FiltersManager.java

package org.openstreetmap.josm.plugins.rasterfilters.model;

import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.image.BufferedImage;
import java.rmi.server.UID;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;

import javax.json.JsonArray;
import javax.json.JsonObject;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JPanel;
import javax.swing.JSlider;

import com.bric.swing.ColorPicker;
import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.gui.layer.ImageProcessor;
import org.openstreetmap.josm.plugins.rasterfilters.filters.Filter;
import org.openstreetmap.josm.plugins.rasterfilters.gui.FilterGuiListener;
import org.openstreetmap.josm.plugins.rasterfilters.gui.FilterPanel;
import org.openstreetmap.josm.plugins.rasterfilters.gui.FiltersDialog;
import org.openstreetmap.josm.plugins.rasterfilters.preferences.FiltersDownloader;


/**
 * This class adds filter to the dialog and can also remove
 * or disable it from the filters chain.
 *
 * @author Nipel-Crumple
 */
public class FiltersManager implements StateChangeListener, ImageProcessor, ActionListener, ItemListener {

    public Map<UID, Filter> filtersMap = new LinkedHashMap<>();
    public Set<Filter> disabledFilters = new HashSet<>();
    public FiltersDialog dialog;

    public FiltersManager(FiltersDialog dialog) {
        this.dialog = dialog;
    }

    @SuppressWarnings("unchecked")
    private JPanel createFilterWithPanel(JsonObject meta) {

        FilterPanel fp = new FilterPanel();

        // listener to track sliders and checkbox of creating filter
        FilterGuiListener filterListener = new FilterGuiListener(this);

        String filterClassName = meta.getString("classname");

        String filterTitle = meta.getString("title");

        fp.setName(filterTitle);

        // creating model of the filter
        FilterStateModel filterState = new FilterStateModel();
        filterState.setFilterClassName(filterClassName);

        // loading jar with filter at runtime
        Class<?> clazz;

        // filter for adding to map states
        Filter filter = null;

        try {
            Main.debug("ClassName for loading " + filterState.getFilterClassName());
            clazz = FiltersDownloader.loader.loadClass(filterState
                    .getFilterClassName());
            filter = (Filter) clazz.getConstructor().newInstance();

        } catch (ReflectiveOperationException | IllegalArgumentException | SecurityException e) {
            e.printStackTrace();
        }

        if (filter != null) {

            UID filterId = new UID();
            fp.setFilterId(filterId);
            filterListener.setFilterId(filterId);
            filter.setId(filterId);
            filtersMap.put(filterId, filter);

            // all filters enabled in the beggining by default
        }

        fp.setBorder(BorderFactory.createTitledBorder(meta.getString("title")));

        JsonArray controls = meta.getJsonArray("controls");

        for (int i = 0; i < controls.size(); i++) {

            JsonObject temp = controls.getJsonObject(i);
            // Main.debug(temp.toString());

            JComponent component = fp.addGuiElement(temp);

            if (component != null) {

                if (component instanceof JSlider) {
                    ((JSlider) component).addChangeListener(filterListener);
                } else if (component instanceof JCheckBox) {
                    ((JCheckBox) component).addItemListener(filterListener);
                } else if (component instanceof JComboBox) {
                    ((JComboBox<String>) component).addActionListener(filterListener);
                } else if (component instanceof ColorPicker) {
                    ((ColorPicker) component).addPropertyChangeListener(filterListener);
                }

                // adding parameters to the filter instance
                filterState.addParams(temp);
            }
        }

        fp.setNeededHeight(fp.getNeededHeight() + 60);
        fp.setMaximumSize(new Dimension(300, fp.getNeededHeight()));
        fp.setPreferredSize(new Dimension(300, fp.getNeededHeight()));

        if (filter != null) {
            filter.changeFilterState(filterState.encodeJson());
        }
        Main.getLayerManager().getActiveLayer().setFilterStateChanged();

        fp.createBottomPanel(this);

        filterListener.setFilterState(filterState);

        Main.debug("The number of elems in the Filters map is equal \n"
                + filtersMap.size());

        return fp;
    }

    /**
     * The method notifies about changes in the filter's status.
     *
     * @param filterState - model that contains info about filter which was changed
     */
    @Override
    public void filterStateChanged(UID filterId, FilterStateModel filterState) {

        if (filtersMap.get(filterId) != null) {
            filtersMap.get(filterId).changeFilterState(filterState.encodeJson());
        }

        if (Main.getLayerManager().getActiveLayer() != null) {
            Main.getLayerManager().getActiveLayer().setFilterStateChanged();
        }

    }

    public JPanel createPanelByTitle(String title) {

        for (JsonObject json : FiltersDownloader.filtersMeta) {

            if (json.getString("title").equals(title)) {
                return createFilterWithPanel(json);
            }
        }

        return null;
    }

    @Override
    public BufferedImage process(BufferedImage image) {

        Iterator<Filter> it = filtersMap.values().iterator();

        // iterating through map of filters according to the order
        while (it.hasNext()) {

            Filter curFilter = it.next();

            if (!disabledFilters.contains(curFilter)) {
                // if next filter will return null
                // we should take an old example of the image
                BufferedImage oldImg = image;

                // applying filter to the current image
                image = curFilter.applyFilter(image);

                if (image == null) {
                    image = oldImg;
                }
            }
        }

        return image;
    }

    @Override
    public void actionPerformed(ActionEvent e) {

        FilterPanel filterPanel = (FilterPanel) ((JButton) e.getSource())
                .getParent().getParent();

        UID filterId = filterPanel.getFilterId();

        // removing filter from the filters chain
        filtersMap.remove(filterId);

        dialog.getShowedFiltersTitles().remove(filterPanel.getName());

        // add filterTitle to the 'choose list' on the top
        dialog.getListModel().addElement(filterPanel.getName());

        // removing panel from filterContainer
        filterPanel.removeAll();
        dialog.getFilterContainer().remove(filterPanel);

        if (dialog.getFilterContainer().getComponentCount() == 0) {

            dialog.deleteFilterContainer();

        } else {

            dialog.getFilterContainer().revalidate();
            dialog.getFilterContainer().repaint();

        }

        // if there were no elements in the list
        // but then it appeared
        // button should be enabled
        if (!dialog.getAddButton().isEnabled()) {
            dialog.getFilterChooser().setEnabled(true);
            dialog.getAddButton().setEnabled(true);
        }

        Main.getLayerManager().getActiveLayer().setFilterStateChanged();

    }

    @Override
    public void itemStateChanged(ItemEvent e) {

        JCheckBox enableFilter = (JCheckBox) e.getSource();
        FilterPanel filterPanel = (FilterPanel) enableFilter.getParent()
                .getParent();

        if (enableFilter.isSelected()) {

            UID filterId = filterPanel.getFilterId();
            disabledFilters.add(filtersMap.get(filterId));

            Main.getLayerManager().getActiveLayer().setFilterStateChanged();

        } else {

            UID filterId = filterPanel.getFilterId();
            disabledFilters.remove(filtersMap.get(filterId));

            Main.getLayerManager().getActiveLayer().setFilterStateChanged();

        }
    }
}