/*
Copyright 2018-2024 New Vector Ltd.
Copyright 2017 Vector Creations Ltd
Copyright 2015 OpenMarket Ltd

SPDX-License-Identifier: AGPL-3.0-only
Please see LICENSE in the repository root for full details.
 */

#import "MXKImageView.h"
#import "MXKPieChartView.h"
#import "MXKAttachment.h"

#import "MXKTools.h"

@interface MXKImageView ()
{
    NSString *mxcURI;
    NSString *mimeType;
    UIImageOrientation imageOrientation;
    
    // additional settings used in case of thumbnail.
    CGSize thumbnailViewSize;
    MXThumbnailingMethod thumbnailMethod;
    
    UIImage *currentImage;
    
    // the loading view is composed with the spinner and a pie chart
    // the spinner is display until progress > 0
    UIView *loadingView;
    UIActivityIndicatorView *waitingDownloadSpinner;
    MXKPieChartView *pieChartView;
    UILabel *progressInfoLabel;
    
    // validation buttons
    UIButton *leftButton;
    UIButton *rightButton;
    
    NSString *leftButtonTitle;
    NSString *rightButtonTitle;
    
    blockMXKImageView_onClick leftHandler;
    blockMXKImageView_onClick rightHandler;
    
    UIView* bottomBarView;
    
    // Subviews
    UIScrollView *scrollView;

    // Current attachment being displayed in the MXKImageView
    MXKAttachment *currentAttachment;
}
@end

@implementation MXKImageView
@synthesize stretchable, mediaFolder, imageView;

#define CUSTOM_IMAGE_VIEW_BUTTON_WIDTH 100

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    [self stopActivityIndicator];
    
    if (loadingView)
    {
        [loadingView removeFromSuperview];
        loadingView = nil;
    }
    
    if (bottomBarView)
    {
        [bottomBarView removeFromSuperview];
        bottomBarView = nil;
    }
    
    pieChartView = nil;
}

#pragma mark - Override MXKView

-(void)customizeViewRendering
{
    [super customizeViewRendering];
    
    self.backgroundColor = (_defaultBackgroundColor ? _defaultBackgroundColor : [UIColor blackColor]);
    
    self.contentMode = UIViewContentModeScaleAspectFit;
    self.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleTopMargin;
}

#pragma mark -

- (void)startActivityIndicator
{
    // create the views if they don't exist
    if (!waitingDownloadSpinner)
    {
        waitingDownloadSpinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];
        
        CGRect frame = waitingDownloadSpinner.frame;
        frame.size.width += 30;
        frame.size.height += 30;
        waitingDownloadSpinner.bounds = frame;
        [waitingDownloadSpinner.layer setCornerRadius:5];
    }
    
    if (!loadingView)
    {
        loadingView = [[UIView alloc] init];
        loadingView.frame = waitingDownloadSpinner.bounds;
        waitingDownloadSpinner.frame = waitingDownloadSpinner.bounds;
        [loadingView addSubview:waitingDownloadSpinner];
        loadingView.backgroundColor = [UIColor clearColor];
        [self addSubview:loadingView];
    }
    
    if (!pieChartView)
    {
        pieChartView = [[MXKPieChartView alloc] init];
        pieChartView.frame = loadingView.bounds;
        pieChartView.progress = 0;
        pieChartView.progressColor = [UIColor colorWithRed:1 green:1 blue:1 alpha:0.25];
        pieChartView.unprogressColor = [UIColor clearColor];
        
        [loadingView addSubview:pieChartView];
    }
    
    // display the download statistics
    if (_fullScreen && !progressInfoLabel)
    {
        progressInfoLabel = [[UILabel alloc] init];
        progressInfoLabel.backgroundColor = [UIColor whiteColor];
        progressInfoLabel.textColor = [UIColor blackColor];
        progressInfoLabel.font = [UIFont systemFontOfSize:8];
        progressInfoLabel.alpha = 0.25;
        progressInfoLabel.text = @"";
        progressInfoLabel.numberOfLines = 0;
        [progressInfoLabel sizeToFit];
        [self addSubview:progressInfoLabel];
    }
    
