/*
 * Copyright 2009 by primedata Corporation. Address:TianChuang Technology Building, CaiHeFang
 * Road,Haidian District, Beijing
 *
 * All rights reserved.
 *
 * This software is the confidential and proprietary information of primedata
 * Corporation ("Confidential Information"). You shall not disclose such
 * Confidential Information and shall use it only in accordance with the terms
 * of the license agreement you entered into with primedata.
 */
package com.primeton.dgs.kernel.core.web;

import java.io.IOException;
import java.util.HashSet;
import java.util.Set;

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

import net.sf.json.JSONArray;


import com.eos.data.datacontext.UserObject;
import com.primeton.dgs.kernel.core.common.ActionHelper;
import com.primeton.dgs.kernel.core.common.ActionResult;
import com.primeton.dgs.kernel.core.util.ExUtils;
import com.primeton.licensemanager.checklicense.VerifyHLicenseException;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.AntPathMatcher;
import org.springframework.util.PathMatcher;

/**
 * mvc主控 Servlet
 *
 * @author user
 * @version 1.0 2006-9-18
 */
public class MainServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    private Logger log = LoggerFactory.getLogger(MainServlet.class);

    public static final String ENCODE = "UTF-8";

    String loginPath = "/login.do";

    /**
     * 无需认证即可访问的白名单
     */
    protected Set<String> authWriteList = new HashSet<>();


    /**
     * Initialize global variables
     */
    public void init() throws ServletException {
        log.info("MainServlet init.");
    }

    /**
     * Process the HTTP Get request
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        perform(request, response);
    }

    /**
     * Process the HTTP Post request
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        perform(request, response);
    }

    /**
     * Process the HTTP request
     */
    public void perform(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setCharacterEncoding(ENCODE);
        String next = "";
        try {
            String path = request.getServletPath();
            String name = request.getParameter("invoke");

            // 获取登录信息
            Object userObject = request.getSession().getAttribute("userObject");
            // 登录动作，不要拦截
            //解决当session失效时，请求报错，后台报空指针,页面跳转到非登录页面
            Object userProfile = request.getSession().getAttribute("com.primeton.dgs.workspace.system.common.UserProfile");

            // 检查是否已经登录
            if ((null == userObject && null == userProfile) || name == null) {
                // 未登录，是否在白名单
                String resourcePath = request.getRequestURI().replaceAll(request.getContextPath(), "");
                boolean cross = false;
                PathMatcher matcher = new AntPathMatcher();
                for (String s : authWriteList) {
                    cross = matcher.match(s, resourcePath);
                    if(cross) {
                        // 一旦通过一个，则进行下一步校验
                        break;
                    }
                }

                // name is null 或者 不通过
                if(name == null || !cross) {
                    dispatch(request, response, WebViewer.LONGIN_PAGE);
                    return;
                }
            }

            request.setAttribute("invoke", name);
            AbstractCommand cmd = CommandFactory.getInstance().getCommand(path);

            cmd.init(request, response, getServletConfig());

            next = cmd.execute();
            if (null != next) {
                dispatch(request, response, next);
            }
        } catch (VerifyHLicenseException e) {
            if (isExt(request)) {
                performOnError(request, response, e);
                return;
            }
            request.setAttribute("javax.servlet.jspException", e);
            dispatch(request, response, WebViewer.LICENSE_PAGE);
        } catch (Exception e) {
            log.error("MainServlet catch an error:", e);
            if (isExt(request)) {
                performOnError(request, response, e);
                return;
            }
            request.setAttribute("_CommandExecuteException_",
                    ExUtils.getMessage(request, e));
            request.setAttribute("javax.servlet.jspException", e);
            dispatch(request, response, WebViewer.VIEW_ERROR);
        }

    }

    public void performOnError(HttpServletRequest request,
                               HttpServletResponse response, Exception e) throws ServletException,
            IOException {
        String msg = ExUtils.getMessage(request, e);
        ActionResult rs = new ActionResult(false, msg);
        rs.put("list", new JSONArray());
        try {
            if (isReturnXml(request)) {
                ActionHelper.outputXmlList(response, null, 0, rs);
            } else {
                ActionHelper.output(response, rs);
            }
        } catch (Exception er) {
            throw new ServletException(er);
        }
    }

    public void dispatch(HttpServletRequest request,
                          HttpServletResponse response, String page) throws ServletException,
            IOException {
        log.info("Command dispath request to: " + page);
        if (page.toLowerCase().startsWith("http:")
                || page.toLowerCase().startsWith("https:")) {
            response.sendRedirect(page);
        } else {
            request.getRequestDispatcher(page).forward(request, response);
        }
    }


    /**
     * 添加排除
     * @param s
     * @return
     */
    public boolean addExclude(String s) {
        if(StringUtils.isBlank(s)) {
            return false;
        }
        return authWriteList.add(StringUtils.trim(s));
    }

    public static boolean isExt(HttpServletRequest request) {
        return "Ext".equalsIgnoreCase(request.getHeader("Request-By"));
    }

    public static boolean isReturnXml(HttpServletRequest request) {
        return "XML".equalsIgnoreCase(request.getHeader("Response-By"));
    }

}