/**
 * Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite
 * contributors
 *
 * This file is part of EvoSuite.
 *
 * EvoSuite is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3.0 of the License, or
 * (at your option) any later version.
 *
 * EvoSuite is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
 */
package org.evosuite.assertion;

import java.util.HashSet;
import java.util.Set;

import org.evosuite.testcase.TestCase;
import org.evosuite.testcase.variable.VariableReference;
import org.evosuite.testcase.execution.CodeUnderTestException;
import org.evosuite.testcase.execution.Scope;

/**
 * Assertion on comparison value of two objects
 * 
 * @author Gordon Fraser
 */
public class CompareAssertion extends Assertion {

	private static final long serialVersionUID = 7415863202662602633L;

	protected VariableReference dest;

	/**
	 * <p>
	 * Getter for the field <code>dest</code>.
	 * </p>
	 * 
	 * @return a {@link org.evosuite.testcase.variable.VariableReference} object.
	 */
	public VariableReference getDest() {
		return dest;
	}

	/**
	 * <p>
	 * Setter for the field <code>dest</code>.
	 * </p>
	 * 
	 * @param dest
	 *            a {@link org.evosuite.testcase.variable.VariableReference} object.
	 */
	public void setDest(VariableReference dest) {
		this.dest = dest;
	}

	/**
	 * {@inheritDoc}
	 * 
	 * Create a copy of the compare assertion
	 */
	@Override
	public Assertion copy(TestCase newTestCase, int offset) {
		CompareAssertion s = new CompareAssertion();
		s.source = newTestCase.getStatement(source.getStPosition() + offset).getReturnValue();
		s.dest = newTestCase.getStatement(dest.getStPosition() + offset).getReturnValue();
		s.value = value;
		s.comment = comment;
		s.killedMutants.addAll(killedMutants);
		return s;
	}

	/**
	 * {@inheritDoc}
	 * 
	 * This method returns the Java Code
	 */
	@Override
	public String getCode() {
		if (source.getType().equals(Integer.class)) {
			if ((Integer) value == 0)
				return "assertTrue(" + source.getName() + " == " + dest.getName() + ");";
			else if ((Integer) value < 0)
				return "assertTrue(" + source.getName() + " < " + dest.getName() + ");";
			else
				return "assertTrue(" + source.getName() + " > " + dest.getName() + ");";

		} else {
			return "assertEquals(" + source.getName() + ".compareTo(" + dest.getName()
			        + "), " + value + ");";
		}
	}

	/**
	 * {@inheritDoc}
	 * 
	 * Determine if assertion holds in current scope
	 */
	@SuppressWarnings("unchecked")
	@Override
	public boolean evaluate(Scope scope) {
		try {
			Comparable<Object> comparable = (Comparable<Object>) source.getObject(scope);
			if (comparable == null)
				if ((Integer) value == 0)
					return dest.getObject(scope) == null;
				else
					return true; // TODO - true or false?
			else {
				try {
					return comparable.compareTo(dest.getObject(scope)) == (Integer) value;
				} catch (Exception e) {
					return true; // TODO - true or false?
				}
			}
		} catch (CodeUnderTestException e) {
			throw new UnsupportedOperationException();
		}
	}

	/** {@inheritDoc} */
	@Override
	public int hashCode() {
		final int prime = 31;
		int result = super.hashCode();
		result = prime * result + ((dest == null) ? 0 : dest.hashCode());
		return result;
	}

	/** {@inheritDoc} */
	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		CompareAssertion other = (CompareAssertion) obj;
		if (dest == null) {
			if (other.dest != null)
				return false;
		} else if (!dest.equals(other.dest))
			return false;
		if (source == null) {
			if (other.source != null)
				return false;
		} else if (!source.equals(other.source))
			return false;
		if (value == null) {
			if (other.value != null)
				return false;
		} else if ((Integer) value > 0) {
			if ((Integer) other.value <= 0)
				return false;
		} else if ((Integer) value < 0) {
			if ((Integer) other.value >= 0)
				return false;
		} else if ((Integer) value == 0) {
			if ((Integer) other.value != 0)
				return false;
		}
		return true;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.evosuite.assertion.Assertion#getReferencedVariables()
	 */
	/** {@inheritDoc} */
	@Override
	public Set<VariableReference> getReferencedVariables() {
		Set<VariableReference> vars = new HashSet<VariableReference>();
		vars.add(source);
		vars.add(dest);
		return vars;
	}

	/* (non-Javadoc)
	 * @see org.evosuite.assertion.Assertion#isValid()
	 */
	/** {@inheritDoc} */
	@Override
	public boolean isValid() {
		return super.isValid() && dest != null;
	}

}