/*
    * Copyright 2016 the original author or authors.
    *
    * Licensed 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
    *
    *       http://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 org.openehealth.ipf.boot.fhir;
  
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
  import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
  import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
  import org.springframework.boot.context.properties.ConfigurationProperties;
  import org.springframework.boot.context.properties.EnableConfigurationProperties;
  import org.springframework.boot.web.servlet.FilterRegistrationBean;
  import org.springframework.context.annotation.Bean;
  import org.springframework.context.annotation.Configuration;
  import org.springframework.web.cors.CorsConfiguration;
  import org.springframework.web.filter.CorsFilter;
  
  import java.util.Arrays;
  
  
  @Configuration
  @EnableConfigurationProperties(IpfFhirConfigurationProperties.class)
  @ConditionalOnWebApplication
  @ConditionalOnProperty(prefix = "ipf.fhir.cors", name = "enabled", havingValue = "true", matchIfMissing = true)
  public class CorsAutoConfiguration {
  
      @Autowired
      private IpfFhirConfigurationProperties config;
  
      @Bean
      @ConditionalOnMissingBean(CorsConfiguration.class)
      @ConfigurationProperties(prefix = "ipf.fhir.cors")
      public CorsConfiguration corsConfiguration() {
          CorsConfiguration config = new CorsConfiguration();
  
          // A comma separated list of allowed origins. Note: An '*' cannot be used for an allowed origin when using credentials.
          config.addAllowedOrigin("*");
          config.setAllowedMethods(Arrays.asList("GET","POST","PUT","DELETE","OPTIONS"));
          // A comma separated list of allowed headers when making a non simple CORS request.
          config.setAllowedHeaders(Arrays.asList("X-FHIR-Starter", "Origin", "Accept", "X-Requested-With", "Content-Type", "Access-Control-Request-Method", "Access-Control-Request-Headers", "Authorization"));
          config.setExposedHeaders(Arrays.asList("Location", "Content-Location"));
          config.setMaxAge(300L);
          return config;
      }
  
      @Bean
      @ConditionalOnMissingBean(name = "corsFilterRegistration")
      public FilterRegistrationBean corsFilterRegistration(CorsConfiguration corsConfiguration) {
          FilterRegistrationBean frb = new FilterRegistrationBean();
          frb.addUrlPatterns(config.getFhirMapping());
          frb.setFilter(new CorsFilter(request -> corsConfiguration));
          return frb;
      }
  
  }