HelperMethods.swift

 func createDirectory(sourcePath: String, type: MediaType) {
        // path to documents directory
        let documentDirectoryPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first
        if let documentDirectoryPath = documentDirectoryPath {
            // create the custom folder path
            var subDirectoryPath = ""
            switch type
            {
            case .audio:
                subDirectoryPath = documentDirectoryPath.appending("/audios")
            case .video:
                subDirectoryPath = documentDirectoryPath.appending("/videos")
            case .image:
               subDirectoryPath = documentDirectoryPath.appending("/images")
            case .document:
               subDirectoryPath = documentDirectoryPath.appending("/documents")
            }
            let fileManager = FileManager.default
            if !fileManager.fileExists(atPath: subDirectoryPath) {
                do {
                    try fileManager.createDirectory(atPath: subDirectoryPath,
                                                    withIntermediateDirectories: false,
                                                    attributes: nil)
                    let fileName = sourcePath.components(separatedBy: "/").last
                    let destinationPath = subDirectoryPath.appending("/").appending(fileName!)
                    moveFileToDocumentsDir(sourcePath: sourcePath, desitinationPath: destinationPath)
                } catch {
                    print("Error creating images folder in documents dir: \(error)")
                }
            }
            else
            {
                print("Directory exists")
                let fileName = sourcePath.components(separatedBy: "/").last
                let destinationPath = subDirectoryPath.appending("/").appending(fileName!)
                moveFileToDocumentsDir(sourcePath: sourcePath, desitinationPath: destinationPath)
            }
        }
    }
    
    func moveFileToDocumentsDir(sourcePath: String, desitinationPath: String) {
        let filemgr = FileManager.default
        if !filemgr.fileExists(atPath: desitinationPath)
        {
            do {
                let startIndex = sourcePath.index(sourcePath.startIndex, offsetBy: 7)
                let trimmedSourcePath = sourcePath[startIndex...]
                try filemgr.moveItem(atPath: String(trimmedSourcePath), toPath: desitinationPath)
            }catch let error {
                print("Error: \(error.localizedDescription)")
            }
        }
        else
        {
            print("file exists")
        }
    }
    
    func getFilesFromDoucmentDir(type: MediaType)
    {
        // path to documents directory
        let documentDirectoryPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first
        if let documentDirectoryPath = documentDirectoryPath {
            // create the custom folder path
            var subDirectoryPath = ""
            switch type
            {
            case .audio:
                subDirectoryPath = documentDirectoryPath.appending("/audios")
            case .video:
                subDirectoryPath = documentDirectoryPath.appending("/videos")
            case .image:
                subDirectoryPath = documentDirectoryPath.appending("/images")
            case .document:
                subDirectoryPath = documentDirectoryPath.appending("/documents")
            }
            print(subDirectoryPath)
            let fileManager = FileManager.default
            do {
                let fileURLs = try fileManager.contentsOfDirectory(at: URL.init(string: subDirectoryPath)! , includingPropertiesForKeys: nil)
                
                for file in fileURLs
                {
                    if !file.absoluteString.contains("DS_Store")
                    {
                    var image = NSImage()
                    switch type
                    {
                    case .audio:
                        image = #imageLiteral(resourceName: "music-player")
                    case .video:
                        image = #imageLiteral(resourceName: "video-player")
                    case .document:
                        image = #imageLiteral(resourceName: "file")
                    case .image:
                        if let i = NSImage(contentsOf: file)
                        {
                            image = i
                        }
                    }
                    let name = String(describing: file).components(separatedBy: "/").last
                    let media = Media(image: image, url: file)
                    files[name!] = media
                    nothingFoundLabel.isHidden = true
                }
                }
                if Array(files.keys).count < 1
                {
                    nothingFoundLabel.isHidden = false
                }
                
            } catch {
                nothingFoundLabel.isHidden = false
                print("Error while enumerating files : \(error.localizedDescription)")
            }
            collectionView.reloadData()
        }
    }