Inventory Script

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

public class Inventory : MonoBehaviour
{
	//Size of inventory.
	public int invSlotsX;
	public int invSlotsY;

	public List<Item> inventory = new List<Item>(); //Slots taken up by an item.
	public List<Item> slots = new List<Item>(); //Empty inventory slots.

	public GUISkin skin;
	public GUISkin dragSkin;
	int guiDepth;

	private bool openInventory = false;

	private bool showTooltip;
	private string tooltip;

	private bool draggingItem;
	private Item draggedItem;
	private int draggedIndex;

	private ItemDatabase itemDB;

	public GameManager gm;
	public PlayerController pc;

	public Rect windowRect = new Rect(20, 20, 220, 300);

	// Use this for initialization
	void Start ()
	{
		//Allows this object to persist between scenes.
		//DontDestroyOnLoad(transform.gameObject);

		for(int i = 0; i < invSlotsX * invSlotsY; i++)
		{
			slots.Add (new Item());
			inventory.Add (new Item());
		}
		gm = GameObject.FindGameObjectWithTag("GM").GetComponent<GameManager>();
		pc = GameObject.FindGameObjectWithTag("Player").GetComponent<PlayerController>();
		itemDB = GameObject.FindGameObjectWithTag("Item Database").GetComponent<ItemDatabase>();
		/*AddItem(1);
		AddItem(0);
		AddItem(2);*/
	}

	void Update ()
	{
		//If player presses the Inventory button, change openInventory bool to the opposite of it's current
		//state. This allows you to both open and close the inventory with the same button.
		if (Input.GetButtonDown("Inventory"))
		{
			openInventory = !openInventory;
		}
		if (pc == null)
		{
			pc = GameObject.FindGameObjectWithTag("Player").GetComponent<PlayerController>();
		}
	}

	void OnGUI ()
	{
		Event e = Event.current;
		tooltip = "";
		GUI.skin = skin;
		GUI.skin = dragSkin;

		if(openInventory)
		{
			windowRect = GUI.Window(0, windowRect, DrawInventory, "Inventory", skin.GetStyle ("MainGUI"));
			//DrawInventory();
			if(showTooltip)
			{
				DrawTooltip();
			}
		}
		if(draggingItem)
		{
			GUI.depth = 0;
			GUI.DrawTexture(new Rect(e.mousePosition.x, e.mousePosition.y, 50, 50), draggedItem.itemIcon);
		}
	}

	//Displays the Inventory Window.
	private void DrawInventory (int windowID)
	{
		Event e = Event.current;
		int i = 0; //Inventory index counter.
		GUI.depth = 2;
		GUI.DragWindow(new Rect(0, 0, 10000, 20));
		//Y before X in order to draw rows instead of columns.
		for(int y = 0; y < invSlotsY; y++)
		{
			for(int x = 0; x < invSlotsX; x++)
			{
				Rect slotRect = new Rect(7 + (x * 52), 33 + (y * 52), 50, 50);
				//Draws a GUI Box made up of x by y "slots" with the defined GUI skin.
				GUI.depth = 1;
				GUI.Box(slotRect, "", skin.GetStyle("Inventory Slot"));
				slots[i] = inventory[i];
				Item item = slots[i];

				//If current slot contains an item...
				if (slots[i].itemName != null)
				{
					GUI.DrawTexture(slotRect, slots[i].itemIcon);
					if(slotRect.Contains(e.mousePosition))
					{
						if (!draggingItem)
						{
							tooltip = CreateTooltip(slots[i]);
							showTooltip = true;
						}

						//If mouse is clicking and dragging...
						if(e.button == 0 && e.type == EventType.mouseDrag && !draggingItem)
						{
							draggingItem = true;
							draggedIndex = i;
							draggedItem = slots[i]; //Set draggedItem to the item being moved.
							inventory[i] = new Item(); //Empty inventory slot that item is moved from.
						}

						//If mouse button has been released and an item was being dragged...
						if(e.type == EventType.mouseUp && draggingItem)
						{
							//Swaps item dragged with item in slot being hovered over.
							inventory[draggedIndex] = inventory[i];
							inventory[i] = draggedItem;
							draggingItem = false;
							draggedItem = null;
						}

						//If right mouse button is being clicked...
						if(e.isMouse && e.type == EventType.mouseDown && e.button == 1)
						{
							if(item.itemType == Item.ItemType.Consumable)
							{
								UseConsumable(slots[i],i,true);
							}
						}
					}
				}
				else
				{
					if(slotRect.Contains (e.mousePosition))
					{
						if(e.type == EventType.mouseUp && draggingItem)
						{
							//Drops item in to empty item slot.
							inventory[i] = draggedItem;
							draggingItem = false;
							draggedItem = null;
						}
					}
				}
				if(tooltip == "")
				{
					showTooltip = false;
				}
				i++; //Increment inventory index counter.
			}
		}
	}

