package kg.apc.jmeter.functions;

 import org.apache.commons.codec.binary.Base64;

 import org.apache.jmeter.engine.util.CompoundVariable;

 import org.apache.jmeter.functions.AbstractFunction;

 import org.apache.jmeter.functions.InvalidVariableException;

 import org.apache.jmeter.samplers.SampleResult;

 import org.apache.jmeter.samplers.Sampler;

 import org.apache.jmeter.threads.JMeterVariables;

 import java.util.Collection;

 import java.util.LinkedList;

 import java.util.List;

 public class Base64Decode extends AbstractFunction {

     private static final List<String> desc = new LinkedList<String>();

     private static final String KEY = "__base64Decode";

     // Number of parameters expected - used to reject invalid calls

     private static final int MIN_PARAMETER_COUNT = 1;

     private static final int MAX_PARAMETER_COUNT = 2;

     static {

         desc.add("Base64 string to be decoded");

         desc.add("Name of variable in which to store the result (optional)");

     }

     private CompoundVariable[] values;

     @Override

     public synchronized String execute(SampleResult previousResult, Sampler currentSampler)

             throws InvalidVariableException {

         String sourceString = values[0].execute();

         String decodedValue = new String(Base64.decodeBase64(sourceString));

         if (values.length > 1) {

             String variableName = values[1].execute();

             if (variableName.length() > 0) {// Allow for empty name

                 final JMeterVariables variables = getVariables();

                 if (variables != null) {

                     variables.put(variableName, decodedValue);

                 }

             }

         }

         return decodedValue;

     }

     @Override

     public synchronized void setParameters(Collection<CompoundVariable> parameters) throws InvalidVariableException {

         checkParameterCount(parameters, MIN_PARAMETER_COUNT, MAX_PARAMETER_COUNT);

         values = parameters.toArray(new CompoundVariable[parameters.size()]);

     }

     @Override

     public String getReferenceKey() {

         return KEY;

     }

     @Override

     public List<String> getArgumentDesc() {

         return desc;

     }

 }