/*
 * Copyright 2009 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

/**
 * @test
 * @bug 4504839
 * @summary Basic tests for unsigned operations
 * @author Joseph D. Darcy
 */

import java.math.*;

public class Unsigned {
    public static void main(String... args) {
        int errors = 0;

        errors += testUnsignedCompare();

        if (errors > 0) {
            throw new RuntimeException(errors + "errors found in unsigned operations.");
        }
    }

    private static int testUnsignedCompare() {
        int errors = 0;
        
        long[] data = {
            0L,
            1L,
            2L,
            3L,
            0x00000000_80000000L,
            0x00000000_FFFFFFFFL,
            0x00000001_00000000L,
            0x80000000_00000000L,
            0x80000000_00000001L,
            0x80000000_00000002L,
            0x80000000_00000003L,
            0x80000000_80000000L,
            0xFFFFFFFF_FFFFFFFEL,
            0xFFFFFFFF_FFFFFFFFL,
        };

        for(long i : data) {
            for(long j : data) {
                long libraryResult    = Long.compareUnsigned(i, j);
                long libraryResultRev = Long.compareUnsigned(j, i);
                long localResult      = compUnsigned(i, j);
                
                if (i == j) {
                    if (libraryResult != 0) {
                        errors++;
                        System.err.printf("Value 0x%x did not compare as " +
                                          "an unsigned equal to itself; got %d%n",
                                          i, libraryResult);
                    }
                }

                   if (Long.signum(libraryResult) != Long.signum(localResult)) {
                       errors++;
                       System.err.printf("Unsigned compare of 0x%x to 0x%x%n:" +
                                         "\texpected sign of %d, got %d%n",
                                         i, j, localResult, libraryResult);
                   }

                if (Long.signum(libraryResult) !=
                    -Long.signum(libraryResultRev)) {
                    errors++;
                    System.err.printf("unsgnCmp(x, y) != - unsignedComp(y,x) for" +
                                      "\t0x%x and 0x%x, computed %d and %d%n",
                                      i, j, libraryResult, libraryResultRev);
                }
            }
        }

        return errors;
    }

    private static int compUnsigned(long x, long y) {
        BigInteger big_x = toUnsignedBigInt(x);
        BigInteger big_y = toUnsignedBigInt(y);

        return big_x.compareTo(big_y);
    }

    private static BigInteger toUnsignedBigInt(long x) {
        if (x >= 0)
            return BigInteger.valueOf(x);
        else {
            int upper = (int)(((long)x) >> 32);
            int lower = (int) x;

            BigInteger bi = // (upper << 32) + lower
                (BigInteger.valueOf(Integer.toUnsignedLong(upper))).shiftLeft(32).
                add(BigInteger.valueOf(Integer.toUnsignedLong(lower)));

            System.out.printf("%n\t%d%n\t%s%n", x, bi.toString());
            return bi; // TODO
        }
    }
}