package de.uhilger.um.api;

import de.uhilger.baselink.GenericRecord;
import de.uhilger.baselink.PersistenceManager;
import de.uhilger.baselink.Record;
import de.uhilger.um.App;
import de.uhilger.um.daten.User;
import de.uhilger.um.daten.UserRole;
import java.sql.Connection;
import java.util.List;
import org.apache.catalina.realm.RealmBase;

/**
 * Klasse zur Verwaltung von Benutzern und Rollen 
 * in einer Datenbank
 * 
 * Das SQL findet sich in WEB-INF/sql.properties
 * 
 * @author Ulrich Hilger
 */
public class UserMgr {
  
  private static final String MD5 = "MD5";
  
  private static final Record UserMapper = new GenericRecord(User.class);
  private static final Record UserRoleMapper = new GenericRecord(UserRole.class);
  
  public static final String SQL_GET_USER_LIST = "getUserList";
  public static final String SQL_GET_USER_NAME_LIST = "getUserNameList";
  public static final String SQL_GET_ROLE_LIST = "getRoleList";
  public static final String SQL_GET_USER_ROLES = "getUserRoles";
  public static final String SQL_DELETE_USER = "deleteUser";
  public static final String SQL_DELETE_USER_ROLES = "deleteUserRoles";
  
  /* ----------- Benutzer -------------- */
  
  public User createUser(User user) {
    String kw = user.getPw();
    String digestedPw = RealmBase.Digest(kw, MD5, null);
    user.setPw(digestedPw);
    App.getDatabase().insert(user, UserMapper);
    return user;
  }
  
  public List getUserNameList() {
    String sql = App.getSqlStatement(SQL_GET_USER_NAME_LIST);
    List userNames = App.getDatabase().select(sql, App.WITHOUT_BLOBS);
    return userNames;
  }
  
  public User deleteUser(User user) {
    PersistenceManager pm = App.getDatabase();
    Connection c = pm.getConnection();
    pm.startTransaction(c);
    String sql = App.getSqlStatement(SQL_DELETE_USER_ROLES);
    pm.execute(c, sql, user.getId());
    User deletedUser = (User) pm.delete(c, user, UserMapper);
    pm.commit(c);
    return deletedUser;
  }
    
  /* ------------ Rollen ------------------ */
  
  public UserRole grantRole(String userId, String roleName) {
    UserRole ur = new UserRole();
    ur.setRole(roleName);
    ur.setUser(userId);
    App.getDatabase().insert(ur, UserRoleMapper);
    return ur;
  }
  
  public UserRole revokeRole(String userId, String roleName) {
    UserRole ur = new UserRole();
    ur.setRole(roleName);
    ur.setUser(userId);
    App.getDatabase().delete(ur, UserRoleMapper);
    return ur;
  }
  
  public List getRoleNamesGranted() {
    String sql = App.getSqlStatement(SQL_GET_ROLE_LIST);
    List roleNames = App.getDatabase().select(sql, App.WITHOUT_BLOBS);
    return roleNames;
  }
  
  public List getUserRoleNames(String userId) {
    String sql = App.getSqlStatement(SQL_GET_USER_ROLES);
    List roleNames = App.getDatabase().select(sql, App.WITHOUT_BLOBS, userId);
    return roleNames;
  }
  
}