/*
 * Copyright 2017 the original author or 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.gradle.api.internal.artifacts.ivyservice.resolveengine.graph.builder;

import com.google.common.collect.Maps;
import org.gradle.api.artifacts.ModuleIdentifier;

import java.util.Map;

/**
 * Maintains state about the optionality of all modules seen during graph traversal.
 */
public class OptionalDependenciesState {
    private static final PendingOptionalDependencies NOT_OPTIONAL = PendingOptionalDependencies.notOptional();

    private final Map<ModuleIdentifier, PendingOptionalDependencies> optionalDependencies = Maps.newHashMap();

    public PendingOptionalDependencies getPendingOptionalDependencies(ModuleIdentifier module) {
        PendingOptionalDependencies pendingOptionalDependencies = optionalDependencies.get(module);
        if (pendingOptionalDependencies == null) {
            pendingOptionalDependencies = PendingOptionalDependencies.pending();
            optionalDependencies.put(module, pendingOptionalDependencies);
        }
        return pendingOptionalDependencies;
    }

    public void notOptional(ModuleIdentifier module) {
        optionalDependencies.put(module, NOT_OPTIONAL);
    }
}
