//$Id: MySQLDialect.java,v 1.38 2005/09/02 18:32:21 oneovthafew Exp $
package org.hibernate.dialect;

import java.sql.Types;

import org.hibernate.Hibernate;
import org.hibernate.cfg.Environment;
import org.hibernate.dialect.function.NoArgSQLFunction;
import org.hibernate.dialect.function.StandardSQLFunction;
import org.hibernate.util.StringHelper;

/**
 * An SQL dialect for MySQL.
 * @author Gavin King
 */
public class MySQLDialect extends Dialect {

	public MySQLDialect() {
		super();
		registerColumnType( Types.BIT, "bit" );
		registerColumnType( Types.BIGINT, "bigint" );
		registerColumnType( Types.SMALLINT, "smallint" );
		registerColumnType( Types.TINYINT, "tinyint" );
		registerColumnType( Types.INTEGER, "integer" );
		registerColumnType( Types.CHAR, "char(1)" );
		registerColumnType( Types.VARCHAR, "longtext" );
		registerColumnType( Types.VARCHAR, 16777215, "mediumtext" );
		registerColumnType( Types.VARCHAR, 65535, "text" );
		registerColumnType( Types.VARCHAR, 255, "varchar($l)" );
		registerColumnType( Types.FLOAT, "float" );
		registerColumnType( Types.DOUBLE, "double precision" );
		registerColumnType( Types.DATE, "date" );
		registerColumnType( Types.TIME, "time" );
		registerColumnType( Types.TIMESTAMP, "datetime" );
		registerColumnType( Types.VARBINARY, "longblob" );
		registerColumnType( Types.VARBINARY, 16777215, "mediumblob" );
		registerColumnType( Types.VARBINARY, 65535, "blob" );
		registerColumnType( Types.VARBINARY, 255, "tinyblob" );
		registerColumnType( Types.NUMERIC, "numeric($p,$s)" );
		registerColumnType( Types.BLOB, "longblob" );
		registerColumnType( Types.BLOB, 16777215, "mediumblob" );
		registerColumnType( Types.BLOB, 65535, "blob" );
		registerColumnType( Types.CLOB, "longtext" );
		registerColumnType( Types.CLOB, 16777215, "mediumtext" );
		registerColumnType( Types.CLOB, 65535, "text" );

		registerFunction("ascii", new StandardSQLFunction("ascii", Hibernate.INTEGER) );
		registerFunction("bin", new StandardSQLFunction("bin", Hibernate.STRING) );
		registerFunction("char_length", new StandardSQLFunction("char_length", Hibernate.LONG) );
		registerFunction("character_length", new StandardSQLFunction("character_length", Hibernate.LONG) );
		registerFunction("lcase", new StandardSQLFunction("lcase") );
		registerFunction("lower", new StandardSQLFunction("lower") );
		registerFunction("length", new StandardSQLFunction("length", Hibernate.LONG) );
		registerFunction("ltrim", new StandardSQLFunction("ltrim") );
		registerFunction("ord", new StandardSQLFunction("ord", Hibernate.INTEGER) );
		registerFunction("quote", new StandardSQLFunction("quote") );
		registerFunction("reverse", new StandardSQLFunction("reverse") );
		registerFunction("rtrim", new StandardSQLFunction("rtrim") );
		registerFunction("soundex", new StandardSQLFunction("soundex") );
		registerFunction("space", new StandardSQLFunction("space", Hibernate.STRING) );
		registerFunction("ucase", new StandardSQLFunction("ucase") );
		registerFunction("upper", new StandardSQLFunction("upper") );
		registerFunction("unhex", new StandardSQLFunction("unhex", Hibernate.STRING) );

		registerFunction("abs", new StandardSQLFunction("abs") );
		registerFunction("sign", new StandardSQLFunction("sign", Hibernate.INTEGER) );

		registerFunction("acos", new StandardSQLFunction("acos", Hibernate.DOUBLE) );
		registerFunction("asin", new StandardSQLFunction("asin", Hibernate.DOUBLE) );
		registerFunction("atan", new StandardSQLFunction("atan", Hibernate.DOUBLE) );
		registerFunction("cos", new StandardSQLFunction("cos", Hibernate.DOUBLE) );
		registerFunction("cot", new StandardSQLFunction("cot", Hibernate.DOUBLE) );
		registerFunction("crc32", new StandardSQLFunction("crc32", Hibernate.LONG) );
		registerFunction("exp", new StandardSQLFunction("exp", Hibernate.DOUBLE) );
		registerFunction("ln", new StandardSQLFunction("ln", Hibernate.DOUBLE) );
		registerFunction("log", new StandardSQLFunction("log", Hibernate.DOUBLE) );
		registerFunction("log2", new StandardSQLFunction("log2", Hibernate.DOUBLE) );
		registerFunction("log10", new StandardSQLFunction("log10", Hibernate.DOUBLE) );
		registerFunction("pi", new NoArgSQLFunction("pi", Hibernate.DOUBLE) );
		registerFunction("rand", new NoArgSQLFunction("rand", Hibernate.DOUBLE) );
		registerFunction("sin", new StandardSQLFunction("sin", Hibernate.DOUBLE) );
		registerFunction("sqrt", new StandardSQLFunction("sqrt", Hibernate.DOUBLE) );
		registerFunction("tan", new StandardSQLFunction("tan", Hibernate.DOUBLE) );

