package com.dy.common.webListener;

import com.dy.common.util.IDLongGenerator;
import com.dy.common.util.NumUtil;
import jakarta.servlet.ServletContext;
import jakarta.servlet.ServletContextEvent;
import jakarta.servlet.ServletContextListener;
import lombok.extern.slf4j.Slf4j;

@Slf4j
public class GenerateIdSetSuffixListener implements ServletContextListener {

    //
    public static final String IdSuffix = "idSuffix" ;

    @Override
    public void contextInitialized(ServletContextEvent event) {
        ServletContextListener.super.contextInitialized(event);
        ServletContext con = event.getServletContext();
        this.init(con);
    }

    @Override
    public void contextDestroyed(ServletContextEvent event) {
        ServletContextListener.super.contextDestroyed(event);
    }


    /**
     * 解析系统配置
     */
    private void init(ServletContext con){
        try {
            String idSuffix = con.getInitParameter(IdSuffix);
            if(idSuffix == null || idSuffix.trim().equals("")){
                throw new Exception("未配置ID后缀") ;
            }else{
                if(!NumUtil.isPlusIntNumber(idSuffix)){
                    throw new Exception("配置ID后缀格式不正确") ;
                }else{
                    IDLongGenerator.setSuffix(Integer.parseInt(idSuffix));
                }
            }
        } catch (Exception e) {
            log.error("系统启动时，初始化ID后缀出错 !", e);
        }
    }
}