iOS Team / CNLiveImagePickerController · Files

//
//  ZLEditVideoController.m
//  ZLPhotoBrowser
//
//  Created by long on 2017/9/15.
//  Copyright © 2017年 long. All rights reserved.
//

#import "CNEditVideoController.h"
#import <AVFoundation/AVFoundation.h>
#import "TZAssetModel.h"
#import <objc/runtime.h>
#import <AssetsLibrary/AssetsLibrary.h>
#import "TZImagePickerController.h"
#import "TZPhotoPreviewCell.h"
#import "TZImageCropManager.h"

#define kItemWidth kItemHeight * 2/3
#define kItemHeight 50
#define kAPPName @"网++"

#pragma mark - 显示帧数的CNEditFrameView

@interface CNEditVideoCell : UICollectionViewCell

@property (nonatomic, strong) UIImageView *imageView;

@end

@implementation CNEditVideoCell

- (UIImageView *)imageView
{
    if (!_imageView) {
        _imageView = [[UIImageView alloc] init];
        _imageView.frame = self.bounds;
        _imageView.contentMode = UIViewContentModeScaleAspectFill;
        _imageView.clipsToBounds = YES;
        [self.contentView addSubview:_imageView];
    }
    return _imageView;
}

@end

#pragma mark - 协议编辑帧数协议CNEditFrameViewDelegate
@protocol CNEditFrameViewDelegate <NSObject>

- (void)editViewValidRectChanged;//有效范围更变

- (void)editViewValidRectEndChanged;//有效范围更变结束

@end

#pragma mark - 编辑时视图CNEditFrameView
@interface CNEditFrameView : UIView
{
    UIImageView *_leftView;//左视图
    UIImageView *_rightView;//有视图
}

@property (nonatomic, assign) CGRect validRect;
@property (nonatomic, weak) id<CNEditFrameViewDelegate> delegate;

@end

@implementation CNEditFrameView

- (instancetype)init
{
    self = [super init];
    if (self) {
        [self setupUI];
    }
    return self;
}

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
    //扩大下有效范围
    CGRect left = _leftView.frame;
    left.origin.x -= kItemWidth/2;
    left.size.width += kItemWidth/2;
    CGRect right = _rightView.frame;
    right.size.width += kItemWidth/2;
    
    if (CGRectContainsPoint(left, point)) {
        return _leftView;
    }
    if (CGRectContainsPoint(right, point)) {
        return _rightView;
    }
    return nil;
}

- (void)setupUI
{
    self.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:.5];
    self.layer.borderWidth = 2;
    self.layer.borderColor = [UIColor clearColor].CGColor;
    
    _leftView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"video_edit_left"]];
    _leftView.userInteractionEnabled = YES;
    _leftView.tag = 0;
    UIPanGestureRecognizer *lg = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panAction:)];
    [_leftView addGestureRecognizer:lg];
    [self addSubview:_leftView];
    
    _rightView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"video_edit_right"]];
    _rightView.userInteractionEnabled = YES;
    _rightView.tag = 1;
    UIPanGestureRecognizer *rg = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panAction:)];
    [_rightView addGestureRecognizer:rg];
    [self addSubview:_rightView];
}

- (void)panAction:(UIGestureRecognizer *)pan //滑动收拾实现
{
    self.layer.borderColor = [[UIColor whiteColor] colorWithAlphaComponent:.4].CGColor;
    CGPoint point = [pan locationInView:self];
    
    CGRect rct = self.validRect;
    
    const CGFloat W = self.frame.size.width;
    CGFloat minX = 0;
    CGFloat maxX = W;
    
    switch (pan.view.tag) {
        case 0: {
            //left视图响应
            maxX = rct.origin.x + rct.size.width - kItemWidth;
            
            point.x = MAX(minX, MIN(point.x, maxX));
            point.y = 0;
            
            rct.size.width -= (point.x - rct.origin.x);
            rct.origin.x = point.x;
        }
            break;
            
        case 1:
        {
            //right视图响应
            minX = rct.origin.x + kItemWidth/2;
            maxX = W - kItemWidth/2;
            
            point.x = MAX(minX, MIN(point.x, maxX));
            point.y = 0;
            
            rct.size.width = (point.x - rct.origin.x + kItemWidth/2);
        }
            break;
    }
    
    switch (pan.state) {
        case UIGestureRecognizerStateBegan:
        case UIGestureRecognizerStateChanged:
            if (self.delegate && [self.delegate respondsToSelector:@selector(editViewValidRectChanged)]) {
                [self.delegate editViewValidRectChanged];//滑动响应实现
            }
            break;
            
