featherVoice/TUIKit/TUIChat/CommonUI/Camera/TUIMovieManager.m

//  Created by Tencent on 2023/06/09.
//  Copyright © 2023 Tencent. All rights reserved.

#import "TUIMovieManager.h"
#import <TIMCommon/TIMDefine.h>

@interface TUIMovieManager () {
    BOOL _readyToRecordVideo;
    BOOL _readyToRecordAudio;
    dispatch_queue_t _movieWritingQueue;

    NSURL *_movieURL;
    AVAssetWriter *_movieWriter;
    AVAssetWriterInput *_movieAudioInput;
    AVAssetWriterInput *_movieVideoInput;
}

@end

@implementation TUIMovieManager

- (instancetype)init {
    self = [super init];
    if (self) {
        _movieWritingQueue = dispatch_queue_create("com.tui.Movie.Writing.Queue", DISPATCH_QUEUE_SERIAL);
        _movieURL = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@%@", NSTemporaryDirectory(), @"TUICaptureTempMovie.mp4"]];
        _referenceOrientation = AVCaptureVideoOrientationPortrait;
    }
    return self;
}

- (void)start:(void (^)(NSError *error))handle {
    @weakify(self);
    dispatch_async(_movieWritingQueue, ^{
      @strongify(self);
      [self removeFile:self->_movieURL];
      NSError *error;
      if (!self->_movieWriter) {
          self->_movieWriter = [[AVAssetWriter alloc] initWithURL:self->_movieURL fileType:AVFileTypeMPEG4 error:&error];
      }
      handle(error);
    });
}

- (void)stop:(void (^)(NSURL *url, NSError *error))handle {
    @weakify(self);
    dispatch_async(_movieWritingQueue, ^{
      @strongify(self);
      self->_readyToRecordVideo = NO;
      self->_readyToRecordAudio = NO;

      if (self->_movieWriter && self->_movieWriter.status == AVAssetWriterStatusWriting) {
          @weakify(self);
          [self->_movieWriter finishWritingWithCompletionHandler:^() {
            @strongify(self);
            @weakify(self);
            dispatch_async(dispatch_get_main_queue(), ^{
              @strongify(self);
              if (self->_movieWriter.status == AVAssetWriterStatusCompleted) {
                  handle(self->_movieURL, nil);
              } else {
                  handle(nil, self->_movieWriter.error);
              }
              self->_movieWriter = nil;
            });
          }];
      } else {
          [self->_movieWriter cancelWriting];
          self->_movieWriter = nil;
          dispatch_async(dispatch_get_main_queue(), ^{
            handle(nil, [NSError errorWithDomain:@"com.tui.Movie.Writing" code:0 userInfo:@{NSLocalizedDescriptionKey : @"AVAssetWriter status error"}]);
          });
      }
    });
}

- (void)writeData:(AVCaptureConnection *)connection video:(AVCaptureConnection *)video audio:(AVCaptureConnection *)audio buffer:(CMSampleBufferRef)buffer {
    CFRetain(buffer);
    @weakify(self);
    dispatch_async(_movieWritingQueue, ^{
      @strongify(self);
      if (connection == video) {
          if (!self->_readyToRecordVideo) {
              self->_readyToRecordVideo = [self setupAssetWriterVideoInput:CMSampleBufferGetFormatDescription(buffer)] == nil;
          }
          if ([self inputsReadyToRecord]) {
              [self writeSampleBuffer:buffer ofType:AVMediaTypeVideo];
          }
      } else if (connection == audio) {
          if (!self->_readyToRecordAudio) {
              self->_readyToRecordAudio = [self setupAssetWriterAudioInput:CMSampleBufferGetFormatDescription(buffer)] == nil;
          }
          if ([self inputsReadyToRecord]) {
              [self writeSampleBuffer:buffer ofType:AVMediaTypeAudio];
          }
      }
      CFRelease(buffer);
    });
}

- (void)writeSampleBuffer:(CMSampleBufferRef)sampleBuffer ofType:(NSString *)mediaType {
    if (_movieWriter.status == AVAssetWriterStatusUnknown) {
        if ([_movieWriter startWriting]) {
            [_movieWriter startSessionAtSourceTime:CMSampleBufferGetPresentationTimeStamp(sampleBuffer)];
        } else {
            NSLog(@"%@", _movieWriter.error);
        }
    }
    if (_movieWriter.status == AVAssetWriterStatusWriting) {
        if (mediaType == AVMediaTypeVideo) {
            if (!_movieVideoInput.isReadyForMoreMediaData) {
                return;
            }
            if (![_movieVideoInput appendSampleBuffer:sampleBuffer]) {
                NSLog(@"%@", _movieWriter.error);
            }
        } else if (mediaType == AVMediaTypeAudio) {
            if (!_movieAudioInput.isReadyForMoreMediaData) {
                return;
            }
            if (![_movieAudioInput appendSampleBuffer:sampleBuffer]) {
                NSLog(@"%@", _movieWriter.error);
            }
        }
    }
}

- (BOOL)inputsReadyToRecord {
    return _readyToRecordVideo && _readyToRecordAudio;
}

