizeMake(80, 17);
+  CGRect bounds = (CGRect){.origin=CGPointZero, .size=size};
+  UIGraphicsBeginImageContextWithOptions(size, YES, scale);
+  
+  [[UIColor whiteColor] setFill];
+  UIRectFill(bounds);
+  
+  CGFloat r = (arc4random_uniform(101) / 100.f),
+          g = (arc4random_uniform(101) / 100.f),
+          b = (arc4random_uniform(101) / 100.f);
+  [[UIColor colorWithRed:r green:g blue:b alpha:0.5f] setFill];
+  UIRectFill(bounds);
+  
+  [@"Lorem ipsum dolor sit amet" drawInRect:bounds withFont:[UIFont systemFontOfSize:15]];
+  
+  UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
+  UIGraphicsEndImageContext();
+  return result;
+}
+
+- (void)test1xImagesHaveNoExtension {
+  UIImage *testImg = [self newTestImageAtScale:1.0f];
+  __OGImage *img = [[__OGImage alloc] initWithCGImage:testImg.CGImage scale:testImg.scale orientation:UIImageOrientationUp];
+  NSURL *fileURL = [self.destinationDirectoryURL URLByAppendingPathComponent:@"one_echs_image.png"];
+  
+  BOOL success = [img writeToURL:fileURL error:NULL];
+  GHAssertTrue(success, @"Should successfully write to file.");
+  GHAssertTrue([[NSFileManager defaultManager] fileExistsAtPath:[fileURL path]], @"File should exist with unmodified name");
+}
+
+- (void)testRetinaImagesHaveResolutionExtensions {
+  for( CGFloat s = 2.0f; s < 6.0f; ++s ) {
+    UIImage *testImg = [self newTestImageAtScale:s];
+    __OGImage *img = [[__OGImage alloc] initWithCGImage:testImg.CGImage scale:s orientation:UIImageOrientationUp];
+    NSURL *fileURL = [self.destinationDirectoryURL URLByAppendingPathComponent:[[NSUUID UUID] UUIDString]];
+    NSURL *expectedFileURL = [fileURL URLByAppendingPathExtension:[NSString stringWithFormat:@"@%lix", (long)s]];
+    
+    BOOL success = [img writeToURL:fileURL error:NULL];
+    GHAssertTrue(success, @"Should successfully write to file.");
+    GHAssertFalse([[NSFileManager defaultManager] fileExistsAtPath:[fileURL path]], @"File should not exist with unmodified name at scale %.0f", s);
+    GHAssertTrue([[NSFileManager defaultManager] fileExistsAtPath:[expectedFileURL path]], @"File should exist with modified name at scale %.0f", s);
+  }
+}
+
+- (void)testImagesWithNoExtensionLoadedAs1x {
+  UIImage *testImg = [self newTestImageAtScale:1.0f];
+  NSURL *fileURL = [self.destinationDirectoryURL URLByAppendingPathComponent:@"one_echs_image.png"];
+  [UIImagePNGRepresentation(testImg) writeToURL:fileURL atomically:YES];
+  
+  __OGImage *img = [[__OGImage alloc] initWithDataAtURL:fileURL];
+  GHAssertNotNil(img, @"Should load the image.");
+  GHAssertEquals((CGFloat)1.0f, img.scale, @"Loaded image should be 1x");
+}
+
+- (void)testImagesWithResolutionExtensionsLoadedWithScale {
+  for( CGFloat s = 2.0f; s < 6.0f; ++s ) {
+    UIImage *testImg = [self newTestImageAtScale:s];
+    NSURL *fileURL = [self.destinationDirectoryURL URLByAppendingPathComponent:[[NSUUID UUID] UUIDString]];
+    [UIImagePNGRepresentation(testImg) writeToURL:[fileURL URLByAppendingPathExtension:[NSString stringWithFormat:@"@%lix", (long)s]] atomically:YES];
+    
+    __OGImage *img = [[__OGImage alloc] initWithDataAtURL:fileURL];
+    GHAssertNotNil(img, @"Should load the image at scale %.0f", s);
+    GHAssertEquals(s, img.scale, @"Loaded image should match scale %.0f", s);
+  }
+}
+
+@end