//
//  ViewController.swift
//  Convert images to movie format
//
//  Created by ryosuke-hujisawa on 2017/09/13.
//  Copyright © 2017年 ryosuke-hujisawa. All rights reserved.
//

import UIKit
import AVKit
import AVFoundation

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()





        let imageURL = Bundle.main.url(forResource: "ijustwannaknowyou", withExtension: "jpg")
        let videoSettings = CXEImageToVideoSync.videoSettings(codec: AVVideoCodecH264, width: 480, height: 320)
        let sync = CXEImageToVideoSync(videoSettings: videoSettings)
        let fileURL = sync.createMovieFrom(url: imageURL!, duration: 4)
        print(fileURL.absoluteString)
        let video = AVURLAsset(url: fileURL)
        print("duration: \(video.duration.seconds)")
//        let playItem = AVPlayerItem(asset: video)
//        self.player = AVPlayer(playerItem: playItem)
//        self.playerView.player = self.player




    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}

//
//  CXEImagesToVideoSync.swift
//  Convert images to movie format
//
//  Created by ryosuke-hujisawa on 2017/09/13.
//  Copyright © 2017年 ryosuke-hujisawa. All rights reserved.
//

import Foundation
import AVFoundation
import UIKit

fileprivate typealias CXEMovieMakerUIImageExtractor = (AnyObject) -> UIImage?


class CXEImageToVideoSync: NSObject{

    //MARK: Private Properties

    private var assetWriter:AVAssetWriter!
    private var writeInput:AVAssetWriterInput!
    private var bufferAdapter:AVAssetWriterInputPixelBufferAdaptor!
    private var videoSettings:[String : Any]!
    private var frameTime:CMTime!
    private var fileURL:URL!

    //MARK: Class Method

    class func videoSettings(codec:String, width:Int, height:Int) -> [String: Any]{
        if(Int(width) % 16 != 0){
            print("warning: video settings width must be divisible by 16")
        }

        let videoSettings:[String: Any] = [AVVideoCodecKey: AVVideoCodecH264,
                                           AVVideoWidthKey: width,
                                           AVVideoHeightKey: height]

        return videoSettings
    }

    //MARK: Public methods

    init(videoSettings: [String: Any]) {
        super.init()

        let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
        var tempPath:String
        repeat{
            let random = arc4random()
            tempPath = paths[0] + "/\(random).mp4"
        }while(FileManager.default.fileExists(atPath: tempPath))

        self.fileURL = URL(fileURLWithPath: tempPath)
        self.assetWriter = try! AVAssetWriter(url: self.fileURL, fileType: AVFileTypeQuickTimeMovie)

        self.videoSettings = videoSettings
        self.writeInput = AVAssetWriterInput(mediaType: AVMediaTypeVideo, outputSettings: videoSettings)
        assert(self.assetWriter.canAdd(self.writeInput), "add failed")

        self.assetWriter.add(self.writeInput)
        let bufferAttributes:[String: Any] = [kCVPixelBufferPixelFormatTypeKey as String: Int(kCVPixelFormatType_32ARGB)]
        self.bufferAdapter = AVAssetWriterInputPixelBufferAdaptor(assetWriterInput: self.writeInput, sourcePixelBufferAttributes: bufferAttributes)
        self.frameTime = CMTimeMake(600, 600)
    }

    func createMovieFrom(url: URL, duration:Int) -> URL{
        var urls = [URL]()
        var index = duration
        while(index > 0){
            urls.append(url)
            index -= 1
        }
        return self.createMovieFromSource(images: urls as [AnyObject], extractor:{(inputObject:AnyObject) ->UIImage? in
            return UIImage(data: try! Data(contentsOf: inputObject as! URL))})
    }

    func createMovieFrom(image: UIImage, duration:Int) -> URL{
        var images = [UIImage]()
        var index = duration
        while(index > 0){
            images.append(image)
            index -= 1
        }
        return self.createMovieFromSource(images: images, extractor: {(inputObject:AnyObject) -> UIImage? in
            return inputObject as? UIImage})
    }

