/*
 * 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.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.Cookie;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.apache.commons.lang3.StringUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.lang.NonNull;
import org.springframework.lang.Nullable;
import org.springframework.security.authentication.RememberMeAuthenticationToken;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.authentication.RememberMeServices;
import org.springframework.security.web.authentication.rememberme.AbstractRememberMeServices;
import org.springframework.util.Assert;
import org.springframework.web.util.WebUtils;

import java.io.IOException;

/**
 * Created by aalexeev on 4/5/17.
 */
public class HashParamAuthenticationFilter extends BaseAuthenticationFilter {

    public static final String PARAM_NAME = "hash";

    private final UserService userService;
    private final RememberMeServices rememberMeServices;

    public HashParamAuthenticationFilter(
            @NonNull final UserService userService,
            @Nullable final RememberMeServices rememberMeServices) {
        Assert.notNull(userService, "userService should not be null");

        this.userService = userService;
        this.rememberMeServices = rememberMeServices;
    }

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

        String hash = getHashFromRequest(request);
        if (hash != null && authenticationIsRequired()) {
            User user = userService.getUserByHash(hash);
            if (!user.isAnonymous()) {
                User userWithPassword = userService.getUserByName(user.getName());
                userWithPassword.setAuthHash(userService.getHashByUID(userWithPassword.getUid()));
                if (rememberMeServices != null) {
                    // web login should create cookie
                    var authentication = new RememberMeAuthenticationToken(
                            ((AbstractRememberMeServices) rememberMeServices).getKey(),
                            new JuickUser(userWithPassword), JuickUser.USER_AUTHORITY);
                    SecurityContextHolder.getContext().setAuthentication(authentication);
                    rememberMeServices.loginSuccess(request, response, authentication);
                } else {
                    Authentication authentication = new UsernamePasswordAuthenticationToken(
                            new JuickUser(userWithPassword),
                            userWithPassword.getCredentials(),
                            JuickUser.USER_AUTHORITY);
                    SecurityContextHolder.getContext().setAuthentication(authentication);
                }
            }
        }

        filterChain.doFilter(request, response);
    }

    private String hashFromAuthorizationHeader(HttpServletRequest request) {
        String authorizationHeader = request.getHeader(HttpHeaders.AUTHORIZATION);
        if (StringUtils.isNotEmpty(authorizationHeader)) {
            String[] parts = authorizationHeader.split(" ");
            if ((parts.length == 2) && parts[0].equals("Juick")) {
                return parts[1];
            }
        }
        return StringUtils.EMPTY;
    }

    private String getHashFromRequest(HttpServletRequest request) {
        String paramHash = request.getParameter(PARAM_NAME);
        Cookie cookieHash = WebUtils.getCookie(request, PARAM_NAME);
        String headerHash = hashFromAuthorizationHeader(request);

        if (StringUtils.isNotEmpty(headerHash)) {
            return headerHash;
        }
        if (paramHash == null && cookieHash != null) {
            return cookieHash.getValue();
        }
        return paramHash;
    }
}