/*
    * This file is part of dependency-check-core.
    *
    * 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.
   *
   * Copyright (c) 2020 The OWASP Foundation. All Rights Reserved.
   */
  package org.owasp.dependencycheck.data.nvd.ecosystem;
  
  import java.util.Objects;
  import java.util.Optional;
  import java.util.TreeMap;
  
  import javax.annotation.concurrent.NotThreadSafe;
  
  import io.github.jeremylong.openvulnerability.client.nvd.DefCveItem;
  import io.github.jeremylong.openvulnerability.client.nvd.Reference;
  
  import com.hankcs.algorithm.AhoCorasickDoubleArrayTrie;
  import com.hankcs.algorithm.AhoCorasickDoubleArrayTrie.Hit;
  import io.github.jeremylong.openvulnerability.client.nvd.CveItem;
  import java.util.List;
  
  @NotThreadSafe
  public class UrlEcosystemMapper {
  
      /**
       * The ecosystem map.
       */
      private static final TreeMap<String, String> ECOSYSTEM_MAP;
  
      /**
       * TThe search array.
       */
      private final AhoCorasickDoubleArrayTrie<String> search;
  
      static {
          ECOSYSTEM_MAP = new TreeMap<>();
          for (UrlHostHint urlHostHint : UrlHostHint.values()) {
              ECOSYSTEM_MAP.put(urlHostHint.getValue(), urlHostHint.getEcosystem());
          }
          for (UrlPathHint urlPathHint : UrlPathHint.values()) {
              ECOSYSTEM_MAP.put(urlPathHint.getValue(), urlPathHint.getEcosystem());
          }
      }
  
      /**
       * Constructs a new URL ecosystem mapper.
       */
      public UrlEcosystemMapper() {
          search = new AhoCorasickDoubleArrayTrie<>();
          search.build(ECOSYSTEM_MAP);
      }
  
      /**
       * Determines the ecosystem for the given CVE.
       *
       * @param cve the CVE data
       * @return the ecosystem
       */
      public String getEcosystem(DefCveItem cve) {
          final List<Reference> references = Optional.ofNullable(cve)
                  .map(DefCveItem::getCve)
                  .map(CveItem::getReferences)
                  .orElse(null);
  
          if (Objects.nonNull(references)) {
              for (Reference r : references) {
                  final Hit<String> ecosystem = search.findFirst(r.getUrl());
                  if (ecosystem != null) {
                      return ecosystem.value;
                  }
              }
          }
          return null;
      }
  }