package cn.van.business.filter;

import cn.van.business.service.impl.UserDetailsServiceImpl;
import cn.van.business.util.JwtUtils;
import jakarta.servlet.FilterChain;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.NonNull;
import lombok.RequiredArgsConstructor;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import java.io.IOException;

@Component
@RequiredArgsConstructor
public class JwtAuthFilter extends OncePerRequestFilter {

    private final JwtUtils jwtUtils;
    private final UserDetailsServiceImpl userDetailsService;

    @Override
    protected void doFilterInternal(@NonNull HttpServletRequest request,
                                    @NonNull HttpServletResponse response,
                                    @NonNull FilterChain filterChain)
            throws ServletException, IOException {
        try {
            logger.debug("JwtAuthFilter.doFilterInternal");
            String jwt = parseJwt(request);
            if (jwt != null && jwtUtils.validateToken(jwt)) {
                String username = jwtUtils.extractUsername(jwt);

                UserDetails userDetails = userDetailsService.loadUserByUsername(username);
                UsernamePasswordAuthenticationToken authentication = new UsernamePasswordAuthenticationToken(
                        userDetails, null, userDetails.getAuthorities());

                authentication.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
                SecurityContextHolder.getContext().setAuthentication(authentication);
            }

        } catch (Exception e) {
            logger.error("无法认证用户: {}");
        }

        filterChain.doFilter(request, response);
    }

    private String parseJwt(HttpServletRequest request) {
        String headerAuth = request.getHeader("Authorization");

        if (StringUtils.hasText(headerAuth) && headerAuth.startsWith("Bearer ")) {
            return headerAuth.substring(7);
        }

        return null;
    }
}
