package example.timeestimation;

import gssim.schedframe.scheduling.ExecTaskInterface;

import java.util.List;
import java.util.Map;
import java.util.Properties;

import schedframe.resources.units.ResourceUnit;
import schedframe.scheduling.TaskInterface;
import schedframe.scheduling.events.SchedulingEvent;
import schedframe.scheduling.plugin.SchedulingPluginConfiguration;
import schedframe.scheduling.utils.ResourceParameterName;
import test.rewolucja.resources.ProcessingElements;
import test.rewolucja.resources.physical.implementation.CPU;


/**
 * 
 * @author Marcin Krystek
 *
 */
public class ExecTimeEstimationPlugin implements schedframe.scheduling.plugin.estimation.ExecTimeEstimationPlugin{

	/*
	 * This method should return an estimation of time required to execute the task.
	 * Requested calculation should be done based on the resources allocated for the task,
	 * task description and task remaining length (in instructions).
	 * 
	 * Example implementation calculate the estimation based on cpu processing power.
	 * There is also a simple assumption, that cpu processing power is a linear function
	 * of number of allocated cpus and their speed.
	 */
	public double execTimeEstimation(SchedulingEvent event,
			Map<ResourceParameterName, ResourceUnit> allocatedResources,
			ExecTaskInterface task, double completionPercentage) {
		
		// collect all information necessary to do the calculation
		ProcessingElements pes = (ProcessingElements) allocatedResources.get(ResourceParameterName.PROCESSINGELEMENTS);


		int speed = pes.getSpeed();
		int cnt = pes.getAmount();
		
		// number of used processors  

		double remainingLength =  task.getLength() * (1- completionPercentage);
		// do the calculation
		double execTime = (remainingLength / (cnt * speed));

		// if the result is very close to 0, but less then one millisecond then round this result to 0.001
		if (Double.compare(execTime, 0.001) < 0) {
			execTime = 0.001;
		}

		// time is measured in integer units, so get the nearest execTime int value.
		execTime = Math.ceil(execTime);
		return execTime;
	}

	public SchedulingPluginConfiguration getConfiguration() {
		// This plugin in not expected to have any specific configuration.
		return null;
	}

	public String getName() {
		return "ExampleTimeEstimationPlugin";
	}

	public void init(Properties properties) {
		/* 
		 * This method should be called by AbstractAllocationPolicy or any class that extends
		 * AbstractAllocationPolicy. Default implementation does not invoke it.
		 */
	}

}