@inweb/markup/src/markup/Konva/KonvaImage.ts

JavaScript 2D markups

import Konva from "konva";
import { IMarkupImage, IMarkupImageParams } from "../IMarkupImage";

export class KonvaImage implements IMarkupImage {
  private _ref: Konva.Image;
  private _canvasImage: HTMLImageElement;
  private _ratio = 1;
  private readonly EPSILON = 10e-6;
  private readonly BASE64_HEADER_START = "data:image/";
  private readonly BASE64_NOT_FOUND =
    "data:image/jpeg;base64,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";

  constructor(params: IMarkupImageParams, ref = null) {
    if (ref) {
      if (!ref.src || !ref.src.startsWith(this.BASE64_HEADER_START)) ref.src = this.BASE64_NOT_FOUND;
      if (ref.height() <= this.EPSILON) ref.height(32);
      if (ref.width() <= this.EPSILON) ref.width(32);

      this._ref = ref;
      this._canvasImage = ref.image();
      this._ratio =
        this._ref.height() <= this.EPSILON || this._ref.width() <= this.EPSILON
          ? 1
          : this._ref.height() / this._ref.width();

      return;
    }

    if (!params) params = {};
    if (!params.position) params.position = { x: 0, y: 0 };
    if (!params.src || !params.src.startsWith(this.BASE64_HEADER_START)) params.src = this.BASE64_NOT_FOUND;

    this._canvasImage = new Image();

    this._canvasImage.onload = () => {
      this._ref.image(this._canvasImage);
      if (this._ref.height() <= this.EPSILON) this._ref.height(this._canvasImage.height);
      if (this._ref.width() <= this.EPSILON) this._ref.width(this._canvasImage.width);

      this._ratio =
        this._ref.height() <= this.EPSILON || this._ref.width() <= this.EPSILON
          ? 1
          : this._ref.height() / this._ref.width();

      // need to rescale only if input width and height are 0 - we do not loading Viewpoint with existing params
      if (
        (params.width <= this.EPSILON || params.height <= this.EPSILON) &&
        (params.maxWidth >= this.EPSILON || params.maxWidth >= this.EPSILON)
      ) {
        const heightOutOfCanvas = params.maxHeight - this._canvasImage.height;
        const widthOutOfCanvas = params.maxWidth - this._canvasImage.width;

        if (heightOutOfCanvas <= this.EPSILON || widthOutOfCanvas <= this.EPSILON) {
          if (widthOutOfCanvas <= this.EPSILON && widthOutOfCanvas < heightOutOfCanvas / this._ratio) {
            this._ref.height(params.maxWidth * this._ratio);
            this._ref.width(params.maxWidth);
          } else {
            this._ref.width(params.maxHeight / this._ratio);
            this._ref.height(params.maxHeight);
          }
        }
      }
    };

    this._canvasImage.onerror = () => {
      this._canvasImage.onerror = function () {};
      this._canvasImage.src = this.BASE64_NOT_FOUND;
    };

    this._canvasImage.src = params.src;

    this._ref = new Konva.Image({
      x: params.position.x,
      y: params.position.y,
      image: this._canvasImage,
      width: params.width ?? 0,
      height: params.height ?? 0,
      draggable: true,
    });

    this._ref.on("transform", (e) => {
      const attrs = e.target.attrs;

      if (attrs.rotation !== this._ref.rotation()) this._ref.rotation(attrs.rotation);

      const scaleByX = Math.abs(attrs.scaleX - 1) > 10e-6;
      const scaleByY = Math.abs(attrs.scaleY - 1) > 10e-6;

      let newWidth = this._ref.width();
      if (scaleByX) newWidth *= attrs.scaleX;
      let newHeight = this._ref.height();
      if (scaleByY) newHeight *= attrs.scaleY;

      if (e.evt.ctrlKey || e.evt.shiftKey) {
        if (scaleByX) {
          this._ref.width(newWidth);
          this._ref.height(newWidth * this._ratio);
        } else {
          this._ref.width(newHeight / this._ratio);
          this._ref.height(newHeight);
        }
      } else {
        if (scaleByX) {
          this._ref.width(newWidth);
        }
        if (scaleByY) {
          this._ref.height(newHeight);
        }
      }

      this._ref.scale({ x: 1, y: 1 });
    });

    this._ref.id(this._ref._id.toString());
  }

  getSrc(): string {
    return this._canvasImage.src;
  }

  setSrc(src: any) {
    this._canvasImage.src = src;
  }

  getWidth(): number {
    return this._ref.width();
  }

  setWidth(w: number): void {
    this._ref.width(w);
    this._ref.height(w * this._ratio);
  }

  getHeight(): number {
    return this._ref.height();
  }

  setHeight(h: number): void {
    this._ref.height(h);
    this._ref.width(h / this._ratio);
  }

  ref() {
    return this._ref;
  }

  id(): string {
    return this._ref.id();
  }

  enableMouseEditing(value: boolean): void {
    this._ref.draggable(value);
  }

  type(): string {
    return "Image";
  }

  getRotation(): number {
    return this._ref.rotation();
  }

  setRotation(degrees: number): void {
    this._ref.rotation(degrees);
  }

  getZIndex(): number {
    return this._ref.zIndex();
  }

  setZIndex(zIndex: number): void {
    this._ref.zIndex(zIndex);
  }

  delete() {
    this._ref.destroy();
    this._ref = null;
  }

  getPosition(): { x: number; y: number } {
    return this._ref.getPosition();
  }

  setPosition(x: number, y: number): void {
    this._ref.setPosition({ x, y });
  }
}