/*

 * Copyright (c) 2010, 2013, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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

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 */

package jdk.nashorn.internal.runtime.arrays;

import static jdk.nashorn.internal.codegen.CompilerConstants.specialCall;

import java.lang.invoke.MethodHandle;

import java.lang.invoke.MethodHandles;

import java.util.Arrays;

import jdk.nashorn.internal.runtime.JSType;

import jdk.nashorn.internal.runtime.ScriptRuntime;

/**

 * Implementation of {@link ArrayData} as soon as an int has been

 * written to the array. This is the default data for new arrays

 */

final class IntArrayData extends ContinuousArrayData implements IntElements {

    /**

     * The wrapped array

     */

    private int[] array;

    IntArrayData() {

        this(new int[ArrayData.CHUNK_SIZE], 0);

    }

    IntArrayData(final int length) {

        super(length);

        this.array  = new int[ArrayData.nextSize(length)];

    }

    /**

     * Constructor

     * @param array an int array

     * @param length a length, not necessarily array.length

     */

    IntArrayData(final int[] array, final int length) {

        super(length);

        assert array == null || array.length >= length;

        this.array = array;

    }

    @Override

    public final Class<?> getElementType() {

        return int.class;

    }

    @Override

    public final Class<?> getBoxedElementType() {

        return Integer.class;

    }

    @Override

    public final int getElementWeight() {

        return 1;

    }

    @Override

    public final ContinuousArrayData widest(final ContinuousArrayData otherData) {

        return otherData;

    }

    private static final MethodHandle HAS_GET_ELEM = specialCall(MethodHandles.lookup(), IntArrayData.class, "getElem", int.class, int.class).methodHandle();

    private static final MethodHandle SET_ELEM     = specialCall(MethodHandles.lookup(), IntArrayData.class, "setElem", void.class, int.class, int.class).methodHandle();

    @Override

    public Object[] asObjectArray() {

        return toObjectArray(true);

    }

    @SuppressWarnings("unused")

    private int getElem(final int index) {

        if (has(index)) {

            return array[index];

        }

        throw new ClassCastException();

    }

    @SuppressWarnings("unused")

    private void setElem(final int index, final int elem) {

        if (hasRoomFor(index)) {

            array[index] = elem;

            return;

        }

        throw new ClassCastException();

    }

    @Override

    public MethodHandle getElementGetter(final Class<?> returnType, final int programPoint) {

        return getContinuousElementGetter(HAS_GET_ELEM, returnType, programPoint);

    }

    @Override

    public MethodHandle getElementSetter(final Class<?> elementType) {

        return elementType == int.class ? getContinuousElementSetter(SET_ELEM, elementType) : null;

    }

    @Override

    public IntArrayData copy() {

        return new IntArrayData(array.clone(), (int)length());

    }

    @Override

    public Object asArrayOfType(final Class<?> componentType) {

        if (componentType == int.class) {

            final int len = (int)length();

            return array.length == len ? array.clone() : Arrays.copyOf(array, len);

        }

        return super.asArrayOfType(componentType);

    }

    private Object[] toObjectArray(final boolean trim) {

        assert length() <= array.length : "length exceeds internal array size";

        final int len = (int)length();

        final Object[] oarray = new Object[trim ? len : array.length];

        for (int index = 0; index < len; index++) {

            oarray[index] = array[index];

        }

        return oarray;

    }

    private double[] toDoubleArray() {

        assert length() <= array.length : "length exceeds internal array size";

        final int len = (int)length();

        final double[] darray = new double[array.length];

        for (int index = 0; index < len; index++) {

            darray[index] = array[index];

        }

        return darray;

    }

    private NumberArrayData convertToDouble() {

        return new NumberArrayData(toDoubleArray(), (int)length());

    }

    private ObjectArrayData convertToObject() {

        return new ObjectArrayData(toObjectArray(false), (int)length());

    }

    @Override

    public ArrayData convert(final Class<?> type) {

        if (type == Integer.class || type == Byte.class || type == Short.class) {

            return this;

        } else if (type == Double.class || type == Float.class) {

            return convertToDouble();

        } else {

            return convertToObject();

        }

    }

    @Override

    public ArrayData shiftLeft(final int by) {

        if (by >= length()) {

            shrink(0);

        } else {

            System.arraycopy(array, by, array, 0, array.length - by);

        }

        setLength(Math.max(0, length() - by));

        return this;

    }

    @Override

    public ArrayData shiftRight(final int by) {

        final ArrayData newData = ensure(by + length() - 1);

        if (newData != this) {

            newData.shiftRight(by);

            return newData;

        }

        System.arraycopy(array, 0, array, by, array.length - by);

        return this;

    }

    @Override

    public ArrayData ensure(final long safeIndex) {

        if (safeIndex >= SparseArrayData.MAX_DENSE_LENGTH) {

            return new SparseArrayData(this, safeIndex + 1);

        }

        final int alen = array.length;

        if (safeIndex >= alen) {

            final int newLength = ArrayData.nextSize((int)safeIndex);

            array = Arrays.copyOf(array, newLength);

