cog/Audio/Chain/AudioChunk.m

//
//  AudioChunk.m
//  CogAudio Framework
//
//  Created by Christopher Snowhill on 2/5/22.
//

#import "AudioChunk.h"

@implementation AudioChunk

- (id)init {
	self = [super init];

	if(self) {
		chunkData = [[NSMutableData alloc] init];
		formatAssigned = NO;
		lossless = NO;
	}

	return self;
}

@synthesize lossless;

- (AudioStreamBasicDescription)format {
	return format;
}

- (void)setFormat:(AudioStreamBasicDescription)informat {
	formatAssigned = YES;
	format = informat;
}

- (void)assignSamples:(const void *)data frameCount:(size_t)count {
	if(formatAssigned) {
		const size_t bytesPerPacket = format.mBytesPerPacket;
		[chunkData appendBytes:data length:bytesPerPacket * count];
	}
}

- (NSData *)removeSamples:(size_t)frameCount {
	if(formatAssigned) {
		const size_t bytesPerPacket = format.mBytesPerPacket;
		const size_t byteCount = bytesPerPacket * frameCount;
		NSData *ret = [chunkData subdataWithRange:NSMakeRange(0, byteCount)];
		[chunkData replaceBytesInRange:NSMakeRange(0, byteCount) withBytes:NULL length:0];
		return ret;
	}
	return [NSData data];
}

- (BOOL)isEmpty {
	return [chunkData length] == 0;
}

- (size_t)frameCount {
	if(formatAssigned) {
		const size_t bytesPerPacket = format.mBytesPerPacket;
		return [chunkData length] / bytesPerPacket;
	}
	return 0;
}

- (double)duration {
	if(formatAssigned) {
		const size_t bytesPerPacket = format.mBytesPerPacket;
		const double sampleRate = format.mSampleRate;
		return (double)([chunkData length] / bytesPerPacket) / sampleRate;
	}
	return 0.0;
}

@end