import {MathConsts}				from "awayjs-core/lib/geom/MathConsts";

import {ControllerBase}			from "../controllers/ControllerBase";
import {DisplayObject}			from "../display/DisplayObject";

/**
 * Extended camera used to hover round a specified target object.
 *
 * @see    away3d.containers.View3D
 */
export class FirstPersonController extends ControllerBase
{
	public _iCurrentPanAngle:number = 0;
	public  _iCurrentTiltAngle:number = 90;

	private _panAngle:number = 0;
	private _tiltAngle:number = 90;
	private _minTiltAngle:number = -90;
	private _maxTiltAngle:number = 90;
	private _steps:number = 8;
	private _walkIncrement:number = 0;
	private _strafeIncrement:number = 0;
	private _wrapPanAngle:boolean = false;

	public fly:boolean = false;

	/**
	 * Fractional step taken each time the <code>hover()</code> method is called. Defaults to 8.
	 *
	 * Affects the speed at which the <code>tiltAngle</code> and <code>panAngle</code> resolve to their targets.
	 *
	 * @see    #tiltAngle
	 * @see    #panAngle
	 */
	public get steps():number
	{
		return this._steps;
	}

	public set steps(val:number)
	{
		val = (val < 1)? 1 : val;

		if (this._steps == val)
			return;

		this._steps = val;

		this.pNotifyUpdate();
	}

	/**
	 * Rotation of the camera in degrees around the y axis. Defaults to 0.
	 */
	public get panAngle():number
	{
		return this._panAngle;
	}

	public set panAngle(val:number)
	{
		if (this._panAngle == val)
			return;

		this._panAngle = val;

		this.pNotifyUpdate();
	}

	/**
	 * Elevation angle of the camera in degrees. Defaults to 90.
	 */
	public get tiltAngle():number
	{
		return this._tiltAngle;
	}

	public set tiltAngle(val:number)
	{
		val = Math.max(this._minTiltAngle, Math.min(this._maxTiltAngle, val));

		if (this._tiltAngle == val)
			return;

		this._tiltAngle = val;

		this.pNotifyUpdate();
	}

	/**
	 * Minimum bounds for the <code>tiltAngle</code>. Defaults to -90.
	 *
	 * @see    #tiltAngle
	 */
	public get minTiltAngle():number
	{
		return this._minTiltAngle;
	}

	public set minTiltAngle(val:number)
	{
		if (this._minTiltAngle == val)
			return;

		this._minTiltAngle = val;

		this.tiltAngle = Math.max(this._minTiltAngle, Math.min(this._maxTiltAngle, this._tiltAngle));
	}

	/**
	 * Maximum bounds for the <code>tiltAngle</code>. Defaults to 90.
	 *
	 * @see    #tiltAngle
	 */
	public get maxTiltAngle():number
	{
		return this._maxTiltAngle;
	}

	public set maxTiltAngle(val:number)
	{
		if (this._maxTiltAngle == val)
			return;

		this._maxTiltAngle = val;

		this.tiltAngle = Math.max(this._minTiltAngle, Math.min(this._maxTiltAngle, this._tiltAngle));
	}


	/**
	 * Defines whether the value of the pan angle wraps when over 360 degrees or under 0 degrees. Defaults to false.
	 */
	public get wrapPanAngle():boolean
	{
		return this._wrapPanAngle;
	}

	public set wrapPanAngle(val:boolean)
	{
		if (this._wrapPanAngle == val)
			return;

		this._wrapPanAngle = val;

		this.pNotifyUpdate();
	}

	/**
	 * Creates a new <code>HoverController</code> object.
	 */
	constructor(targetObject:DisplayObject = null, panAngle:number = 0, tiltAngle:number = 90, minTiltAngle:number = -90, maxTiltAngle:number = 90, steps:number = 8, wrapPanAngle:boolean = false)
	{
		super(targetObject);

		this.panAngle = panAngle;
		this.tiltAngle = tiltAngle;
		this.minTiltAngle = minTiltAngle;
		this.maxTiltAngle = maxTiltAngle;
		this.steps = steps;
		this.wrapPanAngle = wrapPanAngle;

		//values passed in contrustor are applied immediately
		this._iCurrentPanAngle = this._panAngle;
		this._iCurrentTiltAngle = this._tiltAngle;
	}

	/**
	 * Updates the current tilt angle and pan angle values.
	 *
	 * Values are calculated using the defined <code>tiltAngle</code>, <code>panAngle</code> and <code>steps</code> variables.
	 *
	 * @param interpolate   If the update to a target pan- or tiltAngle is interpolated. Default is true.
	 *
	 * @see    #tiltAngle
	 * @see    #panAngle
	 * @see    #steps
	 */
	public update(interpolate:boolean = true):void
	{
		if (this._tiltAngle != this._iCurrentTiltAngle || this._panAngle != this._iCurrentPanAngle) {

			this._pControllerDirty = true;

			if (this._wrapPanAngle) {
				if (this._panAngle < 0) {
					this._iCurrentPanAngle += this._panAngle%360 + 360 - this._panAngle;
					this._panAngle = this._panAngle%360 + 360;
				} else {
					this._iCurrentPanAngle += this._panAngle%360 - this._panAngle;
					this._panAngle = this._panAngle%360;
				}

				while (this._panAngle - this._iCurrentPanAngle < -180)
					this._iCurrentPanAngle -= 360;

				while (this._panAngle - this._iCurrentPanAngle > 180)
					this._iCurrentPanAngle += 360;
			}

			if (interpolate) {
				this._iCurrentTiltAngle += (this._tiltAngle - this._iCurrentTiltAngle)/(this.steps + 1);
				this._iCurrentPanAngle += (this._panAngle - this._iCurrentPanAngle)/(this.steps + 1);
			} else {
				this._iCurrentTiltAngle = this._tiltAngle;
				this._iCurrentPanAngle = this._panAngle;
			}

			//snap coords if angle differences are close
			if ((Math.abs(this.tiltAngle - this._iCurrentTiltAngle) < 0.01) && (Math.abs(this._panAngle - this._iCurrentPanAngle) < 0.01)) {
				this._iCurrentTiltAngle = this._tiltAngle;
				this._iCurrentPanAngle = this._panAngle;
			}
		}

		this.targetObject.rotationX = this._iCurrentTiltAngle;
		this.targetObject.rotationY = this._iCurrentPanAngle;

		if (this._walkIncrement) {
			if (this.fly) {
				this.targetObject.transform.moveForward(this._walkIncrement);
			} else {
				this.targetObject.x += this._walkIncrement*Math.sin(this._panAngle*MathConsts.DEGREES_TO_RADIANS);
				this.targetObject.z += this._walkIncrement*Math.cos(this._panAngle*MathConsts.DEGREES_TO_RADIANS);
			}
			this._walkIncrement = 0;
		}

		if (this._strafeIncrement) {
			this.targetObject.transform.moveRight(this._strafeIncrement);
			this._strafeIncrement = 0;
		}

	}

	public incrementWalk(val:number):void
	{
		if (val == 0)
			return;

		this._walkIncrement += val;

		this.pNotifyUpdate();
	}

	public incrementStrafe(val:number):void
	{
		if (val == 0)
			return;

		this._strafeIncrement += val;

		this.pNotifyUpdate();
	}

}