EDIT

/**

* Copyright (C) 2009 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.

*/

package eu.etaxonomy.cdm.io.stream.mapping;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Map.Entry;

import java.util.Set;

import org.apache.log4j.Logger;

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.io.stream.mapping.IImportMapping.CdmKey;

import eu.etaxonomy.cdm.model.agent.Person;

import eu.etaxonomy.cdm.model.agent.Team;

import eu.etaxonomy.cdm.model.common.IdentifiableEntity;

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

import eu.etaxonomy.cdm.model.reference.Reference;

import eu.etaxonomy.cdm.model.taxon.Synonym;

import eu.etaxonomy.cdm.model.taxon.Taxon;

/**

 * TODO inwork, currently it works with H2

 * @author a.mueller

 * @since 22.03.2012

 *

 */

public class DatabaseMapping implements IImportMapping {

    private static final Logger logger = Logger.getLogger(DatabaseMapping.class);

	private static final String DATABASE_INTERNAL_IMPORT_MAPPING = "_internalImportMapping";

	protected static final String TABLE_IMPORT_MAPPING  = "importmapping";

	private static final String COL_TASK_ID = "task_id";

	private static final String COL_SOURCE_NS = "source_namespace";

	private static final String COL_SOURCE_ID = "source_id";

	private static final String COL_DEST_NS = "destination_namespace";

	private static final String COL_DEST_ID = "destination_id";

    private static final int SOURCE_KEY_LENGTH = 255;

	private ICdmDataSource datasource;

	private final String mappingId;

	private final Map<String, Class> shortCuts = new HashMap<>();

	private final Map<Class, String> reverseShortCuts = new HashMap<>();

	@Override

	public void putMapping(String namespace, Integer sourceKey, IdentifiableEntity destinationObject){

		putMapping(namespace, String.valueOf(sourceKey), destinationObject);

	}

    public DatabaseMapping(String mappingId) {

        this(mappingId, null);

    }

	/**

	 * @param database

	 */

	public DatabaseMapping(String mappingId, String file) {

		super();

		initDatasource(file);

		this.mappingId = mappingId;

	}

	@Override

	public void putMapping(String namespace, String sourceKey, IdentifiableEntity destinationObject){

		CdmKey<IdentifiableEntity<?>> cdmKey = new CdmKey<>(destinationObject);

		putMapping(namespace, sourceKey, cdmKey);

	}

	public void putMapping(String namespace, String sourceKey, CdmKey<IdentifiableEntity<?>> cdmKey) {

		try {

		    String normalizedKey = normalizeKey(sourceKey);

			deleteExistingMapping(namespace, sourceKey);

			persistNotExistingMapping(namespace, normalizedKey, cdmKey);

		} catch (SQLException e) {

			throw new RuntimeException(e);

		}

	}

	private int persistNotExistingMapping(String sourceNamespace, String normalizedKey, CdmKey<IdentifiableEntity<?>> cdmKey) throws SQLException {

		//cdm namespace

		String clazz = getCdmClassStr(cdmKey.clazz);

		//insert

		String insertMappingSql = " INSERT INTO %s (%s, %s, %s, %s, %s)" +

			" VALUES ('%s','%s','%s','%s','%s')";

		insertMappingSql = String.format(insertMappingSql,

				TABLE_IMPORT_MAPPING, COL_TASK_ID, COL_SOURCE_NS, COL_SOURCE_ID, COL_DEST_NS, COL_DEST_ID,

				this.mappingId, sourceNamespace, normalizedKey, clazz, cdmKey.id);

		return this.datasource.executeUpdate(insertMappingSql);

	}

	/**

	 * @param cdmKey

	 * @return

	 */

	private String getCdmClassStr(Class cdmClass) {

		String clazz = reverseShortCuts.get(cdmClass);

		if (clazz == null){

			clazz = cdmClass.getCanonicalName();

		}

		return clazz;

	}

	private int deleteExistingMapping(String sourceNamespace, String sourceId) throws SQLException {

