/*
    * Copyright 2020-2022 Foreseeti AB <https://foreseeti.com>
    *
    * 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.mal_lang.langspec;
  
  import static java.util.Objects.requireNonNull;
  
  import jakarta.json.Json;
  import jakarta.json.JsonObject;
  import java.util.ArrayList;
  import java.util.LinkedHashSet;
  import java.util.List;
  import java.util.Set;
  import org.mal_lang.langspec.builders.AttackStepBuilder;
  import org.mal_lang.langspec.step.StepExpression;
  import org.mal_lang.langspec.ttc.TtcExpression;
  
  /**
   * Immutable class representing an attack step of an asset in a MAL language.
   *
   * @since 1.0.0
   */
  public final class AttackStep {
    private final String name;
    private final Meta meta;
    private final Asset asset;
    private final AttackStepType type;
    private final Set<String> tags;
    private final Risk risk;
    private final TtcExpression ttc;
    private final Steps requires;
    private final Steps reaches;
  
    private AttackStep(
        String name,
        Meta meta,
        Asset asset,
        AttackStepType type,
        List<String> tags,
        Risk risk,
        TtcExpression ttc,
        Steps requires,
        Steps reaches) {
      this.name = requireNonNull(name);
      this.meta = requireNonNull(meta);
      this.asset = requireNonNull(asset);
      this.type = requireNonNull(type);
      this.tags = new LinkedHashSet<>(requireNonNull(tags));
      this.risk = risk;
      this.ttc = ttc;
      this.requires = requires;
      this.reaches = reaches;
    }
  
    /**
     * Returns the name of this {@code AttackStep} object.
     *
     * @return the name of this {@code AttackStep} object
     * @since 1.0.0
     */
    public String getName() {
      return this.name;
    }
  
    /**
     * Returns the meta info of this {@code AttackStep} object.
     *
     * @return the meta info of this {@code AttackStep} object
     * @since 1.0.0
     */
    public Meta getMeta() {
      return this.meta;
    }
  
    /**
     * Returns the asset of this {@code AttackStep} object.
     *
     * @return the asset of this {@code AttackStep} object
     * @since 1.0.0
     */
    public Asset getAsset() {
      return this.asset;
    }
  
    /**
     * Returns the type of this {@code AttackStep} object.
    *
    * @return the type of this {@code AttackStep} object
    * @since 1.0.0
    */
   public AttackStepType getType() {
     return this.type;
   }
 
   /**
    * Returns whether {@code name} is the name of a local tag in this {@code AttackStep} object.
    *
    * @param name the name of the local tag
    * @return whether {@code name} is the name of a local tag in this {@code AttackStep} object
    * @throws java.lang.NullPointerException if {@code name} is {@code null}
    * @since 1.0.0
    */
   public boolean hasLocalTag(String name) {
     return this.tags.contains(requireNonNull(name));
   }
 
   /**
    * Returns a list of all local tags in this {@code AttackStep} object.
    *
    * @return a list of all local tags in this {@code AttackStep} object
    * @since 1.0.0
    */
   public List<String> getLocalTags() {
     return List.copyOf(this.tags);
   }
 
   /**
    * Returns whether {@code name} is the name of a tag in this {@code AttackStep} object.
    *
    * @param name the name of the tag
    * @return whether {@code name} is the name of a tag in this {@code AttackStep} object
    * @throws java.lang.NullPointerException if {@code name} is {@code null}
    * @since 1.0.0
    */
   public boolean hasTag(String name) {
     return this.hasLocalTag(name)
         || this.hasSuperAttackStep() && this.getSuperAttackStep().hasTag(name);
   }
 
   /**
    * Returns a list of all tags in this {@code AttackStep} object.
    *
    * @return a list of all tags in this {@code AttackStep} object
    * @since 1.0.0
    */
   public List<String> getTags() {
     return List.copyOf(this.getTagsSet());
   }
 
   private Set<String> getTagsSet() {
     var tagsSet =
         this.hasSuperAttackStep()
             ? this.getSuperAttackStep().getTagsSet()
             : new LinkedHashSet<String>();
     tagsSet.addAll(this.tags);
     return tagsSet;
   }
 
