package org.argeo.cms.auth;
   
   import java.util.List;
   
   import javax.naming.InvalidNameException;
   import javax.naming.ldap.LdapName;
   import javax.naming.ldap.Rdn;
   
   import org.argeo.api.NodeConstants;
  import org.argeo.cms.CmsException;
  import org.argeo.naming.LdapAttrs;
  import org.osgi.service.useradmin.Role;
  import org.osgi.service.useradmin.User;
  import org.osgi.service.useradmin.UserAdmin;
  
  /** Centralise common patterns to manage users with a {@link UserAdmin} */
  public class UserAdminUtils {
  
  	// CURRENTUSER HELPERS
  	/** Checks if current user is the same as the passed one */
  	public static boolean isCurrentUser(User user) {
  		String userUsername = getProperty(user, LdapAttrs.DN);
  		LdapName userLdapName = getLdapName(userUsername);
  		LdapName selfUserName = getCurrentUserLdapName();
  		return userLdapName.equals(selfUserName);
  	}
  
  	/** Retrieves the current logged-in {@link User} */
  	public static User getCurrentUser(UserAdmin userAdmin) {
  		return (User) userAdmin.getRole(CurrentUser.getUsername());
  	}
  
  	/** Retrieves the current logged-in user {@link LdapName} */
  	public final static LdapName getCurrentUserLdapName() {
  		String name = CurrentUser.getUsername();
  		return getLdapName(name);
  	}
  
  	/** Retrieves the current logged-in user mail */
  	public static String getCurrentUserMail(UserAdmin userAdmin) {
  		String username = CurrentUser.getUsername();
  		return getUserMail(userAdmin, username);
  	}
  
  	/** Retrieves the current logged-in user common name */
  	public final static String getCommonName(User user) {
  		return getProperty(user, LdapAttrs.cn.name());
  	}
  
  	// OTHER USERS HELPERS
  	/**
  	 * Retrieves the local id of a user or group, that is respectively the uid or cn
  	 * of the passed dn with no {@link UserAdmin}
  	 */
  	public static String getUserLocalId(String dn) {
  		LdapName ldapName = getLdapName(dn);
  		Rdn last = ldapName.getRdn(ldapName.size() - 1);
  		if (last.getType().toLowerCase().equals(LdapAttrs.uid.name())
  				|| last.getType().toLowerCase().equals(LdapAttrs.cn.name()))
  			return (String) last.getValue();
  		else
  			throw new CmsException("Cannot retrieve user local id, non valid dn: " + dn);
  	}
  
  	/**
  	 * Returns the local username if no user with this dn is found or if the found
  	 * user has no defined display name
  	 */
  	public static String getUserDisplayName(UserAdmin userAdmin, String dn) {
  		Role user = userAdmin.getRole(dn);
  		String dName;
  		if (user == null)
  			dName = getUserLocalId(dn);
  		else {
  			dName = getProperty(user, LdapAttrs.displayName.name());
  			if (isEmpty(dName))
  				dName = getProperty(user, LdapAttrs.cn.name());
  			if (isEmpty(dName))
  				dName = getUserLocalId(dn);
  		}
  		return dName;
  	}
  
  	/**
  	 * Returns null if no user with this dn is found or if the found user has no
  	 * defined mail
  	 */
  	public static String getUserMail(UserAdmin userAdmin, String dn) {
  		Role user = userAdmin.getRole(dn);
  		if (user == null)
  			return null;
  		else
  			return getProperty(user, LdapAttrs.mail.name());
  	}
  
  	// LDAP NAMES HELPERS
  	/**
  	 * Easily retrieves one of the {@link Role}'s property or an empty String if the
  	 * requested property is not defined
 	 */
 	public final static String getProperty(Role role, String key) {
 		Object obj = role.getProperties().get(key);
 		if (obj != null)
 			return (String) obj;
 		else
 			return "";
 	}
 
 	public final static String getProperty(Role role, Enum<?> key) {
 		Object obj = role.getProperties().get(key.name());
 		if (obj != null)
 			return (String) obj;
 		else
 			return "";
 	}
 
 	public final static void setProperty(Role role, String key, String value) {
 		role.getProperties().put(key, value);
 	}
 
 	public final static void setProperty(Role role, Enum<?> key, String value) {
 		setProperty(role, key.name(), value);
 	}
 
 	/**
 	 * Simply retrieves a LDAP name from a {@link LdapAttrs.DN} with no exception
 	 */
 	private static LdapName getLdapName(String dn) {
 		try {
 			return new LdapName(dn);
 		} catch (InvalidNameException e) {
 			throw new CmsException("Cannot parse LDAP name " + dn, e);
 		}
 	}
 
 	/** Simply retrieves a display name of the relevant domain */
 	public final static String getDomainName(User user) {
 		String dn = user.getName();
 		if (dn.endsWith(NodeConstants.ROLES_BASEDN))
 			return "System roles";
 		if (dn.endsWith(NodeConstants.TOKENS_BASEDN))
 			return "Tokens";
 		try {
 			// FIXME deal with non-DC
 			LdapName name = new LdapName(dn);
 			List<Rdn> rdns = name.getRdns();
 			String dname = null;
 			int i = 0;
 			loop: while (i < rdns.size()) {
 				Rdn currrRdn = rdns.get(i);
 				if (!LdapAttrs.dc.name().equals(currrRdn.getType()))
 					break loop;
 				else {
 					String currVal = (String) currrRdn.getValue();
 					dname = dname == null ? currVal : currVal + "." + dname;
 				}
 				i++;
 			}
 			return dname;
 		} catch (InvalidNameException e) {
 			throw new CmsException("Unable to get domain name for " + dn, e);
 		}
 	}
 
 	// VARIOUS HELPERS
 	public final static String buildDefaultCn(String firstName, String lastName) {
 		return (firstName.trim() + " " + lastName.trim() + " ").trim();
 	}
 
 	/** Simply checks if a string is null or empty */
 	private static boolean isEmpty(String stringToTest) {
 		return stringToTest == null || "".equals(stringToTest.trim());
 	}
 
 }