/**
 * Copyright (C) 2006 Google Inc.
 * <p>
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.apache.struts2.inject;

import java.util.HashMap;
import java.util.Map;

/**
 * Internal context. Used to coordinate injections and support circular
 * dependencies.
 *
 * @author crazybob@google.com (Bob Lee)
 */
class InternalContext {

    final ContainerImpl container;
    final Map<Object, ConstructionContext<?>> constructionContexts = new HashMap<>();
    Scope.Strategy scopeStrategy;
    ExternalContext<?> externalContext;

    InternalContext(ContainerImpl container) {
        this.container = container;
    }

    public Container getContainer() {
        return container;
    }

    ContainerImpl getContainerImpl() {
        return container;
    }

    Scope.Strategy getScopeStrategy() {
        if (scopeStrategy == null) {
            scopeStrategy = (Scope.Strategy) container.localScopeStrategy.get();

            if (scopeStrategy == null) {
                throw new IllegalStateException("Scope strategy not set. Please call Container.setScopeStrategy().");
            }
        }

        return scopeStrategy;
    }

    @SuppressWarnings("unchecked")
    <T> ConstructionContext<T> getConstructionContext(Object key) {
        ConstructionContext<T> constructionContext = (ConstructionContext<T>) constructionContexts.get(key);
        if (constructionContext == null) {
            constructionContext = new ConstructionContext<>();
            constructionContexts.put(key, constructionContext);
        }
        return constructionContext;
    }

    @SuppressWarnings("unchecked")
    <T> ExternalContext<T> getExternalContext() {
        return (ExternalContext<T>) externalContext;
    }

    void setExternalContext(ExternalContext<?> externalContext) {
        this.externalContext = externalContext;
    }
}
