package com.flaremicro.visualforecast;
/**
 * TImer class, deals with ticks, game speedup, and slowdown
 * @author Vulpovile
 *
 */
public class Timer {
	private final int ticksPerSecond;
	private long lastTickTime = 0;
	private long currentTime = 0;
	private long ticksPassed = 0;
	/**
	 * Creates a timer with a set amount ticks per second
	 * @param ticksPerSecond
	 */
	public Timer(int ticksPerSecond)
	{
		this.ticksPerSecond = 1000/ticksPerSecond;
		currentTime = System.currentTimeMillis();
		lastTickTime = currentTime;
	}
	/**
	 * Resets the timer, prevents the superspeed bug when loading or generating levels
	 */
	public void reset()
	{
		currentTime = System.currentTimeMillis();
		lastTickTime = currentTime;
	}
	/**
	 * Ticks the timer and returns how many ticks were missed by the game (to catch up with bad framerates)
	 * @return ticks passed
	 */
	public long tick()
	{
		if(ticksPassed > 0) ticksPassed--;
		currentTime = System.currentTimeMillis();
		if(lastTickTime < currentTime-ticksPerSecond)
		{
			ticksPassed = (currentTime-lastTickTime)/ticksPerSecond;
			lastTickTime = currentTime - (currentTime-lastTickTime)%ticksPerSecond;
		}
		if(ticksPassed > 200L)
		{
			System.out.println("Time moving too fast! Did the system time change or is the game overloaded?");
			System.out.println("Moving time forward " + ticksPassed + " ticks");
			ticksPassed = 0;
		}
		else if(ticksPassed < 0L)
		{
			System.out.println("Time moved backwards! Did the system time change?");
			System.out.println("Moving time backwards " + -ticksPassed + " ticks");
			ticksPassed = 0;
		}
		return ticksPassed;
	}
}