SCRecordSessionSegment.m

//
//  SCRecordSessionSegment.m
//  SCRecorder
//
//  Created by Simon CORSIN on 10/03/15.
//  Copyright (c) 2015 rFlex. All rights reserved.
//

#import "SCRecordSessionSegment.h"
#import "SCRecordSession.h"

@interface SCRecordSessionSegment() {
    AVAsset *_asset;
    __weak UIImage *_thumbnail;
    __weak UIImage *_lastImage;
}

@end

@implementation SCRecordSessionSegment

- (instancetype)initWithDictionaryRepresentation:(NSDictionary *)dictionary directory:(NSString *)directory {
    NSString *filename = dictionary[SCRecordSessionSegmentFilenameKey];
    NSDictionary *info = dictionary[SCRecordSessionSegmentInfoKey];
    
    if (filename != nil) {
        NSURL *url = [SCRecordSessionSegment segmentURLForFilename:filename andDirectory:directory];
        return [self initWithURL:url info:info];
    }
    
    return nil;
}

- (instancetype)initWithURL:(NSURL *)url info:(NSDictionary *)info {
    self = [self init];
    
    if (self) {
        _url = url;
        _info = info;
    }
    
    return self;
}

- (void)deleteFile {
    NSError *error = nil;
    [[NSFileManager defaultManager] removeItemAtURL:_url error:&error];
    _url = nil;
    _asset = nil;
}

- (AVAsset *)asset {
    if (_asset == nil) {
        _asset = [AVAsset assetWithURL:_url];
    }
    
    return _asset;
}

- (CMTime)duration {
    return [self asset].duration;
}

- (UIImage *)thumbnail {
    UIImage *image = _thumbnail;
    if (image == nil) {
        AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc] initWithAsset:self.asset];
        imageGenerator.appliesPreferredTrackTransform = YES;
        
        NSError *error = nil;
        CGImageRef thumbnailImage = [imageGenerator copyCGImageAtTime:kCMTimeZero actualTime:nil error:&error];
        
        if (error == nil) {
            image = [UIImage imageWithCGImage:thumbnailImage];
            _thumbnail = image;
        } else {
            NSLog(@"Unable to generate thumbnail for %@: %@", self.url, error.localizedDescription);
        }
    }
    
    return image;
}

- (UIImage *)lastImage {
    UIImage *image = _lastImage;
    if (image == nil) {
        AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc] initWithAsset:self.asset];
        imageGenerator.appliesPreferredTrackTransform = YES;
        
        NSError *error = nil;
        CGImageRef lastImage = [imageGenerator copyCGImageAtTime:self.duration actualTime:nil error:&error];
        
        if (error == nil) {
            image = [UIImage imageWithCGImage:lastImage];
            _lastImage = image;
        } else {
            NSLog(@"Unable to generate lastImage for %@: %@", self.url, error.localizedDescription);
        }
    }
    
    return image;
}

- (float)frameRate {
    NSArray *tracks = [self.asset tracksWithMediaType:AVMediaTypeVideo];
    
    if (tracks.count == 0) {
        return 0;
    }
    
    AVAssetTrack *videoTrack = [tracks firstObject];
    
    return videoTrack.nominalFrameRate;
}

- (void)setUrl:(NSURL *)url {
    _url = url;
    _asset = nil;
}

- (NSDictionary *)dictionaryRepresentation {
    if (self.info == nil) {
        return @{ SCRecordSessionSegmentFilenameKey : self.url.lastPathComponent };
    } else {
        return @{
                 SCRecordSessionSegmentFilenameKey : self.url.lastPathComponent,
                 SCRecordSessionSegmentInfoKey : self.info
                 };
    }
}

- (BOOL)fileUrlExists {
    return [[NSFileManager defaultManager] fileExistsAtPath:self.url.path];
}

+ (NSURL *)segmentURLForFilename:(NSString *)filename andDirectory:(NSString *)directory {
    NSURL *directoryUrl = nil;
    
    if ([SCRecordSessionTemporaryDirectory isEqualToString:directory]) {
        directoryUrl = [NSURL fileURLWithPath:NSTemporaryDirectory()];
    } else if ([SCRecordSessionCacheDirectory isEqualToString:directory]) {
        NSArray *myPathList = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
        directoryUrl = [NSURL fileURLWithPath:myPathList.firstObject];
    } else if ([SCRecordSessionDocumentDirectory isEqualToString:directory]) {
        NSArray *myPathList = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        directoryUrl = [NSURL fileURLWithPath:myPathList.firstObject];
    } else {
        directoryUrl = [NSURL fileURLWithPath:directory];
    }
    
    return [directoryUrl URLByAppendingPathComponent:filename];
}

+ (SCRecordSessionSegment *)segmentWithURL:(NSURL *)url info:(NSDictionary *)info {
    return [[SCRecordSessionSegment alloc] initWithURL:url info:info];
}

@end