text: /**
   * The Base class for all Nodes.
   */
  class NodeBase {
    /**
     * @param {Object} options
     * @param {Object} body
     * @param {Label} labelModule
     */
    constructor(options, body, labelModule) {
      this.body = body;
      this.labelModule = labelModule;
      this.setOptions(options);
      this.top = undefined;
      this.left = undefined;
      this.height = undefined;
      this.width = undefined;
      this.radius = undefined;
      this.margin = undefined;
      this.refreshNeeded = true;
      this.boundingBox = {top: 0, left: 0, right: 0, bottom: 0};
    }
  
    /**
     *
     * @param {Object} options
     */
    setOptions(options) {
      this.options = options;
    }
  
    /**
     *
     * @param {Label} labelModule
     * @private
     */
    _setMargins(labelModule) {
      this.margin = {};
      if (this.options.margin) {
        if (typeof this.options.margin == 'object') {
          this.margin.top = this.options.margin.top;
          this.margin.right = this.options.margin.right;
          this.margin.bottom = this.options.margin.bottom;
          this.margin.left = this.options.margin.left;
        } else {
          this.margin.top = this.options.margin;
          this.margin.right = this.options.margin;
          this.margin.bottom = this.options.margin;
          this.margin.left = this.options.margin;
        }
      }
      labelModule.adjustSizes(this.margin)
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {number} angle
     * @returns {number}
     * @private
     */
    _distanceToBorder(ctx,angle) {
      var borderWidth = this.options.borderWidth;
      this.resize(ctx);
      return Math.min(
          Math.abs(this.width / 2 / Math.cos(angle)),
          Math.abs(this.height / 2 / Math.sin(angle))) + borderWidth;
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    enableShadow(ctx, values) {
      if (values.shadow) {
        ctx.shadowColor = values.shadowColor;
        ctx.shadowBlur = values.shadowSize;
        ctx.shadowOffsetX = values.shadowX;
        ctx.shadowOffsetY = values.shadowY;
      }
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    disableShadow(ctx, values) {
      if (values.shadow) {
        ctx.shadowColor = 'rgba(0,0,0,0)';
        ctx.shadowBlur = 0;
        ctx.shadowOffsetX = 0;
        ctx.shadowOffsetY = 0;
      }
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    enableBorderDashes(ctx, values) {
      if (values.borderDashes !== false) {
        if (ctx.setLineDash !== undefined) {
          let dashes = values.borderDashes;
          if (dashes === true) {
            dashes = [5,15]
          }
          ctx.setLineDash(dashes);
        }
        else {
          console.warn("setLineDash is not supported in this browser. The dashed borders cannot be used.");
          this.options.shapeProperties.borderDashes = false;
          values.borderDashes = false;
        }
      }
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    disableBorderDashes(ctx, values) {
      if (values.borderDashes !== false) {
        if (ctx.setLineDash !== undefined) {
          ctx.setLineDash([0]);
        }
        else {
          console.warn("setLineDash is not supported in this browser. The dashed borders cannot be used.");
          this.options.shapeProperties.borderDashes = false;
          values.borderDashes = false;
        }
      }
    }
  
    /**
     * Determine if the shape of a node needs to be recalculated.
     *
     * @param {boolean} selected
     * @param {boolean} hover
     * @returns {boolean}
     * @protected
     */
    needsRefresh(selected, hover) {
      if (this.refreshNeeded === true) {
        // This is probably not the best location to reset this member.
        // However, in the current logic, it is the most convenient one.
        this.refreshNeeded = false;
        return true;
      }
  
      return  (this.width === undefined) || (this.labelModule.differentState(selected, hover));
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    initContextForDraw(ctx, values) {
      var borderWidth = values.borderWidth / this.body.view.scale;
  
      ctx.lineWidth = Math.min(this.width, borderWidth);
      ctx.strokeStyle = values.borderColor;
      ctx.fillStyle = values.color;
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    performStroke(ctx, values) {
      var borderWidth = values.borderWidth / this.body.view.scale;
  
