#include "RemoteRunner.h"
#include "Message.h"

#include <QCoreApplication>

#include <unistd.h>

RemoteRunner::RemoteRunner(int inputId, int outputId)
    : m_thread(inputId),
      m_outputId(outputId)
{
    connect (&m_thread, SIGNAL(receivedMessage(QByteArray)),
             this, SIGNAL(receivedMessage(QByteArray)), Qt::QueuedConnection);

    m_thread.start();
}

RemoteRunner::~RemoteRunner()
{
    m_thread.closeConnection();
    m_thread.wait();
}

void RemoteRunner::runRemote(const Message &message) const
{
    assert(message.size() > 0);
    assert(message.size() < 0x7FFF);
    char sizeIndicator[2];
    uint32_t messageSize = message.size();
    sizeIndicator[0] = messageSize;
    sizeIndicator[1] = messageSize >> 8;
    write(m_outputId, sizeIndicator, 2);
    write(m_outputId, message.begin(), message.size());
}


// ///////////////////////////////////////////

RemoteRunnerPrivate::RemoteRunnerPrivate(int inputId)
    : m_inputId(inputId)
{
}

void RemoteRunnerPrivate::closeConnection()
{
    close (m_inputId);
}

void RemoteRunnerPrivate::run()
{
    char buf[1000];
    char *start = buf;
    size_t offset = 0;
    while (true) {
        ssize_t amount = read(m_inputId, buf + offset, sizeof(buf) - offset);
        if (amount <= 0) {
            // printf("remote runner private got read: %ld, closing down\n", amount);
            QCoreApplication::quit();
            return;
        }
        offset += amount;
        const char *end = buf + offset;
        for (char *i = start; i < end; ++i) {
            if (*i == 0) {
                QByteArray bytes(start, i - start);
                emit receivedMessage(bytes);
                start = i + 1;
            }
        }

        if (start >= end) {
            start = buf;
            offset = 0;
        }
        else if (start > buf) {
            // compact: move unconsumed data to beginning
            assert(end >= start); // don't let offset get negative
            offset = end - start;
            memmove(buf, start, offset);
            start = buf;
        }
        else if (offset >= sizeof(buf))
            throw std::runtime_error("Too long message on Pipe");
    }
}