/**
 *                                                                            
 *  Copyright (c) 2011, 2016 - Loetz GmbH&Co.KG (69115 Heidelberg, Germany) 
 *                                                                            
 *  All rights reserved. This program and the accompanying materials           
 *  are made available under the terms of the Eclipse Public License 2.0        
 *  which accompanies this distribution, and is available at                  
 *  https://www.eclipse.org/legal/epl-2.0/                                 
 *                                 
 *  SPDX-License-Identifier: EPL-2.0                                 
 *                                                                            
 *  Contributors:                                                      
 * 	   Christophe Loetz (Loetz GmbH&Co.KG) - initial implementation
 * 
 */
package org.eclipse.osbp.utils.vaadin;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

import org.eclipse.e4.core.contexts.IEclipseContext;
import org.eclipse.osbp.core.api.persistence.IPersistenceService;
import org.eclipse.osbp.mondrian.api.IMondrianService;
import org.eclipse.osbp.ui.api.metadata.IDSLMetadataService;
import org.eclipse.osbp.ui.api.user.IUser;
import org.eclipse.osbp.xtext.datamart.common.olap.DerivedAxis;
import org.eclipse.osbp.xtext.datamart.common.olap.DerivedCell;
import org.eclipse.osbp.xtext.datamart.common.olap.DerivedCellSet;
import org.eclipse.osbp.xtext.datamart.common.olap.DerivedMember;
import org.eclipse.osbp.xtext.datamart.common.olap.DerivedPosition;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.vaadin.data.Item;
import com.vaadin.server.ClientConnector.DetachListener;
import com.vaadin.ui.Button;
import com.vaadin.ui.Component;
import com.vaadin.ui.TabSheet;
import com.vaadin.ui.Table;
import com.vaadin.ui.Table.RowHeaderMode;
import com.vaadin.ui.TextArea;
import com.vaadin.ui.VerticalLayout;
import com.vaadin.ui.Window;

import mondrian.olap4j.MondrianOlap4jDriver;
import mondrian.rolap.RolapConnection;

public class MDXDialog extends Window implements DetachListener { // NOSONAR
	private static final String MEMBER_TITLE = "member";
	/**
	 * 
	 */
	private static final long serialVersionUID = 3461161019240158996L;
	private static final Logger LOGGER = LoggerFactory.getLogger(MDXDialog.class);
	private TextArea input;
	private Button button;
	private Component tableLayout;
	private String messageText = "MDX Query";
	private String buttonText = "execute";
	private String areaText = "Statement";
	private String sampleText = "select Non Empty [Measures].[Salary] on columns,Non Empty [Employees].[Employee].Members on rows from Payroll";
	private transient IDSLMetadataService dslMetadataService;
	private transient RolapConnection connection;
	private transient IPersistenceService persistenceService;
	private transient IMondrianService mondrianService;
	private transient IUser user;
	private VerticalLayout subLayout;
	private ArrayList<Integer> coordinateSystem = new ArrayList<>();

	public MDXDialog(IEclipseContext eclipseContext) {
		super();
		addDetachListener(this);
		dslMetadataService = eclipseContext.get(IDSLMetadataService.class);
		persistenceService = eclipseContext.get(IPersistenceService.class);
		user = eclipseContext.get(IUser.class);
		mondrianService = eclipseContext.get(IMondrianService.class);

		setClosable(true);
		setModal(false);
		VerticalLayout subContent = new VerticalLayout();
		subContent.setMargin(true);
		setContent(subContent);
		setCaption(messageText);
		subContent.setSpacing(true);
		subLayout = new VerticalLayout();
		subContent.addComponent(subLayout);

		input = new TextArea(areaText);
		input.setRows(6);
		input.setWordwrap(true);
		input.setSizeFull();
		input.setValue(sampleText);
		input.setWidth("600px");
		input.setHeight("150px");

		subLayout.addComponent(input);
		button = new Button(buttonText);
		button.addClickListener(e -> executeQuery());
		subLayout.addComponent(button);
		center();
		connect();
	}

