/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */
package grails.plugin.springsecurity.rest.token.bearer

import groovy.transform.CompileStatic
import groovy.util.logging.Slf4j

import jakarta.servlet.ServletException
import jakarta.servlet.http.HttpServletRequest
import jakarta.servlet.http.HttpServletResponse

import org.springframework.security.core.AuthenticationException
import org.springframework.security.web.AuthenticationEntryPoint

import grails.plugin.springsecurity.rest.token.AccessToken

/**
 * Handles prompting the client for authentication when using bearer tokens.
 */
@Slf4j
@CompileStatic
class BearerTokenAuthenticationEntryPoint implements AuthenticationEntryPoint {

    BearerTokenReader tokenReader

    @Override
    void commence(HttpServletRequest request, HttpServletResponse response, AuthenticationException authException)
            throws IOException, ServletException {
        AccessToken accessToken = tokenReader.findToken(request)

        if (accessToken) {
            response.addHeader('WWW-Authenticate', 'Bearer error="invalid_token"')
        } else {
            response.addHeader('WWW-Authenticate', 'Bearer')
        }
        response.sendError(HttpServletResponse.SC_UNAUTHORIZED)

    }
}