	    String normalizedKey = normalizeKey(sourceId);

		String deleteMappingSql = " DELETE FROM %s WHERE %s = '%s' AND %s = '%s' AND %s = '%s'";

		deleteMappingSql = String.format(deleteMappingSql,TABLE_IMPORT_MAPPING, COL_TASK_ID, this.mappingId, COL_SOURCE_NS, sourceNamespace, COL_SOURCE_ID, normalizedKey);

		return this.datasource.executeUpdate(deleteMappingSql);

	}

	private int deleteAll() throws SQLException {

		String deleteMappingSql = " DELETE FROM %s WHERE %s = '%s' ";

		deleteMappingSql = String.format(deleteMappingSql,TABLE_IMPORT_MAPPING, COL_TASK_ID, this.mappingId);

		return this.datasource.executeUpdate(deleteMappingSql);

	}

	public int size() throws SQLException {

		String sql = " SELECT count(*) as n FROM %s WHERE %s = '%s' ";

		sql = String.format(sql,TABLE_IMPORT_MAPPING, COL_TASK_ID, this.mappingId);

		ResultSet rs = this.datasource.executeQuery(sql);

		rs.next();

		return rs.getInt("n");

	}

	@Override

	public Set<CdmKey> get(String sourceNamespace, String sourceId) {

		Set<CdmKey> result = new HashSet<>();

		String normalizedKey = normalizeKey(sourceId);

		String selectMappingSql = " SELECT %s, %s FROM %s" +

				" WHERE %s = '%s' AND %s = '%s' AND %s = '%s' ";

		selectMappingSql = String.format(selectMappingSql,

				COL_DEST_NS, COL_DEST_ID, TABLE_IMPORT_MAPPING,

				COL_TASK_ID, this.mappingId, COL_SOURCE_NS, sourceNamespace,

				COL_SOURCE_ID , normalizedKey);

		try {

			ResultSet rs = this.datasource.executeQuery(selectMappingSql);

			while (rs.next()){

				String clazzStr = rs.getString(COL_DEST_NS);

				Object id = rs.getObject(COL_DEST_ID);

				if (id == null){

					throw new RuntimeException("Destination id for import mapping is 'null'");

				}

				Class<?> clazz = getCdmClass(clazzStr);

				CdmKey<?> key = new CdmKey<>(clazz, Integer.valueOf(String.valueOf(id)));

				result.add(key);

			}

		} catch (NumberFormatException e) {

			throw new RuntimeException(e);

		} catch (SQLException e) {

			throw new RuntimeException(e);

		} catch (ClassNotFoundException e) {

			throw new RuntimeException(e);

		}

		return result;

	}

	@Override

    public boolean exists(String sourceNamespace, String sourceId, Class<?> destinationClass){

		String selectMappingSql = " SELECT count(*) as n FROM %s" +

			" WHERE %s = '%s' AND %s = '%s' AND %s = '%s' AND %s = '%s' ";

		String cdmClass = getCdmClassStr(destinationClass);

		String normalizedKey = normalizeKey(sourceId);

		selectMappingSql = String.format(selectMappingSql,

			TABLE_IMPORT_MAPPING, COL_TASK_ID, this.mappingId,

			COL_SOURCE_NS, sourceNamespace, COL_SOURCE_ID , normalizedKey, COL_DEST_NS, cdmClass);

		try {

			ResultSet rs = this.datasource.executeQuery(selectMappingSql);

			rs.next();

			int n = rs.getInt("n");

			return n > 0;

		} catch (SQLException e) {

			throw new RuntimeException(e);

		}

	}

    /**

     * Normalizes the key coming from the DwCA File.

