A simple trade system for UFPS

gistfile1.cs

using UnityEngine;
using System.Collections;

public class SimpleTrade : MonoBehaviour {

	public vp_Inventory inventory; 
	public vp_UnitType required_item;
	public vp_ItemType given_item;

	void OnTriggerEnter( Collider col ){

		if( col.gameObject.tag == "Player" ){

			if( inventory == null ){
				inventory = col.gameObject.GetComponent<vp_Inventory>();
			}

			if( inventory.HaveInternalUnitBank( required_item ) ){

				if( inventory.GetUnitCount( required_item ) > 0 ){

					inventory.TryRemoveUnits( required_item, 1 );
					inventory.TryGiveItem( given_item, 1 );

					Debug.Log( "Thank you for the " + required_item.DisplayName + ", I have given you " + given_item.IndefiniteArticle + " " + given_item.DisplayName );

				}else{

					Debug.Log( "You have no " + required_item.DisplayName + "s. :(" );

				}

			}

		}

	}

}