/*******************************************************************************
 * Copyright (c) 2012 Association for Decentralized Information Management in
 * Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.modeling.ui.sharedontology.wizard;

import java.io.File;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Deque;
import java.util.HashMap;
import java.util.Map;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.SubMonitor;
import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.jface.operation.IRunnableWithProgress;
import org.eclipse.jface.preference.IPersistentPreferenceStore;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.wizard.Wizard;
import org.eclipse.jface.wizard.WizardPage;
import org.eclipse.swt.SWT;
import org.eclipse.ui.IImportWizard;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.preferences.ScopedPreferenceStore;
import org.simantics.databoard.binding.Binding;
import org.simantics.databoard.binding.mutable.Variant;
import org.simantics.databoard.container.DataContainer;
import org.simantics.databoard.container.DataContainers;
import org.simantics.databoard.container.FormatHandler;
import org.simantics.databoard.util.URIStringUtils;
import org.simantics.db.Resource;
import org.simantics.db.Session;
import org.simantics.db.layer0.migration.MigratedImportResult;
import org.simantics.db.layer0.migration.MigrationUtils;
import org.simantics.db.layer0.util.DraftStatusBean;
import org.simantics.db.management.ISessionContext;
import org.simantics.graph.db.MissingDependencyException;
import org.simantics.graph.representation.TransferableGraph1;
import org.simantics.modeling.ui.Activator;
import org.simantics.modeling.ui.utils.NoProjectPage;
import org.simantics.project.IProject;
import org.simantics.project.ProjectKeys;
import org.simantics.ui.SimanticsUI;
import org.simantics.ui.utils.ResourceAdaptionUtils;
import org.simantics.utils.strings.EString;
import org.simantics.utils.ui.ErrorLogger;
import org.simantics.utils.ui.ExceptionUtils;
import org.simantics.utils.ui.dialogs.InfoDialog;

/**
 * @author Tuukka Lehtonen
 */
public class SharedOntologyImportWizard extends Wizard implements IImportWizard {

    private static final int MAX_RECENT_IMPORT_PATHS = 10;

    ImportPlan        importModel;

    private boolean readPreferences(IStructuredSelection selection) {
        IPreferenceStore store = new ScopedPreferenceStore(InstanceScope.INSTANCE, Activator.PLUGIN_ID);

        String recentPathsPref = store.getString(Preferences.RECENT_SHARED_LIBRARY_IMPORT_LOCATIONS);
        Deque<String> recentImportPaths = Preferences.decodePaths(recentPathsPref);

        ISessionContext ctx = SimanticsUI.getSessionContext();
        if (ctx == null)
            return false;
        IProject project = ctx.getHint(ProjectKeys.KEY_PROJECT);
        if (project == null)
            return false;

        importModel = new ImportPlan(ctx, recentImportPaths);
        importModel.project = project;
        importModel.selection = selection.getFirstElement();

        return true;
    }

    private void writePreferences() throws IOException {
        IPersistentPreferenceStore store = new ScopedPreferenceStore(InstanceScope.INSTANCE, Activator.PLUGIN_ID);

        store.putValue(Preferences.RECENT_SHARED_LIBRARY_IMPORT_LOCATIONS, Preferences.encodePaths(importModel.recentLocations));

        if (store.needsSaving())
            store.save();
    }

    public SharedOntologyImportWizard() {
        setWindowTitle("Import Shared Library");
        setNeedsProgressMonitor(true);
    }

    @Override
    public void init(IWorkbench workbench, IStructuredSelection selection) {
        readPreferences(selection);
    }

    @Override
    public void addPages() {
        super.addPages();
        if (importModel != null) {
            addPage(new SharedOntologyImportPage(importModel));
        } else {
            addPage(new NoProjectPage("Import Shared Library"));
        }
    }