        case UIGestureRecognizerStateEnded:
        case UIGestureRecognizerStateCancelled:
            self.layer.borderColor = [UIColor clearColor].CGColor;
            if (self.delegate && [self.delegate respondsToSelector:@selector(editViewValidRectEndChanged)]) {
                [self.delegate editViewValidRectEndChanged];//滑动结束响应实现
            }
            break;
            
        default:
            break;
    }
    
    
    self.validRect = rct;
}

- (void)setValidRect:(CGRect)validRect//根据范围
{
    _validRect = validRect;
    _leftView.frame = CGRectMake(validRect.origin.x - kItemWidth/4, 0, kItemWidth/2, kItemHeight);
    _rightView.frame = CGRectMake(validRect.origin.x+validRect.size.width-kItemWidth/4, 0, kItemWidth/2, kItemHeight);
    
    [self setNeedsDisplay];
}

- (void)drawRect:(CGRect)rect
{
    CGContextRef context = UIGraphicsGetCurrentContext();
    
    CGContextClearRect(context, self.validRect);
    
    CGContextSetStrokeColorWithColor(context, [UIColor whiteColor].CGColor);
    CGContextSetLineWidth(context, 4.0);
    
    CGPoint topPoints[2];
    topPoints[0] = CGPointMake(self.validRect.origin.x, 0);
    topPoints[1] = CGPointMake(self.validRect.origin.x+self.validRect.size.width, 0);
    
    CGPoint bottomPoints[2];
    bottomPoints[0] = CGPointMake(self.validRect.origin.x, kItemHeight);
    bottomPoints[1] = CGPointMake(self.validRect.origin.x+self.validRect.size.width, kItemHeight);
    
    CGContextAddLines(context, topPoints, 2);
    CGContextAddLines(context, bottomPoints, 2);
    
    CGContextDrawPath(context, kCGPathStroke);
}

@end


#pragma mark - 编辑视频控制器CNEditVideoController
@interface CNEditVideoController () <UIScrollViewDelegate, UICollectionViewDataSource, UICollectionViewDelegate, CNEditFrameViewDelegate>
{
    UIView *_bottomView;
    UIButton *_cancelBtn;
    UIButton *_doneBtn;
    
    NSTimer *_timer;
    
    //下方collectionview偏移量
    CGFloat _offsetX;
    BOOL _orientationChanged;
    
    UIView *_indicatorLine;
    
    AVAsset *_avAsset;
    
    NSTimeInterval _interval;
    
    NSInteger _measureCount;
    NSOperationQueue *_queue;
    NSMutableDictionary<NSString *, UIImage *> *_imageCache;
    NSMutableDictionary<NSString *, NSBlockOperation *> *_opCache;
}

@property (nonatomic, strong) AVPlayerLayer *playerLayer;
@property (nonatomic, strong) UICollectionView *collectionView;
@property (nonatomic, strong) CNEditFrameView *editView;
@property (nonatomic, strong) AVAssetImageGenerator *generator;

@end

@implementation CNEditVideoController

- (void)dealloc
{
    [_queue cancelAllOperations];
    [self stopTimer];
    [[NSNotificationCenter defaultCenter] removeObserver:self];
//    NSLog(@"---- %s", __FUNCTION__);
}

- (AVAssetImageGenerator *)generator
{
    if (!_generator) {
        _generator = [[AVAssetImageGenerator alloc] initWithAsset:_avAsset];
        _generator.maximumSize = CGSizeMake(kItemWidth*4, kItemHeight*4);
        _generator.appliesPreferredTrackTransform = YES;
        _generator.requestedTimeToleranceBefore = kCMTimeZero;
        _generator.requestedTimeToleranceAfter = kCMTimeZero;
        _generator.apertureMode = AVAssetImageGeneratorApertureModeProductionAperture;
    }
    return _generator;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    [self setupUI];
    [self analysisAssetImages];
    
    _queue = [[NSOperationQueue alloc] init];
    _queue.maxConcurrentOperationCount = 3;
    
    _imageCache = [NSMutableDictionary dictionary];
    _opCache = [NSMutableDictionary dictionary];
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(deviceOrientationChanged:) name:UIApplicationWillChangeStatusBarOrientationNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(appResignActive) name:UIApplicationWillResignActiveNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(appBecomeActive) name:UIApplicationDidBecomeActiveNotification object:nil];
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    [UIApplication sharedApplication].statusBarHidden = YES;
    self.navigationController.navigationBar.hidden = YES;
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    self.navigationController.navigationBar.hidden = NO;
}

