/*******************************************************************************
 * Copyright (c) 2011, 2016 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
 *     Semantum Oy - refactoring
 *******************************************************************************/
package org.simantics.modeling.ui.actions;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExecutableExtension;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.ActionContributionItem;
import org.eclipse.jface.action.IContributionItem;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.osgi.util.NLS;
import org.simantics.browsing.ui.NodeContext;
import org.simantics.browsing.ui.common.NodeContextBuilder;
import org.simantics.browsing.ui.model.InvalidContribution;
import org.simantics.browsing.ui.model.actions.ActionBrowseContext;
import org.simantics.browsing.ui.model.actions.IActionCategory;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.issues.common.IssueUtils;
import org.simantics.modeling.ui.Activator;
import org.simantics.project.ontology.ProjectResource;
import org.simantics.ui.contribution.DynamicMenuContribution;
import org.simantics.ui.selection.WorkbenchSelectionUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ModeledActions extends DynamicMenuContribution implements IExecutableExtension {
    private static final Logger LOGGER = LoggerFactory.getLogger(IssueUtils.class);

    public static final Set<String> defaultBrowseContexts = Collections.singleton(ProjectResource.URIs.ProjectActionContext);

    protected Set<String> browseContexts = defaultBrowseContexts;

    public static final Comparator<Action> ACTION_COMPARATOR = new Comparator<Action>() {
        @Override
        public int compare(Action o1, Action o2) {
            String t1 = o1.getText();
            String t2 = o2.getText();
            if(t1 == null) {
                if(t2 == null)
                    return 0;
                else
                    return -1;
            }           
            else {
                if(t2 == null)
                    return 1;
                else
                    return t1.compareTo(t2);
            }
        }
    };

    @Override
    public void setInitializationData(IConfigurationElement config, String propertyName, Object data) throws CoreException {
        if(data instanceof String) {
            String str = (String)data;
            String[] parms = str.split(";"); //$NON-NLS-1$
            for(String parm : parms) {
                String[] keyValue = parm.split("="); //$NON-NLS-1$
                if(keyValue.length == 2) {
                    String key = keyValue[0].trim();
                    if("context".equals(key)) { //$NON-NLS-1$
                        browseContexts = Collections.singleton(keyValue[1]);
                    }
                }
            }
        }
    }

    protected Collection<String> getBrowseContexts() {
        return browseContexts;
    }

    protected Collection<Resource> getBrowseContextResources(ReadGraph graph) throws DatabaseException {
        Collection<String> names = getBrowseContexts(); 
        ArrayList<Resource> result = new ArrayList<>(names.size());
        for(String name : names)
            result.add(graph.getResource(name));
        return result;
    }

    protected List<NodeContext> getContexts(Object[] selection) {
        if (selection.length == 0)
            return Collections.emptyList();

        ArrayList<NodeContext> result = new ArrayList<>(selection.length);

        for (Object o : selection) {
            if ((o instanceof IAdaptable)) {
	            NodeContext nodeContext = ((IAdaptable) o).getAdapter(NodeContext.class);
	            if (nodeContext != null) {
	                result.add(nodeContext);
	                continue;
	            }
            }
            try {
            	Resource res = WorkbenchSelectionUtils.getPossibleResource(o);
            	if(res != null) {
            		result.add(NodeContextBuilder.buildWithInput(res));
            	}
            } catch (DatabaseException e) {
            	LOGGER.error("Failed to get node contexts for selection.", e); //$NON-NLS-1$
            }
        }

        return result;
    }

    protected List<NodeContext> getContexts(ReadGraph graph, Object[] selection) throws DatabaseException {
        return getContexts(selection);
    }

    protected static IContributionItem[] toContributionItems(Map<IActionCategory, List<Action>> map) {
        if (map.isEmpty())
            return NONE;

        IActionCategory[] categories = map.keySet().toArray(new IActionCategory[map.size()]);
        Arrays.sort(categories, IActionCategory.ACTION_CATEGORY_COMPARATOR);

        ArrayList<IContributionItem> items = new ArrayList<IContributionItem>();
        boolean first = true;
        for (IActionCategory category : categories) {
            List<Action> actions = map.get(category);
            Collections.sort(actions, ACTION_COMPARATOR);

            if (category != null && category.isSubmenu()) {
                MenuManager manager = new MenuManager(category.getLabel());
                for (Action action : actions)
                    manager.add(new ActionContributionItem(action));
                items.add(manager);
            }
            else {
                if (first)
                    first = false;
                else
                    items.add(new Separator(category == null ? "" : category.getLabel())); //$NON-NLS-1$
                for (Action action : actions)
                    items.add(new ActionContributionItem(action));
            }
        }
        return items.toArray(new IContributionItem[items.size()]);
    }

    @Override
    protected Object[] getSelectedObjects() {
        Object[] sel = super.getSelectedObjects();
        List<NodeContext> contexts = getContexts(sel);
        return contexts.toArray(NodeContext.NONE);
    }

    @Override
    protected IContributionItem[] getContributionItems(ReadGraph graph, Object[] selection) throws DatabaseException {
        List<NodeContext> contexts = Arrays.asList((NodeContext[]) selection);
        if (contexts.isEmpty())
            return NONE;

        try {
            NodeContext nodeContext = contexts.get(0);

            ActionBrowseContext defaultContext = ActionBrowseContext.create(graph, getBrowseContextResources(graph));
            ActionBrowseContext browseContext = ActionBrowseContext.get(graph, nodeContext, defaultContext);

            Map<IActionCategory, List<Action>> result = browseContext.getActions(graph, nodeContext, contexts);
            Map<IActionCategory, List<Action>> current = result;

            for (int i = 1; i < contexts.size(); i++) {

                browseContext = ActionBrowseContext.get(graph, nodeContext, defaultContext);

                Map<IActionCategory, List<Action>> m = browseContext.getActions(graph, contexts.get(i), contexts);

                result = new HashMap<>();

                for (Map.Entry<IActionCategory, List<Action>> entry : m.entrySet()) {
                    List<Action> exist = current.get(entry.getKey());
                    if (exist == null)
                        continue;

                    ArrayList<Action> l = new ArrayList<Action>();
                    for (Action e : exist) {
                        String id = e.getId();
                        boolean found = false;
                        for (Action a : entry.getValue()) {
                            if (id.equals(a.getId())) {
                                found = true;
                                break;
                            }
                        }
                        if (found)
                            l.add(e);
                    }
                    if (!l.isEmpty())
                        result.put(entry.getKey(), l);
                }

                current = result;

            }

            return toContributionItems(result);

        } catch (InvalidContribution e) {
            Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID,
                    NLS.bind(Messages.ModeledActions_ActivatorInvalidContributionsEncounteredIn,
                            getClass().getSimpleName()),
                    e));
        }
        return NONE;
    }

}