EDIT

/**

 * Copyright (C) 2007 EDIT

 * European Distributed Institute of Taxonomy

 * http://www.e-taxonomy.eu

 *

 * The contents of this file are subject to the Mozilla Public License Version 1.1

 * See LICENSE.TXT at the top of this package for the full license terms.

 *

 * @author n.hoffmann

 * @version $Id: $

 */

package eu.etaxonomy.taxeditor.datasource;

import java.io.File;

import java.io.FileNotFoundException;

import java.util.ArrayList;

import java.util.List;

import org.eclipse.core.runtime.IPath;

import org.eclipse.ui.IMemento;

import org.eclipse.ui.XMLMemento;

import eu.etaxonomy.cdm.database.CdmDataSource;

import eu.etaxonomy.cdm.database.CdmPersistentDataSource;

import eu.etaxonomy.cdm.database.DataSourceNotFoundException;

import eu.etaxonomy.cdm.database.ICdmDataSource;

import eu.etaxonomy.cdm.model.name.NomenclaturalCode;

import eu.etaxonomy.taxeditor.model.MementoHelper;

import eu.etaxonomy.taxeditor.preference.PreferencesUtil;

import eu.etaxonomy.taxeditor.store.CdmStore;

import eu.etaxonomy.taxeditor.store.StoreUtil;

import eu.etaxonomy.taxeditor.store.internal.TaxeditorStorePlugin;

public class CdmDataSourceRepository{;

	/** Constant <code>TAG_DATASOURCE="tagDataSource"</code> */

	public static final String TAG_DATASOURCE = "tagDataSource";

	private static final String CURRENT_DATASOURCE = "currentDataSource";

	private static final String DEFAULT_DATASOURCE_STATE_FILENAME = "datasource.xml";

	private static final String DEFAULT_DATASOURCE_NAME = "cdm";

	private static ICdmDataSource currentDataSource;

	private static IMemento memento;

	private static String lastUsedDataSourceName;

	/**

	 * <p>Getter for the field <code>lastUsedDataSourceName</code>.</p>

	 *

	 * @return a {@link java.lang.String} object.

	 */

	public static String getLastUsedDataSourceName(){

		if(lastUsedDataSourceName == null){

			memento = readMemento();		

			lastUsedDataSourceName = memento != null ? memento.getString(CURRENT_DATASOURCE) : DEFAULT_DATASOURCE_NAME;

		}

		return lastUsedDataSourceName;

	}

	/**

	 * <p>delete</p>

	 *

	 * @param dataSource a {@link eu.etaxonomy.cdm.database.CdmPersistentDataSource} object.

	 * @return a boolean.

	 */

	public static boolean delete(CdmPersistentDataSource dataSource) {

		CdmPersistentDataSource.delete(dataSource);

		return true;

	}

	/**

	 * <p>getAll</p>

	 *

	 * @return a {@link java.util.List} object.

	 */

	public static List<ICdmDataSource> getAll() {

		List<ICdmDataSource> dataSources = new ArrayList<ICdmDataSource>();

		for(ICdmDataSource dataSource : CdmPersistentDataSource.getAllDataSources()){

			try {

				dataSources.add(CdmPersistentDataSource.NewInstance(dataSource.getName()));

			} catch (DataSourceNotFoundException e) {

				StoreUtil.error(CdmDataSourceRepository.class, "Could not find dataSource", e);

			}

		}

		// TODO sort by database name

		return dataSources;

	}

	/**

	 * <p>getDataSource</p>

	 *

	 * @param name a {@link java.lang.String} object.

	 * @return a {@link eu.etaxonomy.cdm.database.ICdmDataSource} object.

	 */

	public static ICdmDataSource getDataSource(String name){

		for(ICdmDataSource dataSource : CdmPersistentDataSource.getAllDataSources()){

			try {

				if(dataSource.getName().equals(name)){

					return CdmPersistentDataSource.NewInstance(dataSource.getName());

				}

			} catch (DataSourceNotFoundException e) {

				StoreUtil.error(CdmDataSourceRepository.class, "Could not find dataSource", e);

			}

		}

		return null;

	}

	/**

	 * <p>Getter for the field <code>currentDataSource</code>.</p>

	 *

	 * @return a {@link eu.etaxonomy.cdm.database.ICdmDataSource} object.

