package org.kuali.db;
   
   import java.io.IOException;
   import java.io.InputStreamReader;
   import java.io.Reader;
   import java.util.Properties;
   
   import org.apache.commons.io.IOUtils;
   import org.springframework.core.io.DefaultResourceLoader;
  import org.springframework.core.io.Resource;
  import org.springframework.util.PropertyPlaceholderHelper;
  
  /**
   * 
   *
   */
  public class SQLGenerator {
  	PropertyPlaceholderHelper helper = new PropertyPlaceholderHelper("${", "}");
  	JDBCUtils jdbcUtils = new JDBCUtils();
  	DefaultResourceLoader loader = new DefaultResourceLoader();
  	String encoding;
  	Properties properties;
  	String url;
  	DatabaseCommand command;
  	String prefix = "classpath:org/kuali/db/";
  
  	public SQLGenerator() {
  		this(null, null, null);
  	}
  
  	public SQLGenerator(Properties properties, String url, DatabaseCommand command) {
  		super();
  		this.properties = properties;
  		this.url = url;
  		this.command = command;
  	}
  
  	protected String getSQLLocation() {
  		return getLocation("/" + getPackageFriendlyName(command.toString()) + ".sql");
  	}
  
  	public String getSQL() throws IOException {
  		String location = getSQLLocation();
  		Resource resource = loader.getResource(location);
  		String sql = IOUtils.toString(resource.getInputStream(), getEncoding());
  		Properties customProperties = getCustomProperties();
  		if (properties != null) {
  			customProperties.putAll(properties);
  		}
  		sql = helper.replacePlaceholders(sql, customProperties);
  		return sql;
  	}
  
  	protected String getPackageFriendlyName(String s) {
  		return s.toLowerCase().replace("_", "");
  	}
  
  	protected String getLocation(String suffix) {
  		JDBCConfiguration jdbcConfiguration = jdbcUtils.getDatabaseConfiguration(url);
  		DatabaseType type = jdbcConfiguration.getType();
  		String packageFriendlyName = getPackageFriendlyName(type.toString());
  		String location = prefix + packageFriendlyName + suffix;
  		return location;
  	}
  
  	protected String getCustomPropertiesLocation() {
  		return getLocation("/custom.properties");
  	}
  
  	protected Properties getCustomProperties() throws IOException {
  		String location = getCustomPropertiesLocation();
  		Reader input = null;
  		try {
  			Resource resource = loader.getResource(location);
  			input = new InputStreamReader(resource.getInputStream(), getEncoding());
  			Properties p = new Properties();
  			p.load(input);
  			return p;
  		} finally {
  			IOUtils.closeQuietly(input);
  		}
  	}
  
  	public String getEncoding() {
  		return encoding;
  	}
  
  	public void setEncoding(String encoding) {
  		this.encoding = encoding;
  	}
  
  	public Properties getProperties() {
  		return properties;
  	}
  
  	public void setProperties(Properties properties) {
  		this.properties = properties;
  	}
  
 	public String getUrl() {
 		return url;
 	}
 
 	public void setUrl(String url) {
 		this.url = url;
 	}
 
 	public DatabaseCommand getCommand() {
 		return command;
 	}
 
 	public void setCommand(DatabaseCommand command) {
 		this.command = command;
 	}
 
 	public PropertyPlaceholderHelper getHelper() {
 		return helper;
 	}
 
 	public void setHelper(PropertyPlaceholderHelper helper) {
 		this.helper = helper;
 	}
 
 	public JDBCUtils getJdbcUtils() {
 		return jdbcUtils;
 	}
 
 	public void setJdbcUtils(JDBCUtils jdbcUtils) {
 		this.jdbcUtils = jdbcUtils;
 	}
 
 	public DefaultResourceLoader getLoader() {
 		return loader;
 	}
 
 	public void setLoader(DefaultResourceLoader loader) {
 		this.loader = loader;
 	}
 
 	public String getPrefix() {
 		return prefix;
 	}
 
 	public void setPrefix(String prefix) {
 		this.prefix = prefix;
 	}
 
 }