import type Feature from 'ol/Feature'
import { Style } from 'ol/style'
import type { ColorLike } from 'ol/colorlike'
import type { Size } from 'ol/size'

export interface Options {
  visible?: boolean;
  width?: number | ((feature: Feature, step: number) => number);
  width2?: number;
  color?: ColorLike | ((feature: Feature, step: number) => ColorLike);
  color2?: ColorLike;
  arrowClor?: ColorLike;
  lineCap: CanvasLineCap;
  arrowSize?: number | Size;
  arrow?: number;
  noOverlap?: boolean;
  offset0?: number;
  offset1?: number;
}

/** Flow line style
 * Draw LineString with a variable color / width
 * NB: the FlowLine style doesn't impress the hit-detection.
 * If you want your lines to be sectionable you have to add your own style to handle this.
 * (with transparent line: stroke color opacity to .1 or zero width)
 * @extends {ol_style_Style}
 * @constructor

 */
export default class FlowLine extends Style {
  /**
   * @param {Object} options
   *  @param {boolean} options.visible draw only the visible part of the line, default true
   *  @param {number|function} options.width Stroke width or a function that gets a feature and the position (beetween [0,1]) and returns current width
   *  @param {number} options.width2 Final stroke width (if width is not a function)
   *  @param {number} options.arrow Arrow at start (-1), at end (1), at both (2), none (0), default geta
   *  @param {ColorLike|function} options.color Stroke color or a function that gets a feature and the position (beetween [0,1]) and returns current color
   *  @param {ColorLike} options.color2 Final sroke color if color is nor a function
   *  @param {ColorLike} options.arrowColor Color of arrows, if not defined used color or color2
   *  @param {string} options.lineCap CanvasRenderingContext2D.lineCap 'butt' | 'round' | 'square', default 'butt'
   *  @param {number|ol.size} options.arrowSize height and width of the arrow, default 16
   *  @param {boolean} [options.noOverlap=false] prevent segments overlaping
   *  @param {number} options.offset0 offset at line start
   *  @param {number} options.offset1 offset at line end
   */
  constructor(options?: Options);

  /** Set the initial width
   * @param {number} width width, default 0
   */
  setWidth(width?: number): void;

  /** Set the final width
   * @param {number} width width, default 0
   */
  setWidth2(width?: number): void;

  /** Set the LineCap
   * @param {string} cap LineCap (round or butt), default butt
   */
  setLineCap(cap: 'round' | 'butt'): void;

  /** Get the current width at step
   * @param {feature} feature
   * @param {number} step current drawing step beetween [0,1]
   * @return {number}
   */
  getWidth(feature: Feature, step: number): number;

  /** Set the initial color
   * @param {colorLike} color
   */
  setColor(color: ColorLike): void;

  /** Set the final color
   * @param {colorLike} color
   */
  setColor2(color: ColorLike): void;

  /** Set the arrow color
   * @param {ol.colorLike} color
   */
  setArrowColor(color: ColorLike): void;

  getArrow(): number;

  /** Set arrow
   * @param {number} n -1 | 0 | 1 | 2, default: 0
   */
  setArrow(n: number): void;

  /** getArrowSize
   * @return {ol.size}
   */
  getArrowSize(): Size;

  /** setArrowSize
   * @param {number|ol.size} size
   */
  setArrowSize(size: number | Size): void;

  /** Get the current color at step
   * @param {feature} feature
   * @param {number} step current drawing step beetween [0,1]
   * @return {string}
   */
  getColor(feature: Feature, step: number): string;
}