// (c) Copyright HutongGames, LLC 2010-2013. All rights reserved.

using UnityEngine;

namespace HutongGames.PlayMaker.Actions
{
    // TODO: fairly basic right now
    // should have more options and be more robust, e.g., other fingers.

    [ActionCategory(ActionCategory.Device)]
    [Tooltip("Sends an event when a swipe is detected.")]
    public class SwipeGestureEvent : FsmStateAction
    {
        [Tooltip("How far a touch has to travel to be considered a swipe. Uses normalized distance (e.g. 1 = 1 screen diagonal distance). Should generally be a very small number.")]
        public FsmFloat minSwipeDistance;

        [Tooltip("Event to send when swipe left detected.")]
        public FsmEvent swipeLeftEvent;
        [Tooltip("Event to send when swipe right detected.")]
        public FsmEvent swipeRightEvent;
        [Tooltip("Event to send when swipe up detected.")]
        public FsmEvent swipeUpEvent;
        [Tooltip("Event to send when swipe down detected.")]
        public FsmEvent swipeDownEvent;

        // TODO
/*      [UIHint(UIHint.Variable)]
        [Tooltip("Store the speed of the swipe.")]
        public FsmFloat getSpeed;
        [UIHint(UIHint.Variable)]
        [Tooltip("Store the distance the swipe traveled.")]
        public FsmFloat getDistance;*/

        float screenDiagonalSize;
        float minSwipeDistancePixels;
        bool touchStarted;
        Vector2 touchStartPos;
        //float touchStartTime;

        public override void Reset()
        {
            minSwipeDistance = 0.1f;
            swipeLeftEvent = null;
            swipeRightEvent = null;
            swipeUpEvent = null;
            swipeDownEvent = null;
        }

        public override void OnEnter()
        {
            screenDiagonalSize = Mathf.Sqrt(Screen.width * Screen.width + Screen.height * Screen.height);
            minSwipeDistancePixels = minSwipeDistance.Value * screenDiagonalSize;
        }

        public override void OnUpdate()
        {
            if (Input.touchCount > 0)
            {
                var touch = Input.touches[0];

                switch (touch.phase)
                {
                case TouchPhase.Began:

                    touchStarted = true;
                    touchStartPos = touch.position;
                    //touchStartTime = FsmTime.RealtimeSinceStartup;

                    break;

                case TouchPhase.Moved:

                    if(touchStarted)
                        TestForSwipeGesture(touch);

                    break;

                case TouchPhase.Ended:

                    touchStarted = false;
                    break;
                }
            }
        }

        void TestForSwipeGesture(Touch touch)
        {
            // test min distance

            var lastPos = touch.position;
            var distance = Vector2.Distance(lastPos, touchStartPos);

            if (distance > minSwipeDistancePixels)
            {
                float dy = lastPos.y - touchStartPos.y;
                float dx = lastPos.x - touchStartPos.x;

                float angle = Mathf.Rad2Deg * Mathf.Atan2(dx, dy);

                angle = (360 + angle - 45) % 360;

                Debug.Log (angle);

                if (angle < 90)
                {
                    Fsm.Event(swipeRightEvent);
                }
                else if (angle < 180)
                {
                    Fsm.Event(swipeDownEvent);
                }
                else if (angle < 270)
                {
                    Fsm.Event(swipeLeftEvent);
                }
                else
                {
                    Fsm.Event(swipeUpEvent);
                }

                touchStarted = false;
            }
        }

    }
}