    // initvalue
    loadingView.hidden = NO;
    pieChartView.progress = 0;
    
    // Adjust color
    if ([self.backgroundColor isEqual:[UIColor blackColor]])
    {
        waitingDownloadSpinner.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhite;
        // a preview image could be displayed
        // ensure that the white spinner is visible
        // it could be drawn on a white area
        waitingDownloadSpinner.backgroundColor = [UIColor darkGrayColor];
        
    }
    else
    {
        waitingDownloadSpinner.activityIndicatorViewStyle = UIActivityIndicatorViewStyleGray;
    }
    
    // ensure that the spinner is drawn at the top
    [loadingView.superview bringSubviewToFront:loadingView];
    
    // Adjust position
    CGPoint center = CGPointMake(self.frame.size.width / 2, self.frame.size.height / 2);
    loadingView.center = center;
    
    // Start
    [waitingDownloadSpinner startAnimating];
}

- (void)stopActivityIndicator
{
    if (waitingDownloadSpinner && waitingDownloadSpinner.isAnimating)
    {
        [waitingDownloadSpinner stopAnimating];
    }
    
    pieChartView.progress = 0;
    loadingView.hidden = YES;
    
    if (progressInfoLabel)
    {
        [progressInfoLabel removeFromSuperview];
        progressInfoLabel = nil;
    }
}

#pragma mark - setters/getters

- (void)setDefaultBackgroundColor:(UIColor *)defaultBackgroundColor
{
    _defaultBackgroundColor = defaultBackgroundColor;
    [self customizeViewRendering];
}

- (void)setImage:(UIImage *)anImage
{
    // remove the observers
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    currentImage = anImage;
    imageView.image = anImage;

    [self initScrollZoomFactors];
}

- (UIImage*)image
{
    return currentImage;
}

- (void)showFullScreen
{
    // The full screen display mode is supported only if the shared application instance is available.
    UIApplication *sharedApplication = [UIApplication performSelector:@selector(sharedApplication)];
    if (sharedApplication)
    {
        _fullScreen = YES;
        
        [self initLayout];
        
        if (self.superview)
        {
            [super removeFromSuperview];
        }
        
        UIWindow *window = [sharedApplication keyWindow];
        
        self.frame = window.bounds;
        [window addSubview:self];
    }
}

#pragma mark -
- (IBAction)onButtonToggle:(id)sender
{
    if (sender == leftButton)
    {
        dispatch_async(dispatch_get_main_queue(), ^{
            self->leftHandler(self, self->leftButtonTitle);
        });
    }
    else if (sender == rightButton)
    {
        dispatch_async(dispatch_get_main_queue(), ^{
            self->rightHandler(self, self->rightButtonTitle);
        });
    }
}

// add a generic button to the bottom view
// return the added UIButton
- (UIButton*) addbuttonWithTitle:(NSString*)title
{
    UIButton* button = [[UIButton alloc] init];
    [button setTitle:title forState:UIControlStateNormal];
    [button setTitle:title forState:UIControlStateHighlighted];
    
    if (_fullScreen)
    {
        // use the same text color as the tabbar
        [button setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
        [button setTitleColor:[UIColor whiteColor] forState:UIControlStateHighlighted];
    }
    // TODO
    //    else {
    //        // use the same text color as the tabbar
    //        [button setTitleColor:[AppDelegate theDelegate].masterTabBarController.tabBar.tintColor forState:UIControlStateNormal];
    //        [button setTitleColor:[AppDelegate theDelegate].masterTabBarController.tabBar.tintColor forState:UIControlStateHighlighted];
    //    }
    
    // keep the bottomView background color
    button.backgroundColor = [UIColor clearColor];
    
    [button addTarget:self action:@selector(onButtonToggle:) forControlEvents:UIControlEventTouchUpInside];
    [bottomBarView addSubview:button];
    
    return button;
}

- (void)initScrollZoomFactors
{
    // check if the image can be zoomed
    if (self.image && self.stretchable && imageView.frame.size.width && imageView.frame.size.height)
    {
        // ensure that the content size is properly initialized
        scrollView.contentSize = scrollView.frame.size;
        
        // compute the appliable zoom factor
        // assume that the user does not expect to zoom more than 100%
        CGSize imageSize = self.image.size;
        
        CGFloat scaleX = imageSize.width  / imageView.frame.size.width;
        CGFloat scaleY = imageSize.height / imageView.frame.size.height;
        
        if (scaleX < scaleY)
        {
            scaleX = scaleY;
        }
        
        if (scaleX < 1.0)
        {
            scaleX = 1.0;
        }
        
        scrollView.zoomScale        = 1.0;
        scrollView.minimumZoomScale = 1.0;
        scrollView.maximumZoomScale = 3.0;
        
        // update the image frame to ensure that it fits to the scrollview frame
        imageView.frame = scrollView.bounds;
    }
}

- (void)removeFromSuperview
{
    [super removeFromSuperview];
    
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    if (pieChartView)
    {
        [self stopActivityIndicator];
    }
}

- (void)initLayout
{
    // create the subviews if they don't exist
    if (!scrollView)
    {
        scrollView = [[UIScrollView alloc] init];
        scrollView.delegate = self;
        scrollView.backgroundColor = [UIColor clearColor];
        [self addSubview:scrollView];
        
        imageView = [[UIImageView alloc] init];
        imageView.backgroundColor = [UIColor clearColor];
        imageView.userInteractionEnabled = YES;
        imageView.contentMode = self.contentMode;
        [scrollView addSubview:imageView];
    }
}

- (void)layoutSubviews
{
    // call upper layer
    [super layoutSubviews];
    
    [self initLayout];
    
    // the image has been updated
    if (imageView.image != self.image)
    {
        imageView.image = self.image;
    }
    
    CGRect tabBarFrame = CGRectZero;
    UITabBarController *tabBarController = nil;
    UIEdgeInsets safeAreaInsets = UIEdgeInsetsZero;
    
    if (leftButtonTitle || rightButtonTitle)
    {
        UIApplication *sharedApplication = [UIApplication performSelector:@selector(sharedApplication)];
        if (sharedApplication)
        {
            safeAreaInsets = [sharedApplication keyWindow].safeAreaInsets;

            UIViewController *rootViewController = [sharedApplication keyWindow].rootViewController;
            tabBarController = rootViewController.tabBarController;
            if (!tabBarController && [rootViewController isKindOfClass:[UITabBarController class]])
            {
                tabBarController = (UITabBarController*)rootViewController;
            }
        }
        
        if (tabBarController)
        {
            tabBarFrame = tabBarController.tabBar.frame;
        }
        else
        {
            // Define a default tabBar frame
            tabBarFrame = CGRectMake(0, 0, self.frame.size.width, 44 + safeAreaInsets.bottom);
        }
    }
    
    // update the scrollview frame
    CGRect oneSelfFrame = self.frame;
    CGRect scrollViewFrame = CGRectIntegral(scrollView.frame);
    
    if (leftButtonTitle || rightButtonTitle)
    {
        oneSelfFrame.size.height -= tabBarFrame.size.height;
    }
    
    oneSelfFrame = CGRectIntegral(oneSelfFrame);
    oneSelfFrame.origin = scrollViewFrame.origin = CGPointZero;
    
    // use integral rect to avoid rounded value issue (float precision)
    if (!CGRectEqualToRect(oneSelfFrame, scrollViewFrame))
    {
        scrollView.frame = oneSelfFrame;
        imageView.frame = oneSelfFrame;
        
        [self initScrollZoomFactors];
    }
    
    // check if the dedicated buttons are already added
    if (leftButtonTitle || rightButtonTitle)
    {
        
        if (!bottomBarView)
        {
            bottomBarView = [[UIView alloc] init];
            
            if (leftButtonTitle)
            {
                leftButton = [self addbuttonWithTitle:leftButtonTitle];
            }
            
            rightButton = [[UIButton alloc] init];
            
            if (rightButtonTitle)
            {
                rightButton = [self addbuttonWithTitle:rightButtonTitle];
            }
            
            // in fullscreen, display both buttons above the view (do the same if there is no tab bar)
            if (_fullScreen || tabBarController == nil)
            {
                bottomBarView.backgroundColor = [UIColor blackColor];
                [self addSubview:bottomBarView];
            }
            else
            {
                // default tabbar background color
                CGFloat base = 248.0 / 255.0f;
                bottomBarView.backgroundColor = [UIColor colorWithRed:base green:base blue:base alpha:1.0];
                
                // Display them over the tabbar
                [tabBarController.tabBar addSubview:bottomBarView];
            }
        }
        
        if (_fullScreen)
        {
            tabBarFrame.origin.y = self.frame.size.height - tabBarFrame.size.height;
        }
        else
        {
            tabBarFrame.origin.y = 0;
        }
        bottomBarView.frame = tabBarFrame;
        
        if (leftButton)
        {
            leftButton.frame = CGRectMake(safeAreaInsets.left, 0, CUSTOM_IMAGE_VIEW_BUTTON_WIDTH, bottomBarView.frame.size.height - safeAreaInsets.bottom);
        }
        
        if (rightButton)
        {
            rightButton.frame = CGRectMake(bottomBarView.frame.size.width - CUSTOM_IMAGE_VIEW_BUTTON_WIDTH - safeAreaInsets.right, 0, CUSTOM_IMAGE_VIEW_BUTTON_WIDTH, bottomBarView.frame.size.height - safeAreaInsets.bottom);
        }
    }
    
    if (!loadingView.hidden)
    {
        // ensure that the spinner is drawn at the top
        [loadingView.superview bringSubviewToFront:loadingView];
        
        // Adjust positions
        CGPoint center = CGPointMake(self.frame.size.width / 2, self.frame.size.height / 2);
        loadingView.center = center;
        
        CGRect progressInfoLabelFrame = progressInfoLabel.frame;
        progressInfoLabelFrame.origin.x = center.x - (progressInfoLabelFrame.size.width / 2);
        progressInfoLabelFrame.origin.y = 10 + loadingView.frame.origin.y + loadingView.frame.size.height;
        progressInfoLabel.frame = progressInfoLabelFrame;
    }
}

- (void)setHideActivityIndicator:(BOOL)hideActivityIndicator
{
    _hideActivityIndicator = hideActivityIndicator;
    if (hideActivityIndicator)
    {
        [self stopActivityIndicator];
    }
    else if (mxcURI)
    {
        NSString *downloadId = [MXMediaManager downloadIdForMatrixContentURI:mxcURI inFolder:mediaFolder];
        if ([MXMediaManager existingDownloaderWithIdentifier:downloadId])
        {
            // Loading is in progress, start activity indicator
            [self startActivityIndicator];
        }
    }
}

- (void)setImageURI:(NSString *)mxContentURI
           withType:(NSString *)mimeType
andImageOrientation:(UIImageOrientation)orientation
       previewImage:(UIImage*)previewImage
       mediaManager:(MXMediaManager*)mediaManager
{
    [self setImageURI:mxContentURI
             withType:mimeType
  andImageOrientation:orientation
          isThumbnail:NO
         previewImage:previewImage
         mediaManager:mediaManager];
}

- (void)setImageURI:(NSString *)mxContentURI
           withType:(NSString *)mimeType
andImageOrientation:(UIImageOrientation)orientation
      toFitViewSize:(CGSize)viewSize
         withMethod:(MXThumbnailingMethod)thumbnailingMethod
       previewImage:(UIImage*)previewImage
       mediaManager:(MXMediaManager*)mediaManager
{
    // Store the thumbnail settings
    thumbnailViewSize = viewSize;
    thumbnailMethod = thumbnailingMethod;
    
    [self setImageURI:mxContentURI
             withType:mimeType
  andImageOrientation:orientation
          isThumbnail:YES
         previewImage:previewImage
         mediaManager:mediaManager];
}

