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 * compliance with the License.

 *

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 * or http://www.netbeans.org/cddl.txt.

 *

 * When distributing Covered Code, include this CDDL Header Notice in each file

 * and include the License file at http://www.netbeans.org/cddl.txt.

 * If applicable, add the following below the CDDL Header, with the fields

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 * "Portions Copyrighted [year] [name of copyright owner]"

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 * The Original Software is NetBeans. The Initial Developer of the Original

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 * Microsystems, Inc. All Rights Reserved.

 */

package org.netbeans.apifest.boolcircuit;

import java.util.Arrays;

import java.util.Stack;

import junit.framework.TestCase;

/** The initial quest for this APIFest is to create an API for boolean 

 * circuits. Such API shall be able to compose a boolean circuit from

 * basic elements and evaluate the result given initial values for 

 * input variables.

 * <p>

 * The basic elements include:

 * <ul>

 *   <li>negation - has one input and one output and changes 0 on input to 

 *          on output 1 and 1 to 0

 *   <li>and - has two inputs and one output. The output is 1 only if both 

 *          inputs are 1, otherwise it is 0

 *   <li>or - has two inputs and one output. The output is 1 always, except

 *          in the case when both inputs are 0

 * </ul>

 *

 * <p>

 * The boolean circuit can be used to represent boolean formulas and compute

 * the results for certain values of its inputs. The individual tasks described

 * as tests bellow.

 *

 * <p>

 * Links of interest:

 * <ul>

 *   <li><a href="http://en.wikipedia.org/wiki/Truth_table">Truth table</a>

 *   <li><a href="http://en.wikipedia.org/wiki/Tautology_(logic)">Taugology</a>

 * </ul>

 */

public class CircuitTest extends TestCase {

    static {

        // your code shall run without any permissions

    }

    public CircuitTest(String testName) {

        super(testName);

    }

    protected void setUp() throws Exception {

    }

    protected void tearDown() throws Exception {

    }

    // BEGIN: apifest.day1.stackbasedsolution.CircuitTest

    /** 

     * Create a circuit to evaluate x1 and x2 and then

     * verify that its result is false for input (false, true) and

     * it is true for input (true, true).

     */

    public void testX1andX2() {

        Stack<Character> s = new Stack<Character> ();

        s.addAll(Arrays.asList('1', '1'));

        assertEquals("'1' for '11' input.", '1', 

            CircuitFactory.getBasicCircuit(Operation.AND).evaluate(s));

        s.addAll(Arrays.asList('1', '0'));

        assertEquals("'0' for '10' input.", '0', 

            CircuitFactory.getBasicCircuit(Operation.AND).evaluate(s));

    }

    /** 

     * Create a circuit to evaluate (x1 and x2) or x3 and then

     * verify that its result is false for input (false, true, false) and

     * it is true for input (false, false, true).

     */

    public void testX1andX2orX3() {

        Stack<Character> s = new Stack<Character> ();

        s.addAll(Arrays.asList('0', '1', '0'));

        assertEquals("'0' for '010' input.", '0', 

            CircuitFactory.join(CircuitFactory.getTrivialCircuit(), 

            CircuitFactory.getBasicCircuit(Operation.OR), 

            Operation.AND).evaluate(s)

        );

        s.addAll(Arrays.asList('0', '0', '1'));

        assertEquals("'1' for '001' input.", '1', 

            CircuitFactory.join(CircuitFactory.getTrivialCircuit(), 

            CircuitFactory.getBasicCircuit(Operation.OR), 

            Operation.AND).evaluate(s)

        );

    }

    /** 

     * Create a circuit to evaluate (x1 or not(x1)) and then

     * verify that its result is true for all values of x1.

     */

    public void testAlwaysTrue() {

        Circuit alwaysTrue = CircuitFactory.join(

            CircuitFactory.getTrivialCircuit(), 

            CircuitFactory.getBasicCircuit(Operation.NEG), 

            Operation.OR

        );

        Stack<Character> s = new Stack<Character> ();

        s.addAll(Arrays.asList('0', '0'));

        assertEquals ("'1' for '00'", '1', alwaysTrue.evaluate(s));

        s.addAll(Arrays.asList('1', '1'));

        assertEquals ("'1' for '11'", '1', alwaysTrue.evaluate(s));

    }

    // END: apifest.day1.stackbasedsolution.CircuitTest

}