import AVFoundation
import Foundation
import Testing

@testable import HaishinKit

@Suite struct AudioRingBufferTests {
    @Test func monoAppendSampleBuffer_920() throws {
        try appendSampleBuffer(920, channels: 1)
    }

    @Test func monoAppendSampleBuffer_1024() throws {
        try appendSampleBuffer(1024, channels: 1)
    }

    @Test func monoAppendSampleBuffer_overrun() throws {
        let numSamples = 1024 * 4
        var asbd = AudioStreamBasicDescription(
            mSampleRate: 44100,
            mFormatID: kAudioFormatLinearPCM,
            mFormatFlags: 0xc,
            mBytesPerPacket: 2,
            mFramesPerPacket: 1,
            mBytesPerFrame: 2,
            mChannelsPerFrame: 1,
            mBitsPerChannel: 16,
            mReserved: 0
        )
        let format = AVAudioFormat(streamDescription: &asbd)
        let buffer = AudioRingBuffer(format!, bufferCounts: 3) // 1024 * 3
        guard
            let readBuffer = AVAudioPCMBuffer(pcmFormat: AVAudioFormat(streamDescription: &asbd)!, frameCapacity: AVAudioFrameCount(1024)),
            let sinWave = CMAudioSampleBufferFactory.makeSinWave(44100, numSamples: numSamples, channels: 1) else {
            return
        }
        buffer?.append(sinWave)
        #expect(buffer?.isDataAvailable(1024) == true)
        #expect(buffer?.render(UInt32(1024), ioData: readBuffer.mutableAudioBufferList) == noErr)
        #expect(buffer?.isDataAvailable(1024) == true)
        #expect(buffer?.render(UInt32(1024), ioData: readBuffer.mutableAudioBufferList) == noErr)
        #expect(buffer?.isDataAvailable(1024) == true)
        #expect(buffer?.render(UInt32(1024), ioData: readBuffer.mutableAudioBufferList) == noErr)
        #expect(buffer?.isDataAvailable(1024) == true)
        #expect(buffer?.render(UInt32(1024), ioData: readBuffer.mutableAudioBufferList) == noErr)
        #expect(buffer?.isDataAvailable(1024) == false)
        #expect(buffer?.render(UInt32(1024), ioData: readBuffer.mutableAudioBufferList) != noErr)
    }

    @Test func stereoAppendSampleBuffer_920() throws {
        try appendSampleBuffer(920, channels: 2)
    }

    @Test func stereoAppendSampleBuffer_1024() throws {
        try appendSampleBuffer(1024, channels: 2)
    }

    private func appendSampleBuffer(_ numSamples: Int, channels: UInt32) throws {
        var asbd = AudioStreamBasicDescription(
            mSampleRate: 44100,
            mFormatID: kAudioFormatLinearPCM,
            mFormatFlags: 0xc,
            mBytesPerPacket: 2 * channels,
            mFramesPerPacket: 1,
            mBytesPerFrame: 2 * channels,
            mChannelsPerFrame: channels,
            mBitsPerChannel: 16,
            mReserved: 0
        )
        let format = AVAudioFormat(streamDescription: &asbd)
        let buffer = AudioRingBuffer(format!, bufferCounts: 3)
        guard
            let readBuffer = AVAudioPCMBuffer(pcmFormat: AVAudioFormat(streamDescription: &asbd)!, frameCapacity: AVAudioFrameCount(numSamples)),
            let sinWave = CMAudioSampleBufferFactory.makeSinWave(44100, numSamples: numSamples, channels: channels) else {
            return
        }
        let bufferList = UnsafeMutableAudioBufferListPointer(readBuffer.mutableAudioBufferList)
        readBuffer.frameLength = AVAudioFrameCount(numSamples)
        for _ in 0..<30 {
            buffer?.append(sinWave)
            readBuffer.int16ChannelData?[0].update(repeating: 0, count: numSamples)
            #expect(buffer?.render(UInt32(numSamples), ioData: readBuffer.mutableAudioBufferList) == noErr)
            #expect(try sinWave.dataBuffer?.dataBytes().bytes == Data(bytes: bufferList[0].mData!, count: numSamples * Int(channels) * 2).bytes)
        }
    }
}