/*

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.sun.org.apache.xerces.internal.util;

import com.sun.org.apache.xerces.internal.xni.Augmentations;

import java.util.Collections;

import java.util.Enumeration;

import java.util.HashMap;

import java.util.Map;

/**

 * This class provides an implementation for Augmentations interface.

 * Augmentations interface defines a map of additional data that could

 * be passed along the document pipeline. The information can contain extra

 * arguments or infoset augmentations, for example PSVI. This additional

 * information is identified by a String key.

 * <p>

 *

 * @author Elena Litani, IBM

 */

public class AugmentationsImpl implements Augmentations{

    private AugmentationsItemsContainer fAugmentationsContainer =

                                        new SmallContainer();

    /**

     * Add additional information identified by a key to the Augmentations structure.

     *

     * @param key    Identifier, can't be <code>null</code>

     * @param item   Additional information

     *

     * @return the previous value of the specified key in the Augmentations strucutre,

     *         or <code>null</code> if it did not have one.

     */

    public Object putItem (String key, Object item){

        Object oldValue = fAugmentationsContainer.putItem(key, item);

        if (oldValue == null && fAugmentationsContainer.isFull()) {

            fAugmentationsContainer = fAugmentationsContainer.expand();

        }

        return oldValue;

    }

    /**

     * Get information identified by a key from the Augmentations structure

     *

     * @param key    Identifier, can't be <code>null</code>

     *

     * @return the value to which the key is mapped in the Augmentations structure;

     *         <code>null</code> if the key is not mapped to any value.

     */

    public Object getItem(String key){

        return fAugmentationsContainer.getItem(key);

    }

    /**

     * Remove additional info from the Augmentations structure

     *

     * @param key    Identifier, can't be <code>null</code>

     */

    public Object removeItem (String key){

        return fAugmentationsContainer.removeItem(key);

    }

    /**

     * Returns an enumeration of the keys in the Augmentations structure

     *

     */

        return fAugmentationsContainer.keys();

    }

    /**

     * Remove all objects from the Augmentations structure.

     */

    public void removeAllItems() {

        fAugmentationsContainer.clear();

    }

    public String toString() {

        return fAugmentationsContainer.toString();

    }

    abstract class AugmentationsItemsContainer {

        abstract public Object putItem(Object key, Object item);

        abstract public Object getItem(Object key);

        abstract public Object removeItem(Object key);

        abstract public void clear();

        abstract public boolean isFull();

        abstract public AugmentationsItemsContainer expand();

    }

    class SmallContainer extends AugmentationsItemsContainer {

        final static int SIZE_LIMIT = 10;

        final Object[] fAugmentations = new Object[SIZE_LIMIT*2];

        int fNumEntries = 0;

            return new SmallContainerKeyEnumeration();

        }

        public Object getItem(Object key) {

            for (int i = 0; i < fNumEntries*2; i = i + 2) {

                if (fAugmentations[i].equals(key)) {

                    return fAugmentations[i+1];

                }

            }

            return null;

        }

        public Object putItem(Object key, Object item) {

            for (int i = 0; i < fNumEntries*2; i = i + 2) {

                if (fAugmentations[i].equals(key)) {

                    Object oldValue = fAugmentations[i+1];

                    fAugmentations[i+1] = item;

                    return oldValue;

                }

            }

            fAugmentations[fNumEntries*2] = key;

            fAugmentations[fNumEntries*2+1] = item;

            fNumEntries++;

            return null;

        }

        public Object removeItem(Object key) {

            for (int i = 0; i < fNumEntries*2; i = i + 2) {

                if (fAugmentations[i].equals(key)) {

                    Object oldValue = fAugmentations[i+1];

                    for (int j = i; j < fNumEntries*2 - 2; j = j + 2) {

                        fAugmentations[j] = fAugmentations[j+2];

                        fAugmentations[j+1] = fAugmentations[j+3];

                    }

                    fAugmentations[fNumEntries*2-2] = null;

                    fAugmentations[fNumEntries*2-1] = null;

                    fNumEntries--;

                    return oldValue;

                }

            }

            return null;

        }

        public void clear() {

            for (int i = 0; i < fNumEntries*2; i = i + 2) {

                fAugmentations[i] = null;

                fAugmentations[i+1] = null;

            }

            fNumEntries = 0;

        }

        public boolean isFull() {

            return (fNumEntries == SIZE_LIMIT);

        }

        public AugmentationsItemsContainer expand() {

            LargeContainer expandedContainer = new LargeContainer();

            for (int i = 0; i < fNumEntries*2; i = i + 2) {

                expandedContainer.putItem(fAugmentations[i],

                                          fAugmentations[i+1]);

            }

            return expandedContainer;

        }

        public String toString() {

            StringBuilder buff = new StringBuilder();

            buff.append("SmallContainer - fNumEntries == ").append(fNumEntries);

            for (int i = 0; i < SIZE_LIMIT*2; i=i+2) {

                buff.append("\nfAugmentations[")

                    .append(i)

                    .append("] == ")

                    .append(fAugmentations[i])

                    .append("; fAugmentations[")

                    .append(i+1)

                    .append("] == ")

                    .append(fAugmentations[i+1]);

            }

            return buff.toString();

        }

            Object [] enumArray = new Object[fNumEntries];

            int next = 0;

            SmallContainerKeyEnumeration() {

                for (int i = 0; i < fNumEntries; i++) {

                    enumArray[i] = fAugmentations[i*2];

                }

            }

            public boolean hasMoreElements() {

                return next < enumArray.length;

            }

            public Object nextElement() {

                if (next >= enumArray.length) {

                    throw new java.util.NoSuchElementException();

                }

                Object nextVal = enumArray[next];

                enumArray[next] = null;

                next++;

                return nextVal;

            }

        }

    }

    class LargeContainer extends AugmentationsItemsContainer {

        final Map<Object, Object> fAugmentations = new HashMap<>();

        public Object getItem(Object key) {

            return fAugmentations.get(key);

        }

        public Object putItem(Object key, Object item) {

            return fAugmentations.put(key, item);

        }

        public Object removeItem(Object key) {

            return fAugmentations.remove(key);

        }

            return Collections.enumeration(fAugmentations.keySet());

        }

        public void clear() {

            fAugmentations.clear();

        }

        public boolean isFull() {

            return false;

        }

        public AugmentationsItemsContainer expand() {

            return this;

        }

        public String toString() {

            StringBuilder buff = new StringBuilder();

            buff.append("LargeContainer");

            for(Object key : fAugmentations.keySet()) {

                buff.append("\nkey == ");

                buff.append(key);

                buff.append("; value == ");

                buff.append(fAugmentations.get(key));

            }

            return buff.toString();

        }

    }

}