/*
 * Copyright (C) 2008-2020, Juick
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.juick.service.security;

import com.juick.ActivityPubManager;
import com.juick.model.User;
import com.juick.service.UserService;
import com.juick.service.security.entities.JuickUser;
import jakarta.servlet.FilterChain;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.springframework.security.authentication.AnonymousAuthenticationToken;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;

import java.io.IOException;
import java.util.Collections;
import java.util.Map;
import java.util.stream.Collectors;

public class HTTPSignatureAuthenticationFilter extends BaseAuthenticationFilter {

    private final ActivityPubManager activityPubManager;
    private final UserService userService;

    public HTTPSignatureAuthenticationFilter(
            final ActivityPubManager activityPubManager,
            final UserService userService) {
        this.activityPubManager = activityPubManager;
        this.userService = userService;
    }

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response,
            FilterChain filterChain) throws IOException, ServletException {
        if (authenticationIsRequired()) {
            Map<String, String> headers = Collections.list(request.getHeaderNames())
                    .stream()
                    .collect(Collectors.toMap(String::toLowerCase, request::getHeader));
            var user = activityPubManager.verifyActor(request.getMethod(), request.getRequestURI(), headers);
            String userUri = user.getUri().toString();
            if (!user.isAnonymous() || userUri.length() > 0) {
                if (userUri.length() == 0) {
                    User userWithPassword = userService.getUserByName(user.getName());
                    userWithPassword.setAuthHash(userService.getHashByUID(userWithPassword.getUid()));
                    Authentication authentication = new UsernamePasswordAuthenticationToken(
                            new JuickUser(user), userWithPassword.getCredentials(), JuickUser.USER_AUTHORITY);
                    SecurityContextHolder.getContext().setAuthentication(authentication);
                } else {
                    // anonymous must have with uri
                    Authentication authentication = new AnonymousAuthenticationToken(userUri,
                            new JuickUser(user), JuickUser.ANONYMOUS_AUTHORITY);
                    SecurityContextHolder.getContext().setAuthentication(authentication);
                }
            }
        }

        filterChain.doFilter(request, response);
    }
}