EDIT

/**

* Copyright (C) 2019 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.database.update;

import java.util.List;

import org.apache.logging.log4j.LogManager;import org.apache.logging.log4j.Logger;

import eu.etaxonomy.cdm.common.monitor.IProgressMonitor;

import eu.etaxonomy.cdm.database.DatabaseTypeEnum;

import eu.etaxonomy.cdm.database.ICdmDataSource;

/**

 * @author a.mueller

 * @since 24.07.2019

 *

 */

public class AllowNullUpdater

        extends AuditedSchemaUpdaterStepBase{

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

    private String columnName;

    private Datatype datatype;

    private Integer size;  //only required for MySQL

    public static AllowNullUpdater NewStringInstance(List<ISchemaUpdaterStep> stepList, String stepName,

            String tableName, String columnName, boolean includeAudTable){

        return new AllowNullUpdater(stepList, stepName, tableName, columnName, includeAudTable, Datatype.VARCHAR, 255);

    }

    public static AllowNullUpdater NewStringInstance(List<ISchemaUpdaterStep> stepList, String stepName, String tableName, String columnName,

            int size, boolean includeAudTable){

        return new AllowNullUpdater(stepList, stepName, tableName, columnName, includeAudTable, Datatype.VARCHAR, size);

    }

 // **************************************** Constructor ***************************************/

    protected AllowNullUpdater(List<ISchemaUpdaterStep> stepList, String stepName, String tableName, String columnName,

            boolean includeAudTable, Datatype datatype, Integer size) {

        super(stepList, stepName, tableName, includeAudTable);

        this.columnName = columnName;

        this.datatype = datatype;

        this.size = size;

    }

    @Override

    protected void invokeOnTable(String tableName, ICdmDataSource datasource,

            IProgressMonitor monitor, CaseType caseType, SchemaUpdateResult result) {

        try {

            DatabaseTypeEnum type = datasource.getDatabaseType();

            String updateQuery1;

            if (type.equals(DatabaseTypeEnum.SqlServer2005)){

                String message = "SQLServer column name changer syntax not yet tested. Table name: " + this.tableName + "; column name: " + columnName;

                monitor.warning(message);

                result.addWarning(message);

                updateQuery1 = "ALTER TABLE @tableName ALTER COLUMN @columnName @definition";

            }else if ( type.equals(DatabaseTypeEnum.MySQL)){

                //FIXME MySQL column name changer

                //logger.warn("Changing column name not yet supported for MySQL");

                updateQuery1 = "ALTER TABLE @tableName MODIFY @columnName @definition";

            }else if (type.equals(DatabaseTypeEnum.H2)){

                updateQuery1 = "ALTER TABLE @tableName ALTER COLUMN @columnName DROP NOT NULL";

            }else if ( type.equals(DatabaseTypeEnum.PostgreSQL) ){

                updateQuery1 = "ALTER TABLE @tableName ALTER COLUMN @columnName DROP NOT NULL";

            }else{

                String message = "Update step '" + this.getStepName() + "' is not supported by " + type.getName();

                monitor.warning(message);

                result.addError(message, getStepName() + ", ColumnNameChanger.invokeOnTable");

                return;

            }

            updateQuery1 = updateQuery1.replace("@tableName", tableName);

            updateQuery1 = updateQuery1.replace("@columnName", columnName);

            updateQuery1 = updateQuery1.replace("@definition", getDefinition(datasource));

            datasource.executeUpdate(updateQuery1);

            return;

        } catch (Exception e) {

            String message = e.getMessage();

            monitor.warning(message, e);

            logger.error(e);

            result.addException(e, message, getStepName() + ", ColumnNameChanger.invokeOnTable");

            return;

        }

    }

    private CharSequence getDefinition(ICdmDataSource datasource) {

        return datatype.format(datasource,size);

    }

}