/*

 * Copyright (c) 2000, 2014, 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 javax.swing;

import java.util.*;

import java.io.Serializable;

/**

 * A simple implementation of <code>SpinnerModel</code> whose

 * values are defined by an array or a <code>List</code>.

 * For example to create a model defined by

 * an array of the names of the days of the week:

 * <pre>

 * String[] days = new DateFormatSymbols().getWeekdays();

 * SpinnerModel model = new SpinnerListModel(Arrays.asList(days).subList(1, 8));

 * </pre>

 * This class only stores a reference to the array or <code>List</code>

 * so if an element of the underlying sequence changes, it's up

 * to the application to notify the <code>ChangeListeners</code> by calling

 * <code>fireStateChanged</code>.

 * <p>

 * This model inherits a <code>ChangeListener</code>.

 * The <code>ChangeListener</code>s are notified whenever the

 * model's <code>value</code> or <code>list</code> properties changes.

 *

 * @see JSpinner

 * @see SpinnerModel

 * @see AbstractSpinnerModel

 * @see SpinnerNumberModel

 * @see SpinnerDateModel

 *

 * @author Hans Muller

 * @since 1.4

 */

@SuppressWarnings("serial") // Superclass is not serializable across versions

public class SpinnerListModel extends AbstractSpinnerModel implements Serializable

{

    private List list;

    private int index;

    /**

     * Constructs a <code>SpinnerModel</code> whose sequence of

     * values is defined by the specified <code>List</code>.

     * The initial value (<i>current element</i>)

     * of the model will be <code>values.get(0)</code>.

     * If <code>values</code> is <code>null</code> or has zero

     * size, an <code>IllegalArugmentException</code> is thrown.

     *

     * @param values the sequence this model represents

     * @throws IllegalArgumentException if <code>values</code> is

     *    <code>null</code> or zero size

     */

    public SpinnerListModel(List<?> values) {

        if (values == null || values.size() == 0) {

            throw new IllegalArgumentException("SpinnerListModel(List) expects non-null non-empty List");

        }

        this.list = values;

        this.index = 0;

    }

    /**

     * Constructs a <code>SpinnerModel</code> whose sequence of values

     * is defined by the specified array.  The initial value of the model

     * will be <code>values[0]</code>.  If <code>values</code> is

     * <code>null</code> or has zero length, an

     * <code>IllegalArgumentException</code> is thrown.

     *

     * @param values the sequence this model represents

     * @throws IllegalArgumentException if <code>values</code> is

     *    <code>null</code> or zero length

     */

    public SpinnerListModel(Object[] values) {

        if (values == null || values.length == 0) {

            throw new IllegalArgumentException("SpinnerListModel(Object[]) expects non-null non-empty Object[]");

        }

        this.list = Arrays.asList(values);

        this.index = 0;

    }

    /**

     * Constructs an effectively empty <code>SpinnerListModel</code>.

     * The model's list will contain a single

     * <code>"empty"</code> string element.

     */

    public SpinnerListModel() {

        this(new Object[]{"empty"});

    }

    /**

     * Returns the <code>List</code> that defines the sequence for this model.

     *

     * @return the value of the <code>list</code> property

     * @see #setList

     */

    public List<?> getList() {

        return list;

    }

    /**

     * Changes the list that defines this sequence and resets the index

     * of the models <code>value</code> to zero.  Note that <code>list</code>

     * is not copied, the model just stores a reference to it.

     * <p>

     * This method fires a <code>ChangeEvent</code> if <code>list</code> is

     * not equal to the current list.

     *

     * @param list the sequence that this model represents

     * @throws IllegalArgumentException if <code>list</code> is

     *    <code>null</code> or zero length

     * @see #getList

     */

    public void setList(List<?> list) {

        if ((list == null) || (list.size() == 0)) {

            throw new IllegalArgumentException("invalid list");

        }

        if (!list.equals(this.list)) {

            this.list = list;

            index = 0;

            fireStateChanged();

        }

    }

    /**

     * Returns the current element of the sequence.

     *

     * @return the <code>value</code> property

     * @see SpinnerModel#getValue

     * @see #setValue

     */

    public Object getValue() {

        return list.get(index);

    }

    /**

     * Changes the current element of the sequence and notifies

     * <code>ChangeListeners</code>.  If the specified

     * value is not equal to an element of the underlying sequence

     * then an <code>IllegalArgumentException</code> is thrown.

     * In the following example the <code>setValue</code> call

     * would cause an exception to be thrown:

     * <pre>

     * String[] values = {"one", "two", "free", "four"};

     * SpinnerModel model = new SpinnerListModel(values);

     * model.setValue("TWO");

     * </pre>

     *

     * @param elt the sequence element that will be model's current value

     * @throws IllegalArgumentException if the specified value isn't allowed

     * @see SpinnerModel#setValue

     * @see #getValue

     */

    public void setValue(Object elt) {

        int index = list.indexOf(elt);

        if (index == -1) {

            throw new IllegalArgumentException("invalid sequence element");

        }

        else if (index != this.index) {

            this.index = index;

            fireStateChanged();

        }

    }

    /**

     * Returns the next legal value of the underlying sequence or

     * <code>null</code> if value is already the last element.

     *

     * @return the next legal value of the underlying sequence or

     *     <code>null</code> if value is already the last element

     * @see SpinnerModel#getNextValue

     * @see #getPreviousValue

     */

    public Object getNextValue() {

        return (index >= (list.size() - 1)) ? null : list.get(index + 1);

    }

    /**

     * Returns the previous element of the underlying sequence or

     * <code>null</code> if value is already the first element.

     *

     * @return the previous element of the underlying sequence or

     *     <code>null</code> if value is already the first element

     * @see SpinnerModel#getPreviousValue

     * @see #getNextValue

     */

    public Object getPreviousValue() {

        return (index <= 0) ? null : list.get(index - 1);

    }

    /**

     * Returns the next object that starts with <code>substring</code>.

     *

     * @param substring the string to be matched

     * @return the match

     */

    Object findNextMatch(String substring) {

        int max = list.size();

        if (max == 0) {

            return null;

        }

        int counter = index;

        do {

            Object value = list.get(counter);

            String string = value.toString();

            if (string != null && string.startsWith(substring)) {

                return value;

            }

            counter = (counter + 1) % max;

        } while (counter != index);

        return null;

    }

}