/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.hc.core5.http.nio.command;

import java.util.concurrent.atomic.AtomicBoolean;

import org.apache.hc.core5.annotation.Internal;
import org.apache.hc.core5.concurrent.CancellableDependency;
import org.apache.hc.core5.function.Callback;
import org.apache.hc.core5.http.RequestNotExecutedException;
import org.apache.hc.core5.http.StreamControl;
import org.apache.hc.core5.http.nio.AsyncClientExchangeHandler;
import org.apache.hc.core5.http.nio.AsyncPushConsumer;
import org.apache.hc.core5.http.nio.HandlerFactory;
import org.apache.hc.core5.http.protocol.HttpContext;
import org.apache.hc.core5.util.Args;

/**
 * Request execution command.
 *
 * @since 5.0
 */
@Internal
public final class RequestExecutionCommand extends ExecutableCommand {

    private final AsyncClientExchangeHandler exchangeHandler;
    private final HandlerFactory<AsyncPushConsumer> pushHandlerFactory;
    private final CancellableDependency cancellableDependency;
    private final HttpContext context;
    private final Callback<StreamControl> initiationCallback;
    private final AtomicBoolean failed;

    /**
     * @since 5.5
     */
    public RequestExecutionCommand(
            final AsyncClientExchangeHandler exchangeHandler,
            final HandlerFactory<AsyncPushConsumer> pushHandlerFactory,
            final HttpContext context,
            final Callback<StreamControl> initiationCallback) {
        this.exchangeHandler = Args.notNull(exchangeHandler, "Handler");
        this.pushHandlerFactory = pushHandlerFactory;
        this.initiationCallback = initiationCallback;
        this.cancellableDependency = null;
        this.context = context;
        this.failed = new AtomicBoolean();
    }

    /**
     * @deprecated Not used.
     */
    @Deprecated
    public RequestExecutionCommand(
            final AsyncClientExchangeHandler exchangeHandler,
            final HandlerFactory<AsyncPushConsumer> pushHandlerFactory,
            final CancellableDependency cancellableDependency,
            final HttpContext context) {
        this.exchangeHandler = Args.notNull(exchangeHandler, "Handler");
        this.pushHandlerFactory = pushHandlerFactory;
        this.initiationCallback = null;
        this.cancellableDependency = cancellableDependency;
        this.context = context;
        this.failed = new AtomicBoolean();
    }

    public RequestExecutionCommand(
            final AsyncClientExchangeHandler exchangeHandler,
            final HandlerFactory<AsyncPushConsumer> pushHandlerFactory,
            final HttpContext context) {
        this(exchangeHandler, pushHandlerFactory, context, null);
    }

    public RequestExecutionCommand(
            final AsyncClientExchangeHandler exchangeHandler,
            final HttpContext context) {
        this(exchangeHandler, null, context);
    }

    public AsyncClientExchangeHandler getExchangeHandler() {
        return exchangeHandler;
    }

    public HandlerFactory<AsyncPushConsumer> getPushHandlerFactory() {
        return pushHandlerFactory;
    }

    /**
     * @deprecated no used.
     */
    @Deprecated
    @Override
    public CancellableDependency getCancellableDependency() {
        return cancellableDependency;
    }

    public HttpContext getContext() {
        return context;
    }

    /**
     * @since 5.5
     */
    @SuppressWarnings("deprecated")
    public void initiated(final StreamControl streamControl) {
        if (initiationCallback != null) {
            initiationCallback.execute(streamControl);
        }
        if (cancellableDependency != null) {
            cancellableDependency.setDependency(streamControl);
        }
    }

    @Override
    public void failed(final Exception ex) {
        if (failed.compareAndSet(false, true)) {
            try {
                exchangeHandler.failed(ex);
            } finally {
                exchangeHandler.releaseResources();
            }
        }
    }

    @Override
    public boolean cancel() {
        if (failed.compareAndSet(false, true)) {
            try {
                exchangeHandler.failed(new RequestNotExecutedException());
                return true;
            } finally {
                exchangeHandler.releaseResources();
            }
        }
        return false;
    }

}
