package me.hammerle.supersnuvi.snuviscript;

import java.util.ArrayList;
import me.hammerle.snuviscript.code.ISnuviScheduler;
import me.hammerle.supersnuvi.gamelogic.Level;

public class SnuviScheduler implements ISnuviScheduler
{
    private static class Task
    {
        private final Runnable r;
        private long ticks;
        private final Level owner;
        
        private Task(Runnable r, long ticks, Level owner)
        {
            this.r = r;
            this.ticks = ticks;
            this.owner = owner;
        }
        
        private boolean tick(Level current)
        {
            if(current != owner && owner != null)
            {
                return false;
            }
            ticks--;
            if(ticks <= 0)
            {
                r.run();
                return true;
            }
            return false;
        }
    }
    
    private int id = 0;
    private final ArrayList<Task> queue = new ArrayList<>();
    
    private Level currentLevel = null;
    
    public void setActiveLevel(Level l)
    {
        currentLevel = l;
    }
    
    @Override
    public int scheduleTask(Runnable r, long delay)
    { 
        queue.add(new Task(r, Math.max(delay, 2), currentLevel));
        return id++;
    }
    
    @Override
    public int scheduleTask(Runnable r)
    { 
        return scheduleTask(r, 2);
    }
    
    public void tick(Level current)
    {
        int i = 0;
        while(i < queue.size())
        {
            if(queue.get(i).tick(current))
            {
                if(i + 1 == queue.size())
                {
                    // last element
                    queue.remove(i);
                }
                else
                {
                    // swap last
                    queue.set(i, queue.get(queue.size() - 1));
                    queue.remove(queue.size() - 1);
                    // current element is a new one, skip i++
                    continue;
                }
            }
            i++;
        }
    }    
}