/*
    *    Copyright 2015-2022 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
    *
    *       https://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.mybatis.scripting.freemarker;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  
  import freemarker.ext.beans.BeanModel;
  import freemarker.ext.beans.BeansWrapperBuilder;
  import freemarker.template.TemplateHashModel;
  import freemarker.template.TemplateModel;
  import freemarker.template.TemplateModelException;
  import freemarker.template.Version;
  
  /**
   * Important: if you are using some object that already has property "p", then MyBatisParamDirective will be unavailable
   * from script.
   *
   * @author elwood
   */
  public class ParamObjectAdapter implements TemplateHashModel {
    private final BeanModel beanModel;
    private final ArrayList generatedParams;
    private HashMap<String, TemplateModel> additionalParams;
  
    public ParamObjectAdapter(Object paramObject, ArrayList generatedParams, Version incompatibleImprovementsVersion) {
      beanModel = new BeanModel(paramObject, new BeansWrapperBuilder(incompatibleImprovementsVersion).build());
      this.generatedParams = generatedParams;
    }
  
    /**
     * Puts the additional parameter into adapter, it will be available if no existing property with same key exists. For
     * example, it is suitable to add custom objects and directives into dataContext.
     */
    public void putAdditionalParam(String key, TemplateModel value) {
      if (additionalParams == null) {
        additionalParams = new HashMap<>();
      }
      additionalParams.put(key, value);
    }
  
    public ArrayList getGeneratedParams() {
      return generatedParams;
    }
  
    @Override
    public TemplateModel get(String key) throws TemplateModelException {
      // Trying to get bean property
      TemplateModel value = beanModel.get(key);
  
      // If no value retrieved, trying to find the key in additional params
      if (value == null && additionalParams != null && additionalParams.containsKey(key)) {
        return additionalParams.get(key);
      }
  
      // If it is GENERATED_PARAMS_KEY, returning wrapper of generated params list
      if (value == null && FreeMarkerSqlSource.GENERATED_PARAMS_KEY.equals(key)) {
        return new GeneratedParamsTemplateModel(generatedParams);
      }
  
      return value;
    }
  
    @Override
    public boolean isEmpty() throws TemplateModelException {
      return beanModel.isEmpty();
    }
  }