/*

 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.incubator.http;

import java.io.IOException;

import java.net.InetSocketAddress;

import java.nio.ByteBuffer;

import java.nio.channels.SocketChannel;

import java.util.concurrent.CompletableFuture;

import javax.net.ssl.SSLEngineResult.Status;

import javax.net.ssl.SSLParameters;

import jdk.incubator.http.SSLDelegate.WrapperResult;

import jdk.incubator.http.internal.common.ByteBufferReference;

import jdk.incubator.http.internal.common.MinimalFuture;

import jdk.incubator.http.internal.common.Utils;

/**

 * An SSL connection built on a Plain TCP connection.

 */

class SSLConnection extends HttpConnection {

    PlainHttpConnection delegate;

    SSLDelegate sslDelegate;

    final String[] alpn;

    final String serverName;

    @Override

    public CompletableFuture<Void> connectAsync() {

        return delegate.connectAsync()

                .thenCompose((Void v) ->

                                MinimalFuture.supply( () -> {

                                    this.sslDelegate = new SSLDelegate(delegate.channel(), client, alpn, serverName);

                                    return null;

                                }));

    }

    @Override

    public void connect() throws IOException {

        delegate.connect();

        this.sslDelegate = new SSLDelegate(delegate.channel(), client, alpn, serverName);

    }

    SSLConnection(InetSocketAddress addr, HttpClientImpl client, String[] ap) {

        super(addr, client);

        this.alpn = ap;

        this.serverName = Utils.getServerName(addr);

        delegate = new PlainHttpConnection(addr, client);

    }

    /**

     * Create an SSLConnection from an existing connected AsyncSSLConnection.

     * Used when downgrading from HTTP/2 to HTTP/1.1

     */

    SSLConnection(AsyncSSLConnection c) {

        super(c.address, c.client);

        this.delegate = c.plainConnection();

        AsyncSSLDelegate adel = c.sslDelegate();

        this.sslDelegate = new SSLDelegate(adel.engine, delegate.channel(), client, adel.serverName);

        this.alpn = adel.alpn;

        this.serverName = adel.serverName;

    }

    @Override

    SSLParameters sslParameters() {

        return sslDelegate.getSSLParameters();

    }

    @Override

    public String toString() {

        return "SSLConnection: " + super.toString();

    }

    private static long countBytes(ByteBuffer[] buffers, int start, int length) {

        long c = 0;

        for (int i=0; i<length; i++) {

            c+= buffers[start+i].remaining();

        }

        return c;

    }

    @Override

    ConnectionPool.CacheKey cacheKey() {

        return ConnectionPool.cacheKey(address, null);

    }

    @Override

    long write(ByteBuffer[] buffers, int start, int number) throws IOException {

        //debugPrint("Send", buffers, start, number);

        long l = countBytes(buffers, start, number);

        WrapperResult r = sslDelegate.sendData(buffers, start, number);

        if (r.result.getStatus() == Status.CLOSED) {

            if (l > 0) {

                throw new IOException("SSLHttpConnection closed");

            }

        }

        return l;

    }

    @Override

    long write(ByteBuffer buffer) throws IOException {

        //debugPrint("Send", buffer);

        long l = buffer.remaining();

        WrapperResult r = sslDelegate.sendData(buffer);

        if (r.result.getStatus() == Status.CLOSED) {

            if (l > 0) {

                throw new IOException("SSLHttpConnection closed");

            }

        }

        return l;

    }

    @Override

    void writeAsync(ByteBufferReference[] buffers) throws IOException {

        write(ByteBufferReference.toBuffers(buffers), 0, buffers.length);

    }

    @Override

    void writeAsyncUnordered(ByteBufferReference[] buffers) throws IOException {

        write(ByteBufferReference.toBuffers(buffers), 0, buffers.length);

    }

    @Override

    void flushAsync() throws IOException {

        // nothing to do

    }

    @Override

    public void close() {

        Utils.close(delegate.channel());

    }

    @Override

    void shutdownInput() throws IOException {

        delegate.channel().shutdownInput();

    }

    @Override

    void shutdownOutput() throws IOException {

        delegate.channel().shutdownOutput();

    }

    @Override

    protected ByteBuffer readImpl() throws IOException {

        WrapperResult r = sslDelegate.recvData(ByteBuffer.allocate(8192));

        // TODO: check for closure

        int n = r.result.bytesProduced();

        if (n > 0) {

            return r.buf;

        } else if (n == 0) {

            return Utils.EMPTY_BYTEBUFFER;

        } else {

            return null;

        }

    }

    @Override

    boolean connected() {

        return delegate.connected();

    }

    @Override

    SocketChannel channel() {

        return delegate.channel();

    }

    @Override

    CompletableFuture<Void> whenReceivingResponse() {

        return delegate.whenReceivingResponse();

    }

    @Override

    boolean isSecure() {

        return true;

    }

    @Override

    boolean isProxied() {

        return false;

    }

}