/*
 * Copyright (c) 1998-2004, Index Data.
 * See the file LICENSE for details.
 * 
 * $Id: yaz-pdu-assoc.cpp,v 1.46 2006/03/30 11:58:00 adam Exp $
 */

#include <assert.h>
#include <string.h>
#include <yaz/log.h>
#include <yaz/tcpip.h>

#include <yazpp/pdu-assoc.h>

using namespace yazpp_1;

void PDU_Assoc::init(ISocketObservable *socketObservable)
{
    m_state = Closed;
    m_cs = 0;
    m_socketObservable = socketObservable;
    m_PDU_Observer = 0;
    m_queue_out = 0;
    m_queue_in = 0;
    m_input_buf = 0;
    m_input_len = 0;
    m_children = 0;
    m_parent = 0;
    m_next = 0;
    m_destroyed = 0;
    m_idleTime = 0;
    m_log = YLOG_DEBUG;
}

PDU_Assoc::PDU_Assoc(ISocketObservable *socketObservable)
{
    init (socketObservable);
}

PDU_Assoc::PDU_Assoc(ISocketObservable *socketObservable,
                     COMSTACK cs)
{
    init(socketObservable);
    m_cs = cs;
    unsigned mask = 0;
    if (cs->io_pending & CS_WANT_WRITE)
        mask |= SOCKET_OBSERVE_WRITE;
    if (cs->io_pending & CS_WANT_READ)
        mask |= SOCKET_OBSERVE_READ;
    m_socketObservable->addObserver(cs_fileno(cs), this);
    if (!mask)
    {
        yaz_log (m_log, "new PDU_Assoc. Ready");
        m_state = Ready;
        flush_PDU();
    }
    else
    {
        yaz_log (m_log, "new PDU_Assoc. Accepting");
        // assume comstack is accepting...
        m_state = Accepting;
        m_socketObservable->addObserver(cs_fileno(cs), this);
        yaz_log(m_log, "maskObserver 1");
        m_socketObservable->maskObserver(this,
                                         mask |SOCKET_OBSERVE_EXCEPT);
    }
}


IPDU_Observable *PDU_Assoc::clone()
{
    PDU_Assoc *copy = new PDU_Assoc(m_socketObservable);
    return copy;
}

void PDU_Assoc::socketNotify(int event)
{
    yaz_log (m_log, "PDU_Assoc::socketNotify p=%p state=%d event = %d",
          this, m_state, event);
    if (event & SOCKET_OBSERVE_EXCEPT)
    {
        close();
        m_PDU_Observer->failNotify();
        return;
    }
    else if (event & SOCKET_OBSERVE_TIMEOUT)
    {
        m_PDU_Observer->timeoutNotify();
        return;
    }
    switch (m_state)
    {
    case Accepting:
        if (!cs_accept (m_cs))
        {
            yaz_log (m_log, "PDU_Assoc::cs_accept failed");
            m_cs = 0;
            close();
            m_PDU_Observer->failNotify();
        }
        else
        {
            unsigned mask = 0;
            if (m_cs->io_pending & CS_WANT_WRITE)
                mask |= SOCKET_OBSERVE_WRITE;
            if (m_cs->io_pending & CS_WANT_READ)
                mask |= SOCKET_OBSERVE_READ;
            if (!mask)
            {   // accept is complete. turn to ready state and write if needed
                m_state = Ready;
                flush_PDU();
            }
            else  
            {   // accept still incomplete.
                yaz_log(m_log, "maskObserver 2");
                m_socketObservable->maskObserver(this,
                                             mask|SOCKET_OBSERVE_EXCEPT);
            }
        }
        break;
    case Connecting:
        if (event & SOCKET_OBSERVE_READ && 
            event & SOCKET_OBSERVE_WRITE)
        {
            // For Unix: if both read and write is set, then connect failed.
            close();
            m_PDU_Observer->failNotify();
        }
        else
        {
            yaz_log (m_log, "cs_rcvconnect");
            int res = cs_rcvconnect (m_cs);
            if (res == 1)
            {
                unsigned mask = SOCKET_OBSERVE_EXCEPT;
                if (m_cs->io_pending & CS_WANT_WRITE)
                    mask |= SOCKET_OBSERVE_WRITE;
                if (m_cs->io_pending & CS_WANT_READ)
                    mask |= SOCKET_OBSERVE_READ;
                yaz_log(m_log, "maskObserver 3");
                m_socketObservable->maskObserver(this, mask);
            }
            else
            {
                m_state = Ready;
                if (m_PDU_Observer)
                    m_PDU_Observer->connectNotify();
                flush_PDU();
            }
        }
        break;
    case Listen:
        if (event & SOCKET_OBSERVE_READ)
        {
            int res;
            COMSTACK new_line;
            
