library-ts/browser/dom/DOMHitTest.ts

import { Box2 } from "../geometry/Box2";
import { Vector2 } from "../geometry/Vector2";

export class DOMHitTest
{
  static get scrollOffset():Vector2
  { 
    return new Vector2( window.scrollX, window.scrollY );
  }
   
  static getPageRect( e:Element ):ClientRect
  {
    let pageBox = this.getPageBox( e );

    return Box2.toDomRect( pageBox );
  }

  static other()
  {
    return true;
  }

  static isPointerOver( me:MouseEvent|TouchEvent, e:Element )
  {
    if ( ! me || ! e )
    {
      return false;
    }

    let relative = DOMHitTest.getNormalizedPointerPosition( me, e );
    
    if ( relative.x < 0 || relative.x > 1)
    {
      return false;
    }

    if ( relative.y < 0 || relative.y > 1 )
    {
      return false;
    }
    
    return true;
  } 

  static getPageBox( e:Element ):Box2
  {
    let pageBox = Box2.fromClientRect( e.getBoundingClientRect() );

    pageBox.translate( this.scrollOffset );
 
    return pageBox;
  }

  private static _lastPageX:number = null;
  private static _lastPageY:number = null;

  static getPointerPosition( e:MouseEvent|TouchEvent ):Vector2
  {
    let isMouseEvent = /mouse|click/.test( e.type ); 
    console.log( e.type );
    let mouseEvent = isMouseEvent ? e as MouseEvent : null;
    let touchEvent = isMouseEvent ? null : ( e as TouchEvent );
    let pageX = isMouseEvent ? mouseEvent.pageX : touchEvent.touches.length === 0 ? null : touchEvent.touches[ 0 ].pageX;
    let pageY = isMouseEvent ? mouseEvent.pageY : touchEvent.touches.length === 0 ? null : touchEvent.touches[ 0 ].pageY;

    // if ( isMouseEvent && CustomMouse.active )
    // {
    //   pageX = CustomMouse.x;
    //   pageY = CustomMouse.y;
    // }

    if ( pageX === null )
    {
      pageX = DOMHitTest._lastPageX === undefined ? window.innerWidth / 2 : DOMHitTest._lastPageX;
    }

    if ( pageY === null )
    {
      pageY = DOMHitTest._lastPageY === undefined ? window.innerHeight / 2 : DOMHitTest._lastPageY;
    }

    DOMHitTest._lastPageX = pageX;
    DOMHitTest._lastPageY = pageY;
    
    return new Vector2( pageX, pageY );
  }

  static getRelativePointerPosition( e:MouseEvent|TouchEvent, element:Element )
  {
    let position = this.getPointerPosition( e );
    let pageRect = this.getPageBox( element ); 

    return position.sub( pageRect.min );
  }

  static getRelativeWindowPosition( e:MouseEvent|TouchEvent )
  {
    let position = this.getPointerPosition( e );
    let windowBox = Box2.create( new Vector2( 0, 0 ), new Vector2( window.innerWidth, window.innerHeight ) );

    position.sub( windowBox.min );
    let size = windowBox.size;
    position.x /= size.x;
    position.y /= size.y;
    
    return position;

  }

  static getNormalizedPointerPosition( e:MouseEvent|TouchEvent, element:Element )
  {
    let position = this.getPointerPosition( e );
    let pageRect = this.getPageBox( element );

    position.sub( pageRect.min );
    let size = pageRect.size;
    position.x /= size.x;
    position.y /= size.y;

    return position;

  }

  static getNormalizedPosition( position:Vector2, element:Element )
  {
    let pageRect = this.getPageBox( element );

    position.sub( pageRect.min );
    let size = pageRect.size;
    position.x /= size.x;
    position.y /= size.y;

    return position;

  }


}