//
//  ========================================================================
//  Copyright (c) 1995-2020 Mort Bay Consulting Pty Ltd and others.
//  ------------------------------------------------------------------------
//  All rights reserved. This program and the accompanying materials
//  are made available under the terms of the Eclipse Public License v1.0
//  and Apache License v2.0 which accompanies this distribution.
//
//      The Eclipse Public License is available at
//      http://www.eclipse.org/legal/epl-v10.html
//
//      The Apache License v2.0 is available at
//      http://www.opensource.org/licenses/apache2.0.php
//
//  You may elect to redistribute this code under either of these licenses.
//  ========================================================================
//

package org.eclipse.jetty.fcgi.client.http;

import java.io.IOException;
import java.util.Map;

import org.eclipse.jetty.client.AbstractConnectorHttpClientTransport;
import org.eclipse.jetty.client.DuplexConnectionPool;
import org.eclipse.jetty.client.HttpClient;
import org.eclipse.jetty.client.HttpDestination;
import org.eclipse.jetty.client.MultiplexConnectionPool;
import org.eclipse.jetty.client.Origin;
import org.eclipse.jetty.client.api.Connection;
import org.eclipse.jetty.client.api.Request;
import org.eclipse.jetty.fcgi.FCGI;
import org.eclipse.jetty.http.HttpFields;
import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.util.ProcessorUtils;
import org.eclipse.jetty.util.Promise;
import org.eclipse.jetty.util.annotation.ManagedAttribute;
import org.eclipse.jetty.util.annotation.ManagedObject;

@ManagedObject("The FastCGI/1.0 client transport")
public class HttpClientTransportOverFCGI extends AbstractConnectorHttpClientTransport
{
    private final boolean multiplexed;
    private final String scriptRoot;

    public HttpClientTransportOverFCGI(String scriptRoot)
    {
        this(Math.max(1, ProcessorUtils.availableProcessors() / 2), false, scriptRoot);
    }

    public HttpClientTransportOverFCGI(int selectors, boolean multiplexed, String scriptRoot)
    {
        super(selectors);
        this.multiplexed = multiplexed;
        this.scriptRoot = scriptRoot;
        setConnectionPoolFactory(destination ->
        {
            HttpClient httpClient = getHttpClient();
            int maxConnections = httpClient.getMaxConnectionsPerDestination();
            return isMultiplexed()
                ? new MultiplexConnectionPool(destination, maxConnections, destination, httpClient.getMaxRequestsQueuedPerDestination())
                : new DuplexConnectionPool(destination, maxConnections, destination);
        });
    }

    @ManagedAttribute(value = "Whether connections are multiplexed", readonly = true)
    public boolean isMultiplexed()
    {
        return multiplexed;
    }

    @ManagedAttribute(value = "The scripts root directory", readonly = true)
    public String getScriptRoot()
    {
        return scriptRoot;
    }

    @Override
    public HttpDestination newHttpDestination(Origin origin)
    {
        return isMultiplexed() ? new MultiplexHttpDestinationOverFCGI(getHttpClient(), origin)
            : new HttpDestinationOverFCGI(getHttpClient(), origin);
    }

    @Override
    public org.eclipse.jetty.io.Connection newConnection(EndPoint endPoint, Map<String, Object> context) throws IOException
    {
        HttpDestination destination = (HttpDestination)context.get(HTTP_DESTINATION_CONTEXT_KEY);
        @SuppressWarnings("unchecked")
        Promise<Connection> promise = (Promise<Connection>)context.get(HTTP_CONNECTION_PROMISE_CONTEXT_KEY);
        HttpConnectionOverFCGI connection = newHttpConnection(endPoint, destination, promise);
        if (LOG.isDebugEnabled())
            LOG.debug("Created {}", connection);
        return customize(connection, context);
    }

    protected HttpConnectionOverFCGI newHttpConnection(EndPoint endPoint, HttpDestination destination, Promise<Connection> promise)
    {
        return new HttpConnectionOverFCGI(endPoint, destination, promise, isMultiplexed());
    }

    protected void customize(Request request, HttpFields fastCGIHeaders)
    {
        fastCGIHeaders.put(FCGI.Headers.DOCUMENT_ROOT, getScriptRoot());
    }
}
