package com.vci.starter.web.interceptor;

import com.vci.starter.web.constant.TokenKeyConstant;
import com.vci.starter.web.enumpck.LangCodeEnum;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.lang.Nullable;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.support.RequestContextUtils;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Locale;

/**
 * 本地化控制拦截器
 * @author weidy
 * @date 2019/11/7 12:22 PM
 */
public class VciLocaleInterceptor implements HandlerInterceptor {

    /**
     * 日志对象
     */
    protected final Logger logger = LoggerFactory.getLogger(getClass());

    /**
     * 执行拦截
     * @param request 请求对象
     * @param response 相应对象
     * @param handler 处理器
     * @return 是否成功,false表示失败，其他的拦截器将不会执行
     * @throws Exception 执行出错时会抛出异常
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
            throws Exception {
        //从参数或者头里获取
        String newLocale = request.getParameter(TokenKeyConstant.LANGUAGE_KEY);
        if(StringUtils.isBlank(newLocale)){
            newLocale = request.getHeader(TokenKeyConstant.LANGUAGE_KEY);
            if(logger.isDebugEnabled() && StringUtils.isNotBlank(newLocale)) {
                logger.debug("本地化参数在数据头中存放，当前是被调用的服务。{}", newLocale);
            }
//            if(StringUtils.isBlank(newLocale)){
//                newLocale = LangCodeEnum.ZH_CN.getValue();
//            }
        }
        //如果没有传递就不设置，因为多语言有默认值
        if (StringUtils.isNotBlank(newLocale)) {
            LocaleResolver localeResolver = RequestContextUtils.getLocaleResolver(request);
            if (localeResolver == null) {
                throw new IllegalStateException(
                        "No LocaleResolver found: not in a DispatcherServlet request?");
            }
            try {
                localeResolver.setLocale(request, response, parseLocaleValue(newLocale));
                if(logger.isDebugEnabled()) {
                    logger.debug("本地化为{}", newLocale);
                }
            }catch (IllegalArgumentException ex) {
                if(logger.isDebugEnabled()) {
                    logger.debug("Ignoring invalid locale value [{}]:{} " ,newLocale,ex.getMessage());
                }
            }
        }
        return true;
    }

    /**
     * 根据语言的编码获取本地化对象
     * @param localeValue 本地化编码
     * @return 本地化对象
     */
    @Nullable
    protected Locale parseLocaleValue(String localeValue) {
        return org.springframework.util.StringUtils.parseLocale(localeValue);
    }

}