- (void)viewDidLayoutSubviews
{
    [super viewDidLayoutSubviews];
    
    UIEdgeInsets inset = UIEdgeInsetsZero;
    if (@available(iOS 11, *)) {
        inset = self.view.safeAreaInsets;
    }
    
    self.playerLayer.frame = CGRectMake(15, inset.top>0?inset.top:30, [UIScreen mainScreen].bounds.size.width-30, [UIScreen mainScreen].bounds.size.height-160-inset.bottom);
   
    self.editView.frame = CGRectMake(([UIScreen mainScreen].bounds.size.width-kItemWidth*10)/2, [UIScreen mainScreen].bounds.size.height-100-inset.bottom, kItemWidth*10, kItemHeight);
    self.editView.validRect = self.editView.bounds;
    self.collectionView.frame = CGRectMake(inset.left, [UIScreen mainScreen].bounds.size.height-100-inset.bottom, [UIScreen mainScreen].bounds.size.width-inset.left-inset.right, kItemHeight);
   
    CGFloat leftOffset = (([UIScreen mainScreen].bounds.size.width-kItemWidth*10)/2-inset.left);
    CGFloat rightOffset = (([UIScreen mainScreen].bounds.size.width-kItemWidth*10)/2-inset.right);
    [self.collectionView setContentInset:UIEdgeInsetsMake(0, leftOffset, 0, rightOffset)];
    [self.collectionView setContentOffset:CGPointMake(_offsetX-leftOffset, 0)];
    
    CGFloat bottomViewH = 44;
    CGFloat bottomBtnH = 30;
    _bottomView.frame = CGRectMake(0, [UIScreen mainScreen].bounds.size.height-bottomViewH-inset.bottom, [UIScreen mainScreen].bounds.size.width, kItemHeight);
    _cancelBtn.frame = CGRectMake(10+inset.left, 7, 60, bottomBtnH);
    _doneBtn.frame = CGRectMake([UIScreen mainScreen].bounds.size.width-70-inset.right, 7, 60, bottomBtnH);
    
    [self.playerLayer setBackgroundColor:[UIColor clearColor].CGColor];
}

#pragma mark - notifies
//设备旋转
- (void)deviceOrientationChanged:(NSNotification *)notify
{
    _offsetX = self.collectionView.contentOffset.x + self.collectionView.contentInset.left;
    _orientationChanged = YES;
}

- (void)appResignActive
{
    [self stopTimer];
}

- (void)appBecomeActive
{
    [self startTimer];
}

- (void)setupUI
{
    //禁用返回手势
    if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {
        self.navigationController.interactivePopGestureRecognizer.delegate = nil;
        self.navigationController.interactivePopGestureRecognizer.enabled = NO;
    }
    
    self.view.backgroundColor = [UIColor blackColor];
    
    self.playerLayer = [[AVPlayerLayer alloc] init];
    [self.view.layer addSublayer:self.playerLayer];
    
    UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];
    layout.itemSize = CGSizeMake(kItemWidth, kItemHeight);
    layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
    layout.minimumInteritemSpacing = 0;
    layout.minimumLineSpacing = 0;
    
    self.collectionView = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:layout];
    self.collectionView.delegate = self;
    self.collectionView.dataSource = self;
    self.collectionView.backgroundColor = [UIColor clearColor];
    self.collectionView.showsHorizontalScrollIndicator = NO;
    [self.collectionView registerClass:CNEditVideoCell.class forCellWithReuseIdentifier:@"CNEditVideoCell"];
    
    [self.view addSubview:self.collectionView];
    
    [self creatBottomView];
    
    self.editView = [[CNEditFrameView alloc] init];
    self.editView.delegate = self;
    [self.view addSubview:self.editView];
    
    _indicatorLine = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 2, kItemHeight)];
//    _indicatorLine.backgroundColor = [RGBOF(0x0BBE06) colorWithAlphaComponent:.7];
}

- (void)creatBottomView
{
    //下方视图
    _bottomView = [[UIView alloc] init];
    _bottomView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:.7];
    [self.view addSubview:_bottomView];
    
    _cancelBtn = [UIButton buttonWithType:UIButtonTypeCustom];
    _cancelBtn.titleLabel.font = [UIFont systemFontOfSize:15];
    [_cancelBtn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    [_cancelBtn setTitle:@"取消" forState:UIControlStateNormal];
    [_cancelBtn addTarget:self action:@selector(cancelBtn_click) forControlEvents:UIControlEventTouchUpInside];
    [_bottomView addSubview:_cancelBtn];
    
