package com.quantum.adapters;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import com.quantum.Messages;

/**
 * @author root
 * Basically this Factory is a Singleton that is used to return the proper adapter
 */
public class AdapterFactory {
	public static final String GENERIC = "GENERIC"; //$NON-NLS-1$
    public static final String ORACLE = "ORACLE"; //$NON-NLS-1$
    public static final String POSTGRES = "POSTGRES"; //$NON-NLS-1$
    public static final String MYSQL = "MYSQL"; //$NON-NLS-1$
    public static final String DB2 = "DB2"; //$NON-NLS-1$
    public static final String DB2AS400 = "DB2AS400"; //$NON-NLS-1$
	public static final String ADABASD = "ADABASD"; //$NON-NLS-1$
    public static final String INFORMIX = "INFORMIX"; //$NON-NLS-1$
	public static final String REDBRICK = "REDBRICK"; //$NON-NLS-1$
    public static final String SYBASE = "SYBASE"; //$NON-NLS-1$

    private static AdapterFactory instance;
    
    private ArrayList drivers;
    
    private AdapterFactory() {
    	loadDrivers();
    }
    public static synchronized AdapterFactory getInstance() {
    	if (instance == null) {
    		instance = new AdapterFactory();
    	}
    	return instance;
    }

    /**
     * Master list of supported drivers
     */
    private void loadDrivers() {
    	drivers = new ArrayList();

		DriverInfo generic = new DriverInfo(GENERIC, Messages.getString("adapters.generic"), new GenericAdapter()); //$NON-NLS-1$
		DriverInfo oracle = new DriverInfo(ORACLE, Messages.getString("adapters.oracle"), new OracleAdapter()); //$NON-NLS-1$
		DriverInfo db2 = new DriverInfo(DB2,  Messages.getString("adapters.db2"), new DB2Adapter()); //$NON-NLS-1$
		DriverInfo db2as400 = new DriverInfo(DB2AS400,  Messages.getString("adapters.db2as400"), new DB2AS400Adapter()); //$NON-NLS-1$
		DriverInfo postgres = new DriverInfo(POSTGRES,  Messages.getString("adapters.postgres"), new PostgresAdapter()); //$NON-NLS-1$
		DriverInfo mysql = new DriverInfo(MYSQL,  Messages.getString("adapters.mysql"), new GenericAdapter()); //$NON-NLS-1$
		DriverInfo adabasd = new DriverInfo(ADABASD, Messages.getString("adapters.adabasd"), new AdabasDAdapter()); //$NON-NLS-1$
        DriverInfo informix = new DriverInfo(INFORMIX, Messages.getString("adapters.informix"), new GenericAdapter()); //$NON-NLS-1$
		DriverInfo redbrick = new DriverInfo(REDBRICK, Messages.getString("adapters.redbrick"), new RedBrickAdapter()); //$NON-NLS-1$
        DriverInfo sybase = new DriverInfo(SYBASE, Messages.getString("adapters.sybase"), new GenericAdapter()); //$NON-NLS-1$

    	drivers.add(generic);
    	drivers.add(oracle);
    	drivers.add(db2);
    	drivers.add(db2as400);
    	drivers.add(postgres);
    	drivers.add(mysql);
		drivers.add(adabasd);
        drivers.add(informix);
		drivers.add(redbrick);
        drivers.add(sybase);
    }
    
    public synchronized DatabaseAdapter getAdapter(String type){
    	if (drivers == null) {
    		loadDrivers();
    	}
    	for (int i = 0; i < drivers.size(); i++) {
    		DriverInfo info = (DriverInfo) drivers.get(i);
    		if (type.equals(info.getDriverType())) {
    			return info.getAdapter();
    		}
    	}
    	// If its not a recognized driver, we return the generic one
		for (int i = 0; i < drivers.size(); i++) {
			DriverInfo info = (DriverInfo) drivers.get(i);
			if (type.equals(GENERIC)) {
				return info.getAdapter();
			}
		}
		return null;
    }
    
    public synchronized DriverInfo[] getDriverList() {
        List list = new ArrayList(this.drivers);
        Collections.sort(list);
    	return (DriverInfo[]) list.toArray(new DriverInfo[list.size()]);
    }
}