using UnityEngine;

public class Movement : MonoBehaviour {

    public Transform[] Whites;
    public Transform[] Blacks;

    public Vector3[] whitesPos;
    public Vector3[] blacksPos;

    public Vector3[] whitesDeadPos;
    public Transform[] whitesDead;

    public Vector3[] blacksDeadPos;
    public Transform[] blacksDead;

    public Transform[] startingBlocksWhite;
    public Transform[] startingBlocksBlack;

    public Transform grabbedPawn;
    public GameObject placeBlock;

    Ray ray;
    RaycastHit hit;

    public void Start()
    {
        for(int i = 0; i < 16; i++)
        {
            Whites[i].transform.position = startingBlocksWhite[i].transform.position;
            Blacks[i].transform.position = startingBlocksBlack[i].transform.position;

        }
        SavePos();

        for(int g = 0; g < 16; g++)
        {
            Whites[g].transform.position = whitesPos[g];
            Blacks[g].transform.position = blacksPos[g];
        }
        SavePos();

        for(int h = 0; h < 15; h++)
        {
            whitesDeadPos[h] = whitesDead[h].transform.position;
            blacksDeadPos[h] = blacksDead[h].transform.position;
        }
    }

    public void Update()
    {
        ray = Camera.main.ScreenPointToRay(Input.mousePosition);

        if (Physics.Raycast(ray, out hit))
        {
            if (Input.GetMouseButton(0))
            {
                if (hit.transform.tag == "Chess")
                {
                    grabbedPawn = hit.transform;
                    grabbedPawn.gameObject.layer = 8;
                    for (int i = 0; i < 16; i++)
                    {
                        Whites[i].GetComponent<BoxCollider>().enabled = false;
                        Blacks[i].GetComponent<BoxCollider>().enabled = false;
                    }
                } else if (hit.transform.tag == "Chess Black")
                {
                    grabbedPawn = hit.transform;
                    grabbedPawn.gameObject.layer = 9;
                    for (int i = 0; i < 16; i++)
                    {
                        Whites[i].GetComponent<BoxCollider>().enabled = false;
                        Blacks[i].GetComponent<BoxCollider>().enabled = false;
                    }
                }
            }
            else if (Input.GetMouseButtonUp(0))
            {
                if (hit.transform.tag != "Random")
                {
                    placeBlock = GameObject.Find(hit.transform.name);

                    if (placeBlock != null)
                    {
                        if (grabbedPawn != null)
                        {
                            Vector3 blockPos = new Vector3(placeBlock.transform.position.x, placeBlock.transform.position.y, 0);
                            grabbedPawn.transform.position = blockPos;

                            if (grabbedPawn.transform.tag == "Chess")
                            {
                                for (int i = 0; i < 16; i++)
                                {
                                    if(grabbedPawn.transform.position == Whites[i].transform.position || grabbedPawn.transform.position == Blacks[15].transform.position)
                                    {
                                        if (grabbedPawn.transform.gameObject.layer != Whites[i].transform.gameObject.layer)
                                        {
                                            InvalidMove();
                                        }
                                    } else
                                    {
                                        WhiteKill();
                                    }
                                }
                            } else if (grabbedPawn.transform.tag == "Chess Black")
                            {
                                for (int i = 0; i < 16; i++)
                                {
                                    if (grabbedPawn.transform.position == Blacks[i].transform.position || grabbedPawn.transform.position == Whites[15].transform.position)
                                    {
                                        if (grabbedPawn.transform.gameObject.layer != Blacks[i].transform.gameObject.layer)
                                        {
                                            InvalidMove();
                                        }
                                    } else
                                    {
                                        BlackKill();
                                    }
                                }
                            }

                            grabbedPawn.gameObject.layer = 0;
                            SavePos();
                        }
                    }
                }
                else
                {
                    InvalidMove();
                }

                for (int f = 0; f < 16; f++)
                {
                    Whites[f].GetComponent<BoxCollider>().enabled = true;
                    Blacks[f].GetComponent<BoxCollider>().enabled = true;
                    grabbedPawn = null;

                    Vector3 whitesPos = new Vector3(Whites[f].transform.position.x, Whites[f].transform.position.y, 0);
                    Vector3 blacksPos = new Vector3(Blacks[f].transform.position.x, Blacks[f].transform.position.y, 0);
                    Whites[f].transform.position = whitesPos;
                    Blacks[f].transform.position = blacksPos;
                }
            }
        }

        if(grabbedPawn != null)
        {
            grabbedPawn.GetComponent<BoxCollider>().enabled = false;
            Vector3 mousePos = new Vector3(Camera.main.ScreenToWorldPoint(Input.mousePosition).x, Camera.main.ScreenToWorldPoint(Input.mousePosition).y, -1);
            grabbedPawn.transform.position = mousePos;
        }
    }

    public void InvalidMove()
    {
        placeBlock = null;

        for(int i = 0; i < 16; i++)
        {
            Whites[i].transform.position = whitesPos[i];
            Blacks[i].transform.position = blacksPos[i];
        }
    }

    public void SavePos()
    {
        for(int i = 0; i < 16; i++)
        {
            whitesPos[i] = new Vector3(Whites[i].transform.position.x, Whites[i].transform.position.y, 0);
            blacksPos[i] = new Vector3(Blacks[i].transform.position.x, Blacks[i].transform.position.y, 0);
        }
    }

    public void WhiteKill()
    {
        for(int i = 0; i < 16; i++)
        {
            if(grabbedPawn.transform.position == Blacks[i].transform.position)
            {
                Blacks[i].transform.position = blacksDeadPos[i];
                Blacks[i].transform.gameObject.layer = 2;
            }
        }
    }

    public void BlackKill()
    {
        for (int i = 0; i < 15; i++)
        {
            if (grabbedPawn.transform.position == Whites[i].transform.position)
            {
                Whites[i].transform.position = whitesDeadPos[i];
                Whites[i].transform.gameObject.layer = 2;
            }
        }
    }
}