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

namespace bbiwarg.Recognition.FingerRecognition
{
    class FingerSlice
    {
        private LineSegment2D lineSegment;
        private bool lineSegmentUpToDate;

        public Vector2D Mid { get; private set; }
        public Vector2D Start { get; private set; }
        public Vector2D StartOuter { get; private set; }
        public Vector2D End { get; private set; }
        public Vector2D EndOuter { get; private set; }
        public LineSegment2D LineSegment { get { if (!lineSegmentUpToDate) updateLineSegment(); return lineSegment; } }
        public Vector2D Direction { get { return LineSegment.Direction; } }
        public float Length { get { return LineSegment.Length; } }

        public FingerSlice(Vector2D start, Vector2D end)
        {
            Start = start;
            End = end;
            Mid = (start + end) / 2;
            updateLineSegment();
            StartOuter = (Start + Constants.FingerSliceOutMargin * Direction.getInverse()).moveInBound(Vector2D.Zero, Constants.MaxPixel, Direction);
            EndOuter = (End + Constants.FingerSliceOutMargin * Direction).moveInBound(Vector2D.Zero, Constants.MaxPixel, Direction.getInverse());
        }

        private void updateLineSegment()
        {
            lineSegment = new LineSegment2D(Start, End);
            lineSegmentUpToDate = true;
        }

    }
}