/**
 ********************************************************************************
 * Copyright (c) 2019 Dortmund University of Applied Sciences and Arts and others.
 *
 * This program and the accompanying materials are made
 * available under the terms of the Eclipse Public License 2.0
 * which is available at https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Dortmund University of Applied Sciences and Arts - initial API and implementation
 ********************************************************************************
 */

package org.eclipse.app4mc.multicore.execution.logic.systemproxy.multicoresystem;

import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import org.eclipse.app4mc.multicore.execution.logic.openmapping.MalformedModelException;
import org.eclipse.app4mc.multicore.execution.logic.openmapping.OMAllocation;
import org.eclipse.app4mc.multicore.execution.logic.openmapping.OMCore;
import org.eclipse.app4mc.multicore.execution.logic.openmapping.OMMapping;
import org.eclipse.app4mc.multicore.execution.logic.openmapping.OMTask;
import org.eclipse.app4mc.multicore.execution.logic.openmapping.OMUtil;
import org.eclipse.app4mc.multicore.execution.logic.systemproxy.SimException;

public class SimUtil {
	
	private SimUtil() {
		
	}

	public static void validateModelForSimulation(final OMMapping mapping) throws SimException {
		validateOnlyPeriodicTasks(mapping);
		try {
			validateUtilizationPerCore(mapping);
		}
		catch (final MalformedModelException e) {
			throw new SimException(e.getMessage());
		}
	}

	public static void validateOnlyPeriodicTasks(final OMMapping model) throws SimException {
		for (final OMAllocation alloc : model.getAllocationList()) {
			final long p = alloc.getTask().getPeriod();
			if (p == 0) {
				throw new SimException(
						"Non-periodic or unset period at task: " + alloc.getTask().getTaskRef().getName());
			}
		}
	}

	/**
	 * Check if every core has a utilization less 100%.
	 *
	 * @param model
	 * @return
	 * @throws SimException
	 * @throws MalformedModelException
	 */
	public static void validateUtilizationPerCore(final OMMapping model) throws SimException, MalformedModelException {
		final Map<OMCore, List<OMTask>> tasksPerCore = OMUtil.getCoreTaskMap(model.getAllocationList());
		validateUtilizationPerCore(tasksPerCore);
	}

	/**
	 * Check if every core has a utilization less 100%.
	 *
	 * @param model
	 * @return
	 * @throws MalformedModelException
	 */
	public static void validateUtilizationPerCore(final Map<OMCore, List<OMTask>> model)
			throws SimException, MalformedModelException {
		for (final Entry<OMCore,List<OMTask>> c : model.entrySet()) {
			final double utila = OMUtil.getUtilization(c.getKey(), c.getValue());
			if (utila > 1) {
				// "Mapping for simulation has at least one core with an
				// utilization greater 1!"
				// a simExecption should be thrown here
			}
		}
	}

	/**
	 * Scale the passed positive value with roundup. Example:
	 * <ul>
	 * <li>val = 141; scale = 10 => 15</li>
	 * <li>val = 2611; scale = 1000 => 3</li>
	 * </ul>
	 *
	 * @param val
	 *            Value to scale down (rounding up).
	 * @param scale
	 *            Divisor for scale down.
	 * @return Scaled down value (rounded up).
	 */
	public static long scaleRoundUp(final long val, final long scale) {
		return val / scale + ((val % scale) != 0 ? 1 : 0);
	}
}