package lawOfDemeter;

import java.util.*;

/**
 * The Checker aspect is part of a Law of Demeter Checker - a set of
 * classes and aspects that verify a given program does not violate
 * the Law of Demeter.  This aspect verifies that method calls do not
 * violate the Law of Demeter.
 *
 * @author David H. Lorenz
 * @author Modifications made by Paul Freeman
 */

public aspect Checker {

  // statistcs variables
  private long totalChecks = 0;
  private long numViolations = 0;
  private Vector validChecks = new Vector();  // position 0 = total valid checks
                                              // position i = total valid checks where
                                              //              i = num of matches perCheck

  /**
   * Advice that does the checking.
   */
  before():
    (Any.MethodCall() || Any.Get()) && Any.ToAvoid(){
      Object thisObj = thisJoinPoint.getThis();
      Object target = thisJoinPoint.getTarget();
      Vector suppliers = new Vector();
      int binCount = 0;

     System.out.println("Checking--" + thisJoinPoint + JPUtil.at(thisJoinPoint));
      totalChecks++;

      // get the global "Bin" objects
      suppliers.add( ArgumentBin.aspectOf() );
      suppliers.add( LocallyConstructedBin.aspectOf() );
      suppliers.add( ReturnValueBin.aspectOf() );
      suppliers.add( GlobalPreferredBin.aspectOf() );

      // get the "Bin" objects associated with the currently executing object (this)
      try{
      // this needs to be "tried" as there might NOT be an aspect associated with this obj
        suppliers.add( ImmediatePartBin.aspectOf(thisObj) );
//        ImmediatePartBin.aspectOf(thisObj).printBin();
      }catch(org.aspectj.lang.NoAspectBoundException e){
      }

//      ArgumentBin.aspectOf().printAllBins();
//      LocallyConstructedBin.aspectOf().printAllBins();
//      ReturnValueBin.aspectOf().printAllBins();

      //check if target is in any of the bins
      boolean isInBin = false;
      Iterator supIt = suppliers.iterator();
      while(supIt.hasNext()){
        Supplier thisBin = (Supplier)supIt.next();
        if(thisBin.contains(target)){
          isInBin = true;
          binCount++;
        }
      }

      if (!isInBin){
      // if the target is not a preferred supplier -> Violation
        numViolations++;
        System.out.println("!! LoD violation: " + thisJoinPoint +
          JPUtil.at(thisJoinPoint));
      }else{
        addToStats(binCount);
      }
  }

  // Keeps track of the valid count statistics
  private void addToStats(int binCount){
    //initialize count being increased if necessary
    try{
      if(validChecks.elementAt(0) == null);
    }catch(java.lang.ArrayIndexOutOfBoundsException e){
      validChecks.setSize(1);
      validChecks.setElementAt(new Long(0), 0);  // total count
    }
    try{
      if(validChecks.elementAt(binCount) == null);
    }catch(java.lang.ArrayIndexOutOfBoundsException e){
      validChecks.setSize(binCount + 1);
      validChecks.setElementAt(new Long(0), binCount);
    }

    // increase counts
    Long val;
    val = new Long(((Long)validChecks.elementAt(0)).longValue() + 1);
    validChecks.setElementAt(val, 0);
    val = new Long(((Long)validChecks.elementAt(binCount)).longValue() + 1);
    validChecks.setElementAt(val, binCount);
  }

  // prints statistics when program is done executing
  after():
    Any.MainMethodExecution(){
      long totalValid = 0;
      try{
        totalValid = ((Long)validChecks.elementAt(0)).longValue();
      }catch(java.lang.ArrayIndexOutOfBoundsException e){
      }

      System.out.println("\nStatistics:");
      System.out.println("Type        \t\tCount\tValid%\tTotal%");
      System.out.println("Total Checks\t\t" + totalChecks);
      System.out.println("Violations  \t\t" + numViolations +
        "\t"+ fix((double)numViolations/(double)totalValid * 100, 2) +
        "\t"+ fix((double)numViolations/(double)totalChecks * 100, 2));

      for(int i = 0; i < validChecks.size(); i++){
        String type = "";
        if(i==0){type = "Valid Checks";}
        else if(i==1){type = "As "+i+" Supplier";}
        else{type = "As "+i+" Suppliers";}

        long thisCount = ((Long)validChecks.elementAt(i)).longValue();
        System.out.println(type + "\t\t" + thisCount +
          "\t"+ fix((double)thisCount/(double)totalValid * 100, 2) +
          "\t"+ fix((double)thisCount/(double)totalChecks * 100, 2));
      }
  }

  // fixes a double to a certain number of decimal places
  private double fix(double aDouble, int numDec){
    try{
      String d = new String(new Double(aDouble).toString());
      int dotPos = d.indexOf('.');
      int len = d.length();
      int lastPos = dotPos + numDec + 1;
      if(lastPos > len){lastPos = len;}
      return new Double(d.substring(0, lastPos)).doubleValue();
    }catch(java.lang.NumberFormatException e){
      return 0;
    }
  }
}