/******************************************************************************
 * Spine Runtimes License Agreement
 * Last updated January 1, 2020. Replaces all prior versions.
 *
 * Copyright (c) 2013-2020, Esoteric Software LLC
 *
 * Integration of the Spine Runtimes into software or otherwise creating
 * derivative works of the Spine Runtimes is permitted under the terms and
 * conditions of Section 2 of the Spine Editor License Agreement:
 * http://esotericsoftware.com/spine-editor-license
 *
 * Otherwise, it is permitted to integrate the Spine Runtimes into software
 * or otherwise create derivative works of the Spine Runtimes (collectively,
 * "Products"), provided that each user of the Products must obtain their own
 * Spine Editor license and redistribution of the Products in any form must
 * include this license and copyright notice.
 *
 * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES,
 * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

module spine.webgl {
	export class OrthoCamera {
		position = new Vector3(0, 0, 0);
		direction = new Vector3(0, 0, -1);
		up = new Vector3(0, 1, 0);
		near = 0;
		far = 100;
		zoom = 1;
		viewportWidth = 0;
		viewportHeight = 0;
		projectionView = new Matrix4();
		inverseProjectionView = new Matrix4();
		projection = new Matrix4();
		view = new Matrix4();

		private tmp = new Vector3();

		constructor (viewportWidth: number, viewportHeight: number) {
			this.viewportWidth = viewportWidth;
			this.viewportHeight = viewportHeight;
			this.update();
		}

		update () {
			let projection = this.projection;
			let view = this.view;
			let projectionView = this.projectionView;
			let inverseProjectionView = this.inverseProjectionView;
			let zoom = this.zoom, viewportWidth = this.viewportWidth, viewportHeight = this.viewportHeight;
			projection.ortho(zoom * (-viewportWidth / 2), zoom * (viewportWidth / 2),
							 zoom * (-viewportHeight / 2), zoom * (viewportHeight / 2),
							 this.near, this.far);
			view.lookAt(this.position, this.direction, this.up);
			projectionView.set(projection.values);
			projectionView.multiply(view);
			inverseProjectionView.set(projectionView.values).invert();
		}

		screenToWorld (screenCoords: Vector3, screenWidth: number, screenHeight: number) {
			let x = screenCoords.x, y = screenHeight - screenCoords.y - 1;
			let tmp = this.tmp;
			tmp.x = (2 * x) / screenWidth - 1;
			tmp.y = (2 * y) / screenHeight - 1;
			tmp.z = (2 * screenCoords.z) - 1;
			tmp.project(this.inverseProjectionView);
			screenCoords.set(tmp.x, tmp.y, tmp.z);
			return screenCoords;
		}

		setViewport(viewportWidth: number, viewportHeight: number) {
			this.viewportWidth = viewportWidth;
			this.viewportHeight = viewportHeight;
		}
	}
}
