package liquibase.ext.spatial.sqlgenerator;
   
   import liquibase.database.Database;
   import liquibase.database.core.DerbyDatabase;
   import liquibase.database.core.H2Database;
   import liquibase.exception.ValidationErrors;
   import liquibase.ext.spatial.statement.CreateSpatialIndexStatement;
   import liquibase.sql.Sql;
   import liquibase.sql.UnparsedSql;
  import liquibase.sqlgenerator.SqlGeneratorChain;
  import liquibase.structure.core.Table;
  
  /**
   * <code>CreateSpatialIndexGeneratorGeoDB</code> generates the SQL for creating a spatial index in
   * Apache Derby and H2.
   */
  public class CreateSpatialIndexGeneratorGeoDB extends AbstractCreateSpatialIndexGenerator {
     @Override
     public boolean supports(final CreateSpatialIndexStatement statement, final Database database) {
        return database instanceof DerbyDatabase || database instanceof H2Database;
     }
  
     /**
      * {@inheritDoc} Also ensures that the SRID is populated.
      */
     @Override
     public ValidationErrors validate(final CreateSpatialIndexStatement statement,
           final Database database, final SqlGeneratorChain sqlGeneratorChain) {
        final ValidationErrors validationErrors = super.validate(statement, database,
              sqlGeneratorChain);
        validationErrors.checkRequiredField("srid", statement.getSrid());
        return validationErrors;
     }
  
     /**
      * @see liquibase.sqlgenerator.SqlGenerator#generateSql(liquibase.statement.SqlStatement,
      *      liquibase.database.Database, liquibase.sqlgenerator.SqlGeneratorChain)
      */
     @Override
     public Sql[] generateSql(final CreateSpatialIndexStatement statement, final Database database,
           final SqlGeneratorChain sqlGeneratorChain) {
        final String catalogName = statement.getTableCatalogName();
        String schemaName = statement.getTableSchemaName();
        if (schemaName == null) {
           schemaName = database.getDefaultSchemaName();
        }
        final StringBuilder sql = new StringBuilder("CALL ");
        sql.append(schemaName).append(".CreateSpatialIndex(");
  
        // Add the schema name parameter.
        sql.append("'").append(schemaName).append("'");
        sql.append(", ");
  
        // Add the table name parameter.
        final String tableName = statement.getTableName();
        sql.append("'").append(tableName).append("'");
        sql.append(", ");
  
        // Add the column name parameter.
        final String columnName = statement.getColumns()[0];
        sql.append("'").append(columnName).append("'");
        sql.append(", ");
  
        // Add the SRID parameter.
        final int srid = statement.getSrid();
        sql.append("'").append(srid).append("'");
        sql.append(')');
        final Table hatboxTable = new Table().setName(database.correctObjectName(tableName
              + "_HATBOX", Table.class));
        hatboxTable.setSchema(catalogName, schemaName);
        final UnparsedSql spatialize = new UnparsedSql(sql.toString(), hatboxTable);
  
        return new Sql[] { spatialize };
     }
  }