    @Override
    public boolean performFinish() {
        try {
            importModel.recentLocations.addFirst(importModel.importLocation.getAbsolutePath());
            Preferences.removeDuplicates(importModel.recentLocations);
            if (importModel.recentLocations.size() > MAX_RECENT_IMPORT_PATHS)
                importModel.recentLocations.pollLast();

            writePreferences();
        } catch (IOException e) {
            ErrorLogger.defaultLogError("Failed to write preferences", e);
        }

        try {
            MigratedImportResult[] result = { null };
            getContainer().run(true, true, new IRunnableWithProgress() {
                @Override
                public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException {
                    try {
                        Resource target = ResourceAdaptionUtils.toSingleResource(importModel.selection);
                        importModel.sessionContext.getSession().markUndoPoint();
                        result[0] = doImport(monitor, importModel.importLocation, importModel.sessionContext.getSession(), target);
                    } catch (Exception e) {
                        throw new InvocationTargetException(e);
                    } finally {
                        monitor.done();
                    }
                }
            });

            if (result[0].hasMissingExternals()) {
                InfoDialog.open(getShell(), "Missing Externals Created",
                        "The system was unable to find some of the external entities referenced by the imported material. Place-holders have been created for the missing entities.\nThe missing entities are:\n"
                                + URIStringUtils.unescape(EString.implode(result[0].tgResult.missingExternals)),
                        SWT.SHEET);
            }
        } catch (InvocationTargetException e) {
            Throwable cause = e.getCause();
            WizardPage cp = (WizardPage) getContainer().getCurrentPage();
            if (cause instanceof MissingDependencyException) {
                cp.setErrorMessage("Failed to import shared library due to missing dependencies.\n" + cause.getMessage());
                ErrorLogger.defaultLogError("Shared Library " + importModel.importLocation + " import failed due to missing database dependencies. See exception for details.", cause);
                ExceptionUtils.showError("Failed to import shared library due to missing dependencies.\n\n" + cause.getMessage(), null);
            } else {
                cp.setErrorMessage("Unexpected problem importing shared library.\nMessage: " + cause.getMessage());
                ErrorLogger.defaultLogError("Shared Library " + importModel.importLocation + " import failed unexpectedly. See exception for details.", cause);
                ExceptionUtils.showError("Unexpected problem importing shared library.\n\n" + cause.getMessage(), cause);
            }
            return false;
        } catch (InterruptedException e) {
            WizardPage cp = (WizardPage) getContainer().getCurrentPage();
            cp.setErrorMessage("Import interrupted.\nMessage: " + e.getMessage());
            ErrorLogger.defaultLogError("Shared Library " + importModel.importLocation + " import interrupted.", e);
            ExceptionUtils.showError("Shared library import was interrupted.", e);
            return false;
        }

        return true;
    }

    public static MigratedImportResult doImport(IProgressMonitor monitor, File modelFile, Session session, Resource target)
            throws Exception
    {
        SubMonitor mon = SubMonitor.convert(monitor);
        mon.beginTask("Loading shared library from disk", 1000);

        FormatHandler<MigratedImportResult> handler1 = new FormatHandler<MigratedImportResult>() {
            @Override
            public Binding getBinding() {
                return TransferableGraph1.BINDING;
            }

            @Override
            public MigratedImportResult process(DataContainer container) throws Exception {
                mon.worked(100);
                mon.setTaskName("Importing shared library into database");
                Variant draftStatus = container.metadata.get(DraftStatusBean.EXTENSION_KEY);
                TransferableGraph1 tg = (TransferableGraph1) container.content.getValue();
                return MigrationUtils.importSharedOntology(mon.newChild(850, SubMonitor.SUPPRESS_NONE), session, tg, draftStatus == null);
            }
        };

        Map<String, FormatHandler<MigratedImportResult>> handlers = new HashMap<>();
        handlers.put(Constants.SHARED_LIBRARY_FORMAT_V1, handler1);

        MigratedImportResult result = DataContainers.readFile(modelFile, handlers);

        mon.setTaskName("Postprocessing");
        mon.subTask("");
        mon.newChild(50).done();

        return result;
    }

}