    _doneBtn = [UIButton buttonWithType:UIButtonTypeCustom];
    [_doneBtn setTitle:@"完成" forState:UIControlStateNormal];
    [_doneBtn setBackgroundColor:[UIColor clearColor]];
//    [_doneBtn setTitleColor:RGBOF(0x0BBE06) forState:UIControlStateNormal];
    _doneBtn.titleLabel.font = [UIFont systemFontOfSize:15];
    _doneBtn.layer.masksToBounds = YES;
    _doneBtn.layer.cornerRadius = 3.0f;
    [_doneBtn addTarget:self action:@selector(btnDone_click) forControlEvents:UIControlEventTouchUpInside];
    [_bottomView addSubview:_doneBtn];
}

#pragma mark - 解析视频每一帧图片
- (void)analysisAssetImages
{
    NSTimeInterval duration = 0.0;
    if ([self.model.asset isKindOfClass:[PHAsset class]]) {
        PHAsset *asset = self.model.asset;
        duration = asset.duration;
    }else if([self.model.asset isKindOfClass:[ALAsset class]]){
        duration = [[self.model.asset valueForProperty:ALAssetPropertyDuration] doubleValue];
    }
    
    TZImagePickerController *_tzImagePickerVc = (TZImagePickerController *)self.navigationController;
    _interval = _tzImagePickerVc.maxEditVideoTime/10.0;
    _measureCount = (NSInteger)(duration / _interval);
    ///播放视频的
    if ([self.model.asset isKindOfClass:[PHAsset class]]) {//PHAsset
        __weak typeof(self) weakSelf = self;
        [[PHCachingImageManager defaultManager] requestPlayerItemForVideo:self.model.asset options:nil resultHandler:^(AVPlayerItem * _Nullable playerItem, NSDictionary * _Nullable info) {
            dispatch_async(dispatch_get_main_queue(), ^{
                __strong typeof(weakSelf) strongSelf = weakSelf;
                if (!playerItem) return;
                AVPlayer *player = [AVPlayer playerWithPlayerItem:playerItem];
                strongSelf.playerLayer.player = player;
                [strongSelf startTimer];
            });
            
        }];
        
        ///截取视频帧数
        PHVideoRequestOptions* options = [[PHVideoRequestOptions alloc] init];
        options.version = PHVideoRequestOptionsVersionOriginal;
        options.deliveryMode = PHVideoRequestOptionsDeliveryModeAutomatic;
        options.networkAccessAllowed = YES;
        [[PHImageManager defaultManager] requestAVAssetForVideo:self.model.asset options:options resultHandler:^(AVAsset * _Nullable asset, AVAudioMix * _Nullable audioMix, NSDictionary * _Nullable info) {
            __strong typeof(weakSelf) strongSelf = weakSelf;
            strongSelf->_avAsset = asset;
            dispatch_async(dispatch_get_main_queue(), ^{
                [strongSelf.collectionView reloadData];
            });
        }];
        
    }else if([self.model.asset isKindOfClass:[ALAsset class]]){//ALAsset
        ///播放视频的
        ALAsset *alAsset = (ALAsset *)self.model.asset;
        ALAssetRepresentation *defaultRepresentation = [alAsset defaultRepresentation];
        NSString *uti = [defaultRepresentation UTI];
        NSURL *videoURL = [[alAsset valueForProperty:ALAssetPropertyURLs] valueForKey:uti];
        AVPlayerItem *playerItem = [[AVPlayerItem alloc] initWithURL:videoURL];
        AVPlayer *player = [AVPlayer playerWithPlayerItem:playerItem];
        self.playerLayer.player = player;
        [self startTimer];
        
        ///截取视频帧数
        NSURL *videoURL_al =[self.model.asset valueForProperty:ALAssetPropertyAssetURL]; // ALAssetPropertyURLs
        AVAsset *videoAsset = [AVURLAsset assetWithURL:videoURL];
        _avAsset = videoAsset ;
        [self.collectionView reloadData];

    }
  
}

#pragma mark - action
- (void)cancelBtn_click
{
    [self stopTimer];
    
    if (self.backButtonEditClickBlock) {
        TZImagePickerController *_tzImagePickerVc = (TZImagePickerController *)self.navigationController;
        self.backButtonEditClickBlock(_tzImagePickerVc.isSelectOriginalPhoto);
    }
    UIViewController *vc = [self.navigationController popViewControllerAnimated:NO];
    if (!vc) {
        [self dismissViewControllerAnimated:YES completion:nil];
    }
}

- (void)btnDone_click
{
    [self stopTimer];
    
