/*
    * 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   *
    *                                                              *
   *   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.apache.rat.analysis;
  
  import java.util.Collection;
  import java.util.Collections;
  
  import org.apache.rat.analysis.matchers.AbstractMatcherContainer;
  import org.apache.rat.license.ILicense;
  import org.apache.rat.license.ILicenseFamily;
  
  /**
   * A collection of ILicenses that acts as a single License for purposes of Analysis.
   * <p>
   * This class process each license in turn on each {@code matches(String)} call.  When a match is found the 
   * ILicenseFamily for the matching license is captured and used as the family for this license. If no matching 
   * license has been found the default {@code dummy} license category is used.
   */
  class LicenseCollection extends AbstractMatcherContainer implements ILicense {
  
      private static final ILicenseFamily DEFAULT = ILicenseFamily.builder().setLicenseFamilyCategory("Dummy")
              .setLicenseFamilyName("HeaderMatcherCollection default license family").build();
      private final Collection<ILicense> enclosed;
      private ILicense matchingLicense;
      private State lastState;
  
      /**
       * Constructs the LicenseCollection from the provided ILicense collection.
       * @param enclosed The collection of ILicenses to compose this License implementation from.  May not be null.
       */
      public LicenseCollection(Collection<ILicense> enclosed) {
          super(enclosed);
          this.enclosed = Collections.unmodifiableCollection(enclosed);
          this.matchingLicense = null;
          this.lastState = State.i;
      }
  
      @Override
      public String getId() {
          return "Default License Collection";
      }
  
      @Override
      public void reset() {
          enclosed.forEach(ILicense::reset);
          this.lastState = State.i;
          this.matchingLicense = null;
      }
  
      @Override
      public State matches(String line) {
          State dflt = State.f;
          for (ILicense license : enclosed) {
              switch (license.matches(line)) {
              case t:
                  this.matchingLicense = license;
                  lastState = State.t;
                  return State.t;
              case i:
                  dflt = State.i;
                  break;
              default:
                  // do nothing
                  break;
              }
          }
          lastState = dflt;
          return dflt;
      }
  
      @Override
      public State currentState() {
          if (lastState == State.t) {
              return lastState;
          }
          for (ILicense license : enclosed) {
              switch (license.currentState()) {
              case t:
                  this.matchingLicense = license;
                  lastState = State.t;
                  return lastState;
              case i:
                  lastState = State.i;
                 return lastState;
             case f:
                 // do nothing;
                 break;
             }
         }
         lastState = State.f;
         return lastState;
     }
 
     @Override
     public int compareTo(ILicense arg0) {
         return getLicenseFamily().compareTo(arg0.getLicenseFamily());
     }
 
     @Override
     public ILicenseFamily getLicenseFamily() {
         return matchingLicense == null ? DEFAULT : matchingLicense.getLicenseFamily();
     }
 
     @Override
     public String getNotes() {
         return matchingLicense == null ? null : matchingLicense.getNotes();
     }
 
     @Override
     public String derivedFrom() {
         return matchingLicense == null ? null : matchingLicense.derivedFrom();
     }
     
     @Override
     public String getName() {
         return getLicenseFamily().getFamilyName();
     }
 }