package com.DX_57.SR_57;
/** include default packages for Beans */
import java.io.Serializable;
import javax.enterprise.context.SessionScoped;
   // or import javax.faces.bean.SessionScoped;
import javax.inject.Named;
/** include package for SHA-256 encryption */
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/** include SQL Packages */
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import javax.annotation.Resource;
import javax.faces.context.FacesContext;
import javax.inject.Inject;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
   // or import javax.faces.bean.ManagedBean;
import org.DX_57.osgi.CL_27.api.CryptoSHA;
import org.glassfish.osgicdi.OSGiService;
import org.DX_57.osgi.SH_27.api.SessionHandle;


@Named("loginController")

@SessionScoped

public class userCheck implements Serializable {
    private String user = null;
    private String password = null;
    private String error_Message = null;
    private String error_Database = null;

       public userCheck(){
       }

       /** Call the Oracle JDBC Connection driver */
       @Resource(name="jdbc/Oracle")
       private DataSource ds;

       /** Call OSGI Bundle SH_27 Session Handle */
       /** Use transient in order to disable serialization when calling OSGI Bundle */
       @Inject @OSGiService(dynamic=true) transient SessionHandle hello;

       public String CallOSGI() throws SQLException{
            return hello.CheckUserDB("Duke");
       }

       /** Call OSGI Bundle CL_27 Crypto Library */
       @Inject @OSGiService(dynamic=true) transient CryptoSHA cryptoString;

       public String zwwe(){
            return cryptoString.sayHello("Duke");
       }


       /** get the content of the variables from the JSF Login page */
       public void setUser(String newValue) {
           user = newValue;
       }

       public String getUser(){
           return user;
       }

       public void setPassword(String newValue) {
           password = newValue;
       }

       public String getPassword(){
           return password;
       }

       public String geterror_Database(){
           return error_Database;
       }

       public String geterror_Message(){
           return error_Message;
       }

       /** method for converting simple string into SHA-256 hash */
       public String string_hash(String hash) throws NoSuchAlgorithmException{

            MessageDigest md = MessageDigest.getInstance("SHA-256");
            md.update(hash.getBytes());

            byte byteData[] = md.digest();

            /** convert the byte to hex format */
            StringBuilder sb = new StringBuilder();
                for (int i = 0; i < byteData.length; i++) {
            sb.append(Integer.toString((byteData[i] & 0xff) + 0x100, 16).substring(1));
            }
           return sb.toString();
       }

       /** method for checking password into the Oracle database */
       public String CheckUserDB(String userToCheck) throws SQLException {
            String storedPassword = null;
            error_Message = null;
            String SQL_Statement = null;

            if (ds == null) throw new SQLException( error_Database = "No data source");
       Connection conn = ds.getConnection();
            if (conn == null) throw new SQLException( error_Database = "No connection");

       try {
            conn.setAutoCommit(false);
            boolean committed = false;
                try {
                       SQL_Statement = "SELECT Passwd from USERS WHERE Username = ?";

                       PreparedStatement passwordQuery = conn.prepareStatement(SQL_Statement);
                       passwordQuery.setString(1, userToCheck);

                       ResultSet result = passwordQuery.executeQuery();

                       if(result.next()){
                            storedPassword = result.getString("Passwd");
                       }

                       conn.commit();
                       committed = true;
                 } finally {
                       if (!committed) conn.rollback();
                       }
            }
                finally {
                conn.close();

                }
       /** if the user is not found or password don't match display error message*/
       if (storedPassword == null){
           error_Message = "Invalid Username!";
       } else {
           error_Message = "Invalid Password!";
       }

       return storedPassword;
       }

       /** method for inserting user credentials into user sessions table */

       /*
        *CREATE TABLE "ACTIVESESSIONS"(
  "SessionId" Char(20 ) NOT NULL,
  "UserId" Varchar2(30 ) NOT NULL,
  "LoginTime" Timestamp(6),
  "LastRefreshTime" Timestamp(6),
  "UserIP" Varchar2(30 ),
  "UserBrowserID" Varchar2(30 )
)
/
        */

       public void SessionRegister (String UpdateUser) throws SQLException{
           String  SQL_Statement = null;
           error_Message = null;

       /** get user session id */
       FacesContext fCtx = FacesContext.getCurrentInstance();
       HttpSession session = (HttpSession) fCtx.getExternalContext().getSession(false);
       String sessionId = session.getId();

       /** get user IP address */
       FacesContext context = FacesContext.getCurrentInstance();
       HttpServletRequest request = (HttpServletRequest)context.getExternalContext().getRequest();
       String remoteHost = request.getRemoteAddr();


            if (ds == null) throw new SQLException( error_Database = "No data source");
       Connection conn = ds.getConnection();
            if (conn == null) throw new SQLException( error_Database = "No connection");

       try {
            conn.setAutoCommit(false);
            boolean committed = false;
                try {           /* insert into Oracle the default system(Linux) time */
                       SQL_Statement = "INSERT INTO ACTIVESESSIONS (SessionId, UserId, LoginTime, LastRefreshTime,"
                               + "UserIP, UserBrowserID)VALUES ('" + sessionId + "', '" + UpdateUser
                               + "' , current_timestamp, current_timestamp, '" + remoteHost + "', 'jjjk')";

                       PreparedStatement insertQuery = conn.prepareStatement(SQL_Statement);
                       insertQuery.executeUpdate();

                       conn.commit();
                       committed = true;
                 } finally {
                       if (!committed) conn.rollback();
                       }
            }
                finally {
                conn.close();

                }

           return;
       }

       /** compare the user and the password */
       public String userCompare() throws NoSuchAlgorithmException, SQLException {
            String hash_passwd = null;
            String passwdQuery = null;



            /** check the password into Oracle using the username */
            passwdQuery = CheckUserDB(user);

            /** convert the plain password in SHA-256 hash */
            hash_passwd = string_hash(password);

            /** compare the encrypted passwords */
            if (password.equals(passwdQuery)){      // naro4no nekriptirani se sravnqvat
                /** insert into users session table the time when the user login */
                SessionRegister(user);
                /* success */

                String stri = CallOSGI();

                return "0";
            } else {
                /* failer */
                return "1";
            }
       }

}