//Terrain Grid
using UnityEngine;
using System.Collections;
using Gamelogic;
using Gamelogic.Grids;

[RequireComponent(typeof(MeshCollider))]
public class TerrainGrid : GLMonoBehaviour {

    public TerrainCell terrainCell;
    private RectGrid<TerrainCell> grid;
    private IMap3D<RectPoint> map;

    public int width = 10;
    public int height = 10;
    public bool buildOnStart = false;

    void Start () {
    if(buildOnStart)
            BuildGrid();
    }

    [ContextMenu("Build Grid")]
    private void BuildGrid() {
        grid = RectGrid<TerrainCell>.Rectangle(width-1, height-1);
        map = new RectMap(new Vector2(1f, 1f)).To3DXZ();

        foreach (RectPoint point in grid) {
            TerrainCell cell = Instantiate(terrainCell);
            Vector3 worldPoint = map[point];

            cell.transform.parent = this.gameObject.transform;
            cell.transform.localScale = Vector3.one;
            cell.transform.localPosition = worldPoint + new Vector3(0.5f, 10f, 0.5f);

            cell.Generate();
            cell.HighlightOn = false;
            grid[point] = cell;
        }
    }

    void Update () {
        if (Input.GetMouseButtonDown(0)) {
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            RaycastHit hit;

            if (Physics.Raycast(ray, out hit)) {
                Vector3 worldPosition = this.gameObject.transform.InverseTransformPoint(hit.point);
                RectPoint gridPoint = new RectPoint((int)hit.point.x, (int)hit.point.z);

                if (grid.Contains(gridPoint)) {
                    Debug.Log("Found");
                    grid[gridPoint].HighlightOn = !grid[gridPoint].HighlightOn;
                    grid[gridPoint].__UpdatePresentation(true);
                } else {
                    Debug.Log("couldn't find grid point");
                }

            } else {
                Debug.Log("Didn't hit anything");
            }
        }
    }
}


//Cell class
using UnityEngine;
using System.Collections;
using Gamelogic.Grids;
using System.Collections.Generic;

public class TerrainCell : MeshTileCell {

    public Material material;

    private MeshFilter meshFilter;
    private MeshRenderer meshRenderer;
    private Mesh mesh;

    private float yheight = 0.01f; //prevent fighting

    [HideInInspector]
    public Vector3 topLeft;
    [HideInInspector]
    public Vector3 topRight;
    [HideInInspector]
    public Vector3 bottomRight;
    [HideInInspector]
    public Vector3 bottomLeft;

    public void Generate() {
        meshFilter = this.gameObject.AddComponent<MeshFilter>();
        meshRenderer = this.gameObject.AddComponent<MeshRenderer>();
        mesh = new Mesh();
        meshFilter.mesh = mesh;
        meshRenderer.material = material;

        List<Vector3> verts = new List<Vector3>();

        topLeft = new Vector3(-0.5f, 0f, -0.5f);
        topRight = new Vector3(0.5f, 0f, -0.5f);
        bottomLeft = new Vector3(-0.5f, 0f, 0.5f);
        bottomRight = new Vector3(0.5f, 0f, 0.5f);

        topLeft = GetHeightAtRaycast(topLeft);
        topRight = GetHeightAtRaycast(topRight);
        bottomLeft = GetHeightAtRaycast(bottomLeft);
        bottomRight = GetHeightAtRaycast(bottomRight);


        verts.Add(topLeft);
        verts.Add(topRight);
        verts.Add(bottomLeft);
        verts.Add(bottomRight);

        List<int> triangles = new List<int>();

        triangles.Add(2);
        triangles.Add(1);
        triangles.Add(0);

        triangles.Add(2);
        triangles.Add(3);
        triangles.Add(1);

        List<Color32> colors = new List<Color32>();
        colors.Add(new Color32(0, 0, 0, 0));
        colors.Add(new Color32(0, 0, 0, 0));
        colors.Add(new Color32(0, 0, 0, 0));
        colors.Add(new Color32(0, 0, 0, 0));

        mesh.vertices = verts.ToArray();
        mesh.triangles = triangles.ToArray();
        mesh.colors32 = colors.ToArray();
        mesh.Optimize();
        mesh.RecalculateBounds();
        mesh.RecalculateNormals();

        Vector3 pos = this.gameObject.transform.localPosition;
        pos.y = yheight;
        this.gameObject.transform.localPosition = pos;
    }

    private Vector3 GetHeightAtRaycast(Vector3 position) {
        Ray ray = new Ray(position + this.gameObject.transform.position, Vector3.down);
        RaycastHit hit;
        if (Physics.Raycast(ray, out hit)) {
            position.y = hit.point.y;
            return position;
        } else {
            Debug.LogError("Raycast failed, this isn't allowed to happen!");
            return Vector3.zero;
        }
    }
}