- (void)setImageURI:(NSString *)mxContentURI
           withType:(NSString *)mimeType
andImageOrientation:(UIImageOrientation)orientation
        isThumbnail:(BOOL)isThumbnail
       previewImage:(UIImage*)previewImage
       mediaManager:(MXMediaManager*)mediaManager
{
    // Remove any pending observers
    [[NSNotificationCenter defaultCenter] removeObserver:self];

    // Reset other data
    currentAttachment = nil;
    
    mxcURI = mxContentURI;
    if (!mxcURI)
    {
        // Set preview by default
        self.image = previewImage;
        return;
    }
    
    // Store image orientation
    imageOrientation = orientation;
    
    // Store the mime type used to define the cache path of the image.
    mimeType = mimeType;
    if (!mimeType.length)
    {
        // Set default mime type if no information is available
        mimeType = @"image/jpeg";
    }
    
    // Retrieve the image from cache if any
    NSString *cacheFilePath;
    if (isThumbnail)
    {
        cacheFilePath = [MXMediaManager thumbnailCachePathForMatrixContentURI:mxcURI
                                                                      andType:mimeType
                                                                     inFolder:mediaFolder
                                                                toFitViewSize:thumbnailViewSize
                                                                   withMethod:thumbnailMethod];
    }
    else
    {
        cacheFilePath = [MXMediaManager cachePathForMatrixContentURI:mxcURI
                                                             andType:mimeType
                                                            inFolder:mediaFolder];
    }
    
    UIImage* image = _enableInMemoryCache ? [MXMediaManager loadThroughCacheWithFilePath:cacheFilePath] : [MXMediaManager loadPictureFromFilePath:cacheFilePath];
    if (image)
    {
        if (imageOrientation != UIImageOrientationUp)
        {
            self.image = [UIImage imageWithCGImage:image.CGImage scale:1.0 orientation:imageOrientation];
        }
        else
        {
            self.image = image;
        }
        
        [self stopActivityIndicator];
    }
    else
    {
        // Set preview until the image is loaded
        self.image = previewImage;
        
        // Check whether the image download is in progress
        NSString *downloadId;
        if (isThumbnail)
        {
            downloadId = [MXMediaManager thumbnailDownloadIdForMatrixContentURI:mxcURI
                                                                       inFolder:mediaFolder
                                                                  toFitViewSize:thumbnailViewSize
                                                                     withMethod:thumbnailMethod];
        }
        else
        {
            downloadId = [MXMediaManager downloadIdForMatrixContentURI:mxcURI inFolder:mediaFolder];
        }
        
        MXMediaLoader* loader = [MXMediaManager existingDownloaderWithIdentifier:downloadId];
        if (!loader && mediaManager)
        {
            // Trigger the download
            if (isThumbnail)
            {
                loader = [mediaManager downloadThumbnailFromMatrixContentURI:mxcURI
                                                                    withType:mimeType
                                                                    inFolder:mediaFolder
                                                               toFitViewSize:thumbnailViewSize
                                                                  withMethod:thumbnailMethod
                                                                     success:nil
                                                                     failure:nil];
            }
            else
            {
                loader = [mediaManager downloadMediaFromMatrixContentURI:mxcURI
                                                                withType:mimeType
                                                                inFolder:mediaFolder];
            }
        }
        
        if (loader)
        {
            // update the progress UI with the current info
            if (!_hideActivityIndicator)
            {
                [self startActivityIndicator];
            }
            [self updateProgressUI:loader.statisticsDict];
            
            [[NSNotificationCenter defaultCenter] removeObserver:self name:kMXMediaLoaderStateDidChangeNotification object:loader];
            [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onMediaLoaderStateDidChange:) name:kMXMediaLoaderStateDidChangeNotification object:loader];
        }
    }
}

- (void)setAttachment:(MXKAttachment *)attachment
{
    // Remove any pending observers
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    // Set default orientation
    imageOrientation = UIImageOrientationUp;
    
    mediaFolder = attachment.eventRoomId;
    mxcURI = attachment.contentURL;
    mimeType = attachment.contentInfo[@"mimetype"];
    if (!mimeType.length)
    {
        // Set default mime type if no information is available
        mimeType = @"image/jpeg";
    }
    
