// Copyright (c) 2012 by István Váradi

// This file is part of libxplcommon, a common utility library for
// development related to X-Plane

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:

// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// The views and conclusions contained in the software and documentation are those
// of the authors and should not be interpreted as representing official policies,
// either expressed or implied, of the FreeBSD Project.

//------------------------------------------------------------------------------

#include <xplcommon/Thread.h>
#include <xplcommon/Waiter.h>
#include <xplcommon/LocalServerSocket.h>
#include <xplcommon/LocalAcceptor.h>
#include <xplcommon/LocalSocket.h>
#include <xplcommon/LocalClientSocket.h>
#include <xplcommon/Connector.h>
#include <xplcommon/ReadingBuffer.h>
#include <xplcommon/WritingBuffer.h>
#include <xplcommon/WaitableEvent.h>

#include <cstdlib>
#include <cstdio>
#include <cassert>

#include <signal.h>

#include <sys/time.h>

//------------------------------------------------------------------------------

using xplcommon::Thread;
using xplcommon::Waiter;
using xplcommon::LocalServerSocket;
using xplcommon::LocalAcceptor;
using xplcommon::LocalSocket;
using xplcommon::LocalClientSocket;
using xplcommon::Connector;
using xplcommon::ReadingBuffer;
using xplcommon::WritingBuffer;
using xplcommon::WaitableEvent;

using std::min;

//------------------------------------------------------------------------------

void communicate(ReadingBuffer& readingBuffer, WritingBuffer& writingBuffer,
                 Waiter& waiter, unsigned seed, const char* prefix,
                 WaitableEvent* quitEvent = 0)
{
    static const size_t minToWrite = 2076;
    static const size_t maxToWrite = 1345670;
    static const size_t rangeToWrite = maxToWrite - minToWrite;

    static const size_t reportingInterval = 100000;

    static const int sleepThreshold = static_cast<int>(RAND_MAX * 0.95);
    static const int sleepRemainder = RAND_MAX - sleepThreshold;
    static const unsigned minSleep = 10;
    static const unsigned maxSleep = 250;
    static const unsigned sleepRange = maxSleep - minSleep;

    size_t numBytesRead = 0;
    size_t nextReportRead = reportingInterval;
    size_t numWriteBlocked = 0;
    size_t numBytesWritten = 0;
    size_t nextReportWritten = reportingInterval;
    size_t numReadBlocked = 0;
    size_t numMillisSlept = 0;

    bool toQuit = false;

    while(!toQuit) {
        int r = rand_r(&seed);
        size_t toWrite = minToWrite +
            static_cast<size_t>( static_cast<double>(r) *
                                 rangeToWrite / RAND_MAX );

        while(toWrite>0) {
            writingBuffer.reset();
            size_t length = min(writingBuffer.getCapacity(), toWrite);
            writingBuffer.addLength(length);

            if (quitEvent!=0 && quitEvent->check()) {
                toQuit = true;
                break;
            }

            if (writingBuffer.write()) {
                numBytesWritten += length;
                toWrite -= length;
                length = 0;

                if (numBytesWritten>=nextReportWritten) {
                    printf("%s: written %zu bytes with %zu blocking and %zu ms sleeping\n",
                           prefix, numBytesWritten, numWriteBlocked,
                           numMillisSlept);
                    nextReportWritten += reportingInterval;
                }
            } else if (writingBuffer.failed()) {
                printf("%s: writing failed with error: %lu\n",
                       prefix,
                       static_cast<unsigned long>(writingBuffer.getErrorCode()));
                toQuit = true;
                break;
            } else {
                ++numWriteBlocked;
            }

            if (readingBuffer.read()) {
                numBytesRead += readingBuffer.getLength();
                if (numBytesRead>=nextReportRead) {
                    printf("%s: read %zu bytes with %zu blocking and %zu ms sleeping\n",
                           prefix, numBytesRead, numReadBlocked, numMillisSlept);
                    nextReportRead += reportingInterval;
                }
                readingBuffer.reset();
            } else if (readingBuffer.failed()) {
                printf("%s: reading failed with error: %lu\n",
                       prefix,
                       static_cast<unsigned long>(readingBuffer.getErrorCode()));
                toQuit = true;
                break;
            } else {
                ++numReadBlocked;
            }