    //MARK: Private methods

    private func createMovieFromSource(images: [AnyObject], extractor: @escaping CXEMovieMakerUIImageExtractor) -> URL{

        self.assetWriter.startWriting()
        //        self.assetWriter.startSession(atSourceTime: kCMTimeZero)
        let zeroTime = CMTimeMake(Int64(0),self.frameTime.timescale)
        self.assetWriter.startSession(atSourceTime: zeroTime)

        var i = 0
        let frameNumber = images.count

        while !self.writeInput.isReadyForMoreMediaData {}

        while(true){
            if(i >= frameNumber){
                break
            }

            if (self.writeInput.isReadyForMoreMediaData){
                var sampleBuffer:CVPixelBuffer?
                autoreleasepool{
                    let img = extractor(images[i])
                    if img == nil{
                        i += 1
                        print("Warning: counld not extract one of the frames")
                        //                            continue
                    }
                    sampleBuffer = self.newPixelBufferFrom(cgImage: img!.cgImage!)
                }
                if (sampleBuffer != nil){
                    if(i == 0){



                        /*
                        let time: CMTime = CMTimeMake(1000, 1000)
                        CMTimeMakeを用いて、valueとtimescaleを指定しての作成。上の例のvalue:1000, timescale:1000の場合、秒数でいうと10秒になる。


                        let time: CMTime = CMTimeMakeWithSeconds(Float64(7.6), 100)

                       */


                        //再生時間
                        let time: CMTime = CMTimeMake(0, 1000)

                        self.bufferAdapter.append(sampleBuffer!, withPresentationTime: time)


                        let timee: CMTime = CMTimeMake(5000, 1000)

                        self.bufferAdapter.append(sampleBuffer!, withPresentationTime: timee)


                    }else{
//                        let value = i - 1
//                        let lastTime = CMTimeMake(Int64(value), self.frameTime.timescale)
//                        let presentTime = CMTimeAdd(lastTime, self.frameTime)
//                        self.bufferAdapter.append(sampleBuffer!, withPresentationTime: presentTime)
                    }
                    i = i + 1
                }
            }
        }
        self.writeInput.markAsFinished()
        self.assetWriter.finishWriting {}

        var isSuccess:Bool = false
        while(!isSuccess){
            switch self.assetWriter.status {
            case .completed:
                isSuccess = true
                print("completed")
            case .writing:
                sleep(1)
                print("writing")
            case .failed:
                isSuccess = true
                print("failed")
            case .cancelled:
                isSuccess = true
                print("cancelled")
            default:
                isSuccess = true
                print("unknown")
            }
        }
        return self.fileURL
    }



    private func newPixelBufferFrom(cgImage:CGImage) -> CVPixelBuffer?{


        let options:[String: Any] = [kCVPixelBufferCGImageCompatibilityKey as String: true, kCVPixelBufferCGBitmapContextCompatibilityKey as String: true]

        var pxbuffer:CVPixelBuffer?
        let frameWidth = self.videoSettings[AVVideoWidthKey] as! Int
        let frameHeight = self.videoSettings[AVVideoHeightKey] as! Int

        let status = CVPixelBufferCreate(kCFAllocatorDefault, frameWidth, frameHeight, kCVPixelFormatType_32ARGB, options as CFDictionary?, &pxbuffer)

        assert(status == kCVReturnSuccess && pxbuffer != nil, "newPixelBuffer failed")

        CVPixelBufferLockBaseAddress(pxbuffer!, CVPixelBufferLockFlags(rawValue: 0))
        let pxdata = CVPixelBufferGetBaseAddress(pxbuffer!)
        let rgbColorSpace = CGColorSpaceCreateDeviceRGB()



        let context = CGContext(data: pxdata, width: frameWidth, height: frameHeight, bitsPerComponent: 8, bytesPerRow: CVPixelBufferGetBytesPerRow(pxbuffer!), space: rgbColorSpace, bitmapInfo: CGImageAlphaInfo.noneSkipFirst.rawValue)
        assert(context != nil, "context is nil")

        context!.concatenate(CGAffineTransform.identity)
        context!.draw(cgImage, in: CGRect(x: 0, y: 0, width: cgImage.width, height: cgImage.height))
        CVPixelBufferUnlockBaseAddress(pxbuffer!, CVPixelBufferLockFlags(rawValue: 0))


        print("pxbuffer!")
        print("pxbuffer!の方は \(type(of: pxbuffer!))です")
        print(pxbuffer!)

        return pxbuffer
    }
}