//...
    
    export class LocalProjectFile implements ProjectFile {
        private imageBinaryRepeater = new ReplaySubject<MSBaseReader>(1);
        private _identifier: Identifier;
    
        constructor(id: Identifier) {
            this._identifier = id;
        }
    
        private _selectedFile: Observable<File>;
    
        /**
         * This is the expected data structure that will
         * be translated as a rest call to the backend.
         * @returns {Observable<File>}
         */
        get selectedFile(): Observable<File> {
            return this._selectedFile;
        }
    
        set selectedFile(value: Observable<File>) {
            this._selectedFile = value;
            this.readFileIntoBinary();
        }
    
        /**
         * Sets current project file and also
         * reads the file into binary so that it
         * will be displayed.
         * @param {File} file preferably a image file.
         */
        setNewFile(file: File): void {
            this.selectedFile = Observable.of(file);
        }
    
        getIdentifier(): string {
            return this._identifier.id;
        }
    
        /**
         * This is the raw image data binary that
         * will be rendered by the browser.
         * @returns {Observable<MSBaseReader>}
         */
        imageBinary(): Observable<MSBaseReader> {
            return this.imageBinaryRepeater;
        }
    
        private readFileIntoBinary() {
            this._selectedFile
                .subscribe(file => {
                    let fileReader = new FileReader();
                    fileReader.onload = event => {
                        this.imageBinaryRepeater.next(fileReader.result);
                    };
                    fileReader.readAsDataURL(file);
                });
        }
    }