/**
    * Copyright 2005-2013 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.rice.krms.framework.engine;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  
  import org.kuali.rice.krms.api.engine.ExecutionEnvironment;
  import org.kuali.rice.krms.api.engine.TermResolver;
  
  /**
   * An implementation of {@link Context}
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public final class BasicContext implements Context {
  	
  	private final List<Agenda> agendas;
  	private final List<TermResolver<?>> termResolvers;
  
      /**
       * Create a BasicContext with the given parameters
       * @param agendas List<{@link}Agenda}> to set the agendas to
       * @param termResolvers List<{@link TermResolver}<?>> to set the termResolvers to
       */
  	public BasicContext(List<Agenda> agendas, List<TermResolver<?>> termResolvers) {
  		this.agendas = agendas;
  		this.termResolvers = termResolvers;
  	}
  	
  	@Override
  	public void execute(ExecutionEnvironment environment) {
  		if (termResolvers != null) for (TermResolver<?> termResolver : termResolvers) {
  			environment.addTermResolver(termResolver);
  		}
  		List<Agenda> matchingAgendas = findMatchingAgendas(environment);
  		for (Agenda matchingAgenda : matchingAgendas) {
  			matchingAgenda.execute(environment);
  		}
  	}
  
      /**
       * Return {@link Agenda}s that appliesTo the given {@link ExecutionEnvironment}
       * @param environment {@link ExecutionEnvironment} to apply to
       * @return List<{@link Agenda}> that match
       */
  	private List<Agenda> findMatchingAgendas(ExecutionEnvironment environment) {
  		List<Agenda> matchingAgendas = new ArrayList<Agenda>();
  		for (Agenda agenda : agendas) {
  			if (agenda.appliesTo(environment)) {
  				matchingAgendas.add(agenda);
  			}
  		}
  		return matchingAgendas;
  	}
  
      @Override
  	public List<TermResolver<?>> getTermResolvers() {
  		return Collections.unmodifiableList(termResolvers);
  	}
  
  }