/*
    * Portions of this software was developed by employees of the National Institute
    * of Standards and Technology (NIST), an agency of the Federal Government and is
    * being made available as a public service. Pursuant to title 17 United States
    * Code Section 105, works of NIST employees are not subject to copyright
    * protection in the United States. This software may be subject to foreign
    * copyright. Permission in the United States and in foreign countries, to the
    * extent that NIST may hold copyright, to use, copy, modify, create derivative
    * works, and distribute this software and its documentation without fee is hereby
   * granted on a non-exclusive basis, provided that this notice and disclaimer
   * of warranty appears in all copies.
   *
   * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
   * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
   * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
   * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
   * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE.  IN NO EVENT
   * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
   * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
   * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
   * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
   * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
   * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
   */
  
  package gov.nist.secauto.metaschema.schemagen.json.schema;
  
  import com.fasterxml.jackson.databind.node.ArrayNode;
  import com.fasterxml.jackson.databind.node.JsonNodeFactory;
  import com.fasterxml.jackson.databind.node.ObjectNode;
  
  import gov.nist.secauto.metaschema.core.model.IAssemblyDefinition;
  import gov.nist.secauto.metaschema.core.model.IChoiceInstance;
  import gov.nist.secauto.metaschema.core.model.IFlagInstance;
  import gov.nist.secauto.metaschema.core.model.IModelInstance;
  import gov.nist.secauto.metaschema.core.model.INamedModelInstance;
  import gov.nist.secauto.metaschema.core.model.ModelType;
  import gov.nist.secauto.metaschema.core.util.CollectionUtil;
  import gov.nist.secauto.metaschema.core.util.ObjectUtils;
  import gov.nist.secauto.metaschema.schemagen.FlagInstanceFilter;
  import gov.nist.secauto.metaschema.schemagen.json.impl.JsonGenerationState;
  import gov.nist.secauto.metaschema.schemagen.json.property.FlagInstanceJsonProperty;
  import gov.nist.secauto.metaschema.schemagen.json.property.IJsonProperty.PropertyCollection;
  import gov.nist.secauto.metaschema.schemagen.json.property.INamedModelInstanceJsonProperty;
  
  import java.io.IOException;
  import java.util.Collection;
  import java.util.LinkedList;
  import java.util.List;
  
  import edu.umd.cs.findbugs.annotations.NonNull;
  
  public class AssemblyDefinitionJsonSchema
      extends AbstractDefinitionJsonSchema<IAssemblyDefinition> {
  
    public AssemblyDefinitionJsonSchema(
        @NonNull IAssemblyDefinition definition) {
      super(definition);
    }
  
    @Override
    public void resolveSubSchemas(JsonGenerationState state) {
      for (IFlagInstance instance : getDefinition().getFlagInstances()) {
        state.getSchema(instance.getDefinition());
      }
  
      for (INamedModelInstance instance : getDefinition().getNamedModelInstances()) {
        state.getSchema(instance.getDefinition());
      }
    }
  
    @Override
    protected void generateBody(JsonGenerationState state, ObjectNode obj) throws IOException {
      IAssemblyDefinition definition = getDefinition();
  
      obj.put("type", "object");
  
      // determine the flag instances to generate
      IFlagInstance jsonKeyFlag = definition.getJsonKeyFlagInstance();
      Collection<? extends IFlagInstance> flags
          = FlagInstanceFilter.filterFlags(definition.getFlagInstances(), jsonKeyFlag);
  
      PropertyCollection properties = new PropertyCollection();
  
      // generate flag properties
      for (IFlagInstance flag : flags) {
        assert flag != null;
        new FlagInstanceJsonProperty(flag).generateProperty(properties, state); // NOPMD instantiation needed
      }
      // generate model properties
      Collection<? extends INamedModelInstance> instances = definition.getNamedModelInstances();
      for (INamedModelInstance instance : instances) {
        assert instance != null;
        INamedModelInstanceJsonProperty.newProperty(instance)
            .generateProperty(properties, state);
      }
  
      Collection<? extends IChoiceInstance> choices = definition.getChoiceInstances();
     if (choices.isEmpty()) {
       properties.generate(obj);
 
       obj.put("additionalProperties", false);
     } else {
       generateChoices(choices, properties, obj, state);
     }
   }
 
   protected void generateChoices(
       @NonNull Collection<? extends IChoiceInstance> choices,
       @NonNull PropertyCollection properties,
       @NonNull ObjectNode definitionNode,
       @NonNull JsonGenerationState state) throws IOException {
     List<PropertyCollection> propertyChoices = CollectionUtil.singletonList(properties);
     propertyChoices = explodeChoices(choices, propertyChoices, state);
 
     if (propertyChoices.size() == 1) {
       propertyChoices.iterator().next().generate(definitionNode);
     } else if (propertyChoices.size() > 1) {
       ArrayNode anyOfdNode = ObjectUtils.notNull(JsonNodeFactory.instance.arrayNode());
       for (PropertyCollection propertyChoice : propertyChoices) {
         ObjectNode choiceDefinitionNode = ObjectUtils.notNull(JsonNodeFactory.instance.objectNode());
         propertyChoice.generate(choiceDefinitionNode);
         choiceDefinitionNode.put("additionalProperties", false);
         anyOfdNode.add(choiceDefinitionNode);
       }
       definitionNode.set("anyOf", anyOfdNode);
     }
   }
 
   protected List<PropertyCollection> explodeChoices(
       @NonNull Collection<? extends IChoiceInstance> choices,
       @NonNull List<PropertyCollection> propertyChoices,
       @NonNull JsonGenerationState state) throws IOException {
 
     List<PropertyCollection> retval = propertyChoices;
 
     for (IChoiceInstance choice : choices) {
       List<PropertyCollection> newRetval = new LinkedList<>(); // NOPMD - intentional
       for (IModelInstance optionInstance : choice.getModelInstances()) {
         if (ModelType.CHOICE.equals(optionInstance.getModelType())) {
           // recurse
           newRetval.addAll(explodeChoices(
               CollectionUtil.singleton((IChoiceInstance) optionInstance),
               retval,
               state));
         } else {
           // iterate over the old array of choices and append new choice
           for (PropertyCollection oldInstanceProperties : retval) {
             @SuppressWarnings("null")
             @NonNull PropertyCollection newInstanceProperties = oldInstanceProperties.copy();
 
             // add the choice
             INamedModelInstanceJsonProperty.newProperty((INamedModelInstance) optionInstance)
                 .generateProperty(newInstanceProperties, state);
 
             newRetval.add(newInstanceProperties);
           }
         }
       }
       retval = newRetval;
     }
     return retval;
   }
 }