    TZImagePickerController *_tzImagePickerVc = (TZImagePickerController *)self.navigationController;
    [_tzImagePickerVc showProgressHUD];
    
    [self exportEditVideoForAsset:_avAsset range:[self getTimeRange] complete:^(BOOL isSuc, id asset) {
        [_tzImagePickerVc hideProgressHUD];
        if (isSuc) {
            TZAssetModel *editModel = [TZAssetModel modelWithAsset:asset type:TZAssetModelMediaTypeVideo];
            
            // 如果没有选中过照片 点击确定时选中当前预览的照片
            if (_tzImagePickerVc.selectedModels.count == 0 && _tzImagePickerVc.minImagesCount <= 0) {
                [_tzImagePickerVc addSelectedModel:editModel];
            }
            
            if (self.doneButtonEditClickBlock) {
                self.doneButtonEditClickBlock(_tzImagePickerVc.isSelectOriginalPhoto);
            }
            [_tzImagePickerVc hideProgressHUD];
        }else{
            [_tzImagePickerVc showAlertWithTitle:@"编辑失败"];
        }
       
    }];
}
#pragma mark - 截取视频

- (void)exportEditVideoForAsset:(AVAsset *)asset range:(CMTimeRange)range complete:(void (^)(BOOL, id))complete
{
    [self export:asset range:range presetName:AVAssetExportPresetPassthrough renderSize:CGSizeZero imageSize:CGSizeZero effectImage:nil birthRate:0 velocity:0 complete:^(NSString *exportFilePath, NSError *error) {
        if (!error) {
            [self saveVideoToAblum:[NSURL fileURLWithPath:exportFilePath] completion:^(BOOL isSuc, id asset) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    if (complete) complete(isSuc, asset);
                });
            }];
        } else {
            dispatch_async(dispatch_get_main_queue(), ^{
                if (complete) complete(NO, nil);
            });
        }
    }];
}

///保存视频到相册
- (void)saveVideoToAblum:(NSURL *)url completion:(void (^)(BOOL, id))completion
{
    if (iOS8Later) {
        PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
        if (status == PHAuthorizationStatusDenied) {
            if (completion) completion(NO, nil);
        } else if (status == PHAuthorizationStatusRestricted) {
            if (completion) completion(NO, nil);
        } else {
            __block PHObjectPlaceholder *placeholderAsset=nil;
            [[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
                PHAssetChangeRequest *newAssetRequest = [PHAssetChangeRequest creationRequestForAssetFromVideoAtFileURL:url];
                placeholderAsset = newAssetRequest.placeholderForCreatedAsset;
            } completionHandler:^(BOOL success, NSError * _Nullable error) {
                if (!success) {
                    if (completion) completion(NO, nil);
                    return;
                }
                PHAsset *asset = [self getAssetFromlocalIdentifier:placeholderAsset.localIdentifier];
                PHAssetCollection *desCollection = [self getDestinationCollection];
                if (!desCollection) completion(NO, nil);
                
                [[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
                    [[PHAssetCollectionChangeRequest changeRequestForAssetCollection:desCollection] addAssets:@[asset]];
                } completionHandler:^(BOOL success, NSError * _Nullable error) {
                    if (completion) completion(success, asset);
                }];
            }];
        }
    }else{
        
        ALAssetsLibrary *assetLibrary = [[ALAssetsLibrary alloc] init];
        [assetLibrary writeVideoAtPathToSavedPhotosAlbum:url completionBlock:^(NSURL *assetURL, NSError *error) {
            if (error) {
                NSLog(@"保存视频出错:%@",error.localizedDescription);
                if (completion) {
                     completion(NO,nil);
                }
            } else {
                [assetLibrary assetForURL:assetURL resultBlock:^(ALAsset *asset) {
                    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
                        if (completion) {
                            completion(YES,asset);
                        }
                    });
                } failureBlock:^(NSError *error) {
                    
                    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
                        if (completion) {
                            completion(NO,nil);
                        }
                    });
                    
                }];
            }
        }];
        
    }
  
}

- (PHAsset *)getAssetFromlocalIdentifier:(NSString *)localIdentifier{
    if(localIdentifier == nil){
        NSLog(@"Cannot get asset from localID because it is nil");
        return nil;
    }
    PHFetchResult *result = [PHAsset fetchAssetsWithLocalIdentifiers:@[localIdentifier] options:nil];
    if(result.count){
        return result[0];
    }
    return nil;
}