            if ((res = cs_listen(m_cs, 0, 0)) == 1)
                return;
            if (res < 0)
            {
                yaz_log(YLOG_FATAL|YLOG_ERRNO, "cs_listen failed");
                return;
            }
            if (!(new_line = cs_accept(m_cs)))
                return;
            /* 1. create socket-manager 
               2. create pdu-assoc
               3. create top-level object
                    setup observer for child fileid in pdu-assoc
               4. start thread
            */
            yaz_log (m_log, "new session: parent fd=%d child fd=%d",
                     cs_fileno(m_cs), cs_fileno(new_line));
            childNotify (new_line);
        }
        break;
    case Writing:
        if (event & (SOCKET_OBSERVE_READ|SOCKET_OBSERVE_WRITE))
            flush_PDU();
        break;
    case Ready:
        if (event & (SOCKET_OBSERVE_READ|SOCKET_OBSERVE_WRITE))
        {
            do
            {
                int res = cs_get (m_cs, &m_input_buf, &m_input_len);
                if (res == 1)
                {
                    unsigned mask = SOCKET_OBSERVE_EXCEPT;
                    if (m_cs->io_pending & CS_WANT_WRITE)
                        mask |= SOCKET_OBSERVE_WRITE;
                    if (m_cs->io_pending & CS_WANT_READ)
                        mask |= SOCKET_OBSERVE_READ;
                    yaz_log(m_log, "maskObserver 4");
                    m_socketObservable->maskObserver(this, mask);
                    return;
                }
                else if (res <= 0)
                {
                    yaz_log (m_log, "PDU_Assoc::Connection closed by peer");
                    close();
                    if (m_PDU_Observer)
                        m_PDU_Observer->failNotify(); // problem here..
                    return;
                }
                // lock it, so we know if recv_PDU deletes it.
                int destroyed = 0;
                m_destroyed = &destroyed;

                if (!m_PDU_Observer)
                    return;
#if 0
                PDU_Queue **pq = &m_queue_in;
                while (*pq)
                    pq = &(*pq)->m_next;
                
                *pq = new PDU_Queue(m_input_buf, res);
#else
                m_PDU_Observer->recv_PDU(m_input_buf, res);
#endif
                if (destroyed)   // it really was destroyed, return now.
                    return;
                m_destroyed = 0;
            } while (m_cs && cs_more (m_cs));
            if (m_cs && m_state == Ready)
            {
                yaz_log(m_log, "maskObserver 5");
                m_socketObservable->maskObserver(this,
                                                 SOCKET_OBSERVE_EXCEPT|
                                                 SOCKET_OBSERVE_READ);
            }
        }
        break;
    case Closed:
        yaz_log (m_log, "CLOSING state=%d event was %d", m_state, event);
        close();
        m_PDU_Observer->failNotify();
        break;
    default:
        yaz_log (m_log, "Unknown state=%d event was %d", m_state, event);
        close();
        m_PDU_Observer->failNotify();
    }
}

void PDU_Assoc::close()
{
    PDU_Assoc *ch;
    for (ch = m_children; ch; ch = ch->m_next)
        ch->close();

    m_socketObservable->deleteObserver(this);
    m_state = Closed;
    if (m_cs)
    {
        yaz_log (m_log, "PDU_Assoc::close fd=%d", cs_fileno(m_cs));
        cs_close (m_cs);
    }
    m_cs = 0;
    while (m_queue_out)
    {
        PDU_Queue *q_this = m_queue_out;
        m_queue_out = m_queue_out->m_next;
        delete q_this;
    }
    xfree (m_input_buf);
    m_input_buf = 0;
    m_input_len = 0;
}

void PDU_Assoc::destroy()
{
    close();

    if (m_destroyed)
        *m_destroyed = 1;
    PDU_Assoc **c;

