// License: GPL. Copyright 2007 by Immanuel Scholz and others
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.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.util.LinkedList;
import java.util.logging.Logger;

import javax.swing.JOptionPane;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.actions.upload.ApiPreconditionCheckerHook;
import org.openstreetmap.josm.actions.upload.RelationUploadOrderHook;
import org.openstreetmap.josm.actions.upload.UploadHook;
import org.openstreetmap.josm.data.APIDataSet;
import org.openstreetmap.josm.data.conflict.ConflictCollection;
import org.openstreetmap.josm.gui.HelpAwareOptionPane;
import org.openstreetmap.josm.gui.help.HelpUtil;
import org.openstreetmap.josm.gui.io.UploadDialog;
import org.openstreetmap.josm.gui.io.UploadPrimitivesTask;
import org.openstreetmap.josm.gui.layer.OsmDataLayer;
import org.openstreetmap.josm.tools.Shortcut;

/**
 * Action that opens a connection to the osm server and uploads all changes.
 *
 * An dialog is displayed asking the user to specify a rectangle to grab.
 * The url and account settings from the preferences are used.
 *
 * If the upload fails this action offers various options to resolve conflicts.
 *
 * @author imi
 */
public class UploadAction extends JosmAction{
    @SuppressWarnings("unused")
    static private Logger logger = Logger.getLogger(UploadAction.class.getName());
    /**
     * The list of upload hooks. These hooks will be called one after the other
     * when the user wants to upload data. Plugins can insert their own hooks here
     * if they want to be able to veto an upload.
     *
     * Be default, the standard upload dialog is the only element in the list.
     * Plugins should normally insert their code before that, so that the upload
     * dialog is the last thing shown before upload really starts; on occasion
     * however, a plugin might also want to insert something after that.
     */
    private static final LinkedList<UploadHook> uploadHooks = new LinkedList<UploadHook>();
    static {
        /**
         * Checks server capabilities before upload.
         */
        uploadHooks.add(new ApiPreconditionCheckerHook());

        /**
         * Adjusts the upload order of new relations
         */
        uploadHooks.add(new RelationUploadOrderHook());
    }

    /**
     * Registers an upload hook. Adds the hook at the first position of the upload hooks.
     *
     * @param hook the upload hook. Ignored if null.
     */
    public static void registerUploadHook(UploadHook hook) {
        if(hook == null) return;
        if (!uploadHooks.contains(hook)) {
            uploadHooks.add(0,hook);
        }
    }

    /**
     * Unregisters an upload hook. Removes the hook from the list of upload hooks.
     *
     * @param hook the upload hook. Ignored if null.
     */
    public static void unregisterUploadHook(UploadHook hook) {
        if(hook == null) return;
        if (uploadHooks.contains(hook)) {
            uploadHooks.remove(hook);
        }
    }

    public UploadAction() {
        super(tr("Upload data"), "upload", tr("Upload all changes in the active data layer to the OSM server"),
                Shortcut.registerShortcut("file:upload", tr("File: {0}", tr("Upload data")), KeyEvent.VK_U, Shortcut.GROUPS_ALT1+Shortcut.GROUP_HOTKEY), true);
        putValue("help", ht("/Action/Upload"));
    }

    /**
     * Refreshes the enabled state
     *
     */
    @Override
    protected void updateEnabledState() {
        setEnabled(getEditLayer() != null);
    }

    public boolean checkPreUploadConditions(OsmDataLayer layer) {
        return checkPreUploadConditions(layer, new APIDataSet(layer.data));
    }

    protected void alertUnresolvedConflicts(OsmDataLayer layer) {
        HelpAwareOptionPane.showOptionDialog(
                Main.parent,
                tr("<html>The data to be uploaded participates in unresolved conflicts of layer ''{0}''.<br>"
                        + "You have to resolve them first.</html>", layer.getName()
                ),
                tr("Warning"),
                JOptionPane.WARNING_MESSAGE,
                HelpUtil.ht("/Action/Upload#PrimitivesParticipateInConflicts")
        );
    }

    /**
     * Check whether the preconditions are met to upload data in <code>apiData</code>.
     * Makes sure primitives in <code>apiData</code> don't participate in conflicts and
     * runs the installed {@see UploadHook}s.
     * 
     * @param layer the source layer of the data to be uploaded
     * @param apiData the data to be uploaded
     * @return true, if the preconditions are met; false, otherwise
     */
    public boolean checkPreUploadConditions(OsmDataLayer layer, APIDataSet apiData) {
        ConflictCollection conflicts = layer.getConflicts();
        if (apiData.participatesInConflict(conflicts)) {
            alertUnresolvedConflicts(layer);
            return false;
        }
        // Call all upload hooks in sequence.
        // FIXME: this should become an asynchronous task
        //
        for(UploadHook hook : uploadHooks)
            if(!hook.checkUpload(apiData))
                return false;

        return true;
    }

    /**
     * Uploads data to the OSM API.
     * 
     * @param layer the source layer for the data to upload
     * @param apiData the primitives to be added, updated, or deleted
     */
    public void uploadData(OsmDataLayer layer, APIDataSet apiData) {
        if (apiData.isEmpty()) {
            JOptionPane.showMessageDialog(
                    Main.parent,
                    tr("No changes to upload."),
                    tr("Warning"),
                    JOptionPane.INFORMATION_MESSAGE
            );
            return;
        }
        if (!checkPreUploadConditions(layer, apiData))
            return;

        final UploadDialog dialog = UploadDialog.getUploadDialog();
        dialog.setUploadedPrimitives(apiData);
        dialog.setVisible(true);
        if (dialog.isCanceled())
            return;
        dialog.rememberUserInput();

        Main.worker.execute(
                new UploadPrimitivesTask(
                        UploadDialog.getUploadDialog().getUploadStrategySpecification(),
                        layer,
                        apiData,
                        UploadDialog.getUploadDialog().getChangeset()
                )
        );
    }

    public void actionPerformed(ActionEvent e) {
        if (!isEnabled())
            return;
        if (Main.map == null) {
            JOptionPane.showMessageDialog(
                    Main.parent,
                    tr("Nothing to upload. Get some data first."),
                    tr("Warning"),
                    JOptionPane.WARNING_MESSAGE
            );
            return;
        }
        APIDataSet apiData = new APIDataSet(Main.main.getCurrentDataSet());
        uploadData(Main.map.mapView.getEditLayer(), apiData);
    }
}