package com.smtaiserver.smtaiserver.web;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import com.smtservlet.core.SMTRequest;
import com.smtservlet.util.SMTJsonWriter;
import com.smtservlet.util.SMTStatic;



public class SMTAIServerWebFilter implements Filter {

	static Logger _logger = LogManager.getLogger(SMTAIServerWebFilter.class);
	@Override
	public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException 
	{
		try
		{
			String Origin = ((HttpServletRequest)servletRequest).getHeader("Origin");
			HttpServletResponse resp = (HttpServletResponse)servletResponse;
			resp.addHeader("Access-Control-Allow-Origin", SMTStatic.isNullOrEmpty(Origin) ? "*" : Origin);
			resp.addHeader("Access-Control-Allow-Credentials", "true");
			resp.addHeader("Access-Control-Allow-Headers", System.getProperty("smt_http_allow_headers", "hswatersession,referrer-policy,content-type,authorization"));
			resp.setContentType("application/json;charset=utf-8");
			//resp.setHeader("Pragma","No-cache");
			//resp.setHeader("Cache-Control","no-cache");
			//resp.setDateHeader("Expires", 0);
			HttpServletRequest request = (HttpServletRequest)servletRequest;
			
			String swaggerUIFlag = System.getProperty("swagger_ui", "true");
			if(swaggerUIFlag == null)
				swaggerUIFlag = "";
			if(!"true".equals(swaggerUIFlag))
			{
				String servPath = request.getRequestURI();

				if(servPath.equals("/swagger-ui.html") || servPath.startsWith("/webjars/") || 
				  servPath.startsWith("/swagger-raw.html") || servPath.equals("/swagger-resources/configuration/security"))
				{
					resp.setStatus(404);
					resp.setContentType("text/plain;charset=utf-8");
					ServletOutputStream os = resp.getOutputStream();
					os.println("404 : swagger_ui=[" + swaggerUIFlag + "]");
					os.flush();
					return;
				}
			}
			filterChain.doFilter(servletRequest,servletResponse);

		}
		catch(Exception ex)
		{
			Throwable realEX = ex.getCause();
			if(realEX == null)
				realEX = ex;
			
			_logger.fatal("doFilter exception", realEX);
			
			ServletOutputStream os = servletResponse.getOutputStream();
			try
			{
				SMTJsonWriter jsonWr = new SMTJsonWriter(false);
				jsonWr.addKeyValue("json_ok", false);
				jsonWr.addKeyValue("json_msg", realEX.getMessage());
				jsonWr.addKeyValue("json_error", realEX.getMessage());
				os.write(jsonWr.getFullJson().getBytes("UTF-8"));
			}
			finally
			{
				os.close();
			}
		}
		finally
		{
			SMTRequest.destroyInstance((HttpServletRequest)servletRequest);
		}
	}

}