      //draw dashed border if enabled, save and restore is required for firefox not to crash on unix.
      ctx.save();
      // if borders are zero width, they will be drawn with width 1 by default. This prevents that
      if (borderWidth > 0) {
        this.enableBorderDashes(ctx, values);
        //draw the border
        ctx.stroke();
        //disable dashed border for other elements
        this.disableBorderDashes(ctx, values);
      }
      ctx.restore();
    }
  
    /**
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {{toArrow: boolean, toArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), toArrowType: *, middleArrow: boolean, middleArrowScale: (number|allOptions.edges.arrows.middle.scaleFactor|{number}|Array), middleArrowType: (allOptions.edges.arrows.middle.type|{string}|string|*), fromArrow: boolean, fromArrowScale: (allOptions.edges.arrows.to.scaleFactor|{number}|allOptions.edges.arrows.middle.scaleFactor|allOptions.edges.arrows.from.scaleFactor|Array|number), fromArrowType: *, arrowStrikethrough: (*|boolean|allOptions.edges.arrowStrikethrough|{boolean}), color: undefined, inheritsColor: (string|string|string|allOptions.edges.color.inherit|{string, boolean}|Array|*), opacity: *, hidden: *, length: *, shadow: *, shadowColor: *, shadowSize: *, shadowX: *, shadowY: *, dashes: (*|boolean|Array|allOptions.edges.dashes|{boolean, array}), width: *}} values
     */
    performFill(ctx, values) {
      // draw shadow if enabled
      this.enableShadow(ctx, values);
      // draw the background
      ctx.fill();
      // disable shadows for other elements.
      this.disableShadow(ctx, values);
  
      this.performStroke(ctx, values);
    }
  
  
    /**
     *
     * @param {number} margin
     * @private
     */
    _addBoundingBoxMargin(margin) {
      this.boundingBox.left   -= margin;
      this.boundingBox.top    -= margin;
      this.boundingBox.bottom += margin;
      this.boundingBox.right  += margin;
    }
  
  
    /**
     * Actual implementation of this method call.
     *
     * Doing it like this makes it easier to override
     * in the child classes.
     *
     * @param {number} x width
     * @param {number} y height
     * @param {CanvasRenderingContext2D} ctx
     * @param {boolean} selected
     * @param {boolean} hover
     * @private
     */
    _updateBoundingBox(x, y, ctx, selected, hover) {
      if (ctx !== undefined) {
        this.resize(ctx, selected, hover);
      }
  
      this.left = x - this.width / 2;
      this.top  = y - this.height/ 2;
  
      this.boundingBox.left   = this.left;
      this.boundingBox.top    = this.top;
      this.boundingBox.bottom = this.top + this.height;
      this.boundingBox.right  = this.left + this.width;
    }
  
  
    /**
     * Default implementation of this method call.
     * This acts as a stub which can be overridden.
     *
     * @param {number} x width
     * @param {number} y height
     * @param {CanvasRenderingContext2D} ctx
     * @param {boolean} selected
     * @param {boolean} hover
     */
    updateBoundingBox(x, y, ctx, selected, hover) {
      this._updateBoundingBox(x, y, ctx, selected, hover);
    }
  
  
    /**
     * Determine the dimensions to use for nodes with an internal label
     *
     * Currently, these are: Circle, Ellipse, Database, Box
     * The other nodes have external labels, and will not call this method
     *
     * If there is no label, decent default values are supplied.
     *
     * @param {CanvasRenderingContext2D} ctx
     * @param {boolean} [selected]
     * @param {boolean} [hover]
     * @returns {{width:number, height:number}}
     */
    getDimensionsFromLabel(ctx, selected, hover) {
      // NOTE: previously 'textSize' was not put in 'this' for Ellipse
      // TODO: examine the consequences.
      this.textSize = this.labelModule.getTextSize(ctx, selected, hover);
      var width  = this.textSize.width;
      var height = this.textSize.height;
  
      const DEFAULT_SIZE = 14;
      if (width === 0) {
        // This happens when there is no label text set
        width = DEFAULT_SIZE;  // use a decent default
        height = DEFAULT_SIZE; // if width zero, then height also always zero
      }
  
      return {width:width, height:height};
    }
  }
  
  export default NodeBase;
  