/**
 * Wrapper for pixel data of an image
 */
class PAImage {
  /**
   * Constructor
   * @param width width in pixel
   * @param height height in pixel
   * @param channels number of channels
   */
  constructor(width:number, height:number, channels: number) {
    this.width = width;
    this.height = height;
    this.channels = channels;
  }

  /**
   * Allocate memory for image data
   */
  allocateMemory() {
    this.pixels = new Uint8ClampedArray(this.width * this. height * this.channels);
  }

  /**
   * Set pixel data
   * @param pixels pixel data
   */
  setPixels(pixels : Uint8ClampedArray) {
    this.pixels = pixels;
  }

  /**
   * Get pixel data
   * @return pixel data
   */
  getPixels8() : Uint8ClampedArray {
    return this.pixels;
  }

  /**
   * Get width of image
   * @return width of image
   */
  getWidth() : number {
    return this.width;
  }

  /**
   * Get height of image
   * @return height of image
   */
  getHeight() : number {
    return this.height;
  }

  /**
   * Get number of channels
   * @return number of channels
   */
  getNumChannels() : number {
    return this.channels;
  }

  /**
   * Image width
   */
  private width: number; 
  /**
   * Image height
   */
  private height: number;
  /**
   * Number of channels
   */
  private channels: number;
  /**
   * Image data as RGBA 8 bit per channel
   */
  private pixels: Uint8ClampedArray;
};