package com.kevin.blog.base;

import org.springframework.http.MediaType;

import org.springframework.web.method.HandlerMethod;

import org.springframework.web.servlet.HandlerInterceptor;

import org.springframework.web.servlet.ModelAndView;

import com.kevin.blog.utils.GeneralUtils;

import com.kevin.blog.utils.JsonUtils;

import java.io.IOException;

import java.lang.reflect.Method;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

/**

* Created by KevinBlandy on 2017/5/11 17:58

*/

public abstract class BaseInterceptor <T>implements HandlerInterceptor{

@Override

public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object handler) throws Exception{

if(GeneralUtils.isOptionsRequest(httpServletRequest)) {

return Boolean.TRUE;

}

Method method = null;

if(handler instanceof HandlerMethod) {

method = ((HandlerMethod) handler).getMethod();

}

return this.doPreHandle(httpServletRequest, httpServletResponse,method);

}

@Override

public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {

}

@Override

public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {

}

/**

* 拦截执行

* @param httpServletRequest

* @param httpServletResponse

* @param method

* @return

*/

public abstract boolean doPreHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse,Method method)throws Exception;

/**

* 校验失败,执行响应

* @param httpServletRequest

* @param httpServletResponse

* @param message ajax,请求响应消息

* @param path 同步请求,跳转页面

* @throws IOException

*/

protected void response(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse,T message,String path) throws IOException{

if(GeneralUtils.isAjaxRequest(httpServletRequest)){

this.ajaxResponse(httpServletResponse, message);

}else{

this.htmlRedirect(httpServletRequest, httpServletResponse, path);

}

}

/**

* ajax响应

* @param httpServletResponse

* @param message

* @throws IOException

*/

protected void ajaxResponse(HttpServletResponse httpServletResponse,T message) throws IOException{

httpServletResponse.setContentType(MediaType.APPLICATION_JSON_UTF8_VALUE);

httpServletResponse.getWriter().write(JsonUtils.beanToJson(message));

httpServletResponse.flushBuffer();

}

/**

* Html重定向

* @param httpServletRequest

* @param httpServletResponse

* @param path

* @throws IOException

*/

protected void htmlRedirect(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse,String path) throws IOException{

httpServletResponse.setContentType(MediaType.TEXT_HTML_VALUE + ";charset=utf-8");

String script = "<script>top.location.href=\""+httpServletRequest.getContextPath() + path +"\"</script>";

httpServletResponse.getWriter().write(script);

httpServletResponse.flushBuffer();

}

}