/*
 * Copyright (C) 2014, United States Government, as represented by the
 * Administrator of the National Aeronautics and Space Administration.
 * All rights reserved.
 *
 * The Java Pathfinder core (jpf-core) platform is 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 gov.nasa.jpf.test.mc.basic;

import gov.nasa.jpf.ListenerAdapter;
import gov.nasa.jpf.util.test.TestJPF;
import gov.nasa.jpf.vm.ChoiceGenerator;
import gov.nasa.jpf.vm.DoubleChoiceGenerator;
import gov.nasa.jpf.vm.Instruction;
import gov.nasa.jpf.vm.IntChoiceGenerator;
import gov.nasa.jpf.vm.ThreadInfo;
import gov.nasa.jpf.vm.VM;
import gov.nasa.jpf.vm.SystemState;
import gov.nasa.jpf.vm.Verify;
import gov.nasa.jpf.vm.choice.DoubleChoiceFromList;
import gov.nasa.jpf.vm.choice.IntIntervalGenerator;

import java.util.Comparator;

import org.junit.Test;

/**
 * regression test for choice reordering APIs 
 */
public class CGReorderTest extends TestJPF {

  public static class ReverseListener extends ListenerAdapter {  
    @Override
    public void choiceGeneratorSet (VM vm, ChoiceGenerator<?> newCG){
      if (newCG instanceof IntIntervalGenerator){
        System.out.println("reverse choice enumeration order");
        ((IntIntervalGenerator)newCG).reverse();
      }
    }

    int lastVal = Integer.MAX_VALUE;
    @Override
    public void choiceGeneratorAdvanced (VM vm, ChoiceGenerator<?> currentCG){
      if (currentCG instanceof IntIntervalGenerator){
        int v = ((IntChoiceGenerator)currentCG).getNextChoice();
        if (v >= lastVal){
          fail("values not decreasing");
        }
        lastVal = v;
      }
    }
  }
  
  @Test
  public void testReverse(){
    if (verifyNoPropertyViolation("+listener=.test.mc.basic.CGReorderTest$ReverseListener")){
      int x = Verify.getInt(0,4);
      System.out.println(x);
    }
  }

  
  public static class ReorderListener extends ListenerAdapter {
    ChoiceGenerator<?> reorderedCG;
    
    @Override
    public void choiceGeneratorRegistered (VM vm, ChoiceGenerator<?> nextCG, ThreadInfo ti, Instruction executedInsn){
      // make sure we are not getting recursive (could also use setId())
      if (nextCG instanceof DoubleChoiceFromList && nextCG != reorderedCG){ 
        System.out.println("reorder choices");
        reorderedCG = ((DoubleChoiceFromList)nextCG).reorder( new Comparator<Double>(){
          @Override
		public int compare (Double d1, Double d2){
            return (int) (d2 - d1);
          }
        });
        
        System.out.println("replacing: " + nextCG);
        System.out.println("with: " + reorderedCG);
        SystemState ss = vm.getSystemState();
        ss.removeNextChoiceGenerator();
        ss.setNextChoiceGenerator(reorderedCG);
      }
    }

    double lastVal = Double.MAX_VALUE;
    @Override
    public void choiceGeneratorAdvanced (VM vm, ChoiceGenerator<?> currentCG){
      if (currentCG instanceof DoubleChoiceGenerator){
        double v = ((DoubleChoiceGenerator)currentCG).getNextChoice();
        if (v >= lastVal){
          fail("values not decreasing");
        }
        lastVal = v;
      }
    }
  }
  
  @Test
  public void testReorder(){
    if (verifyNoPropertyViolation("+listener=.test.mc.basic.CGReorderTest$ReorderListener")){
      double x = Verify.getDoubleFromList(1.0, 2.0, 3.0, 4.0);
      System.out.println(x);
    }
  }
  
}