//获取自定义相册
- (PHAssetCollection *)getDestinationCollection
{
    //找是否已经创建自定义相册
    PHFetchResult<PHAssetCollection *> *collectionResult = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
    for (PHAssetCollection *collection in collectionResult) {
        if ([collection.localizedTitle isEqualToString:kAPPName]) {
            return collection;
        }
    }
    //新建自定义相册
    __block NSString *collectionId = nil;
    NSError *error = nil;
    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
        collectionId = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:kAPPName].placeholderForCreatedAssetCollection.localIdentifier;
    } error:&error];
    if (error) {
        return nil;
    }
    return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[collectionId] options:nil].lastObject;
}

- (void)export:(AVAsset *)asset range:(CMTimeRange)range presetName:(NSString *)presetName renderSize:(CGSize)renderSize imageSize:(CGSize)imageSize effectImage:(UIImage *)effectImage birthRate:(NSInteger)birthRate velocity:(CGFloat)velocity complete:(void (^)(NSString *exportFilePath, NSError *error))complete
{
    NSString *exportFilePath = [self getVideoExportFilePath];
    
    AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:asset presetName:presetName];
    
    NSURL *exportFileUrl = [NSURL fileURLWithPath:exportFilePath];
    
    exportSession.outputURL = exportFileUrl;
    exportSession.outputFileType = AVFileTypeMPEG4;
    exportSession.timeRange = range;
    //        exportSession.shouldOptimizeForNetworkUse = YES;
    if (!CGSizeEqualToSize(renderSize, CGSizeZero)) {
        AVMutableVideoComposition *com = [self getVideoComposition:asset renderSize:renderSize imageSize:imageSize effectImage:effectImage birthRate:birthRate velocity:velocity];
        if (!com) {
            if (complete) {
                complete(nil, [NSError errorWithDomain:@"视频裁剪导出失败" code:-1 userInfo:@{@"message": @"视频对象格式可能有错误，没有检测到视频通道"}]);
            }
            return;
        }
        exportSession.videoComposition = com;
    }
    
    [exportSession exportAsynchronouslyWithCompletionHandler:^{
        BOOL suc = NO;
        switch ([exportSession status]) {
            case AVAssetExportSessionStatusFailed:
                NSLog(@"Export failed: %@", [[exportSession error] localizedDescription]);
                break;
            case AVAssetExportSessionStatusCancelled:
                NSLog(@"Export canceled");
                break;
                
            case AVAssetExportSessionStatusCompleted:{
                NSLog(@"Export completed");
                suc = YES;
            }
                break;
                
            default:
                NSLog(@"Export other");
                break;
        }
        
        if (complete) {
            complete(suc?exportFilePath:nil, suc?nil:exportSession.error);
            if (!suc) {
                [exportSession cancelExport];
            }
        }
    }];
}

- (NSString *)getVideoExportFilePath
{
    NSString *format = @"mp4";
    
    NSString *exportFilePath = [NSTemporaryDirectory() stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.%@", [self getUniqueStrByUUID], format]];
    
    return exportFilePath;
}

- (NSString *)getUniqueStrByUUID
{
    CFUUIDRef uuidObj = CFUUIDCreate(nil);//create a new UUID
    
    //get the string representation of the UUID
    CFStringRef uuidString = CFUUIDCreateString(nil, uuidObj);
    
    NSString *str = [NSString stringWithString:(__bridge NSString *)uuidString];
    
    CFRelease(uuidObj);
    CFRelease(uuidString);
    
    return [str lowercaseString];
}


- (AVMutableVideoComposition *)getVideoComposition:(AVAsset *)asset renderSize:(CGSize)renderSize imageSize:(CGSize)imageSize effectImage:(UIImage *)effectImage birthRate:(NSInteger)birthRate velocity:(CGFloat)velocity
{
    AVMutableComposition *composition = [AVMutableComposition composition];
    //视频通道
    AVMutableCompositionTrack *assetVideoTrack = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
    //音频通道
    AVMutableCompositionTrack *assetAudioTrack = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
    
    NSError *error = nil;
    //裁剪时长
    CMTimeRange timeRange = CMTimeRangeMake(kCMTimeZero, asset.duration);
    
    AVAssetTrack *videoTrack = [asset tracksWithMediaType:AVMediaTypeVideo].firstObject;//视频
    AVAssetTrack *audioTrack = [asset tracksWithMediaType:AVMediaTypeAudio].firstObject;//音频
    
    if (!videoTrack) {
        return nil;
    }
    [assetVideoTrack insertTimeRange:timeRange ofTrack:videoTrack atTime:kCMTimeZero error:&error];
    NSLog(@"%@", error);
    if (audioTrack) {
        [assetAudioTrack insertTimeRange:timeRange ofTrack:audioTrack atTime:kCMTimeZero error:&error];
        NSLog(@"%@", error);
    }
    
    if (error) {
        return nil;
    }
    
    AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
    instruction.timeRange = CMTimeRangeMake(kCMTimeZero, composition.duration);
    
