package at.gv.egovernment.moa.id.config;

import java.math.BigInteger;
import java.security.Principal;
import java.security.cert.X509Certificate;
import java.util.Map;

import at.gv.egovernment.moa.id.data.IssuerAndSerial;

/**
 * Base class for <code>AuthConfigurationProvider</code> and <code>ProxyConfigurationProvider</code>,
 * providing functions common to both of them.
 *
 * @author Paul Ivancsics
 * @version $Id$
 */
public class ConfigurationProvider {

  /**
   * Constructor
   */
  public ConfigurationProvider() {
    super();
  }

  /** 
   * The name of the system property which contains the file name of the 
   * configuration file.
   */
  public static final String CONFIG_PROPERTY_NAME =
    "moa.id.configuration";

  /**
   * The name of the generic configuration property giving the certstore directory path.
   */
  public static final String DIRECTORY_CERTSTORE_PARAMETER_PROPERTY =
    "DirectoryCertStoreParameters.RootDir";

  /**
     * A <code>Map</code> which contains generic configuration information. Maps a
     * configuration name (a <code>String</code>) to a configuration value (also a
     * <code>String</code>).
     */
  protected Map genericConfiguration;

  /** The default chaining mode. */
  protected String defaultChainingMode;

  /** 
     * A <code>Map</code> which contains the <code>IssuerAndSerial</code> to
     * chaining mode (a <code>String</code>) mapping.
     */
  protected Map chainingModes;

  /**
     * the URL for the trusted CA Certificates
     */
  protected String trustedCACertificates;

  /**
     * Returns the mapping of generic configuration properties.
     * 
     * @return The mapping of generic configuration properties (a name to value
     * mapping) from the configuration.
     */
  public Map getGenericConfiguration() {
    return genericConfiguration;
  }

  /**
     * Returns the value of a parameter from the generic configuration section.
     * 
     * @return the parameter value; <code>null</code> if no such parameter
     */
  public String getGenericConfigurationParameter(String parameter) {
  	if (! genericConfiguration.containsKey(parameter))
  		return null;
    return (String)genericConfiguration.get(parameter);
  }

  /**
     * Return the chaining mode for a given trust anchor.
     * 
     * @param trustAnchor The trust anchor for which the chaining mode should be
     * returned.
     * @return The chaining mode for the given trust anchor. If the trust anchor
     * has not been configured separately, the system default will be returned.
     */
  public String getChainingMode(X509Certificate trustAnchor) {
    Principal issuer = trustAnchor.getIssuerDN();
    BigInteger serial = trustAnchor.getSerialNumber();
    IssuerAndSerial issuerAndSerial = new IssuerAndSerial(issuer, serial);
  
    String mode = (String) chainingModes.get(issuerAndSerial);
    return mode != null ? mode : defaultChainingMode;
  }

  /**
   * Returns the trustedCACertificates.
   * @return String
   */
  public String getTrustedCACertificates() {
    return trustedCACertificates;
  }
}