using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public enum Area
{
    LeftWall,
    RightWall,
    TopWall,
    Floor
}

public class FrozenScreenToWorldSpace : MonoBehaviour {

    public static FrozenScreenToWorldSpace Instance {
        get {
            /*
            if (instacnce == null && GameObject.Find("FrozenScreenToWorldSpace").GetComponent<FrozenScreenToWorldSpace>() != null)
                instacnce = GameObject.Find("FrozenScreenToWorldSpace").GetComponent<FrozenScreenToWorldSpace>();
            else
                instacnce = new GameObject("FrozenScreenToWorldSpace").AddComponent<FrozenScreenToWorldSpace>();
                */
                return instacnce;
        }
    }
    private static FrozenScreenToWorldSpace instacnce;

    public float width = 8;
    public float length = 5;
    public float height = 3;
    public float blackLength = 0.89f;
    public float PixelsByMeter = 360;
    public float finalPixelsByMeter = 90;
    [System.Serializable]
    public class RenderTextureROI
    {
        public float X;
        public float Y;
        public float ROI_X;
        public float ROI_Y;
        public RenderTextureROI(float x, float y, float roi_x, float roi_y)
        {
            X = x;
            Y = y;
            ROI_X = roi_x;
            ROI_Y = roi_y;
        }
        public RenderTextureROI() { }
    }

    [SerializeField]
    RenderTextureROI LeftWall = new RenderTextureROI();
    [SerializeField]
    RenderTextureROI TopWall = new RenderTextureROI();
    [SerializeField]
    RenderTextureROI RightWall = new RenderTextureROI();
    [SerializeField]
    RenderTextureROI Floor = new RenderTextureROI();

    Dictionary<Area, RenderTextureROI> RenderTextureROIList = new Dictionary<Area, RenderTextureROI>();

    Dictionary<Area, Plane> wallPlaneList = new Dictionary<Area, Plane>();

    private float totalLength;
    private float totalWidth;

    private void Awake()
    {
        instacnce = this;
        InitailROISetting();
    }

    void InitailROISetting()
    {
        totalLength = height * 2 + width;
        totalWidth = height + length + blackLength;
        LeftWall = new RenderTextureROI(0, height / totalWidth, height / totalLength, length / totalWidth);
        RightWall = new RenderTextureROI((height + width) / totalLength, height / totalWidth, height / totalLength, length / totalWidth);
        TopWall = new RenderTextureROI((height) / totalLength, 0, width / totalLength, height / totalWidth);
        Floor = new RenderTextureROI(height / totalLength, height / totalWidth, width / totalLength, length / totalWidth);
        RenderTextureROIList.Add(Area.LeftWall, LeftWall);
        RenderTextureROIList.Add(Area.RightWall, RightWall);
        RenderTextureROIList.Add(Area.TopWall, TopWall);
        RenderTextureROIList.Add(Area.Floor, Floor);
        wallPlaneList.Add(Area.LeftWall, new Plane(Vector3.right, new Vector3(-width * 0.5f, 0, 0)));
        wallPlaneList.Add(Area.RightWall, new Plane(Vector3.left, new Vector3(width * 0.5f, 0, 0)));
        wallPlaneList.Add(Area.TopWall, new Plane(Vector3.back, new Vector3(0, 0, length * 0.5f)));
    }

    public RenderTextureROI GetROI(Area area)
    {
        if (RenderTextureROIList.ContainsKey(area))
            return RenderTextureROIList[area];
        return null;
    }

    public Plane GetWallPlane(Area area)
    {
        if (wallPlaneList.ContainsKey(area))
            return wallPlaneList[area];
        return new Plane();
    }

    public Vector2 GetFinalScreenPos(Area area, Vector2 wallROI)
    {
        if(!RenderTextureROIList.ContainsKey(area))
            return Vector2.zero;
        RenderTextureROI textureROI = GetROI(area);
        Vector2 currenPos = Vector2.zero;
        if (area == Area.LeftWall)
        {
            float x = textureROI.X + (1 - wallROI.y) * textureROI.ROI_X;
            float y = textureROI.Y + (1 - wallROI.x) * textureROI.ROI_Y;
            currenPos = new Vector2(x, y);
        }
        if (area == Area.RightWall)
        {
            float x = textureROI.X + wallROI.y * textureROI.ROI_X;
            float y = textureROI.Y + (1 - wallROI.x) * textureROI.ROI_Y;
            currenPos = new Vector2(x, y);
        }
        if (area == Area.TopWall)
        {
            float x = textureROI.X + wallROI.x * textureROI.ROI_X;
            float y = textureROI.Y + (1 - wallROI.y) * textureROI.ROI_Y;
            currenPos = new Vector2(x, y);
        }
        currenPos = new Vector2(currenPos.x * Screen.width, ( 1 - currenPos.y) * Screen.height);
        return currenPos;
    }

    public Vector2 GetWallRoiFromPosition(Area area, Vector3 position)
    {
        position -= transform.position;
        Vector2 roi = Vector2.zero;
        switch (area)
        {            
            case Area.TopWall:
                {
                    roi.x = (position.x + width * 0.5f) / width;
                    roi.y = position.y / height;
                }
                break;
            case Area.LeftWall:
                {
                    roi.x = (position.z + length * 0.5f) / length;
                    roi.y = position.y / height;
                }
                break;
            case Area.RightWall:
                {
                    roi.x = (position.z + length * 0.5f) / length;
                    roi.y = position.y / height;
                }
                break;
        }
        return roi;
    }

    public Vector3 Position { get { return transform.position; } }
}