    //处理视频旋转
    AVMutableVideoCompositionLayerInstruction *layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:assetVideoTrack];
    [layerInstruction setOpacity:0.0 atTime:assetVideoTrack.timeRange.duration];
    //视频旋转，获取视频旋转角度，然后旋转对应角度，保持视频方向正确
    CGFloat degree = [self getVideoDegree:videoTrack];
    CGSize naturalSize = assetVideoTrack.naturalSize;
    
    CGAffineTransform mixedTransform =  CGAffineTransformIdentity;
    //处理renderSize，不能大于视频宽高
    CGFloat videoWidth = (degree==0 || degree==M_PI) ? naturalSize.width : naturalSize.height;
    CGFloat videoHeight = (degree==0 || degree==M_PI) ? naturalSize.height : naturalSize.width;
    CGSize cropSize = CGSizeMake(MIN(videoWidth, renderSize.width), MIN(videoHeight, renderSize.height));
    CGFloat x, y;
    if (degree == M_PI_2) {
        //顺时针 90°
        CGAffineTransform t = CGAffineTransformMakeTranslation(naturalSize.height,.0);
        CGAffineTransform t1 = CGAffineTransformRotate(t, M_PI_2);
        //x为正向下 y为正向左
        x = -(videoHeight-cropSize.height)/2;
        y = (videoWidth-cropSize.width)/2;
        mixedTransform = CGAffineTransformTranslate(t1, x, y);
    } else if (degree == M_PI) {
        //顺时针 180°
        CGAffineTransform t = CGAffineTransformMakeTranslation(naturalSize.width, naturalSize.height);
        CGAffineTransform t1 = CGAffineTransformRotate(t, M_PI);
        //x为正向左 y为正向上
        x = (videoWidth-cropSize.width)/2;
        y = (videoHeight-cropSize.height)/2;
        mixedTransform = CGAffineTransformTranslate(t1, x, y);
    } else if (degree == (M_PI_2 * 3)) {
        //顺时针 270°
        CGAffineTransform t = CGAffineTransformMakeTranslation(.0, naturalSize.width);
        CGAffineTransform t1 = CGAffineTransformRotate(t, M_PI_2*3);
        //x为正向上 y为正向右
        x = (videoHeight-cropSize.height)/2;
        y = -(videoWidth-cropSize.width)/2;
        mixedTransform = CGAffineTransformTranslate(t1, x, y);
    } else {
        //x为正向右 y为正向下
        x = -(videoWidth-cropSize.width)/2;
        y = -(videoHeight-cropSize.height)/2;
        mixedTransform = CGAffineTransformMakeTranslation(x, y);
    }
    
    [layerInstruction setTransform:mixedTransform atTime:kCMTimeZero];
    
    //管理所有需要处理的视频
    AVMutableVideoComposition *videoComposition = [AVMutableVideoComposition videoComposition];
    videoComposition.frameDuration = CMTimeMake(1, 30);
    videoComposition.renderScale = 1;
    videoComposition.renderSize = cropSize;
    
    instruction.layerInstructions = @[layerInstruction];
    videoComposition.instructions = @[instruction];
    
    return videoComposition;
}

- (CGFloat)getVideoDegree:(AVAssetTrack *)videoTrack
{
    CGAffineTransform tf = videoTrack.preferredTransform;
    
    CGFloat degree = 0;
    if (tf.b == 1.0 && tf.c == -1.0) {
        degree = M_PI_2;
    } else if (tf.a == -1.0 && tf.d == -1.0) {
        degree = M_PI;
    } else if (tf.b == -1.0 && tf.c == 1.0) {
        degree = M_PI_2 * 3;
    }
    return degree;
}



#pragma mark - timer
- (void)startTimer
{
    [self stopTimer];
    
    CGFloat duration = _interval * self.editView.validRect.size.width / (kItemWidth);
    _timer = [NSTimer scheduledTimerWithTimeInterval:duration target:self selector:@selector(playPartVideo:) userInfo:nil repeats:YES];
    [_timer fire];
    [[NSRunLoop mainRunLoop] addTimer:_timer forMode:NSRunLoopCommonModes];
    
