package com.vincent.rsf.openApi.security.filter;

import com.vincent.rsf.openApi.entity.constant.Constants;
import com.vincent.rsf.openApi.security.service.AppAuthService;
import com.vincent.rsf.openApi.security.utils.TokenUtils;
import lombok.extern.slf4j.Slf4j;
import org.apache.tika.utils.StringUtils;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.annotation.Resource;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

/**
 * AppId和AppSecret认证过滤器
 * 
 * 用于验证请求头中的AppId和AppSecret
 * 
 * @author vincent
 * @since 2026-01-05
 */
@Slf4j
@Component
@Order(1)
public class AppIdAuthenticationFilter extends OncePerRequestFilter {

    @Resource
    private AppAuthService appAuthService;


    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) 
            throws ServletException, IOException {

        String requestURI = request.getRequestURI();
        
        // 检查是否为认证请求（如获取token）
        if (isAuthRequest(requestURI)) {
            // 对于认证请求，允许通过
            filterChain.doFilter(request, response);
            return;
        }

        String authHeader = request.getHeader(Constants.HEADER_AUTHORIZATION);
        if (authHeader != null) {
            String token = TokenUtils.extractTokenFromHeader(authHeader);
            if (token != null && TokenUtils.validateTokenTime(token)) {
                // Token时间认证成功，认证AppId和AppSecret
                String tokenAppId = TokenUtils.getAppIdFromToken(token);
                String tokenAppSecret = TokenUtils.getSecretFromToken(token);
                if (StringUtils.isBlank(tokenAppId) || StringUtils.isBlank(tokenAppSecret)
                        || !appAuthService.validateApp(tokenAppId, tokenAppSecret)) {
                    log.warn("Token验证失败");
                    sendErrorResponse(response, Integer.parseInt(Constants.UNAUTHENTICATED_CODE), "认证失败，请提供有效的Token");
                    return;
                } else {
                    request.setAttribute(Constants.REQUEST_ATTR_APP_ID, tokenAppId);
                }
            } else {
                log.warn("Token验证失败或缺失");
                sendErrorResponse(response, Integer.parseInt(Constants.UNAUTHENTICATED_CODE), "认证失败，请提供有效的Token");
                return;
            }
        } else {
            log.warn("缺少Token认证信息");
            sendErrorResponse(response, Integer.parseInt(Constants.UNAUTHENTICATED_CODE), "认证失败，请提供有效的Token");
            return;
        }

        filterChain.doFilter(request, response);
    }

    /**
     * 发送错误响应
     * 
     * @param response HTTP响应
     * @param code 错误码
     * @param message 错误消息
     * @throws IOException
     */
    private void sendErrorResponse(HttpServletResponse response, int code, String message) throws IOException {
        response.setStatus(code);
        response.setContentType("application/json;charset=UTF-8");
        PrintWriter writer = response.getWriter();
        writer.write("{\"code\": \"" + code + "\", \"msg\": \"" + message + "\", \"data\": null}");
        writer.flush();
    }

    /**
     * 检查是否为认证请求（不需要认证的请求）
     * 
     * @param requestURI 请求URI
     * @return 是否为认证请求
     */
    private boolean isAuthRequest(String requestURI) {
        return requestURI.contains("/getToken");
//               || requestURI.contains("/auth/validate") ||
//               requestURI.contains("/auth/login");
    }

    @Override
    protected boolean shouldNotFilter(HttpServletRequest request) throws ServletException {
        String requestURI = request.getRequestURI();
        
        // 不过滤认证相关请求和公开接口
        return requestURI.contains("/auth/") || 
               requestURI.contains("/public/") ||
               requestURI.contains("/doc.html") ||
               requestURI.contains("/swagger") ||
               requestURI.contains("/webjars") ||
               requestURI.contains("/v2/api-docs") ||
               requestURI.contains("/v3/api-docs");
    }

}