Inventory1

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

public class GridE : MonoBehaviour
{
    public Transform Element;
    public Transform InstEl;
    public Vector2 ElementScale = new Vector2(30,30);
    public List<Transform> AllCells = new List<Transform> ();
    Vector3 startpoint;
    public Transform CellsParent;
    public Transform GridHorizontalLine;
    public Transform GridVerticalLine;
    public Vector2 GridScale = new Vector2(11,4);
    public List<Transform> AllItems = new List<Transform> ();
    public Transform SelectedItem;
    public Transform SelectedCell;

    public List<Transform> HowerCells = new List<Transform> ();

    public Transform Item1;
    public Transform Item2;
    public Transform Item3;
    public Transform Item4;


    public void InstLines()
    {
        for (int y = 0; y < 4; y++)
        {
            Transform HorLine = Instantiate (GridHorizontalLine, startpoint + new Vector3 (0, -y * ElementScale.y, 0), Quaternion.identity) as Transform;
            HorLine.SetParent (transform);
        }
    }


    public void Awake ()
    {
        startpoint = new Vector3 (Screen.width-400, 200, 0);
        for (int x = 0; x < GridScale.x; x++)
        {
            Transform CellX = Instantiate (Element, startpoint+new Vector3(x*ElementScale.x,0,0), Quaternion.identity) as Transform;
            CellX.SetParent (CellsParent);
            AllCells.Add (CellX);
            CellX.GetComponent<RectTransform> ().sizeDelta = ElementScale;
            for (int y = 1; y < GridScale.y; y++)
            {
                Transform CellY = Instantiate (Element, startpoint+new Vector3(x*ElementScale.x,-y*ElementScale.y,0), Quaternion.identity) as Transform;
                CellY.SetParent (CellsParent);
                AllCells.Add (CellY);
                CellY.GetComponent<RectTransform> ().sizeDelta = ElementScale;
            }
        }

        for (int y = 1; y < GridScale.y; y++)
        {
            Transform HorLine = Instantiate (GridHorizontalLine, startpoint + new Vector3 (0, -y * ElementScale.y, 0) + new Vector3((GridScale.x-1)*ElementScale.x/2,ElementScale.y/2,0), Quaternion.identity) as Transform;
            HorLine.GetComponent<RectTransform> ().sizeDelta = new Vector2(GridScale.x*ElementScale.x,1);
            HorLine.SetParent (CellsParent);
        }

        for (int x = 1; x < GridScale.x; x++)
        {
            Transform VerLine = Instantiate (GridVerticalLine, startpoint+new Vector3(x*ElementScale.x,0)+new Vector3(-ElementScale.x/2,(-GridScale.y+1)*ElementScale.y/2,0),Quaternion.identity) as Transform;
            VerLine.GetComponent<RectTransform> ().sizeDelta = new Vector2(1,GridScale.y*(ElementScale.y+1));
            VerLine.SetParent (CellsParent);
        }



        Transform item = Instantiate (Item1, startpoint+new Vector3(15,-15,0),Quaternion.identity) as Transform;
        item.SetParent (transform);
        AllItems.Add (item);

        Transform item2 = Instantiate (Item2, startpoint+new Vector3(ElementScale.x*3,-15,0),Quaternion.identity) as Transform;
        item2.SetParent (transform);
        AllItems.Add (item2);

        Transform item3 = Instantiate (Item3, startpoint+new Vector3(ElementScale.x*5,0,0),Quaternion.identity) as Transform;
        item3.SetParent (transform);
        AllItems.Add (item3);

        Transform item4 = Instantiate (Item4, startpoint+new Vector3(ElementScale.x*7-15,-30,0),Quaternion.identity) as Transform;
        item4.SetParent (transform);
        AllItems.Add (item4);
    }

    public void DestroyGrid()
    {
        foreach (Transform tr in AllCells)
        {
            DestroyImmediate (tr.gameObject);
        }
        AllCells.Clear ();
    }


    void Update()
    {
        if (Input.GetMouseButtonDown (0))
        {
            Vector2 mouse = new Vector2(Input.mousePosition.x, Screen.height - Input.mousePosition.y);
            foreach (Transform tr in AllItems)
            {
                if (RectTransformUtility.RectangleContainsScreenPoint (tr.GetComponent<RectTransform> (), Input.mousePosition))
                {
                    SelectedItem = tr;
                }
            }
        }
        if (SelectedItem != null)
        {
            SelectedItem.position = Input.mousePosition;

            Vector3 MousePos = Input.mousePosition;
            MousePos = new Vector3 (Mathf.Clamp(MousePos.x,
                startpoint.x+(SelectedItem.GetComponent<InventoryItem> ().Scale.x-1)*ElementScale.x/2,
                startpoint.x+(int)(GridScale.x-1)*ElementScale.x-SelectedItem.GetComponent<InventoryItem> ().Scale.x*ElementScale.x/2),
                Mathf.Clamp(MousePos.y,
                    startpoint.y-(int)((GridScale.y-1)*ElementScale.y)+SelectedItem.GetComponent<InventoryItem> ().Scale.y*ElementScale.y/2,
                    startpoint.y-(SelectedItem.GetComponent<InventoryItem> ().Scale.y-1)*ElementScale.y/2),
                MousePos.z);



            Vector3 LeftUpPoint = MousePos + new Vector3 (-SelectedItem.GetComponent<InventoryItem> ().Scale.x*ElementScale.x / 2+ElementScale.x / 2, SelectedItem.GetComponent<InventoryItem> ().Scale.y*ElementScale.y / 2-ElementScale.y / 2, 0);
            foreach (Transform tr in AllCells)
            {
                if (RectTransformUtility.RectangleContainsScreenPoint (tr.GetComponent<RectTransform> (), LeftUpPoint))
                {
                    SelectedCell = tr;
                }
            }

            if (SelectedCell != null)
            {
                HowerCells.Add (SelectedCell);
                foreach (Transform tr in AllCells)
                {
                    for (int x = 0; x < SelectedItem.GetComponent<InventoryItem> ().Scale.x; x++)
                    {
                        for (int y = 0; y < SelectedItem.GetComponent<InventoryItem> ().Scale.y; y++)
                        {
                            if (tr.localPosition == SelectedCell.localPosition + new Vector3(ElementScale.x*x,-ElementScale.y*y,0))
                            {
                                HowerCells.Add (tr);
                            }
                        }
                    }

                    if (HowerCells.Contains (tr))
                    {
                        tr.GetComponent<Image> ().color = new Color (0, 1, 0);
                    } else
                    {
                        tr.GetComponent<Image> ().color = new Color (0.3f, 0.3f, 0.3f);
                    }
                }

                HowerCells.Clear ();
            }
        }
    }
}