    _indicatorLine.frame = CGRectMake(self.editView.validRect.origin.x, 0, 4, kItemHeight);
    [self.editView addSubview:_indicatorLine];
    [UIView animateWithDuration:duration delay:.0 options:UIViewAnimationOptionRepeat|UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionCurveLinear animations:^{
        _indicatorLine.frame = CGRectMake(CGRectGetMaxX(self.editView.validRect)-2, 0, 2, kItemHeight);
    } completion:nil];
}

- (void)stopTimer
{
    [_timer invalidate];
    _timer = nil;
    [_indicatorLine removeFromSuperview];
    [self.playerLayer.player pause];
}

- (CMTime)getStartTime
{
    CGRect rect = [self.collectionView convertRect:self.editView.validRect fromView:self.editView];
    CGFloat s = MAX(0, _interval * rect.origin.x / (kItemWidth));
    return CMTimeMakeWithSeconds(s, self.playerLayer.player.currentTime.timescale);
}

- (CMTimeRange)getTimeRange
{
    CMTime start = [self getStartTime];
    CGFloat d = _interval * self.editView.validRect.size.width / (kItemWidth);
    CMTime duration = CMTimeMakeWithSeconds(d, self.playerLayer.player.currentTime.timescale);
    return CMTimeRangeMake(start, duration);
}

- (void)playPartVideo:(NSTimer *)timer
{
    [self.playerLayer.player play];
    [self.playerLayer.player seekToTime:[self getStartTime] toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero];
}

#pragma mark - edit view delegate
- (void)editViewValidRectChanged
{
    [self stopTimer];
    [self.playerLayer.player seekToTime:[self getStartTime] toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero];
}

- (void)editViewValidRectEndChanged
{
    [self startTimer];
}

#pragma mark - scroll view delegate
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    if (!self.playerLayer.player || _orientationChanged) {
        _orientationChanged = NO;
        return;
    }
    [self stopTimer];
    [self.playerLayer.player seekToTime:[self getStartTime] toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero];
}

- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
    if (!decelerate) {
        [self startTimer];
    }
}

- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
    [self startTimer];
}

#pragma mark - collection view data sources
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    return _measureCount;
}

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    CNEditVideoCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"CNEditVideoCell" forIndexPath:indexPath];
    
    UIImage *image = _imageCache[@(indexPath.row).stringValue];
    if (image) {
        cell.imageView.image = image;
    }
    
    return cell;
}

static const char _CNOperationCellKey;
- (void)collectionView:(UICollectionView *)collectionView willDisplayCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath
{
    if (!_avAsset) return;
    
    if (_imageCache[@(indexPath.row).stringValue] || _opCache[@(indexPath.row).stringValue]) {
        return;
    }
    
     NSBlockOperation *op = [NSBlockOperation blockOperationWithBlock:^{
        NSInteger row = indexPath.row;
        NSInteger i = row  * _interval;
        
        CMTime time = CMTimeMake((i+0.35) * _avAsset.duration.timescale, _avAsset.duration.timescale);
        
        NSError *error = nil;
        CGImageRef cgImg = [self.generator copyCGImageAtTime:time actualTime:NULL error:&error];
        if (!error && cgImg) {
            UIImage *image = [UIImage imageWithCGImage:cgImg];
            CGImageRelease(cgImg);

            [_imageCache setValue:image forKey:@(row).stringValue];

            dispatch_async(dispatch_get_main_queue(), ^{

                NSIndexPath *nowIndexPath = [collectionView indexPathForCell:cell];
                if (row == nowIndexPath.row) {
                    [(CNEditVideoCell *)cell imageView].image = image;
                } else {
                    UIImage *cacheImage = _imageCache[@(nowIndexPath.row).stringValue];
                    if (cacheImage) {
                        [(CNEditVideoCell *)cell imageView].image = cacheImage;
                    }
                }
            });
            [_opCache removeObjectForKey:@(row).stringValue];
        }
        objc_removeAssociatedObjects(cell);
    }];
    [_queue addOperation:op];
    [_opCache setValue:op forKey:@(indexPath.row).stringValue];
    
    objc_setAssociatedObject(cell, &_CNOperationCellKey, op, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (void)collectionView:(UICollectionView *)collectionView didEndDisplayingCell:(UICollectionViewCell *)cell forItemAtIndexPath:(NSIndexPath *)indexPath
{
    NSBlockOperation *op = objc_getAssociatedObject(cell, &_CNOperationCellKey);
    if (op) {
        [op cancel];
        objc_removeAssociatedObjects(cell);
        [_opCache removeObjectForKey:@(indexPath.row).stringValue];
    }
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end