    // delete from parent's child list (if any)
    if (m_parent)
    {
        c = &m_parent->m_children;
        while (*c != this)
        {
            assert (*c);
            c = &(*c)->m_next;
        }
        *c = (*c)->m_next;
    }
    // delete all children ...
    c = &m_children;
    while (*c)
    {
        PDU_Assoc *here = *c;
        *c = (*c)->m_next;
        here->m_parent = 0;
        delete here;
    }
    yaz_log (m_log, "PDU_Assoc::destroy this=%p", this);
}

PDU_Assoc::PDU_Queue::PDU_Queue(const char *buf, int len)
{
    m_buf = (char *) xmalloc (len);
    memcpy (m_buf, buf, len);
    m_len = len;
    m_next = 0;
}

PDU_Assoc::PDU_Queue::~PDU_Queue()
{
    xfree (m_buf);
}

int PDU_Assoc::flush_PDU()
{
    int r;
    
    if (m_state != Ready && m_state != Writing)
    {
        yaz_log (m_log, "YAZ_PDU_Assoc::flush_PDU, not ready");
        return 1;
    }
    PDU_Queue *q = m_queue_out;
    if (!q)
    {
        m_state = Ready;
        yaz_log (m_log, "YAZ_PDU_Assoc::flush_PDU queue empty");
        yaz_log(m_log, "maskObserver 6");
        m_socketObservable->maskObserver(this, SOCKET_OBSERVE_READ|
                                         SOCKET_OBSERVE_WRITE|
                                         SOCKET_OBSERVE_EXCEPT);
        return 0;
    }
    r = cs_put (m_cs, q->m_buf, q->m_len);
    if (r < 0)
    {
        yaz_log (m_log, "PDU_Assoc::flush_PDU cs_put failed");
        close();
        m_PDU_Observer->failNotify();
        return r;
    }
    if (r == 1)
    {
        unsigned mask = SOCKET_OBSERVE_EXCEPT;
        m_state = Writing;
        if (m_cs->io_pending & CS_WANT_WRITE)
            mask |= SOCKET_OBSERVE_WRITE;
        if (m_cs->io_pending & CS_WANT_READ)
            mask |= SOCKET_OBSERVE_READ;

        mask |= SOCKET_OBSERVE_WRITE;
        yaz_log(m_log, "maskObserver 7");
        m_socketObservable->maskObserver(this, mask);
        yaz_log (m_log, "PDU_Assoc::flush_PDU cs_put %d bytes fd=%d (inc)",
                 q->m_len, cs_fileno(m_cs));
        return r;
    } 
    yaz_log (m_log, "PDU_Assoc::flush_PDU cs_put %d bytes", q->m_len);
    // whole packet sent... delete this and proceed to next ...
    m_queue_out = q->m_next;
    delete q;
    // don't select on write if queue is empty ...
    if (!m_queue_out)
    {
        m_state = Ready;
        yaz_log(m_log, "maskObserver 8");
        m_socketObservable->maskObserver(this, SOCKET_OBSERVE_READ|
                                         SOCKET_OBSERVE_EXCEPT);
    }
    return r;
}

int PDU_Assoc::send_PDU(const char *buf, int len)
{
    yaz_log (m_log, "PDU_Assoc::send_PDU");
    PDU_Queue **pq = &m_queue_out;
    int is_idle = (*pq ? 0 : 1);
    
    if (!m_cs)
    {
        yaz_log (m_log, "PDU_Assoc::send_PDU failed, m_cs == 0");
        return -1;
    }
    while (*pq)
        pq = &(*pq)->m_next;
    *pq = new PDU_Queue(buf, len);
    if (is_idle)
        return flush_PDU ();
    else
        yaz_log (m_log, "PDU_Assoc::cannot send_PDU fd=%d",
                 cs_fileno(m_cs));
    return 0;
}

