// Copyright 2017 JanusGraph Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package org.janusgraph.graphdb.types;

import com.google.common.base.Preconditions;
import org.janusgraph.core.*;
import org.janusgraph.core.schema.EdgeLabelMaker;
import org.janusgraph.core.Multiplicity;
import org.janusgraph.graphdb.database.IndexSerializer;
import org.janusgraph.graphdb.database.serialize.AttributeHandler;
import org.janusgraph.graphdb.internal.Order;
import org.janusgraph.graphdb.internal.JanusGraphSchemaCategory;
import org.janusgraph.graphdb.transaction.StandardJanusGraphTx;
import org.apache.tinkerpop.gremlin.structure.Direction;

import static org.janusgraph.graphdb.types.TypeDefinitionCategory.INVISIBLE;
import static org.janusgraph.graphdb.types.TypeDefinitionCategory.UNIDIRECTIONAL;

/**
 * @author Matthias Broecheler (me@matthiasb.com)
 */

public class StandardEdgeLabelMaker extends StandardRelationTypeMaker implements EdgeLabelMaker {

    private Direction unidirectionality;

    public StandardEdgeLabelMaker(final StandardJanusGraphTx tx,
                                  final String name, final IndexSerializer indexSerializer,
                                  final AttributeHandler attributeHandler) {
        super(tx, name, indexSerializer, attributeHandler);
        unidirectionality = Direction.BOTH;
    }

    @Override
    JanusGraphSchemaCategory getSchemaCategory() {
        return JanusGraphSchemaCategory.EDGELABEL;
    }

    @Override
    public StandardEdgeLabelMaker directed() {
        unidirectionality = Direction.BOTH;
        return this;
    }

    @Override
    public StandardEdgeLabelMaker unidirected() {
        return unidirected(Direction.OUT);
    }

    public StandardEdgeLabelMaker unidirected(Direction dir) {
        Preconditions.checkNotNull(dir);
        unidirectionality = dir;
        return this;
    }

    @Override
    public StandardEdgeLabelMaker multiplicity(Multiplicity multiplicity) {
        super.multiplicity(multiplicity);
        return this;
    }

    @Override
    public StandardEdgeLabelMaker signature(PropertyKey... types) {
        super.signature(types);
        return this;
    }

    @Override
    public StandardEdgeLabelMaker sortKey(PropertyKey... types) {
        super.sortKey(types);
        return this;
    }

    @Override
    public StandardEdgeLabelMaker sortOrder(Order order) {
        super.sortOrder(order);
        return this;
    }

    @Override
    public StandardEdgeLabelMaker invisible() {
        super.invisible();
        return this;
    }

    @Override
    public EdgeLabel make() {
        TypeDefinitionMap definition = makeDefinition();
        Preconditions.checkArgument(unidirectionality==Direction.BOTH || !getMultiplicity().isUnique(unidirectionality.opposite()),
                "Unidirectional labels cannot have restricted multiplicity at the other end");
        Preconditions.checkArgument(unidirectionality==Direction.BOTH || !hasSortKey() ||
                !getMultiplicity().isUnique(unidirectionality),
                "Unidirectional labels with restricted multiplicity cannot have a sort key");
        Preconditions.checkArgument(unidirectionality!=Direction.IN || definition.getValue(INVISIBLE,Boolean.class));


        definition.setValue(UNIDIRECTIONAL, unidirectionality);
        return tx.makeEdgeLabel(getName(), definition);
    }

}