using UnityEngine;
using System.Collections;

public class Block : MonoBehaviour 
{
	public GridPos Position; // Our current grid position
	
	private const float moveTime = 0.2f;
	private bool isMoving;
	
	void Update()
	{
		if (Position.Y > 0 && Map.Instance.Layout[Position+GridPos.Down] == null && !isMoving) // Are we above the first cell in our column, is the cell below us unoccupied and we are not currently moving?
		{
			StartCoroutine(MoveDown()); // Begin moving one cell down
		}
	}
	
	public void Matched()
	{
		Map.Instance.Layout[Position] = null; // Set our current position as occupied
		Destroy(gameObject); // Destroy this block
	}
	
	IEnumerator MoveDown()
	{
		isMoving = true; // We're moving!
		
		GridPos endPosGrid = new GridPos(Position.X, Position.Y-1);
		Vector3 startPos = transform.position;
		Vector3 endPos = Map.Instance.GridToWorld(endPosGrid);
		
		Map.Instance.Layout[Position] = null; // Mark our current position as unoccupied
		Map.Instance.Layout[endPosGrid] = this; // Mark our new position as occupied
		Position = endPosGrid;
		
		// Visually move to our new position over a set time
		float t = 0;
		while (t < moveTime)
		{
			transform.position = Vector3.MoveTowards(startPos, endPos, t/moveTime); // Lerp our position
			t += Time.deltaTime;
			yield return null;
		}
		
		transform.position = endPos; // Fix overshoot
		isMoving = false; // We're done moving
	}
}