   /**
    * Returns whether this {@code AttackStep} object has a local risk.
    *
    * @return whether this {@code AttackStep} object has a local risk
    * @since 1.0.0
    */
   public boolean hasLocalRisk() {
     return this.risk != null;
   }
 
   /**
    * Returns the local risk of this {@code AttackStep} object.
    *
    * @return the local risk of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     a local risk
    * @since 1.0.0
    */
   public Risk getLocalRisk() {
     if (!this.hasLocalRisk()) {
       throw new UnsupportedOperationException("Local risk not found");
     }
     return this.risk;
   }
 
   /**
    * Returns whether this {@code AttackStep} object has a risk.
    *
    * @return whether this {@code AttackStep} object has a risk
    * @since 1.0.0
    */
   public boolean hasRisk() {
     return this.hasLocalRisk() || this.hasSuperAttackStep() && this.getSuperAttackStep().hasRisk();
   }
 
   /**
    * Returns the risk of this {@code AttackStep} object.
    *
    * @return the risk of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     a risk
    * @since 1.0.0
    */
   public Risk getRisk() {
     if (!this.hasRisk()) {
       throw new UnsupportedOperationException("Risk not found");
     }
     return this.hasLocalRisk() ? this.getLocalRisk() : this.getSuperAttackStep().getRisk();
   }
 
   /**
    * Returns whether this {@code AttackStep} object has a local TTC.
    *
    * @return whether this {@code AttackStep} object has a local TTC
    * @since 1.0.0
    */
   public boolean hasLocalTtc() {
     return this.ttc != null;
   }
 
   /**
    * Returns the local TTC of this {@code AttackStep} object.
    *
    * @return the local TTC of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     a local TTC
    * @since 1.0.0
    */
   public TtcExpression getLocalTtc() {
     if (!this.hasLocalTtc()) {
       throw new UnsupportedOperationException("Local TTC not found");
     }
     return this.ttc;
   }
 
   /**
    * Returns whether this {@code AttackStep} object has a TTC.
    *
    * @return whether this {@code AttackStep} object has a TTC
    * @since 1.0.0
    */
   public boolean hasTtc() {
     return this.hasLocalTtc() || this.hasSuperAttackStep() && this.getSuperAttackStep().hasTtc();
   }
 
   /**
    * Returns the TTC of this {@code AttackStep} object.
    *
    * @return the TTC of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     a TTC
    * @since 1.0.0
    */
   public TtcExpression getTtc() {
     if (!this.hasTtc()) {
       throw new UnsupportedOperationException("TTC not found");
     }
     return this.hasLocalTtc() ? this.getLocalTtc() : this.getSuperAttackStep().getTtc();
   }
 
   /**
    * Returns whether this {@code AttackStep} object has local requires steps.
    *
    * @return whether this {@code AttackStep} object has local requires steps
    * @since 1.0.0
    */
   public boolean hasLocalRequires() {
     return this.requires != null;
   }
 
   /**
    * Returns the local requires steps of this {@code AttackStep} object.
    *
    * @return the local requires steps of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     local requires steps
    * @since 1.0.0
    */
   public Steps getLocalRequires() {
     if (!this.hasLocalRequires()) {
       throw new UnsupportedOperationException("Local requires not found");
     }
     return this.requires;
   }
 
   /**
    * Returns the requires steps of this {@code AttackStep} object.
    *
    * @return the requires steps of this {@code AttackStep} object
    * @since 1.0.0
    */
   public List<StepExpression> getRequires() {
     return List.copyOf(this.getRequiresList());
   }
 
   private List<StepExpression> getRequiresList() {
     var overrides = this.hasLocalRequires() && this.requires.overrides();
     var requiresList =
         this.hasSuperAttackStep() && !overrides
             ? this.getSuperAttackStep().getRequiresList()
             : new ArrayList<StepExpression>();
     if (this.hasLocalRequires()) {
       requiresList.addAll(this.requires.getStepExpressions());
     }
     return requiresList;
   }
 