		registerFunction("radians", new StandardSQLFunction("radians", Hibernate.DOUBLE) );
		registerFunction("degrees", new StandardSQLFunction("degrees", Hibernate.DOUBLE) );

		registerFunction("ceiling", new StandardSQLFunction("ceiling", Hibernate.INTEGER) );
		registerFunction("ceil", new StandardSQLFunction("ceil", Hibernate.INTEGER) );
		registerFunction("floor", new StandardSQLFunction("floor", Hibernate.INTEGER) );
		registerFunction("round", new StandardSQLFunction("round", Hibernate.INTEGER) );

		registerFunction("datediff", new StandardSQLFunction("datediff", Hibernate.INTEGER) );
		registerFunction("timediff", new StandardSQLFunction("timediff", Hibernate.TIME) );
		registerFunction("date_format", new StandardSQLFunction("date_format", Hibernate.STRING) );

		registerFunction("curdate", new NoArgSQLFunction("curdate", Hibernate.DATE) );
		registerFunction("curtime", new NoArgSQLFunction("curtime", Hibernate.TIME) );
		registerFunction("current_date", new NoArgSQLFunction("current_date", Hibernate.DATE, false) );
		registerFunction("current_time", new NoArgSQLFunction("current_time", Hibernate.TIME, false) );
		registerFunction("current_timestamp", new NoArgSQLFunction("current_timestamp", Hibernate.TIMESTAMP, false) );
		registerFunction("date", new StandardSQLFunction("date", Hibernate.DATE) );
		registerFunction("day", new StandardSQLFunction("day", Hibernate.INTEGER) );
		registerFunction("dayofmonth", new StandardSQLFunction("dayofmonth", Hibernate.INTEGER) );
		registerFunction("dayname", new StandardSQLFunction("dayname", Hibernate.STRING) );
		registerFunction("dayofweek", new StandardSQLFunction("dayofweek", Hibernate.INTEGER) );
		registerFunction("dayofyear", new StandardSQLFunction("dayofyear", Hibernate.INTEGER) );
		registerFunction("from_days", new StandardSQLFunction("from_days", Hibernate.DATE) );
		registerFunction("from_unixtime", new StandardSQLFunction("from_unixtime", Hibernate.TIMESTAMP) );
		registerFunction("hour", new StandardSQLFunction("hour", Hibernate.INTEGER) );
		registerFunction("last_day", new StandardSQLFunction("last_day", Hibernate.DATE) );
		registerFunction("localtime", new NoArgSQLFunction("localtime", Hibernate.TIMESTAMP) );
		registerFunction("localtimestamp", new NoArgSQLFunction("localtimestamp", Hibernate.TIMESTAMP) );
		registerFunction("microseconds", new StandardSQLFunction("microseconds", Hibernate.INTEGER) );
		registerFunction("minute", new StandardSQLFunction("minute", Hibernate.INTEGER) );
		registerFunction("month", new StandardSQLFunction("month", Hibernate.INTEGER) );
		registerFunction("monthname", new StandardSQLFunction("monthname", Hibernate.STRING) );
		registerFunction("now", new NoArgSQLFunction("now", Hibernate.TIMESTAMP) );
		registerFunction("quarter", new StandardSQLFunction("quarter", Hibernate.INTEGER) );
		registerFunction("second", new StandardSQLFunction("second", Hibernate.INTEGER) );
		registerFunction("sec_to_time", new StandardSQLFunction("sec_to_time", Hibernate.TIME) );
		registerFunction("sysdate", new NoArgSQLFunction("sysdate", Hibernate.TIMESTAMP) );
		registerFunction("time", new StandardSQLFunction("time", Hibernate.TIME) );
		registerFunction("timestamp", new StandardSQLFunction("timestamp", Hibernate.TIMESTAMP) );
		registerFunction("time_to_sec", new StandardSQLFunction("time_to_sec", Hibernate.INTEGER) );
		registerFunction("to_days", new StandardSQLFunction("to_days", Hibernate.LONG) );
		registerFunction("unix_timestamp", new StandardSQLFunction("unix_timestamp", Hibernate.LONG) );
		registerFunction("utc_date", new NoArgSQLFunction("utc_date", Hibernate.STRING) );
		registerFunction("utc_time", new NoArgSQLFunction("utc_time", Hibernate.STRING) );
		registerFunction("utc_timestamp", new NoArgSQLFunction("utc_timestamp", Hibernate.STRING) );
		registerFunction("week", new StandardSQLFunction("week", Hibernate.INTEGER) );
		registerFunction("weekday", new StandardSQLFunction("weekday", Hibernate.INTEGER) );
		registerFunction("weekofyear", new StandardSQLFunction("weekofyear", Hibernate.INTEGER) );
		registerFunction("year", new StandardSQLFunction("year", Hibernate.INTEGER) );
		registerFunction("yearweek", new StandardSQLFunction("yearweek", Hibernate.INTEGER) );

