using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using bbiwarg.Images;

namespace bbiwarg.Detectors.Fingers
{
    class FingerTracker
    {
        private FingerImage fingerImage;
        private List<Finger>[] detectedFingers;
        private List<Finger> trackedFingers;
        private int framesUntilTracked;

        public FingerTracker() {
            framesUntilTracked = 5;
            detectedFingers = new List<Finger>[framesUntilTracked];

            for (int i = 0; i < framesUntilTracked; i++)
            {
                detectedFingers[i] = new List<Finger>();
            }
        }

        public List<Finger> getFingers() {
            return trackedFingers;
        }

        public void setDetectedTouchEventsThisFrame(List<Finger> detectedFingersThisFrame, FingerImage fingerImage)
        {
            this.fingerImage = fingerImage;

            for (int i = (framesUntilTracked - 1); i > 0; i--)
            {
                detectedFingers[i] = detectedFingers[i - 1];
            }
            detectedFingers[0] = detectedFingersThisFrame;


            findTrackedFingers();
        }

        private void findTrackedFingers()
        {
            trackedFingers = new List<Finger>();

            foreach (Finger finger in detectedFingers[0])
            {
                bool tracked = true;
                for (int i = 1; i < framesUntilTracked; i++)
                {
                    if (!hasSimilarFingerInFrame(finger, i)) tracked = false;
                }
                if (tracked)
                {
                    fingerImage.drawLine(finger.getLineEndPoint1(), finger.getLineEndPoint2(), FingerImageState.fingerTracked);
                    trackedFingers.Add(finger);
                }
            }
        }

        private bool hasSimilarFingerInFrame(Finger finger, int frame) {
            foreach (Finger f in detectedFingers[frame])
            {
                if (finger.isSimilarTo(f))
                    return true;
            }

            return false;
        }
    }
}