   /**
    * Returns whether this {@code AttackStep} object has local reaches steps.
    *
    * @return whether this {@code AttackStep} object has local reaches steps
    * @since 1.0.0
    */
   public boolean hasLocalReaches() {
     return this.reaches != null;
   }
 
   /**
    * Returns the local reaches steps of this {@code AttackStep} object.
    *
    * @return the local reaches steps of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     local reaches steps
    * @since 1.0.0
    */
   public Steps getLocalReaches() {
     if (!this.hasLocalReaches()) {
       throw new UnsupportedOperationException("Local reaches not found");
     }
     return this.reaches;
   }
 
   /**
    * Returns the reaches steps of this {@code AttackStep} object.
    *
    * @return the reaches steps of this {@code AttackStep} object
    * @since 1.0.0
    */
   public List<StepExpression> getReaches() {
     return List.copyOf(this.getReachesList());
   }
 
   private List<StepExpression> getReachesList() {
     var overrides = this.hasLocalReaches() && this.reaches.overrides();
     var reachesList =
         this.hasSuperAttackStep() && !overrides
             ? this.getSuperAttackStep().getReachesList()
             : new ArrayList<StepExpression>();
     if (this.hasLocalReaches()) {
       reachesList.addAll(this.reaches.getStepExpressions());
     }
     return reachesList;
   }
 
   /**
    * Returns whether this {@code AttackStep} object has a super attack step.
    *
    * @return whether this {@code AttackStep} object has a super attack step
    * @since 1.0.0
    */
   public boolean hasSuperAttackStep() {
     return this.asset.hasSuperAsset() && this.asset.getSuperAsset().hasAttackStep(this.name);
   }
 
   /**
    * Returns the super attack step of this {@code AttackStep} object.
    *
    * @return the super attack step of this {@code AttackStep} object
    * @throws java.lang.UnsupportedOperationException if this {@code AttackStep} object does not have
    *     a super attack step
    * @since 1.0.0
    */
   public AttackStep getSuperAttackStep() {
     if (!this.hasSuperAttackStep()) {
       throw new UnsupportedOperationException("Super attack step not found");
     }
     return this.asset.getSuperAsset().getAttackStep(this.name);
   }
 
   JsonObject toJson() {
     var jsonTags = Json.createArrayBuilder();
     for (var tag : this.tags) {
       jsonTags.add(tag);
     }
 
     var jsonAttackStep =
         Json.createObjectBuilder()
             .add("name", this.name)
             .add("meta", this.meta.toJson())
             .add("type", this.type.toString())
             .add("tags", jsonTags);
     if (this.risk == null) {
       jsonAttackStep.addNull("risk");
     } else {
       jsonAttackStep.add("risk", this.risk.toJson());
     }
     if (this.ttc == null) {
       jsonAttackStep.addNull("ttc");
     } else {
       jsonAttackStep.add("ttc", this.ttc.toJson());
     }
     if (this.requires == null) {
       jsonAttackStep.addNull("requires");
     } else {
       jsonAttackStep.add("requires", this.requires.toJson());
     }
     if (this.reaches == null) {
       jsonAttackStep.addNull("reaches");
     } else {
       jsonAttackStep.add("reaches", this.reaches.toJson());
     }
     return jsonAttackStep.build();
   }
 
   static AttackStep fromBuilder(AttackStepBuilder builder, Asset asset) {
     requireNonNull(builder);
     requireNonNull(asset);
     var requires = builder.getRequires() == null ? null : Steps.fromBuilder(builder.getRequires());
     var reaches = builder.getReaches() == null ? null : Steps.fromBuilder(builder.getReaches());
     return new AttackStep(
         builder.getName(),
         Meta.fromBuilder(builder.getMeta()),
         asset,
         builder.getType(),
         builder.getTags(),
         builder.getRisk(),
         builder.getTtc(),
         requires,
         reaches);
   }
 }