# PostgreSQLDatabaseSettings.java

    package org.codefilarete.stalactite.sql;

    import java.util.Collections;

    import org.codefilarete.stalactite.engine.DatabaseVendorSettings;
    import org.codefilarete.stalactite.engine.SQLOperationsFactories;
    import org.codefilarete.stalactite.engine.SQLOperationsFactoriesBuilder;
    import org.codefilarete.stalactite.mapping.id.sequence.DatabaseSequenceSelector;
    import org.codefilarete.stalactite.sql.GeneratedKeysReaderFactory.DefaultGeneratedKeysReaderFactory;
    import org.codefilarete.stalactite.sql.PostgreSQLDialectResolver.PostgreSQLDatabaseSignet;
    import org.codefilarete.stalactite.sql.ddl.DDLSequenceGenerator;
    import org.codefilarete.stalactite.sql.ddl.DDLTableGenerator;
    import org.codefilarete.stalactite.sql.ddl.SqlTypeRegistry;
    import org.codefilarete.stalactite.sql.ddl.structure.Column;
    import org.codefilarete.stalactite.sql.ddl.structure.Sequence;
    import org.codefilarete.stalactite.sql.statement.DMLGenerator;
    import org.codefilarete.stalactite.sql.statement.ReadOperationFactory;
    import org.codefilarete.stalactite.sql.statement.WriteOperationFactory;
    import org.codefilarete.stalactite.sql.statement.binder.ParameterBinder;
    import org.codefilarete.stalactite.sql.statement.binder.ParameterBinderIndex;
    import org.codefilarete.stalactite.sql.statement.binder.PostgreSQLParameterBinderRegistry;
    import org.codefilarete.stalactite.sql.statement.binder.PostgreSQLTypeMapping;
    import org.codefilarete.tool.VisibleForTesting;
    import org.codefilarete.tool.collection.CaseInsensitiveSet;

    /**
     *
     * @author Guillaume Mary
     */
    public class PostgreSQLDatabaseSettings extends DatabaseVendorSettings {

    	/**
    	 * PostgreSQL keywords, took from <a href="https://www.postgresql.org/docs/current/sql-keywords-appendix.html">PostgreSQL documentation</a>
    	 * and selecting only "reserved" ones by PostgreSQL (the ones that require to be escaped)
    	 */
    	public static final String[] KEYWORDS = new String[] {
    			"ALL", "ANALYSE", "ANALYZE", "AND", "ANY", "ASC", "ASYMMETRIC",
    			"BOTH",
    			"CASE", "CAST", "CHECK", "COLLATE", "COLUMN", "CONSTRAINT", "CURRENT_CATALOG", "CURRENT_DATE", "CURRENT_ROLE", "CURRENT_TIME", "CURRENT_TIMESTAMP", "CURRENT_USER",
    			"DEFAULT", "DEFERRABLE", "DESC", "DISTINCT", "DO",
    			"ELSE", "END",
    			"FALSE", "FOREIGN",
    			"IN", "INITIALLY",
    			"LATERAL", "LEADING", "LOCALTIME", "LOCALTIMESTAMP",
    			"NOT", "NULL",
    			"ONLY", "OR",
    			"PLACING", "PRIMARY",
    			"REFERENCES",
    			"SELECT", "SESSION_USER", "SOME", "SYMMETRIC", "SYSTEM_USER",
    			"TABLE", "THEN", "TRAILING", "TRUE",
    			"UNIQUE", "USER", "USING",
    			"VARIADIC",
    			"WHEN",
    	};

    	public static final PostgreSQLDatabaseSettings POSTGRESQL_9_6 = new PostgreSQLDatabaseSettings();

    	private PostgreSQLDatabaseSettings() {
    		this(new PostgreSQLSQLOperationsFactoriesBuilder(), new PostgreSQLParameterBinderRegistry());
    	}

    	private PostgreSQLDatabaseSettings(PostgreSQLSQLOperationsFactoriesBuilder sqlOperationsFactoriesBuilder, PostgreSQLParameterBinderRegistry parameterBinderRegistry) {
    		super(new PostgreSQLDatabaseSignet(9, 6),
    				Collections.unmodifiableSet(new CaseInsensitiveSet(KEYWORDS)),
    				'`',
    				new PostgreSQLTypeMapping(),
    				parameterBinderRegistry,
    				sqlOperationsFactoriesBuilder,
    				new DefaultGeneratedKeysReaderFactory(parameterBinderRegistry),
    				1000,
    				true);
    	}

    	private static class PostgreSQLSQLOperationsFactoriesBuilder implements SQLOperationsFactoriesBuilder {

    		private final ReadOperationFactory readOperationFactory;
    		private final WriteOperationFactory writeOperationFactory;

    		private PostgreSQLSQLOperationsFactoriesBuilder() {
    			this.readOperationFactory = new ReadOperationFactory();
    			this.writeOperationFactory = new WriteOperationFactory();
    		}

    		private ReadOperationFactory getReadOperationFactory() {
    			return readOperationFactory;
    		}

    		private WriteOperationFactory getWriteOperationFactory() {
    			return writeOperationFactory;
    		}

    		@Override
    		public SQLOperationsFactories build(ParameterBinderIndex<Column, ParameterBinder> parameterBinders, DMLNameProviderFactory dmlNameProviderFactory, SqlTypeRegistry sqlTypeRegistry) {
    			DMLGenerator dmlGenerator = new DMLGenerator(parameterBinders, DMLGenerator.NoopSorter.INSTANCE, dmlNameProviderFactory);
    			PostgreSQLDDLTableGenerator ddlTableGenerator = new PostgreSQLDDLTableGenerator(sqlTypeRegistry, dmlNameProviderFactory);
    			DDLSequenceGenerator ddlSequenceGenerator = new DDLSequenceGenerator(dmlNameProviderFactory);
    			return new SQLOperationsFactories(writeOperationFactory, readOperationFactory, dmlGenerator, ddlTableGenerator, ddlSequenceGenerator,
    					new PostgreSQLSequenceSelectorFactory(readOperationFactory));
    		}
    	}

    	public static class PostgreSQLDDLTableGenerator extends DDLTableGenerator {

    		public PostgreSQLDDLTableGenerator(SqlTypeRegistry typeMapping, DMLNameProviderFactory dmlNameProviderFactory) {
    			super(typeMapping, dmlNameProviderFactory);
    		}

    		@Override
    		protected String getSqlType(Column column) {
    			String sqlType;
    			if (column.isAutoGenerated()) {
    				sqlType = "BIGSERIAL";
    			} else {
    				sqlType = super.getSqlType(column);
    			}
    			return sqlType;
    		}
    	}

    	@VisibleForTesting
    	static class PostgreSQLSequenceSelectorFactory implements DatabaseSequenceSelectorFactory {

    		private final ReadOperationFactory readOperationFactory;

    		private PostgreSQLSequenceSelectorFactory(ReadOperationFactory readOperationFactory) {
    			this.readOperationFactory = readOperationFactory;
    		}

    		@Override
    		public DatabaseSequenceSelector create(Sequence databaseSequence, ConnectionProvider connectionProvider) {
    			return new DatabaseSequenceSelector(databaseSequence, "select nextval('" + databaseSequence.getAbsoluteName() + "')", readOperationFactory, connectionProvider);
    		}
    	}
    }