	@Override
	public void setLocale(Locale locale) {
		super.setLocale(locale);
		setCaption(dslMetadataService.translate(locale.toLanguageTag(), messageText));
	}

	private void connect() {
		if (connection == null) {
			LOGGER.debug("{}", "connect MDX");
			try {
				// for simplicity we only take the first entity used in a cube definition to establish connection
				connection = persistenceService.getMondrianConnection(mondrianService.getPersistenceUnit(),
						mondrianService.getPackageName());
			} catch (SQLException e) {
				LOGGER.error("{}", e);
			}
		}
	}

	private void disconnect() {
		LOGGER.debug("{}", "disconnect MDX");
		if (connection != null) {
			connection.close();
			connection = null;
		}
	}

	private void executeQuery() {
		LOGGER.debug("{}", "execute MDX");
		if (tableLayout != null) {
			subLayout.removeComponent(tableLayout);
		}
		RolapConnection rolapConnection = connection;
		Connection connection;
		// (JCD) : temporarily disabled to avoid errors with mondrian 4
//		try {
//			connection = new MondrianOlap4jDriver().connect(rolapConnection);
//			Statement statement = connection.createStatement();
//			ResultSet result = statement.executeQuery(input.getValue());
//		} catch (SQLException e) {
//			// TODO Auto-generated catch block
//			e.printStackTrace();
//		}
		DerivedCellSet cellSet = new DerivedCellSet(persistenceService.sendQuery(this.connection, input.getValue()),
				dslMetadataService, user);
		coordinateSystem.clear();
		for (int axis = 0; axis < cellSet.getAxes().size(); axis++) {
			coordinateSystem.add(0);
		}
		tableLayout = createTabSheet(cellSet, cellSet.getAxes().size());
		subLayout.addComponent(tableLayout);
	}

	private Component createTabSheet(DerivedCellSet cellSet, final Integer axisNo) {
		Component component = null;
		if (axisNo == 2) {
			component = createTable(cellSet);
		} else {
			Integer axis = axisNo - 1;
			TabSheet tabsheet = new TabSheet();
			tabsheet.setSizeFull();
			DerivedAxis tabAxis = cellSet.getAxes().get(axis);
			int tabNo = 0;
			for (DerivedPosition column : tabAxis.getPositions()) {
				String title = null;
				for (DerivedMember member : column.getMembers()) {
					if (title == null) {
						title = member.getCaption();
					} else {
						title += " / " + member.getCaption();
					}
				}
				coordinateSystem.set(axis, tabNo);
				component = createTabSheet(cellSet, axis);
				if (component != null) {
					component.setCaption(title);
					tabsheet.addComponent(component);
				}
				tabNo++;
			}
			component = tabsheet;
		}
		return component;
	}

	private Component createTable(DerivedCellSet cellSet) {
	    List<Integer> coordinate = new ArrayList<>(coordinateSystem);
		VerticalLayout container = new VerticalLayout();
		Table table = new Table();
		table.setImmediate(true);
		table.setMultiSelect(false);
		table.setSelectable(true);
		table.setRowHeaderMode(RowHeaderMode.HIDDEN);
		table.setSizeFull();
		container.addComponent(table);

		if(cellSet.getAxes().size() >= 2 && !cellSet.getAxes().get(1).getPositions().isEmpty()) {
			renderTable(cellSet, coordinate, table);
		}
		return container;
	}

	private void renderTable(DerivedCellSet cellSet, List<Integer> coordinate, Table table) {
		for (int memCnt = 0; memCnt < cellSet.getAxes().get(1).getPositions().iterator().next().getMembers()
				.size(); memCnt++) {
			String title = MEMBER_TITLE + memCnt;
			table.addContainerProperty(title, String.class, null);
		}

		for (DerivedPosition pos : cellSet.getAxes().get(0).getPositions()) {
			String title = null;
			for (DerivedMember member : pos.getMembers()) {
				if (title == null) {
					title = member.getCaption();
				} else {
					title += " " + member.getCaption();
				}
			}
			if (title != null) {
				table.addContainerProperty(title, Double.class, null);
			}
		}

		int rowsNo = 0;
		for (DerivedPosition rowsPos : cellSet.getAxes().get(1).getPositions()) {
			Object newItem = table.addItem();
			int memCnt = 0;
			for (DerivedMember member : rowsPos.getMembers()) {
				String coltitle = MEMBER_TITLE + memCnt;
				Item r = table.getItem(newItem);
				r.getItemProperty(coltitle).setValue(member.getUniqueName());
				memCnt++;
			}
			coordinate.set(1, rowsNo);
			int columnsNo = 0;
			for (DerivedPosition columnsPos : cellSet.getAxes().get(0).getPositions()) {
				coordinate.set(0, columnsNo);
				Object value = null;
				DerivedCell cell = cellSet.getCell(coordinate);
				if (cell != null) {
					if (cell.getValue() == null) {
						value = 0.0;
					} else {
						value = cell.getValue();
					}
				}
				String title = null;
				for (DerivedMember member : columnsPos.getMembers()) {
					if (title == null) {
						title = member.getCaption();
					} else {
						title += " " + member.getCaption();
					}
				}
				Item r = table.getItem(newItem);
				r.getItemProperty(title).setValue(value);
				columnsNo++;
			}
			rowsNo++;
		}
	}

	@Override
	public void detach(DetachEvent event) {
		disconnect();
	}
}