/**
 ********************************************************************************
 * Copyright (c) 2015-2020 Robert Bosch GmbH 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:
 *     Robert Bosch GmbH - initial API and implementation
 ********************************************************************************
 */

package org.eclipse.app4mc.amalthea.converters072.impl;

import java.io.File;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.app4mc.amalthea.converters.common.ServiceConstants;
import org.eclipse.app4mc.amalthea.converters.common.base.ICache;
import org.eclipse.app4mc.amalthea.converters.common.base.IConverter;
import org.eclipse.app4mc.amalthea.converters.common.converter.AbstractConverter;
import org.eclipse.app4mc.amalthea.converters.common.utils.AmaltheaNamespaceRegistry;
import org.eclipse.app4mc.amalthea.converters.common.utils.HelperUtil;
import org.jdom2.Attribute;
import org.jdom2.Document;
import org.jdom2.Element;
import org.osgi.service.component.annotations.Activate;
import org.osgi.service.component.annotations.Component;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Component(
		property = {
			ServiceConstants.INPUT_MODEL_VERSION_PROPERTY + "=0.7.1",
			ServiceConstants.OUTPUT_MODEL_VERSION_PROPERTY + "=0.7.2"},
		service = IConverter.class)

public class SwConverter extends AbstractConverter {

	private static final Logger LOGGER = LoggerFactory.getLogger(SwConverter.class);

	@Override
	@Activate
	protected void activate(Map<String, Object> properties) {
		super.activate(properties);
	}

	@Override
	public void convert(File targetFile, Map<File, Document> filename2documentMap, List<ICache> caches) {

		LOGGER.info(
				"Migration from 0.7.1 to 0.7.2 : Executing SW converter for model file : {}", targetFile.getName());


		final Document root = filename2documentMap.get(targetFile);

		if (root == null) {
			return;
		}
		final Element rootElement = root.getRootElement();

		updateBuffering(rootElement);
		updateSamplingType(rootElement);
		updateInstructionsConstant(rootElement);
		updateInstructionsDeviation(rootElement);
		updateProbabilityGroup(rootElement);
		updateGroup(rootElement);
		updatePreemption(rootElement);
	}

	/**
	 * This method is used to migrate the "buffered" attribute of Label and LabelAccess
	 *
	 * For migration of buffered attribute inside Label, below are the steps which are followed:
	 *
	 * <pre>
	 *
	 * *. LabelBufferring is replaced with DataStability element
	 * 		-  If LabelBuffering value is "buffered" then the corresponding value of "dataStability" is set as "CustomProtection"
	 * 		-  If LabelBuffering value is "notBuffered" then the corresponding value of "dataStability" is set as "noProtection"
	 * 		-  If LabelBuffering value is "_undefined_" (default) then the corresponding value of "dataStability" is set as "_undefined_" (default)
	 *
	 * </pre>
	 *
	 * *For migration of buffered attribute inside LabelAccess, below are the steps which are followed:
	 *
	 * <pre>
	 *
	 * *. LabelAccessBufferring is replaced with DataStability element
	 * 		-  If LabelAccessBufferring value is "inherited" then the corresponding value of "dataStability" is set as "inherited"
	 * 		-  If LabelAccessBufferring value is "buffered" then the corresponding value of "dataStability" is set as "customProtection"
	 * 		-  If LabelAccessBufferring value is "notBuffered" then the corresponding value of "dataStability" is set as "noProtection"
	 * 		-  If LabelAccessBufferring value is "_undefined_" (default) then the corresponding value of "dataStability" is set as "_undefined_" (default)
	 *
	 * </pre>
	 *
	 * @param rootElement
	 */
	private void updateBuffering(final Element rootElement) {

		final StringBuilder labelXpathBuffer = new StringBuilder();

		labelXpathBuffer.append("./swModel/labels");

		final List<Element> elements = HelperUtil.getXpathResult(
				rootElement,
				labelXpathBuffer.toString(),
				Element.class,
				AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element labelElement : elements) {

			final Attribute bufferedAttribute = labelElement.getAttribute("buffered");

			if (bufferedAttribute != null) {

				bufferedAttribute.setName("dataStability");

				final String bufferedValue = bufferedAttribute.getValue();

				if (bufferedValue.equals("buffered")) {
					bufferedAttribute.setValue("customProtection");

