/*******************************************************************************
 * Copyright (c) 2007 VTT Technical Research Centre of Finland and others.
 * 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.proconf.g3d.shapeeditor.common;

import java.util.Collection;

import org.simantics.db.Builtins;
import org.simantics.db.Resource;
import org.simantics.layer0.utils.Statement;
import org.simantics.layer0.utils.IEntity;
import org.simantics.layer0.utils.viewpoints.AcceptDecision;
import org.simantics.layer0.utils.viewpoints.AcceptRule;
import org.simantics.layer0.utils.viewpoints.PlainStateFactory;
import org.simantics.layer0.utils.viewpoints.ResourceViewpoint;
import org.simantics.layer0.utils.viewpoints.State;
import org.simantics.layer0.utils.viewpoints.StateFactory;
import org.simantics.layer0.utils.viewpoints.TraversalDecision;
import org.simantics.layer0.utils.viewpoints.TraversalRule;
import org.simantics.layer0.utils.viewpoints.rules.AcceptAllResourceAcceptRule;
import org.simantics.proconf.g3d.shapeeditor.ShapeEditorResources;


public class ViewpointGenerator {
	
	public static ResourceViewpoint createStuctureViewpoint() {
		StateFactory f = new PlainStateFactory();
		final State rootState = f.newState();
		final State projectState = f.newState();
		final State libraryState = f.newState();

		return new ResourceViewpoint(new TraversalRule() {
			@Override
			public TraversalDecision makeTraversalDecision(State state,
					Statement statement) {
				Builtins b = statement.getGraph().getBuiltins();
				if (state.equals(rootState)) {
					if (!statement.getPredicate().equals(b.ConsistsOf))
						return TraversalDecision.stopTraversal;
					//if (!statement.getObject().isInstanceOf(b.Project))
					//    return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(projectState);
				} else if (state.equals(projectState)) {
					if (!statement.getPredicate().equals(b.ConsistsOf))
						return TraversalDecision.stopTraversal;
					//if (!statement.getObject().isInstanceOf(b.Library))
					//    return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(libraryState);
				} else if (state.equals(libraryState)) {
					if (!statement.getPredicate().equals(b.ConsistsOf)
							&& !statement.getPredicate().isSubrelationOf(
									ShapeEditorResources.g3dResource.HasChild))
						return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(libraryState);
				}
				return TraversalDecision.stopTraversal;
			}

			@Override
			public boolean areAllStatesRelevant() {
				return true;
			}

			@Override
			public Collection<State> relevantStates() {
				return null;
			}
		}, new AcceptAllResourceAcceptRule(), rootState);
	}
	
	public static ResourceViewpoint createObjectStructureViewpoint() {
		StateFactory f = new PlainStateFactory();
		final State rootState = f.newState();

		return new ResourceViewpoint(new TraversalRule() {
			@Override
			public TraversalDecision makeTraversalDecision(State state,
					Statement statement) {
				if (state.equals(rootState)) {
					if (!statement.getPredicate().isSubrelationOf(
							ShapeEditorResources.g3dResource.HasChild))
						return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(rootState);
				}
				return TraversalDecision.stopTraversal;
			}

			@Override
			public boolean areAllStatesRelevant() {
				return true;
			}

			@Override
			public Collection<State> relevantStates() {
				return null;
			}
		}, new AcceptAllResourceAcceptRule(), rootState);
	}
	
	public static ResourceViewpoint createObjectSizingParameterViewpoint(Resource modelToParameterRelation) {
		StateFactory f = new PlainStateFactory();
		final State rootState = f.newState();
		final State endState = f.newState();
		final Resource relation = modelToParameterRelation;

		return new ResourceViewpoint(new TraversalRule() {
			@Override
			public TraversalDecision makeTraversalDecision(State state,
					Statement statement) {
				if (state.equals(rootState)) {
					if (!statement.getPredicate().isSubrelationOf(relation))
						return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(endState);
				}
				return TraversalDecision.stopTraversal;
			}

			@Override
			public boolean areAllStatesRelevant() {
				return true;
			}

			@Override
			public Collection<State> relevantStates() {
				return null;
			}
		}, new AcceptAllResourceAcceptRule(), rootState);
	}
	
	public static ResourceViewpoint createViewpoint() {
		StateFactory f = new PlainStateFactory();
		final State rootState = f.newState();
		final State projectState = f.newState();
		final State libraryState = f.newState();
		
		return new ResourceViewpoint(new TraversalRule() {
			@Override
			public TraversalDecision makeTraversalDecision(State state, Statement statement) {
				Builtins b = statement.getGraph().getBuiltins();
				if (state.equals(rootState)) {
					if (statement.getObject().isInstanceOf(b.Ontology))
						return TraversalDecision.stopTraversal;
					if(!statement.getPredicate().equals(b.ConsistsOf))
						return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(projectState);
				} else if (state.equals(projectState)) {
					if(!statement.getPredicate().equals(b.ConsistsOf))
						return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(libraryState);
				} else if (state.equals(libraryState)) {
					if(!statement.getPredicate().equals(b.ConsistsOf))
						return TraversalDecision.stopTraversal;
					return TraversalDecision.continueTraversal(libraryState);
				}
				return TraversalDecision.stopTraversal;
			}
			
			@Override
			public boolean areAllStatesRelevant() {
				return true;
			}
			
			@Override
			public Collection<State> relevantStates() {
				return null;
			}
		}, new AcceptRule<IEntity>() {
		@Override
			public AcceptDecision makeAcceptDecision(State state, IEntity obj) {
				Builtins b = obj.getGraph().getBuiltins();
				//NOSEResource nr = NOSEResource.getInstance(obj.getGraph());
				if(obj.isInstanceOf(b.Project)) return AcceptDecision.REJECT;
				else if (obj.isInstanceOf(b.Ontology)) return AcceptDecision.REJECT;
				else return AcceptDecision.ACCEPT;
			}
		
			@Override
			public boolean areAllStatesRelevant() {
				return true;
			}
			
			@Override
			public Collection<State> relevantStates() {
				return null;
			}
		}, rootState);
	}

}