            r = rand_r(&seed);
            if (r>=sleepThreshold) {
                unsigned toSleep = minSleep +
                    static_cast<unsigned>(static_cast<double>(r - sleepThreshold) *
                                          sleepRange / sleepRemainder);
                assert(toSleep>=minSleep);
                assert(toSleep<maxSleep);
                Thread::sleep(toSleep);
                numMillisSlept += toSleep;
            }

            if (length!=0) {
                waiter.wait();
                if (waiter.failed()) {
                    printf("%s: waiting failed with error: %lu\n",
                           prefix,
                           static_cast<unsigned long>(waiter.getErrorCode()));
                    toQuit = true;
                    break;
                }
            }
        }
    }

    printf("%s: written %zu bytes with %zu blocking\n",
           prefix, numBytesWritten, numWriteBlocked);
    printf("%s: read %zu bytes with %zu blocking\n",
           prefix, numBytesRead, numReadBlocked);
    printf("%s: slept %zu ms\n", prefix, numMillisSlept);
}

//------------------------------------------------------------------------------

class ServerThread : public Thread
{
private:
    Waiter waiter;

    WaitableEvent event;

public:
    ServerThread();

    void signal();

    virtual void run();
};

//------------------------------------------------------------------------------

ServerThread::ServerThread() :
    event(&waiter)
{
}

//------------------------------------------------------------------------------

void ServerThread::signal()
{
    event.fire();
}

//------------------------------------------------------------------------------

void ServerThread::run()
{
    unsigned seed = static_cast<unsigned>(time(0)*1.2);
    printf("ServerThread::run: seed=%u\n", seed);

    LocalServerSocket serverSocket("test", &waiter);
    LocalAcceptor& acceptor = serverSocket.getAcceptor();

    while(!acceptor.accept()) {
        if (acceptor.failed()) {
            printf("ServerThread::run: acceptor failed...\n");
            return;
        }
        printf("ServerThread::run: waiting...\n");
        waiter.wait();
    }

    printf("ServerThread::run: waiting done, received connection\n");
    LocalSocket* socket = acceptor.getSocket();

    communicate(socket->getReadingBuffer(), socket->getWritingBuffer(),
                waiter, seed, "ServerThread", &event);


    delete socket;
}

//------------------------------------------------------------------------------
//------------------------------------------------------------------------------

class ClientThread : public Thread
{
public:
    virtual void run();
};

//------------------------------------------------------------------------------

void ClientThread::run()
{
    unsigned seed = static_cast<unsigned>(time(0)*1.8);
    printf("ClientThread::run: seed=%u\n", seed);

    printf("ClientThread::run: sleeping\n");
    sleep(500);
    printf("ClientThread::run: connecting\n");

    Waiter waiter;

    LocalClientSocket socket("test", &waiter);

    Connector& connector = socket.getConnector();

    while(!connector.connect()) {
        if (connector.failed()) {
            printf("ClientThread::run: connector failed...\n");
            return;
        }
        printf("ClientThread::run: waiting...\n");
        waiter.wait();
    }

    printf("ClientThread::run: connected\n");

    communicate(socket.getReadingBuffer(), socket.getWritingBuffer(),
                waiter, seed, "ClientThread");
}

//------------------------------------------------------------------------------
//------------------------------------------------------------------------------

int main()
{
    signal(SIGPIPE, SIG_IGN);

    ServerThread serverThread;
    ClientThread clientThread;

    printf("Starting threads\n");
    serverThread.start();
    clientThread.start();

    Thread::sleep(60000);
    serverThread.signal();
    printf("Signalled the server thread\n");

    printf("Waiting for the client thread\n");
    clientThread.join();
    printf("Waiting for the server thread\n");
    serverThread.join();
    printf("Both threads returned\n");

    return 0;
}

//------------------------------------------------------------------------------

// Local Variables:
// mode: C++
// c-basic-offset: 4
// indent-tabs-mode: nil
// End: