// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.actions;

import static org.openstreetmap.josm.gui.help.HelpUtil.ht;
import static org.openstreetmap.josm.tools.I18n.tr;

import java.awt.Dimension;
import java.awt.GraphicsEnvironment;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.io.IOException;
import java.net.MalformedURLException;
import java.util.HashSet;
import java.util.Set;

import javax.swing.JComboBox;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.data.imagery.ImageryInfo;
import org.openstreetmap.josm.data.imagery.ImageryInfo.ImageryType;
import org.openstreetmap.josm.gui.ExtendedDialog;
import org.openstreetmap.josm.gui.layer.AlignImageryPanel;
import org.openstreetmap.josm.gui.layer.ImageryLayer;
import org.openstreetmap.josm.gui.preferences.imagery.WMSLayerTree;
import org.openstreetmap.josm.gui.util.GuiHelper;
import org.openstreetmap.josm.io.imagery.WMSImagery;
import org.openstreetmap.josm.io.imagery.WMSImagery.LayerDetails;
import org.openstreetmap.josm.io.imagery.WMSImagery.WMSGetCapabilitiesException;
import org.openstreetmap.josm.tools.GBC;
import org.openstreetmap.josm.tools.ImageProvider;
import org.openstreetmap.josm.tools.ImageProvider.ImageResourceCallback;
import org.openstreetmap.josm.tools.ImageResource;

/**
 * Action displayed in imagery menu to add a new imagery layer.
 * @since 3715
 */
public class AddImageryLayerAction extends JosmAction implements AdaptableAction {
    private final transient ImageryInfo info;

    /**
     * Constructs a new {@code AddImageryLayerAction} for the given {@code ImageryInfo}.
     * If an http:// icon is specified, it is fetched asynchronously.
     * @param info The imagery info
     */
    public AddImageryLayerAction(ImageryInfo info) {
        super(info.getMenuName(), /* ICON */"imagery_menu", tr("Add imagery layer {0}", info.getName()), null, false, false);
        putValue("toolbar", "imagery_" + info.getToolbarName());
        putValue("help", ht("/Preferences/Imagery"));
        this.info = info;
        installAdapters();

        // change toolbar icon from if specified
        String icon = info.getIcon();
        if (icon != null) {
            new ImageProvider(icon).setOptional(true).getInBackground(new ImageResourceCallback() {
                        @Override
                        public void finished(final ImageResource result) {
                            if (result != null) {
                                GuiHelper.runInEDT(new Runnable() {
                                    @Override
                                    public void run() {
                                        result.attachImageIcon(AddImageryLayerAction.this);
                                    }
                                });
                            }
                        }
                    });
        }
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (!isEnabled()) return;
        try {
            final ImageryInfo infoToAdd = ImageryType.WMS_ENDPOINT.equals(info.getImageryType())
                    ? getWMSLayerInfo() : info;
            if (infoToAdd != null) {
                Main.getLayerManager().addLayer(ImageryLayer.create(infoToAdd));
                AlignImageryPanel.addNagPanelIfNeeded(infoToAdd);
            }
        } catch (IllegalArgumentException ex) {
            if (ex.getMessage() == null || ex.getMessage().isEmpty()) {
                throw ex;
            } else {
                JOptionPane.showMessageDialog(Main.parent,
                        ex.getMessage(), tr("Error"),
                        JOptionPane.ERROR_MESSAGE);
            }
        }
    }

    protected ImageryInfo getWMSLayerInfo() {
        try {
            assert ImageryType.WMS_ENDPOINT.equals(info.getImageryType());
            final WMSImagery wms = new WMSImagery();
            wms.attemptGetCapabilities(info.getUrl());

            final WMSLayerTree tree = new WMSLayerTree();
            tree.updateTree(wms);
            final JComboBox<String> formats = new JComboBox<>(wms.getFormats().toArray(new String[0]));
            formats.setSelectedItem(wms.getPreferredFormats());
            formats.setToolTipText(tr("Select image format for WMS layer"));

            if (!GraphicsEnvironment.isHeadless()) {
                if (1 != new ExtendedDialog(Main.parent, tr("Select WMS layers"), new String[]{tr("Add layers"), tr("Cancel")}) { {
                    final JScrollPane scrollPane = new JScrollPane(tree.getLayerTree());
                    scrollPane.setPreferredSize(new Dimension(400, 400));
                    final JPanel panel = new JPanel(new GridBagLayout());
                    panel.add(scrollPane, GBC.eol().fill());
                    panel.add(formats, GBC.eol().fill(GBC.HORIZONTAL));
                    setContent(panel);
                } }.showDialog().getValue()) {
                    return null;
                }
            }

            final String url = wms.buildGetMapUrl(
                    tree.getSelectedLayers(), (String) formats.getSelectedItem());
            Set<String> supportedCrs = new HashSet<>();
            boolean first = true;
            StringBuilder layersString = new StringBuilder();
            for (LayerDetails layer: tree.getSelectedLayers()) {
                if (first) {
                    supportedCrs.addAll(layer.getProjections());
                    first = false;
                }
                layersString.append(layer.name);
                layersString.append(", ");
                supportedCrs.retainAll(layer.getProjections());
            }

            ImageryInfo ret = new ImageryInfo(info.getName(), url, "wms", info.getEulaAcceptanceRequired(), info.getCookies());
            if (layersString.length() > 2) {
                ret.setName(ret.getName() + ' ' + layersString.substring(0, layersString.length() - 2));
            }
            ret.setServerProjections(supportedCrs);
            return ret;
        } catch (MalformedURLException ex) {
            if (!GraphicsEnvironment.isHeadless()) {
                JOptionPane.showMessageDialog(Main.parent, tr("Invalid service URL."),
                        tr("WMS Error"), JOptionPane.ERROR_MESSAGE);
            }
            Main.error(ex, false);
        } catch (IOException ex) {
            if (!GraphicsEnvironment.isHeadless()) {
                JOptionPane.showMessageDialog(Main.parent, tr("Could not retrieve WMS layer list."),
                        tr("WMS Error"), JOptionPane.ERROR_MESSAGE);
            }
            Main.error(ex, false);
        } catch (WMSGetCapabilitiesException ex) {
            if (!GraphicsEnvironment.isHeadless()) {
                JOptionPane.showMessageDialog(Main.parent, tr("Could not parse WMS layer list."),
                        tr("WMS Error"), JOptionPane.ERROR_MESSAGE);
            }
            Main.error(ex, "Could not parse WMS layer list. Incoming data:\n"+ex.getIncomingData());
        }
        return null;
    }

    @Override
    protected void updateEnabledState() {
        ImageryType type = info.getImageryType();
        // never enable blacklisted entries. Do not add same imagery layer twice (fix #2519)
        if (info.isBlacklisted()) {
            setEnabled(false);
        } else if (type == ImageryType.TMS || type == ImageryType.BING || type == ImageryType.SCANEX) {
            setEnabled(true);
        } else {
            setEnabled(!Main.getLayerManager().getLayers().isEmpty());
        }
    }
}