     * This includes handling ' and keys with length > 255

     * @param sourceKey

     * @return

     */

    private String normalizeKey(String key) {

        if (key == null){

            return null;

        }

        String result = key.replace("'", "''");

        if (result.length() > SOURCE_KEY_LENGTH){

            //TODO better use MD5 hash or similar

            logger.info("Source key was truncated: " + key);

            result = result.substring(0, SOURCE_KEY_LENGTH);

        }

        return result;

    }

	@Override

	public InMemoryMapping getPartialMapping( Map<String, Set<String>> namespacedSourceKeys) {

		InMemoryMapping partialMapping = new InMemoryMapping();

		for (Entry<String,Set<String>> entry  : namespacedSourceKeys.entrySet()){

			String namespace = entry.getKey();

			for (String sourceKey : entry.getValue() ){

			    String normalizedKey = normalizeKey(sourceKey);

				Set<CdmKey> destObjects = this.get(namespace, normalizedKey);

				for (CdmKey cdmKey : destObjects){

					partialMapping.putMapping(namespace, normalizedKey, cdmKey);

				}

			}

		}

		return partialMapping;

	}

	@Override

	public void finish() {

		try {

			int count = size();

			deleteAll();

			logger.info("Finalize database mapping " +  count +  ": " + size());

		} catch (SQLException e) {

			throw new RuntimeException();

		}

	}

	/**

	 * @param clazzStr

	 * @return

	 * @throws ClassNotFoundException

	 */

	private Class<?> getCdmClass(String clazzStr) throws ClassNotFoundException {

		Class<?> clazz = shortCuts.get(clazzStr);

		if (clazz == null){

			clazz = Class.forName(clazzStr);

		}

		return clazz;

	}

	private void initDatasource(String file) {

		getDatabase(file);

		shortCuts.put("TaxonName", TaxonName.class);

		shortCuts.put("Taxon", Taxon.class);

		shortCuts.put("Synonym", Synonym.class);

		shortCuts.put("Reference", Reference.class);

		shortCuts.put("Team", Team.class);

		shortCuts.put("Person", Person.class);

		//reverse

		for (String key :shortCuts.keySet()){

			reverseShortCuts.put(shortCuts.get(key), key);

		}

	}

	public ICdmDataSource getDatabase(){

	    return getDatabase(null);

	}

	public ICdmDataSource getDatabase(String path){

		try {

			try {

			    if (path == null){

			        datasource = CdmPersistentDataSource.NewInstance(DATABASE_INTERNAL_IMPORT_MAPPING);

			    }else{

			        makeDatasource(path);

			    }

			} catch (DataSourceNotFoundException e) {

				makeDatasource(path);

				CdmPersistentDataSource.save(DATABASE_INTERNAL_IMPORT_MAPPING, datasource);

			}

			datasource.executeQuery("SELECT * FROM " + TABLE_IMPORT_MAPPING);

		} catch (SQLException e) {

			//create database structure

		    try {

				String strCreateTable = "CREATE TABLE IF NOT EXISTS %s (";

				strCreateTable += "%s nvarchar(36) NOT NULL,";

				strCreateTable += "%s nvarchar(100) NOT NULL,";

				strCreateTable += "%s nvarchar(" + SOURCE_KEY_LENGTH + ") NOT NULL,";

				strCreateTable += "%s nvarchar(100) NOT NULL,";

				strCreateTable += "destination_id nvarchar(50) NOT NULL,";

				strCreateTable += "PRIMARY KEY (task_id, source_namespace, source_id)";

				strCreateTable += ") ";

				strCreateTable = String.format(strCreateTable, TABLE_IMPORT_MAPPING, COL_TASK_ID, COL_SOURCE_NS, COL_SOURCE_ID, COL_DEST_NS, COL_DEST_ID);

				datasource.executeUpdate(strCreateTable);

				logger.warn("Mapping database structure created");

			} catch (SQLException e1) {

				e1.printStackTrace();

				throw new RuntimeException(e1);

			}

		}

		return datasource;

	}

    /**

     * @param path

     */

    private void makeDatasource(String path) {

        datasource = CdmDataSource.NewH2EmbeddedInstance("_tmpMapping", "a", "b", path);

    }

}