	 */

	public static ICdmDataSource getCurrentDataSource() {

		if (currentDataSource == null) {

			try {

				currentDataSource = CdmPersistentDataSource.NewInstance(getLastUsedDataSourceName());

			} catch (DataSourceNotFoundException e) {

				// fallback creates a new default

				ICdmDataSource h2DataSource = CdmDataSource.NewH2EmbeddedInstance(

						DEFAULT_DATASOURCE_NAME, "sa", "", PreferencesUtil.getPreferredNomenclaturalCode());

				save(h2DataSource.getName(), h2DataSource);

				setCurrentDataSource(h2DataSource);

			}

		}

		return currentDataSource;

	}

	/**

	 * <p>Setter for the field <code>currentDataSource</code>.</p>

	 *

	 * @param dataSource a {@link eu.etaxonomy.cdm.database.ICdmDataSource} object.

	 * @return a boolean.

	 */

	public static boolean setCurrentDataSource(ICdmDataSource dataSource) {

		currentDataSource = dataSource;

		NomenclaturalCode dataSourceNomenclaturalCode = dataSource.getNomenclaturalCode();

		NomenclaturalCode applicationNomenclaturalCode = PreferencesUtil.getPreferredNomenclaturalCode();

		if( dataSourceNomenclaturalCode != null && ! dataSourceNomenclaturalCode.equals(applicationNomenclaturalCode)){

			PreferencesUtil.setPreferredNomenclaturalCode(dataSourceNomenclaturalCode);

			StoreUtil.informationDialog("Nomenclatural Code Change", "The Datasource that was just " +

					"loaded has a different nomenclatural code than the one stored in Preferences. " +

					"The nomenclatural code was changed in the application.");

		}

		return true;

	}	

	/**

	 * <p>changeDataSource</p>

	 *

	 * @param dataSource a {@link eu.etaxonomy.cdm.database.ICdmDataSource} object.

	 * @return a boolean.

	 */

	public static boolean changeDataSource(final ICdmDataSource dataSource) {

		saveAsCurrentDatabaseToMemento(dataSource);

		CdmStore.connect(dataSource);

		return true;

	}

	/**

	 * <p>save</p>

	 *

	 * @param dataSource a {@link eu.etaxonomy.cdm.database.ICdmDataSource} object.

	 * @param strDataSourceName a {@link java.lang.String} object.

	 * @return a {@link eu.etaxonomy.cdm.database.CdmPersistentDataSource} object.

	 */

	public static CdmPersistentDataSource save(String strDataSourceName, ICdmDataSource dataSource) {

		return CdmPersistentDataSource.save(strDataSourceName, dataSource);

	}

	/**

	 * <p>update</p>

	 *

	 * @param strDataSourceName a {@link java.lang.String} object.

	 * @param dataSource a {@link eu.etaxonomy.cdm.database.ICdmDataSource} object.

	 * @return a {@link eu.etaxonomy.cdm.database.CdmPersistentDataSource} object.

	 */

	public static CdmPersistentDataSource update(String strDataSourceName, ICdmDataSource dataSource){

		try {

			return CdmPersistentDataSource.update(strDataSourceName, dataSource);

		} catch (Exception e) {

			StoreUtil.error(CdmDataSourceRepository.class, "Error updating datasource", e);

		}

		return null;

	}

	/*********************************************************

	 * Memento Handling										 *

	 *********************************************************/

	private static void saveAsCurrentDatabaseToMemento(ICdmDataSource dataSource){

		if(memento == null)

			memento = readMemento();

		memento.putString(CURRENT_DATASOURCE, dataSource.getName());

		saveMementoToFile(memento);

	}

	/*

	 * Answer the workbench state file.

	 */

	private static File getDataSourceStateFile() {

		IPath path = TaxeditorStorePlugin.getDefault().getStateLocation();

		if (path == null) {

			return null;

		}

		path = path.append(DEFAULT_DATASOURCE_STATE_FILENAME);

		return path.toFile();

	}

	private static IMemento readMemento(){

		try {

			return MementoHelper.readMementoFromFile(getDataSourceStateFile());

		} catch (FileNotFoundException e) {

			return initializeMemento();

		}

	}

	private static IMemento initializeMemento() {

		XMLMemento memento = XMLMemento.createWriteRoot(TAG_DATASOURCE);

		memento.putString(CURRENT_DATASOURCE, DEFAULT_DATASOURCE_NAME);

		saveMementoToFile(memento);

		return readMemento();

	}

	/*

	 * Save the workbench UI in a persistence file.

	 */

	private static IMemento saveMementoToFile(IMemento memento) {

		return MementoHelper.saveMementoToFile(memento, getDataSourceStateFile());

	}	

}