		registerFunction("hex", new StandardSQLFunction("hex", Hibernate.STRING) );
		registerFunction("oct", new StandardSQLFunction("oct", Hibernate.STRING) );

		registerFunction("octet_length", new StandardSQLFunction("octet_length", Hibernate.LONG) );
		registerFunction("bit_length", new StandardSQLFunction("bit_length", Hibernate.LONG) );

		registerFunction("bit_count", new StandardSQLFunction("bit_count", Hibernate.LONG) );
		registerFunction("encrypt", new StandardSQLFunction("encrypt", Hibernate.STRING) );
		registerFunction("md5", new StandardSQLFunction("md5", Hibernate.STRING) );
		registerFunction("sha1", new StandardSQLFunction("sha1", Hibernate.STRING) );
		registerFunction("sha", new StandardSQLFunction("sha", Hibernate.STRING) );

		registerFunction( "concat", new StandardSQLFunction( "concat", Hibernate.STRING ) );

		getDefaultProperties().setProperty(Environment.MAX_FETCH_DEPTH, "2");
		getDefaultProperties().setProperty(Environment.STATEMENT_BATCH_SIZE, DEFAULT_BATCH_SIZE);
	}

	public String getAddColumnString() {
		return "add column";
	}
	
	public boolean qualifyIndexName() {
		return false;
	}

	public boolean supportsIdentityColumns() {
		return true;
	}
	
	public String getIdentitySelectString() {
		return "select last_insert_id()";
	}

	public String getIdentityColumnString() {
		return "not null auto_increment"; //starts with 1, implicitly
	}

	public String getAddForeignKeyConstraintString(
			String constraintName, 
			String[] foreignKey, 
			String referencedTable, 
			String[] primaryKey, boolean referencesPrimaryKey
	) {
		String cols = StringHelper.join(", ", foreignKey);
		return new StringBuffer(30)
			.append(" add index ")
			.append(constraintName)
			.append(" (")
			.append(cols)
			.append("), add constraint ")
			.append(constraintName)
			.append(" foreign key (")
			.append(cols)
			.append(") references ")
			.append(referencedTable)
			.append(" (")
			.append( StringHelper.join(", ", primaryKey) )
			.append(')')
			.toString();
	}

	public boolean supportsLimit() {
		return true;
	}
	
	public String getDropForeignKeyString() {
		return " drop foreign key ";
	}

	public String getLimitString(String sql, boolean hasOffset) {
		return new StringBuffer( sql.length()+20 )
			.append(sql)
			.append( hasOffset ? " limit ?, ?" : " limit ?")
			.toString();
	}
	
	/*
	 * Temporary, until MySQL fix Connector/J bug
	 */
	/*public String getLimitString(String sql, int offset, int limit) {
		StringBuffer buf = new StringBuffer( sql.length()+20 )
			.append(sql);
		if (offset>0) {
			buf.append(" limit ")
				.append(offset)
				.append(", ")
				.append(limit);
		}
		else {
			buf.append(" limit ")
				.append(limit);
		}
		return buf.toString();
	}*/

	/*
	 * Temporary, until MySQL fix Connector/J bug
	 */
	/*public boolean supportsVariableLimit() {
		return false;
	}*/

	public char closeQuote() {
		return '`';
	}

	public char openQuote() {
		return '`';
	}

	public boolean supportsIfExistsBeforeTableName() {
		return true;
	}

	public char getSchemaSeparator() {
	  return '_';
	}

	public String getSelectGUIDString() {
		return "select uuid()";
	}

	public boolean supportsCascadeDelete() {
		return false;
	}
	
	public String getTableComment(String comment) {
		return " comment='" + comment + "'";
	}

	public String getColumnComment(String comment) {
		return " comment '" + comment + "'";
	}

	public boolean supportsTemporaryTables() {
		return true;
	}

	public String getTemporaryTableCreationCommand() {
		return "create temporary table if not exists";
	}

	public String getCastTypeName(int code) {
		if ( code==Types.INTEGER ) {
			return "signed";
		}
		else {
			return super.getCastTypeName( code );
		}
	}

	public boolean supportsCurrentTimestampSelection() {
		return true;
	}

	public boolean isCurrentTimestampSelectStringCallable() {
		return false;
	}

	public String getCurrentTimestampSelectString() {
		return "select now()";
	}
}