- (NSError *)setupAssetWriterAudioInput:(CMFormatDescriptionRef)currentFormatDescription {
    size_t aclSize = 0;
    const AudioStreamBasicDescription *currentASBD = CMAudioFormatDescriptionGetStreamBasicDescription(currentFormatDescription);
    const AudioChannelLayout *channelLayout = CMAudioFormatDescriptionGetChannelLayout(currentFormatDescription, &aclSize);
    NSData *dataLayout = aclSize > 0 ? [NSData dataWithBytes:channelLayout length:aclSize] : [NSData data];
    NSDictionary *settings = @{
        AVFormatIDKey : [NSNumber numberWithInteger:kAudioFormatMPEG4AAC],
        AVSampleRateKey : [NSNumber numberWithFloat:currentASBD->mSampleRate],
        AVChannelLayoutKey : dataLayout,
        AVNumberOfChannelsKey : [NSNumber numberWithInteger:currentASBD->mChannelsPerFrame],
        AVEncoderBitRatePerChannelKey : [NSNumber numberWithInt:64000]
    };

    if ([_movieWriter canApplyOutputSettings:settings forMediaType:AVMediaTypeAudio]) {
        _movieAudioInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeAudio outputSettings:settings];
        _movieAudioInput.expectsMediaDataInRealTime = YES;
        if ([_movieWriter canAddInput:_movieAudioInput]) {
            [_movieWriter addInput:_movieAudioInput];
        } else {
            return _movieWriter.error;
        }
    } else {
        return _movieWriter.error;
    }
    return nil;
}

- (NSError *)setupAssetWriterVideoInput:(CMFormatDescriptionRef)currentFormatDescription {
    CMVideoDimensions dimensions = CMVideoFormatDescriptionGetDimensions(currentFormatDescription);
    NSUInteger numPixels = dimensions.width * dimensions.height;
    CGFloat bitsPerPixel = numPixels < (640 * 480) ? 4.05 : 11.0;
    NSDictionary *compression =
        @{AVVideoAverageBitRateKey : [NSNumber numberWithInteger:numPixels * bitsPerPixel], AVVideoMaxKeyFrameIntervalKey : [NSNumber numberWithInteger:30]};
    NSDictionary *settings = @{
        AVVideoCodecKey : AVVideoCodecH264,
        AVVideoWidthKey : [NSNumber numberWithInteger:dimensions.width],
        AVVideoHeightKey : [NSNumber numberWithInteger:dimensions.height],
        AVVideoCompressionPropertiesKey : compression
    };

    if ([_movieWriter canApplyOutputSettings:settings forMediaType:AVMediaTypeVideo]) {
        _movieVideoInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:settings];
        _movieVideoInput.expectsMediaDataInRealTime = YES;
        _movieVideoInput.transform = [self transformFromCurrentVideoOrientationToOrientation:self.referenceOrientation];
        if ([_movieWriter canAddInput:_movieVideoInput]) {
            [_movieWriter addInput:_movieVideoInput];
        } else {
            return _movieWriter.error;
        }
    } else {
        return _movieWriter.error;
    }
    return nil;
}

- (CGAffineTransform)transformFromCurrentVideoOrientationToOrientation:(AVCaptureVideoOrientation)orientation {
    CGFloat orientationAngleOffset = [self angleOffsetFromPortraitOrientationToOrientation:orientation];
    CGFloat videoOrientationAngleOffset = [self angleOffsetFromPortraitOrientationToOrientation:self.currentOrientation];
    CGFloat angleOffset;
    if (self.currentDevice.position == AVCaptureDevicePositionBack) {
        angleOffset = videoOrientationAngleOffset - orientationAngleOffset + M_PI_2;
    } else {
        angleOffset = orientationAngleOffset - videoOrientationAngleOffset + M_PI_2;
    }
    CGAffineTransform transform = CGAffineTransformMakeRotation(angleOffset);
    return transform;
}

- (CGFloat)angleOffsetFromPortraitOrientationToOrientation:(AVCaptureVideoOrientation)orientation {
    CGFloat angle = 0.0;
    switch (orientation) {
        case AVCaptureVideoOrientationPortrait:
            angle = 0.0;
            break;
        case AVCaptureVideoOrientationPortraitUpsideDown:
            angle = M_PI;
            break;
        case AVCaptureVideoOrientationLandscapeRight:
            angle = -M_PI_2;
            break;
        case AVCaptureVideoOrientationLandscapeLeft:
            angle = M_PI_2;
            break;
    }
    return angle;
}

- (void)removeFile:(NSURL *)fileURL {
    NSFileManager *fileManager = [NSFileManager defaultManager];
    NSString *filePath = fileURL.path;
    if ([fileManager fileExistsAtPath:filePath]) {
        NSError *error;
        BOOL success = [fileManager removeItemAtPath:filePath error:&error];
        if (!success) {
            NSAssert(NO, error.localizedDescription);
            NSLog(@"Failed to delete file：%@", error);
        } else {
            NSLog(@"Succeed to delete file");
        }
    }
}

@end