/*

 Copyright (C) 2014 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

  Player view controller which sets up playback of movie file with metadata and uses AVPlayerItemMetadataOutput to render circle and text annotation during playback.

 */

@import AVFoundation;

#import "AAPLPlayerViewController.h"

#import "AAPLTimedAnnotationWriter.h"

#import "AAPLPlayerView.h"

@interface AAPLPlayerViewController () <AVPlayerItemMetadataOutputPushDelegate>

// Video track

@property AVAssetTrack      *videoTrack;

// Annotation state

@property CAShapeLayer      *circleLayer;

@property UILabel           *annotationText;

@property UIColor           *annotationColor;

@end

@implementation AAPLPlayerViewController

- (void)setupPlaybackWithURL:(NSURL *)movieURL

{

    if (!self.player)

    {

        // Set up player to preview the file which was just exported

        AVAsset *asset = [AVURLAsset assetWithURL:movieURL];

        [asset loadValuesAsynchronouslyForKeys:@[@"tracks"] completionHandler:^{

            // Get the first enabled video track in the asset.

            NSArray *videoTracks = [asset tracksWithMediaType:AVMediaTypeVideo];

            NSUInteger firstEnabledVideoTrackIndex = [videoTracks indexOfObjectPassingTest:^(id obj, NSUInteger idx, BOOL *stop)

            {

                AVAssetTrack *videoTrack = (AVAssetTrack *)obj;

                if ([videoTrack isEnabled])

                {

                    *stop = YES;

                    return YES;

                }

                return NO;

            }];

            if (firstEnabledVideoTrackIndex != NSNotFound)

            {

                self.videoTrack = [videoTracks objectAtIndex:firstEnabledVideoTrackIndex];

            }

        }];

        AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:asset];

        // Add player item metadata output to receive timed metadata groups during playback

        AVPlayerItemMetadataOutput *output = [[AVPlayerItemMetadataOutput alloc] initWithIdentifiers:nil];

        [output setDelegate:self queue:dispatch_get_main_queue()];

        [playerItem addOutput:output];

        self.player = [AVPlayer playerWithPlayerItem:playerItem];

        // Default annotation color is set to green

        self.annotationColor = [UIColor greenColor];

        // We use two finger tap to change the annotation color

        UITapGestureRecognizer *twoFingerTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(changeAnnotationColor:)];

        [twoFingerTap setNumberOfTouchesRequired:2];

        [self.view addGestureRecognizer:twoFingerTap];

    }

}

#pragma mark - AVPlayerItemMetadataOutputPushDelegate

- (void)metadataOutput:(AVPlayerItemMetadataOutput *)output didOutputTimedMetadataGroups:(NSArray *)groups fromPlayerItemTrack:(AVPlayerItemTrack *)track

{

    NSArray *referencedTracks = [[track assetTrack] associatedTracksOfType:AVTrackAssociationTypeMetadataReferent];

    if (![referencedTracks containsObject:self.videoTrack])

        return;

    for (AVTimedMetadataGroup *group in groups)

    {

        // Circle coordinate item

        AVMetadataItem *centerItem = [[AVMetadataItem metadataItemsFromArray:[group items] filteredByIdentifier:AAPLTimedAnnotationWriterCircleCenterCoordinateIdentifier] firstObject];

        // Circle radius item

        AVMetadataItem *radiusItem = [[AVMetadataItem metadataItemsFromArray:[group items] filteredByIdentifier:AAPLTimedAnnotationWriterCircleRadiusIdentifier] firstObject];

        // Annotation text item

        AVMetadataItem *textItem = [[AVMetadataItem metadataItemsFromArray:[group items] filteredByIdentifier:AAPLTimedAnnotationWriterCommentFieldIdentifier] firstObject];

        float radius = 0.0;

        CGPoint center = CGPointZero;

        NSString *commentText = nil;

        if (radiusItem.value)

            radius = [(NSNumber *)radiusItem.value floatValue];

        if (centerItem.value)

            center = CGPointMake([[(NSDictionary *)centerItem.value objectForKey:@"X"] floatValue], [[(NSDictionary *)centerItem.value objectForKey:@"Y"] floatValue]);

        if (textItem.value)

            commentText = textItem.stringValue;

        // Create CAShapeLayer which has gray rectangle with 0.5 opacity and circle (focus ring) of radius with 0 opacity

        // This shape layer is similar to the one drawn in updateCircleLayerWithCenter:radius:

        // Here we use the positioning information from AVPlayerItemMetadataOutput

        UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(-2000, -2000, self.view.bounds.size.width * 5, self.view.bounds.size.height * 5) cornerRadius:0];

        UIBezierPath *circlePath = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(center.x - radius, center.y - radius, 2.0*radius, 2.0*radius) cornerRadius:radius];

        [path appendPath:circlePath];

        [path setUsesEvenOddFillRule:YES];

        CAShapeLayer *fillLayer = [CAShapeLayer layer];

        fillLayer.path = path.CGPath;

        fillLayer.fillRule = kCAFillRuleEvenOdd;

        fillLayer.fillColor = [UIColor clearColor].CGColor;

        fillLayer.strokeColor = self.annotationColor.CGColor;

        fillLayer.lineWidth = 5;

        fillLayer.opacity = 0.5;

        [self.circleLayer removeFromSuperlayer];

        self.circleLayer = fillLayer;

        [self.circleLayer setHidden:NO];

        [self.view.layer addSublayer:self.circleLayer];

        UILabel *newAnnotationText = [[UILabel alloc] initWithFrame:CGRectMake(center.x + radius, center.y - radius, 200, 40)];

        newAnnotationText.text = commentText;

        newAnnotationText.textColor = [UIColor whiteColor];

        newAnnotationText.backgroundColor = self.annotationColor;

        newAnnotationText.textAlignment = NSTextAlignmentCenter;

        [self.annotationText removeFromSuperview];

        self.annotationText = newAnnotationText;

        [self.view addSubview:self.annotationText];

    }

}

#pragma mark - Gesture resognizer

- (void)changeAnnotationColor:(UITapGestureRecognizer *)recognizer

{

    // For every two finger tap we change the color of the annotation being drawn from green -> blue -> red -> green

    if ([self.annotationColor isEqual:[UIColor greenColor]])

    {

        self.annotationColor = [UIColor blueColor];

    }

    else if ([self.annotationColor isEqual:[UIColor blueColor]])

    {

        self.annotationColor = [UIColor redColor];

    }

    else if ([self.annotationColor isEqual:[UIColor redColor]])

    {

        self.annotationColor = [UIColor greenColor];

    }

    // Update circleLayer and annotationText color to match the new color

    self.circleLayer.strokeColor = self.annotationColor.CGColor;

    self.annotationText.backgroundColor = self.annotationColor;

}

@end