/*
    * Copyright (c) 2005, Henri Yandell
    * All rights reserved.
    * 
    * Redistribution and use in source and binary forms, with or 
    * without modification, are permitted provided that the 
    * following conditions are met:
    * 
    * + Redistributions of source code must retain the above copyright notice, 
   *   this list of conditions and the following disclaimer.
   * 
   * + Redistributions in binary form must reproduce the above copyright notice, 
   *   this list of conditions and the following disclaimer in the documentation 
   *   and/or other materials provided with the distribution.
   * 
   * + Neither the name of Simple-JNDI nor the names of its contributors 
   *   may be used to endorse or promote products derived from this software 
   *   without specific prior written permission.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  package org.osjava.sj.loader;
  
  import java.sql.Connection;
  import java.sql.SQLException;
  import javax.sql.DataSource;
  import java.sql.DriverManager;
  import java.io.PrintWriter;
  import java.util.Properties;
  
  /***
   * A basic implementation of a DataSource. 
   */
  public class SJDataSource implements DataSource {
  
      private PrintWriter pw;
      private String username;
      private String password;
      private String url;
      private String driver;
  
      // for pooling
      private Properties properties;
  
      /***
       * if a connection pool has been built, its url is stored in here
       */
      private String poolUrl = null;
  
      public SJDataSource(String driver, String url, String username, String password, Properties properties) {
          ensureLoaded(driver);
          this.driver = driver;
          this.url = url;
          this.pw = new PrintWriter(System.err);
          this.username = username;
          this.password = password;
          this.properties = properties;
      }
  
      // Method from Apache Commons DbUtils
      private static boolean ensureLoaded(String name) {
          try {
              Class.forName(name).newInstance();
              return true;
          } catch (Exception e) {
              return false;
          }
      }
  
      public Connection getConnection() throws SQLException {
          return this.getConnection(this.username, this.password);
      }
  
      /***
       * returns a connection to the database specified in the properties and
       * creates a connection pool, if neccessary 
       */
      public Connection getConnection(String username, String password) throws SQLException {
          String tmpUrl = this.url;
  
          String pool = properties.getProperty("pool");
          if (pool != null) {  // we want a connection name named like the pool property
              synchronized (SJDataSource.class) {
                  if (poolUrl == null) {  // we didn't create a connection pool already, so do it now
                      PoolSetup.setupConnection(pool, url, username, password, properties);
                      poolUrl = PoolSetup.getUrl(pool);
                  }
              }
             tmpUrl = poolUrl;  // url is now a pooling link
         }
 
         if(username == null || password == null) {
             return DriverManager.getConnection(tmpUrl);
         }
         return DriverManager.getConnection(tmpUrl, username, password);
     }
 
     public PrintWriter getLogWriter() throws SQLException {
         return pw;
     }
 
     public int getLoginTimeout() throws SQLException {
         return 0;
     }
 
     public void setLogWriter(PrintWriter pw) throws SQLException {
         this.pw = pw;
     }
 
     public void setLoginTimeout(int timeout) throws SQLException {
         // ignored
     }
 
     public String toString() {
         return driver + "::::" + url + "::::" + username;
     }
 
     public boolean equals(Object obj) {
         if(obj == null) { 
             return false;
         }
         if(obj.getClass() != this.getClass()) {
             return false;
         }
         SJDataSource other = (SJDataSource) obj;
 
         return other.url.equals(this.url) &&
                other.driver.equals(this.driver) &&
                other.username.equals(this.username);
     }
 
     public int hashCode() {
         return this.url.hashCode() & this.username.hashCode() & this.driver.hashCode();
     }
 
     // Added by JDK 1.6 via java.sql.Wrapper
     public boolean isWrapperFor(Class<?> iface) throws SQLException {
          return false;
     }
 
     // Added by JDK 1.6 via java.sql.Wrapper
     public <T>  T unwrap(Class<T> iface) throws SQLException {
         throw new SQLException("This object is not a wrapper");
     }
 
 }