				}
				else if (bufferedValue.equals("notBuffered")) {
					bufferedAttribute.setValue("noProtection");
				}
			}
		}

		final StringBuilder labelAccessXpathBuffer = new StringBuilder();

		labelAccessXpathBuffer.append("./swModel/runnables//runnableItems[@xsi:type=\"am:LabelAccess\"]");
		labelAccessXpathBuffer.append("|");
		labelAccessXpathBuffer.append("./swModel/runnables//runnableItem[@xsi:type=\"am:LabelAccess\"]");

		final List<Element> labelAccesselements = HelperUtil.getXpathResult(rootElement,
				labelAccessXpathBuffer.toString(), Element.class, AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element labelAccessElement : labelAccesselements) {

			final Attribute bufferedAttribute = labelAccessElement.getAttribute("buffered");

			if (bufferedAttribute != null) {

				bufferedAttribute.setName("dataStability");

				final String bufferedValue = bufferedAttribute.getValue();

				if (bufferedValue.equals("inherited")) {
					bufferedAttribute.setValue("inherited");

				}
				else if (bufferedValue.equals("buffered")) {
					bufferedAttribute.setValue("customProtection");
				}
				else if (bufferedValue.equals("notBuffered")) {
					bufferedAttribute.setValue("noProtection");
				}
			}

		}


	}

	/**
	 *
	 * SamplingType Enum is part of Deviation object till 0.7.1
	 *
	 * Based on bugzilla : 508523, SamplingType is shifted from Deviation element to Boundaries element (sub-class of
	 * Distribution)
	 *
	 * -- As a part of migration, SamplingType content part of Deviation is associted to Boundaries. In case
	 * Distribution of type Distribution is not present inside Deviation, SamplingType content is not associated and
	 * lost (as expected)
	 *
	 * Note: Deviation element is used inside Stimulus model, HW model, OS model, SW model
	 *
	 * @param rootElement
	 */

	private void updateSamplingType(final Element rootElement) {

		final StringBuilder xpathBuffer = new StringBuilder();

		xpathBuffer.append("./stimuliModel/stimuli/stimulusDeviation");
		xpathBuffer.append("|");
		xpathBuffer.append("./hwModel/accessPaths/latencies[@xsi:type=\"am:LatencyDeviation\"]/deviation");
		xpathBuffer.append("|");
		xpathBuffer.append("./osModel/operatingSystems/taskSchedulers/schedulingUnit/instructions/deviation");
		xpathBuffer.append("|");

		xpathBuffer.append("./osModel/operatingSystems/interruptControllers/schedulingUnit/instructions/deviation");
		xpathBuffer.append("|");

		xpathBuffer.append("./osModel/osOverheads//deviation");
		xpathBuffer.append("|");

		xpathBuffer.append("./swModel/runnables//deviation");


		final List<Element> elements = HelperUtil.getXpathResult(rootElement, xpathBuffer.toString(), Element.class,
				AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element deviation : elements) {
			/*- updating the type of the Element as per change introduced in 0.7.2*/
			final Attribute samplingTypeAttribute = deviation.getAttribute("samplingType");

			if (samplingTypeAttribute != null) {
				final String value = samplingTypeAttribute.getValue();

				final Element distribution = deviation.getChild("distribution");

				if (distribution != null) {

					final String distributionType = distribution.getAttributeValue("type",
							AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

					/*- Setting "samplingType" to "distribution" --> only if the distribution element is of type  "am:Boundaries"  */
					if (distributionType != null && distributionType.equals("am:Boundaries")) {
						distribution.setAttribute("samplingType", value);
					}
				}

				deviation.removeAttribute(samplingTypeAttribute);