	private void DrawTooltip()
	{
		//float dynamicSize = skin.box.CalcHeight(new GUIContent(tooltip), 200);
		Event e = Event.current;
		GUI.depth = -10;
		GUI.Box(new Rect(e.mousePosition.x + 10, e.mousePosition.y, 200, 200), tooltip, skin.GetStyle("Tooltip"));
	}

	private string CreateTooltip(Item item)
	{
		//Generates tooltips based on ItemType.
		if (item.itemType == Item.ItemType.Consumable)
		{
			tooltip = "<color=#ffffff><b>" + item.itemName + "</b></color>\n\n" + item.itemDesc + "\n\n" +
					"<b>Restores: </b>\n" + "HP: " + item.itemHealHP + "\n" + "MP: " + item.itemHealMP + "\n\n"
					+ "<color=#CCB75C><b>" + item.itemValue + "G</b></color>";
		}
		else if (item.itemType == Item.ItemType.Weapon)
		{
			tooltip = "<color=#ffffff><b>" + item.itemName + "</b></color>\n\n" + item.itemDesc + "\n\n" +
				"<b>Stats: </b>\n" + "Atk: " + item.itemAtk + "\n" + "M.Atk: " + item.itemMAtk + "\n" + "Spd: " + item.itemSpd
					+ "\n\n" + "Int: " + item.itemInt + "\n" + "Str: " + item.itemStr + "\n" + "Dex: " + item.itemDex + "\n\n"
					+ "<color=#CCB75C><b>" + item.itemValue + "G</b></color>";
		}
		else if (item.itemType == Item.ItemType.Armour || item.itemType == Item.ItemType.Accessory)
		{
			tooltip = "<color=#ffffff><b>" + item.itemName + "</b></color>\n\n" + item.itemDesc + "\n\n" +
					"<b>Stats: </b>\n" + "Def: " + item.itemDef + "\n" + "M.Def: " + item.itemMDef + "\n\n" + "Int: " + item.itemInt +
					"\n" + "Str: " + item.itemStr + "\n" + "Dex: " + item.itemDex + "\n\n" + "<color=#CCB75C><b>" + item.itemValue + "G</b></color>";
		}
		else if (item.itemType == Item.ItemType.Misc)
		{
			tooltip = "<color=#ffffff><b>" + item.itemName + "</b></color>\n\n" + item.itemDesc + "\n\n"
					+ "<color=#CCB75C><b>" + item.itemValue + "G</b></color>";
		}
		else if (item.itemType == Item.ItemType.Quest)
		{
			tooltip = "<color=#ffffff><b>" + item.itemName + "</b></color>\n\n" + item.itemDesc + "\n\n"
					+ "<color=#CCB75C><b>Quest Item</b></color>";
		}
		return tooltip;
	}

	//Add an item to the Player's inventory.
	public void AddItem(int id)
	{
		for(int i = 0; i < inventory.Count; i++)
		{
			//Check if inventory slot is empty.
			if (inventory[i].itemName == null)
			{
				for(int j = 0; j < itemDB.items.Count; j++)
				{
					//Find item with id matching the one passed in.
					if(itemDB.items[j].itemID == id)
					{
						//Put item in this empty slot.
						inventory[i] = itemDB.items[j];
					}
				}
				break;
			}
		}
	}

	//Remove an item from Player's inventory.
	public void RemoveItem(int id)
	{
		for (int i = 0; i < inventory.Count; i++)
		{
			//If item found in inventory...
			if (inventory[i].itemID == id)
			{
				inventory[i] = new Item(); //Change item to an empty slot.
				break;
			}
		}
	}

	//Check if an item already exists in the Player's inventory (can be used for quests/stacking, etc).
	public bool InventoryContains(int id)
	{
		for (int i = 0; i < inventory.Count; i++)
		{
			if (inventory[i].itemID == id)
			{
				return true;
			}
		}
		return false;
	}

	private void UseConsumable(Item item, int slot, bool deleteItem)
	{
		switch(item.itemID)
		{
			case 1:
			{
				//Restore 20HP.
				int healed = 20;
				print ("Used: " + item.itemName);
				pc.SendMessage("PlayerHealed", healed, SendMessageOptions.DontRequireReceiver);
				pc.SendMessage ("ConsumableUsed",SendMessageOptions.DontRequireReceiver);
				break;
			}
			case 2:
			{
				//Restore 50HP.
				int healed = 50;
				print ("Used: " + item.itemName);
				pc.SendMessage("PlayerHealed", healed, SendMessageOptions.DontRequireReceiver);
				pc.SendMessage ("ConsumableUsed",SendMessageOptions.DontRequireReceiver);
				break;
			}
		}
		if (deleteItem)
		{
			inventory[slot] = new Item();
		}
	}

	private void EquipItem(Item item, int slot, bool deleteItem)
	{
		if(item.itemType == Item.ItemType.Weapon)
		{
			pc.atk += item.itemAtk;
			pc.mAtk += item.itemMAtk;
			pc.atkSpd += item.itemSpd;
		}
	}
}