SnapshotSelectorModel.java

/*
 * Copyright (C) 2010 Brockmann Consult GmbH (info@brockmann-consult.de)
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 3 of the License, or (at your option)
 * any later version.
 * This program 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 for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, see http://www.gnu.org/licenses/
 */
package org.esa.beam.smos.visat.swing;

import javax.swing.BoundedRangeModel;
import javax.swing.DefaultBoundedRangeModel;
import javax.swing.SpinnerListModel;
import javax.swing.SpinnerModel;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.PlainDocument;
import java.text.MessageFormat;
import java.util.Collections;
import java.util.List;

class SnapshotSelectorModel {
    private final SpinnerListModel spinnerModel;
    private final BoundedRangeModel sliderModel;
    private final PlainDocument sliderInfoDocument;

    SnapshotSelectorModel(List<Long> snapshotIds) {
        spinnerModel = new SpinnerListModel(snapshotIds);
        sliderModel = new DefaultBoundedRangeModel(0, 0, 0, snapshotIds.size() - 1);
        sliderInfoDocument = new PlainDocument();

        spinnerModel.addChangeListener(new ChangeListener() {
            @Override
            public void stateChanged(ChangeEvent e) {
                final int sliderValue = Collections.binarySearch(getSpinnerModelList(), spinnerModel.getValue());
                sliderModel.setValue(sliderValue);
            }
        });
        sliderModel.addChangeListener(new ChangeListener() {
            @Override
            public void stateChanged(ChangeEvent e) {
                updateSliderInfoDocument();
                final Object spinnerValue = getSpinnerModelList().get(sliderModel.getValue());
                spinnerModel.setValue(spinnerValue);
            }
        });
        updateSliderInfoDocument();
    }

    /**
     * Returns the current snapshot ID.
     *
     * @return the current snapshot ID.
     */
    long getSnapshotId() {
        return (Long) spinnerModel.getValue();
    }

    /**
     * Sets the current snapshot ID to a new value.
     *
     * @param id the new snapshot ID.
     *
     * @throws IllegalArgumentException if the specified ID isn't allowed
     */
    void setSnapshotId(long id) {
        spinnerModel.setValue(id);
    }

    SpinnerModel getSpinnerModel() {
        return spinnerModel;
    }

    BoundedRangeModel getSliderModel() {
        return sliderModel;
    }

    Document getSliderInfoDocument() {
        return sliderInfoDocument;
    }

    // the cast made herein is safe by construction of the {@code spinnerModel}
    @SuppressWarnings({"unchecked"})
    private List<? extends Comparable<? super Object>> getSpinnerModelList() {
        return (List<? extends Comparable<? super Object>>) spinnerModel.getList();
    }

    private void updateSliderInfoDocument() {
        final String text = createSliderInfoText(sliderModel);
        try {
            sliderInfoDocument.replace(0, sliderInfoDocument.getLength(), text, null);
        } catch (BadLocationException e) {
            // cannot happen since the position within the document is always valid
            throw new IllegalStateException(e.getMessage(), e);
        }
    }

    private static String createSliderInfoText(BoundedRangeModel sliderModel) {
        return MessageFormat.format("{0} / {1}", sliderModel.getValue() + 1, sliderModel.getMaximum() + 1);
    }
}