        }

        if (safeIndex >= length()) {

            setLength(safeIndex + 1);

        }

        return this;

    }

    @Override

    public ArrayData shrink(final long newLength) {

        Arrays.fill(array, (int)newLength, array.length, 0);

        return this;

    }

    @Override

    public ArrayData set(final int index, final Object value, final boolean strict) {

        if (JSType.isRepresentableAsInt(value)) {

            return set(index, JSType.toInt32(value), strict);

        } else if (value == ScriptRuntime.UNDEFINED) {

            return new UndefinedArrayFilter(this).set(index, value, strict);

        }

        final ArrayData newData = convert(value == null ? Object.class : value.getClass());

        return newData.set(index, value, strict);

    }

    @Override

    public ArrayData set(final int index, final int value, final boolean strict) {

        array[index] = value;

        setLength(Math.max(index + 1, length()));

        return this;

    }

    @Override

    public ArrayData set(final int index, final double value, final boolean strict) {

        if (JSType.isRepresentableAsInt(value)) {

            array[index] = (int)(long)value;

            setLength(Math.max(index + 1, length()));

            return this;

        }

        return convert(Double.class).set(index, value, strict);

    }

    @Override

    public int getInt(final int index) {

        return array[index];

    }

    @Override

    public int getIntOptimistic(final int index, final int programPoint) {

        return array[index];

    }

    @Override

    public double getDouble(final int index) {

        return array[index];

    }

    @Override

    public double getDoubleOptimistic(final int index, final int programPoint) {

        return array[index];

    }

    @Override

    public Object getObject(final int index) {

        return array[index];

    }

    @Override

    public boolean has(final int index) {

        return 0 <= index && index < length();

    }

    @Override

    public ArrayData delete(final int index) {

        return new DeletedRangeArrayFilter(this, index, index);

    }

    @Override

    public ArrayData delete(final long fromIndex, final long toIndex) {

        return new DeletedRangeArrayFilter(this, fromIndex, toIndex);

    }

    @Override

    public Object pop() {

        final int len = (int)length();

        if (len == 0) {

            return ScriptRuntime.UNDEFINED;

        }

        final int newLength = len - 1;

        final int elem = array[newLength];

        array[newLength] = 0;

        setLength(newLength);

        return elem;

    }

    @Override

    public ArrayData slice(final long from, final long to) {

        return new IntArrayData(Arrays.copyOfRange(array, (int)from, (int)to), (int)(to - (from < 0 ? from + length() : from)));

    }

    @Override

    public ArrayData fastSplice(final int start, final int removed, final int added) throws UnsupportedOperationException {

        final long oldLength = length();

        final long newLength = oldLength - removed + added;

        if (newLength > SparseArrayData.MAX_DENSE_LENGTH && newLength > array.length) {

            throw new UnsupportedOperationException();

        }

        final ArrayData returnValue = removed == 0 ?

                EMPTY_ARRAY :

                new IntArrayData(

                        Arrays.copyOfRange(

                                array,

                                start,

                                start + removed),

                        removed);

        if (newLength != oldLength) {

            final int[] newArray;

            if (newLength > array.length) {

                newArray = new int[ArrayData.nextSize((int)newLength)];

                System.arraycopy(array, 0, newArray, 0, start);

            } else {

                newArray = array;

            }

            System.arraycopy(array, start + removed, newArray, start + added, (int)(oldLength - start - removed));

            array = newArray;

            setLength(newLength);

        }

        return returnValue;

    }

    @Override

    public double fastPush(final int arg) {

        final int len = (int)length();

        if (len == array.length) {

            array = Arrays.copyOf(array, nextSize(len));

        }

        array[len] = arg;

        return increaseLength();

    }

    //length must not be zero

    @Override

    public int fastPopInt() {

        if (length() == 0) {

            throw new ClassCastException(); //relink

        }

        final int newLength = (int)decreaseLength();

        final int elem = array[newLength];

        array[newLength] = 0;

        return elem;

    }

    @Override

    public double fastPopDouble() {

        return fastPopInt();

    }

    @Override

    public Object fastPopObject() {

        return fastPopInt();

    }

    @Override

    public ContinuousArrayData fastConcat(final ContinuousArrayData otherData) {

        final int   otherLength = (int)otherData.length();

        final int   thisLength  = (int)length();

        assert otherLength > 0 && thisLength > 0;

        final int[] otherArray  = ((IntArrayData)otherData).array;

        final int   newLength   = otherLength + thisLength;

        final int[] newArray    = new int[ArrayData.alignUp(newLength)];

        System.arraycopy(array, 0, newArray, 0, thisLength);

        System.arraycopy(otherArray, 0, newArray, thisLength, otherLength);

        return new IntArrayData(newArray, newLength);

    }

    @Override

    public String toString() {

        assert length() <= array.length : length() + " > " + array.length;

        return getClass().getSimpleName() + ':' + Arrays.toString(Arrays.copyOf(array, (int)length()));

    }

}