COMSTACK PDU_Assoc::comstack(const char *type_and_host, void **vp)
{
    return cs_create_host(type_and_host, 2, vp);
}

int PDU_Assoc::listen(IPDU_Observer *observer, const char *addr)
{
    close();

    m_PDU_Observer = observer;
    void *ap;
    m_cs = comstack(addr, &ap);

    if (!m_cs)
        return -1;
    if (cs_bind(m_cs, ap, CS_SERVER) < 0)
        return -2;
    m_socketObservable->addObserver(cs_fileno(m_cs), this);
    yaz_log(m_log, "maskObserver 9");
    m_socketObservable->maskObserver(this, SOCKET_OBSERVE_READ|
                                     SOCKET_OBSERVE_EXCEPT);
    yaz_log (m_log, "PDU_Assoc::listen ok fd=%d", cs_fileno(m_cs));
    m_state = Listen;
    return 0;
}

void PDU_Assoc::idleTime(int idleTime)
{
    m_idleTime = idleTime;
    yaz_log (m_log, "PDU_Assoc::idleTime(%d)", idleTime);
    m_socketObservable->timeoutObserver(this, m_idleTime);
}

int PDU_Assoc::connect(IPDU_Observer *observer, const char *addr)
{
    yaz_log (m_log, "PDU_Assoc::connect %s", addr);
    close();
    m_PDU_Observer = observer;
    void *ap;
    m_cs = comstack(addr, &ap);
    if (!m_cs)
        return -1;
    int res = cs_connect (m_cs, ap);
    yaz_log (m_log, "PDU_Assoc::connect fd=%d res=%d", cs_fileno(m_cs),
             res);
    m_socketObservable->addObserver(cs_fileno(m_cs), this);

    if (res == 0)
    {   // Connect complete
        m_state = Connecting;
        unsigned mask = SOCKET_OBSERVE_EXCEPT;
        mask |= SOCKET_OBSERVE_WRITE;
        mask |= SOCKET_OBSERVE_READ;
        yaz_log(m_log, "maskObserver 11");
        m_socketObservable->maskObserver(this, mask);
    }
    else if (res > 0)
    {   // Connect pending
        m_state = Connecting;
        unsigned mask = SOCKET_OBSERVE_EXCEPT;
        if (m_cs->io_pending & CS_WANT_WRITE)
            mask |= SOCKET_OBSERVE_WRITE;
        if (m_cs->io_pending & CS_WANT_READ)
            mask |= SOCKET_OBSERVE_READ;
        yaz_log(m_log, "maskObserver 11");
        m_socketObservable->maskObserver(this, mask);
    }
    else
    {   // Connect failed immediately
        // Since m_state is Closed we can distinguish this case from
        // normal connect in socketNotify handler
        yaz_log(m_log, "maskObserver 12");
        m_socketObservable->maskObserver(this, SOCKET_OBSERVE_WRITE|
                                         SOCKET_OBSERVE_EXCEPT);
    }
    return 0;
}

// Single-threaded... Only useful for non-blocking handlers
void PDU_Assoc::childNotify(COMSTACK cs)
{
    PDU_Assoc *new_observable =
        new PDU_Assoc (m_socketObservable, cs);
    
    // Clone PDU Observer
    new_observable->m_PDU_Observer = m_PDU_Observer->sessionNotify
        (new_observable, cs_fileno(cs));

    if (!new_observable->m_PDU_Observer)
    {
        new_observable->close();
        delete new_observable;
        return;
    }
    new_observable->m_next = m_children;
    m_children = new_observable;
    new_observable->m_parent = this;
}

const char*PDU_Assoc::getpeername()
{
    if (!m_cs)
        return 0;
    return cs_addrstr(m_cs);
}
/*
 * Local variables:
 * c-basic-offset: 4
 * indent-tabs-mode: nil
 * End:
 * vim: shiftwidth=4 tabstop=8 expandtab
 */