//
// Copyright 2009-2011 Facebook
//
// Licensed 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.
//

// UI
#import "Three20UI/TTView.h"

// Network
#import "Three20Network/TTURLRequestDelegate.h"

@class TTURLRequest;
@protocol TTImageViewDelegate;

/**
 * A view that asynchronously loads an image and subsequently displays it.
 */
@interface TTImageView : TTView <TTURLRequestDelegate> {
  TTURLRequest* _request;
  NSString*     _urlPath;
  UIImage*      _image;
  UIImage*      _defaultImage;
  BOOL          _autoresizesToImage;

  id<TTImageViewDelegate> _delegate;
}

/**
 * The path of the image. This may be a web path (http://path/to/image.gif) or a local bundle
 * path (bundle://path/to/image.png).
 */
@property (nonatomic, copy) NSString* urlPath;

/**
 * The default image that is displayed until the image has been downloaded. If no urlPath is
 * specified, this image will be displayed indefinitely.
 */
@property (nonatomic, retain) UIImage* defaultImage;

/**
 * The image that is currently being displayed.
 */
@property (nonatomic, readonly) UIImage* image;

/**
 * Override the default sizing operation and resize the frame of this view with the size of
 * the image.
 *
 * @default NO
 */
@property (nonatomic) BOOL autoresizesToImage;

/**
 * Is an asynchronous request currently active?
 */
@property (nonatomic, readonly) BOOL isLoading;

/**
 * Has the image been successfully loaded?
 */
@property (nonatomic, readonly) BOOL isLoaded;

/**
 * A delegate that notifies you when the image has started and finished loading.
 */
@property (nonatomic, assign) id<TTImageViewDelegate> delegate;

/**
 * Cancel any pending request, remove the image, and redraw the view.
 */
- (void)unsetImage;

/**
 * Force the image to be reloaded. If the image is not in the cache, an asynchronous request is
 * sent off to fetch the image.
 */
- (void)reload;

/**
 * Cancel this image views' active asynchronous requests.
 */
- (void)stopLoading;

/**
 * Called when the image begins loading asynchronously.
 * Overridable method.
 *
 * @protected
 */
- (void)imageViewDidStartLoad;

/**
 * Called when the image finishes loading asynchronously.
 * Overridable method.
 *
 * @protected
 */
- (void)imageViewDidLoadImage:(UIImage*)image;

/**
 * Called when the image failed to load asynchronously.
 * Overridable method.
 *
 * @protected
 */
- (void)imageViewDidFailLoadWithError:(NSError*)error;

@end
