export interface Options {
  file?: File;
  chunkSize?: number;
}

/** Text file reader (chunk by chunk, line by line).
 * Large files are read in chunks and returned line by line
 * to handle read progress and prevent memory leaks.

 */
export default class TextStreamReader {
  /**
   * @param {Object} options
   *  @param {File} [options.file]
   *  @param {number} [options.chunkSize=1E6]
   */
  constructor(options?: Options);

  /** Set file to read
   * @param {File} file
   */
  setFile(file: File): void;

  /** Sets the file position indicator to the beginning of the file stream.
   */
  rewind(): void;

  /** Set reader chunk size
   * @param {number} [chunkSize=1E6]
   */
  setChunkSize(s: any): void;

  /** Get progress
   * @return {number} progress [0,1]
   */
  getProgress(): number;

  /** Read a text file line by line from the start
   * @param {function} getLine a function that gets the current line as argument. Return false to stop reading
   * @param {function} [progress] a function that gets the progress on each chunk (beetween 0,1) and a boolean set to true on end
   */
  readLines(getLine: (line: string) => void, progress?: (arg0: number, arg1: boolean) => void): void;

  /** Read a set of line chunk from the stream
   * @param {function} getLines a function that gets lines read as an Array<String>.
   * @param {function} [progress] a function that gets the progress (beetween 0,1) and a boolean set to true on end of file
   */
  readChunk(getLines: (lines: string[]) => void, progress?: (arg0: number, arg1: boolean) => void): void
}