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

public class ProceduralGridTerrain : MonoBehaviour
{

    public GameObject terrainPrefab;
    [SerializeField] private int width = 24;
    [SerializeField] private int height = 32;
    private GameObject[,] terrainList;
    private bool isDirty = true;
    public float offsetX;
    public float offsetY;
    [SerializeField] private float step = 0.2f;
    void Awake()
    {
        Debug.Log( "Setting up Terrain" );
        terrainList = new GameObject[width, height];
        for( int x = 0; x < width; x++ )
        {
            for( int y = 0; y < height; y++ )
            {
                //Debug.Log( x + ", " + y );
                Vector3 pos = transform.position + new Vector3( x, 0, y );
                terrainList[x, y] = Instantiate( terrainPrefab, pos, transform.rotation, transform );
                terrainList[x, y].name = "Tile " + x + "," + y;
            }
        }
        //UpdateTerrainLoc();
    }

    // Update is called once per frame
    void Update()
    {

        if( Input.GetKeyDown( KeyCode.U ) )
        {
            offsetY += step;
            isDirty = true;
        }

        if( Input.GetKeyDown( KeyCode.H ) )
        {
            offsetX -= step;
            isDirty = true;
        }

        if( Input.GetKeyDown( KeyCode.J ) )
        {
            offsetY -= step;
            isDirty = true;
        }

        if( Input.GetKeyDown( KeyCode.K ) )
        {
            offsetX += step;
            isDirty = true;
        }
        if( isDirty )
            UpdateTerrainLoc();

    }

    void UpdateTerrainLoc()
    {
        for( int x = 0; x < width; x++ )
        {
            for( int y = 0; y < height; y++ )
            {
                float xDiff = x * .01f + offsetX;
                float yDiff = y * .01f + offsetY;



                float loc = Mathf.Round( Mathf.PerlinNoise( xDiff, yDiff ) * 20 );
                Debug.Log( xDiff + ", " + yDiff + ", " + loc);
                Vector3 pos = terrainList[x, y].transform.position;
                pos.y = loc;
                terrainList[x, y].transform.position = pos;
            }
        }
        isDirty = false;
    }

    public float getTerrainHeight( int x, int y )
    {
        return terrainList[x, y].transform.position.y;
    }
    public float getTerrainHeight( Vector2Int loc )
    {
        if( terrainList[loc[0], loc[1]] )
        {
            Debug.Log( terrainList[loc[0], loc[1]].transform.position );
            float y = terrainList[loc[0], loc[1]].transform.position.y;
            return y;
        }
        return -999;

    }
}