    // while we wait for the content to download
    self.image = [attachment getCachedThumbnail];
    
    if (!_hideActivityIndicator)
    {
        [self startActivityIndicator];
    }

    currentAttachment = attachment;
    
    MXWeakify(self);
    [attachment getImage:^(MXKAttachment *attachment2, UIImage *img) {
        MXStrongifyAndReturnIfNil(self);

        if (self->currentAttachment != attachment2)
        {
            return;
        }

        self.image = img;
        [self stopActivityIndicator];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:kMXMediaLoaderStateDidChangeNotification object:nil];
    } failure:^(MXKAttachment *attachment2, NSError *error) {
        MXLogDebug(@"Unable to fetch image attachment! %@", error);
        MXStrongifyAndReturnIfNil(self);
        
        if (self->currentAttachment != attachment2)
        {
            return;
        }

        [self stopActivityIndicator];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:kMXMediaLoaderStateDidChangeNotification object:nil];
    }];
    
    // Check whether the image download is in progress
    NSString *downloadId = attachment.downloadId;
    MXMediaLoader* loader = [MXMediaManager existingDownloaderWithIdentifier:downloadId];
    if (loader)
    {
        // Observer this loader to display progress
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(checkProgressOnMediaLoaderStateChange:)
                                                     name:kMXMediaLoaderStateDidChangeNotification
                                                   object:loader];
    }
}

- (void)setAttachmentThumb:(MXKAttachment *)attachment
{
    // Remove any pending observers
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
    // Store image orientation
    imageOrientation = attachment.thumbnailOrientation;
    
    mediaFolder = attachment.eventRoomId;
    
    // Remove the existing image (if any) by using the potential preview.
    self.image = attachment.previewImage;
    
    if (!_hideActivityIndicator)
    {
        [self startActivityIndicator];
    }

    currentAttachment = attachment;
    
    MXWeakify(self);
    [attachment getThumbnail:^(MXKAttachment *attachment2, UIImage *img) {
        MXStrongifyAndReturnIfNil(self);
        
        dispatch_async(dispatch_get_main_queue(), ^{

            if (self->currentAttachment != attachment2)
            {
                return;
            }
            
            if (img && self->imageOrientation != UIImageOrientationUp)
            {
                self.image = [UIImage imageWithCGImage:img.CGImage scale:1.0 orientation:self->imageOrientation];
            }
            else
            {
                self.image = img;
            }
            [self stopActivityIndicator];
        });
            
    } failure:^(MXKAttachment *attachment2, NSError *error) {
        MXStrongifyAndReturnIfNil(self);
        
        dispatch_async(dispatch_get_main_queue(), ^{
            if (self->currentAttachment != attachment2)
            {
                return;
            }
            
            [self stopActivityIndicator];
        });
    }];
}

- (void)updateProgressUI:(NSDictionary*)downloadStatsDict
{
    // Sanity check: updateProgressUI may be called while there is no stats available
    // This happens when the download failed at the very beginning.
    if (nil == downloadStatsDict)
    {
        return;
    }
    
    NSNumber* progressNumber = [downloadStatsDict valueForKey:kMXMediaLoaderProgressValueKey];
    
    if (progressNumber)
    {
        pieChartView.progress = progressNumber.floatValue;
        waitingDownloadSpinner.hidden = YES;
    }
    
    if (progressInfoLabel)
    {
        NSNumber* downloadRate = [downloadStatsDict valueForKey:kMXMediaLoaderCurrentDataRateKey];
        
        NSNumber* completedBytesCount = [downloadStatsDict valueForKey:kMXMediaLoaderCompletedBytesCountKey];
        NSNumber* totalBytesCount = [downloadStatsDict valueForKey:kMXMediaLoaderTotalBytesCountKey];
        
        NSMutableString* text = [[NSMutableString alloc] init];

        if (completedBytesCount && totalBytesCount)
        {
            NSString* progressString = [NSString stringWithFormat:@"%@ / %@", [NSByteCountFormatter stringFromByteCount:completedBytesCount.longLongValue countStyle:NSByteCountFormatterCountStyleFile], [NSByteCountFormatter stringFromByteCount:totalBytesCount.longLongValue countStyle:NSByteCountFormatterCountStyleFile]];
            