			}

		}


	}

	private void updateInstructionsConstant(final Element rootElement) {

		final StringBuilder xpathBuffer = new StringBuilder();

		xpathBuffer.append("./swModel/runnables//runnableItems[@xsi:type=\"am:InstructionsConstant\"]");
		xpathBuffer.append("|");
		xpathBuffer.append("./swModel/runnables//runnableItem[@xsi:type=\"am:InstructionsConstant\"]");

		final List<Element> elements = HelperUtil.getXpathResult(rootElement, xpathBuffer.toString(), Element.class,
				AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element instructionsConstantElement : elements) {
			/*- updating the type of the Element as per change introduced in 0.7.2*/
			final Attribute typeAttribute = instructionsConstantElement.getAttribute("type",
					AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));
			typeAttribute.setValue("am:RunnableInstructions");

			final Attribute valueAttribute = instructionsConstantElement.getAttribute("value");


			final Element subInstructionsConstantElement = new Element("default");
			subInstructionsConstantElement.setAttribute("type", "am:InstructionsConstant",
					AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

			if (valueAttribute != null) {
				subInstructionsConstantElement.setAttribute("value", valueAttribute.getValue());
				instructionsConstantElement.removeAttribute(valueAttribute);
			}

			instructionsConstantElement.addContent(subInstructionsConstantElement);
		}


	}

	private void updateInstructionsDeviation(final Element rootElement) {

		final StringBuilder xpathBuffer = new StringBuilder();

		xpathBuffer.append("./swModel/runnables//runnableItems[@xsi:type=\"am:InstructionsDeviation\"]");
		xpathBuffer.append("|");
		xpathBuffer.append("./swModel/runnables//runnableItem[@xsi:type=\"am:InstructionsDeviation\"]");

		final List<Element> elements = HelperUtil.getXpathResult(rootElement, xpathBuffer.toString(), Element.class,
				AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element instructionsDeviationElement : elements) {
			/*- updating the type of the Element as per change introduced in 0.7.2*/
			final Attribute typeAttribute = instructionsDeviationElement.getAttribute("type",
					AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));
			typeAttribute.setValue("am:RunnableInstructions");


			final Element subInstructionsDeviationElement = new Element("default");
			subInstructionsDeviationElement.setAttribute("type", "am:InstructionsDeviation",
					AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

			final List<Element> instructionsDeviationChildElements = instructionsDeviationElement.getChildren();

			final Iterator<Element> instructionsDeviationChildElements_iterator = instructionsDeviationChildElements
					.iterator();

			while (instructionsDeviationChildElements_iterator.hasNext()) {

				final Element nextChildElement = instructionsDeviationChildElements_iterator.next();

				instructionsDeviationChildElements_iterator.remove();

				subInstructionsDeviationElement.addContent(nextChildElement);
			}

			instructionsDeviationElement.addContent(subInstructionsDeviationElement);
		}


	}


	private void updatePreemption(final Element rootElement) {

		final StringBuilder xpathBuffer = new StringBuilder();

		xpathBuffer.append("./swModel/processPrototypes[@preemption=\"unknown\"]");
		xpathBuffer.append("|");
		xpathBuffer.append("./swModel/tasks[@preemption=\"unknown\"]");

		final List<Element> elements = HelperUtil.getXpathResult(rootElement, xpathBuffer.toString(), Element.class,
				AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element element : elements) {
			element.removeAttribute("preemption");
		}


	}

	/**
	 * Due to removal of element : DeviationRunnableItem
	 *
	 *
	 * @param rootElement
	 */
	private void updateGroup(final Element rootElement) {

		/*-
		 * Input :
		 *
		 *    <runnableItems xsi:type="am:Group" ordered="false">
		 *		<items>
		 *  			<runnableItem xsi:type="am:RunnableProbabilitySwitch">
		 *    			<entries probability="0" />
		 *	 		</runnableItem>
		 *		</items>
		 *	</runnableItems>
		 *
		 */
		final StringBuilder xpathBuffer = new StringBuilder();

		xpathBuffer.append("./swModel/runnables//runnableItems[@xsi:type=\"am:Group\"]");
		xpathBuffer.append("|");
		xpathBuffer.append("./swModel/runnables//runnableItem[@xsi:type=\"am:Group\"]");
		xpathBuffer.append("|");
		xpathBuffer.append(
				"./swModel/runnables//items[@xsi:type=\"am:Group\"]"); /*- note: the last Xpath is introduced, as the model is adapted to 0.7.2 in update_ProbabilityGroup method*/

