package com.qrsx.exam.struts.action;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

import com.qrsx.exam.Constants;
import com.qrsx.exam.dao.DAOFactory;
import com.qrsx.exam.dao.StudentDAO;
import com.qrsx.exam.dao.TeacherDAO;
import com.qrsx.exam.dao.UserDAO;
import com.qrsx.exam.model.Student;
import com.qrsx.exam.model.Teacher;
import com.qrsx.exam.model.User;
import com.qrsx.exam.struts.BaseAction;
import com.qrsx.exam.struts.form.UserForm;

/**
 * The action about user login
 * 
 * @struts.action name="userForm" path="/logon" scope="request"
 *                input="/logon.jsp" validate="false" parameter="p"
 *                roles="unspecified,logon"
 * 
 * @struts.action-forward name="admin" path="/admin.jsp"
 * 
 * @struts.action-forward name="student" path="/student.jsp"
 * 
 * @struts.action-forward name="teacher" path="/teacher.jsp"
 * 
 * @struts.action-forward name="password" path="/manage/password.jsp"
 * 
 * @author Administrator
 * 
 */
public class LogonAction extends BaseAction {
    protected final Log log = LogFactory.getLog(getClass());

    /**
     * 缺省的處理方法 其功能是跳轉到登錄頁面
     */
    @Override
    public ActionForward unspecified(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        return mapping.getInputForward();
    }

    /**
     * 用戶登錄功能
     */
    public ActionForward logon(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        // 得到用戶提交的參數
        UserForm user = (UserForm) form;

        // 檢索用戶信息
        UserDAO dao = DAOFactory.getDao(UserDAO.class);
        User u = dao.getUserByName(user.getName());
        if (u != null && u.getPassword().equals(user.getPassword())) {
            // 登錄成功，保存用戶信息到Session中
            HttpSession session = request.getSession();
            session.setAttribute(Constants.SESSION_USER, u);
            return mapping.findForward(u.getUserType());
        }

        // 登錄失敗，設置提示信息，返回登錄頁面
        addMessage(request, "logon.failed");

        return mapping.getInputForward();
    }

    /**
     * 用戶退出登錄功能
     */
    public ActionForward logoff(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        HttpSession session = request.getSession();
        session.invalidate();

        return mapping.getInputForward();
    }

    /**
     * 進入用戶修改密碼頁面
     */
    public ActionForward passwordin(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        return mapping.findForward("password");
    }

    /**
     * 用戶修改密碼功能
     */
    public ActionForward password(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        // 得到用戶提交的信息
        UserForm user = (UserForm) form;

        // 得到當前用戶的信息
        HttpSession session = request.getSession();
        User u = (User) session.getAttribute(Constants.SESSION_USER);

        // 取得用戶輸入的舊密碼
        String oldpassword = request.getParameter("oldpassword");
        if (u.getPassword().equals(oldpassword)) {
            // 修改用戶密碼
            if (u.isAdmin()) {
                UserDAO dao = DAOFactory.getDao(UserDAO.class);
                User us = dao.findById(u.getId(), true);
                us.setPassword(user.getPassword());
                session.setAttribute(Constants.SESSION_USER, us);
            } else if (u.isTeacher()) {
                TeacherDAO dao = DAOFactory.getDao(TeacherDAO.class);
                Teacher t = dao.findById(u.getId(), true);
                t.setPassword(user.getPassword());
                session.setAttribute(Constants.SESSION_USER, t);
            } else {
                StudentDAO dao = DAOFactory.getDao(StudentDAO.class);
                Student s = dao.findById(u.getId(), true);
                s.setPassword(user.getPassword());
                session.setAttribute(Constants.SESSION_USER, s);
            }

            // 設置修改成功的提示信息
            addMessage(request, "user.msg.pwdsuccess");
        } else {
            // 設置修改失敗的提示信息
            addMessage(request, "user.msg.pwdfail");
        }
        return mapping.findForward("password");
    }

    /**
     * 跳轉到用戶首頁的方法
     */
    public ActionForward homepage(ActionMapping mapping, ActionForm form,
            HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        // 得到當前登錄用戶的信息
        HttpSession session = request.getSession();
        User u = (User) session.getAttribute(Constants.SESSION_USER);

        // 跳轉到用戶的首頁
        return mapping.findForward(u.getUserType());
    }
}