            [text appendString:progressString];
        }
        
        if (downloadRate)
        {
            if (completedBytesCount && totalBytesCount)
            {
                CGFloat remainimgTime = ((totalBytesCount.floatValue - completedBytesCount.floatValue)) / downloadRate.floatValue;
                [text appendFormat:@" (%@)", [MXKTools formatSecondsInterval:remainimgTime]];
            }
            
            [text appendFormat:@"\n %@/s", [NSByteCountFormatter stringFromByteCount:downloadRate.longLongValue countStyle:NSByteCountFormatterCountStyleFile]];
        }
        
        progressInfoLabel.text = text;
        
        // on multilines, sizeToFit uses the current width
        // so reset it
        progressInfoLabel.frame = CGRectZero;
        
        [progressInfoLabel sizeToFit];
        
        //
        CGRect progressInfoLabelFrame = progressInfoLabel.frame;
        progressInfoLabelFrame.origin.x = self.center.x - (progressInfoLabelFrame.size.width / 2);
        progressInfoLabelFrame.origin.y = 10 + loadingView.frame.origin.y + loadingView.frame.size.height;
        progressInfoLabel.frame = progressInfoLabelFrame;
    }
}

- (void)onMediaLoaderStateDidChange:(NSNotification *)notif
{
    MXMediaLoader *loader = (MXMediaLoader*)notif.object;
    switch (loader.state) {
        case MXMediaLoaderStateDownloadInProgress:
            [self updateProgressUI:loader.statisticsDict];
            break;
        case MXMediaLoaderStateDownloadCompleted:
        {
            [self stopActivityIndicator];
            // update the image
            UIImage* image = [MXMediaManager loadPictureFromFilePath:loader.downloadOutputFilePath];
            if (image)
            {
                if (imageOrientation != UIImageOrientationUp)
                {
                    self.image = [UIImage imageWithCGImage:image.CGImage scale:1.0 orientation:imageOrientation];
                }
                else
                {
                    self.image = image;
                }
            }
            [[NSNotificationCenter defaultCenter] removeObserver:self name:kMXMediaLoaderStateDidChangeNotification object:loader];
            break;
        }
        case MXMediaLoaderStateDownloadFailed:
        case MXMediaLoaderStateCancelled:
            [self stopActivityIndicator];
            [[NSNotificationCenter defaultCenter] removeObserver:self name:kMXMediaLoaderStateDidChangeNotification object:loader];
            break;
        default:
            break;
    }
}

- (void)checkProgressOnMediaLoaderStateChange:(NSNotification *)notif
{
    MXMediaLoader *loader = (MXMediaLoader*)notif.object;
    switch (loader.state) {
        case MXMediaLoaderStateDownloadInProgress:
            [self updateProgressUI:loader.statisticsDict];
            break;
        default:
            break;
    }
}

#pragma mark - buttons management

- (void)setLeftButtonTitle: aLeftButtonTitle handler:(blockMXKImageView_onClick)handler
{
    leftButtonTitle = aLeftButtonTitle;
    leftHandler = handler;
}

- (void)setRightButtonTitle:aRightButtonTitle handler:(blockMXKImageView_onClick)handler
{
    rightButtonTitle = aRightButtonTitle;
    rightHandler = handler;
}

- (void)dismissSelection
{
    if (bottomBarView)
    {
        [bottomBarView removeFromSuperview];
        bottomBarView = nil;
    }
}

#pragma mark - UIScrollViewDelegate
// require to be able to zoom an image
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
    return self.stretchable ? imageView : nil;
}

// BWI: allow changing the image zoom level by double tab
- (void)toggleZoomLevel
{
    CGFloat currentZoomScale = scrollView.zoomScale;

    if (currentZoomScale < 1.5) {
        scrollView.zoomScale = 2.0;
    }
    else if (currentZoomScale < 2.5) {
        scrollView.zoomScale = 3.0;
    }
    else {
        scrollView.zoomScale = 1.0;
    }
}

@end