		final List<Element> runnableItemElements = HelperUtil.getXpathResult(rootElement, xpathBuffer.toString(),
				Element.class, AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element runnableItemElement : runnableItemElements) {


			final List<Element> deviationRunnableItemsList = HelperUtil.getXpathResult(runnableItemElement, "./items",
					Element.class);

			final Iterator<Element> deviationRunnableItemsListIterator = deviationRunnableItemsList.iterator();

			while (deviationRunnableItemsListIterator.hasNext()) {

				final Element deviationRunnableItemElement = deviationRunnableItemsListIterator.next();


				final List<Element> childRunnableItems = HelperUtil.getXpathResult(deviationRunnableItemElement,
						"./runnableItem", Element.class);

				if (childRunnableItems != null && !childRunnableItems.isEmpty()) {

					final Element childRunnableItem = childRunnableItems.get(0);

					/*- disassociating the runnableItem from its parent DeviationRunnableItem */

					deviationRunnableItemElement.removeContent(childRunnableItem);

					childRunnableItem.setName("items");

					runnableItemElement.removeContent(deviationRunnableItemElement);
					/*- now associate RunnableItem to the Group directly */
					runnableItemElement.addContent(childRunnableItem);

				} else {
					/*- this is the case where empty items tag is present (i.e. DeviationRunnableItem -> without RunnableItems */
					runnableItemElement.removeContent(deviationRunnableItemElement);
				}

				/*- DeviationRunnableItem is removed from metamodel -> RunnableItem which is present inside DeviationRunnableItem is directly associated inside Group
				 *  Due to the above reason : DeviationRunnableElement is removed from Group
				 * */
			}
		}
	}

	/**
	 * Migration of ProbabilityGroup:
	 *
	 * Based on changes introduced in 0.7.2, ProbabilityGroup is removed and its equivalent is
	 * "RunnableProbabilityGroup" (associated to Runnable elements)
	 *
	 * From 0.7.1 - ProbabilityGroup structure is as shown below:
	 *
	 * <pre>
	 *	ProbabilityGroup
	 *		- ProbabilityRunnableItem items[0-*]
	 *				- EInt probability[0-1]
	 *				- RunnableItem runnableItem[0-1]
	 * </pre>
	 *
	 * From 0.7.2 - RunnableProbabilitySwitch structure is as shown below
	 *
	 * <pre>
	 *	RunnableProbabilitySwitch
	 *		- ProbabilitySwitchEntry entries[0-*]
	 *				- EDouble probability[0-1]
	 *				- RunnableItem items[0-*]
	 * </pre>
	 *
	 * *
	 *
	 * @param rootElement
	 */

	private void updateProbabilityGroup(final Element rootElement) {


		final StringBuilder xpathBuffer = new StringBuilder();

		xpathBuffer.append("./swModel/runnables//runnableItems[@xsi:type=\"am:ProbabilityGroup\"]");
		xpathBuffer.append("|");
		xpathBuffer.append("./swModel/runnables//runnableItem[@xsi:type=\"am:ProbabilityGroup\"]");

		final List<Element> runnableItemElements = HelperUtil.getXpathResult(rootElement, xpathBuffer.toString(),
				Element.class, AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

		for (final Element runnableItemElement : runnableItemElements) {

			final Attribute typeAttribute = runnableItemElement.getAttribute("type", AmaltheaNamespaceRegistry.getGenericNamespace("xsi"));

			typeAttribute.setValue(
					"am:RunnableProbabilitySwitch"); /*-changing the type from ProbabilityGroup to RunnableProbabilitySwitch*/

			final List<Element> itemsElements = runnableItemElement.getChildren("items");

			for (final Element itemsElement : itemsElements) {
				itemsElement.setName("entries"); /*-changing the identifier name from items to entries*/

				final Element childRunnableItemElement = itemsElement.getChild("runnableItem");

				if (childRunnableItemElement != null) {
					childRunnableItemElement
							.setName("items"); /*-changing the identifier name from runnableItem to items*/
				}
			}
		}
	}
}