/*
 * Copyright (c) 2007, 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.sun.max.asm.gen.risc.bitRange;

import java.util.*;

/**
 * A range of bits that is composed of several disjoint subranges.
 */

public class CompoundBitRange extends BitRange {

    public CompoundBitRange() {
        super();
    }

    private List<ContiguousBitRange> contiguousBitRanges = new ArrayList<>();

    public List<ContiguousBitRange> contiguousBitRanges() {
        return contiguousBitRanges;
    }

    public void add(ContiguousBitRange contiguousBitRange) {
        contiguousBitRanges.add(contiguousBitRange);
    }

    @Override
    public CompoundBitRange move(boolean left, int bits) {
        final CompoundBitRange movedRange = new CompoundBitRange();
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            movedRange.add((ContiguousBitRange) contiguousBitRange.move(left, bits));
        }
        return movedRange;
    }

    @Override
    public int width() {
        int result = 0;
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            result += contiguousBitRange.width();
        }
        return result;
    }

    @Override
    public int encodedWidth() {
        int result = 0;
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            result += contiguousBitRange.encodedWidth();
        }
        return result;
    }

    @Override
    public int instructionMask() {
        int mask = 0;
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            mask |= contiguousBitRange.instructionMask();
        }
        return mask;
    }

    @Override
    public int numberOfLessSignificantBits() {
        int result = 32;
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            final int n = contiguousBitRange.numberOfLessSignificantBits();
            if (n < result) {
                result = n;
            }
        }
        return result;
    }

    @Override
    public boolean equals(Object other) {
        if (!(other instanceof CompoundBitRange)) {
            return false;
        }
        final CompoundBitRange compoundBitRange = (CompoundBitRange) other;
        return contiguousBitRanges.equals(compoundBitRange.contiguousBitRanges);
    }

    @Override
    public int hashCode() {
        return contiguousBitRanges.hashCode();
    }

    @Override
    public String toString() {
        String result = null;
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            if (result != null) {
                result += "," + contiguousBitRange;
            } else {
                result = contiguousBitRange.toString();
            }
        }
        return result;
    }

    /* Extracting */

    @Override
    public int extractSignedInt(int instruction) {
        final Iterator<ContiguousBitRange> iterator = contiguousBitRanges.iterator();
        final ContiguousBitRange firstBitRange = iterator.next();
        int signedInt = firstBitRange.extractSignedInt(instruction);
        while (iterator.hasNext()) {
            final ContiguousBitRange contiguousBitRange = iterator.next();
            signedInt <<= contiguousBitRange.width();
            signedInt |= contiguousBitRange.extractUnsignedInt(instruction);
        }
        return signedInt;
    }

    @Override
    public int extractUnsignedInt(int instruction) {
        int unsignedInt = 0;
        for (ContiguousBitRange contiguousBitRange : contiguousBitRanges) {
            unsignedInt <<= contiguousBitRange.width();
            unsignedInt |= contiguousBitRange.extractUnsignedInt(instruction);
        }
        return unsignedInt;
    }

    /* Inserting */

    @Override
    public int assembleUncheckedSignedInt(int signedInt) throws IndexOutOfBoundsException {
        int value = signedInt;
        int result = 0;
        for (int i = contiguousBitRanges.size() - 1; i >= 0; i--) {
            final ContiguousBitRange contiguousBitRange = contiguousBitRanges.get(i);
            result |= contiguousBitRange.assembleUncheckedSignedInt(value);
            value >>= contiguousBitRange.width();
        }
        return result;
    }

    @Override
    public int assembleUncheckedUnsignedInt(int unsignedInt) throws IndexOutOfBoundsException {
        int value = unsignedInt;
        int result = 0;
        for (int i = contiguousBitRanges.size() - 1; i >= 0; i--) {
            final ContiguousBitRange contiguousBitRange = contiguousBitRanges.get(i);
            result |= contiguousBitRange.assembleUncheckedUnsignedInt(value);
            value >>>= contiguousBitRange.width();
        }
        return result;
    }

    @Override
    public String encodingString(String value, boolean signed, boolean checked) {
        final StringBuilder sb = new StringBuilder();
        int shift = 0;
        for (int i = contiguousBitRanges.size() - 1; i >= 0; i--) {
            final ContiguousBitRange contiguousBitRange = contiguousBitRanges.get(i);
            final String bits = (shift == 0) ? value : "(" + value + (signed ? " >> " : " >>> ") + shift + ")";
            final String encoding = contiguousBitRange.encodingString(bits, signed, false);
            if (encoding.length() != 0) {
                if (sb.length() != 0) {
                    sb.append(" | ");
                }
                sb.append(encoding);
            }
            shift += contiguousBitRange.width();
        }
        return sb.toString();
    }
}