/*
 * Copyright (C) 2005-2007 by Pieter Palmers
 *
 * This file is part of FFADO
 * FFADO = Free Firewire (pro-)audio drivers for linux
 *
 * FFADO is based upon FreeBoB.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "IsoHandler.h"
#include "ieee1394service.h" 

#include "libstreaming/generic/StreamProcessor.h"
#include "libutil/PosixThread.h"

#include <errno.h>
#include <netinet/in.h>
#include <assert.h>
#include <unistd.h>
#include <string.h>

#include <iostream>
using namespace std;
using namespace Streaming;

IMPL_DEBUG_MODULE( IsoHandler, IsoHandler, DEBUG_LEVEL_NORMAL );

/* the C callbacks */
enum raw1394_iso_disposition
IsoHandler::iso_transmit_handler(raw1394handle_t handle,
        unsigned char *data, unsigned int *length,
        unsigned char *tag, unsigned char *sy,
        int cycle, unsigned int dropped) {

    IsoHandler *xmitHandler = static_cast<IsoHandler *>(raw1394_get_userdata(handle));
    assert(xmitHandler);

    return xmitHandler->getPacket(data, length, tag, sy, cycle, dropped);
}

enum raw1394_iso_disposition
IsoHandler::iso_receive_handler(raw1394handle_t handle, unsigned char *data,
                        unsigned int length, unsigned char channel,
                        unsigned char tag, unsigned char sy, unsigned int cycle,
                        unsigned int dropped) {

    IsoHandler *recvHandler = static_cast<IsoHandler *>(raw1394_get_userdata(handle));
    assert(recvHandler);

    return recvHandler->putPacket(data, length, channel, tag, sy, cycle, dropped);
}

int IsoHandler::busreset_handler(raw1394handle_t handle, unsigned int generation)
{
    debugOutput( DEBUG_LEVEL_VERBOSE, "Busreset happened, generation %d...\n", generation);

    IsoHandler *handler = static_cast<IsoHandler *>(raw1394_get_userdata(handle));
    assert(handler);
    return handler->handleBusReset(generation);
}

IsoHandler::IsoHandler(IsoHandlerManager& manager, enum EHandlerType t)
   : m_manager( manager )
   , m_type ( t )
   , m_handle( 0 )
   , m_buf_packets( 400 )
   , m_max_packet_size( 1024 )
   , m_irq_interval( -1 )
   , m_packetcount( 0 )
   , m_dropped( 0 )
   , m_Client( 0 )
   , m_poll_timeout( 100 )
   , m_realtime ( false )
   , m_priority ( 0 )
   , m_Thread ( NULL )
   , m_speed( RAW1394_ISO_SPEED_400 )
   , m_prebuffers( 0 )
   , m_State( E_Created )
{
}

IsoHandler::IsoHandler(IsoHandlerManager& manager, enum EHandlerType t, 
                       unsigned int buf_packets, unsigned int max_packet_size, int irq)
   : m_manager( manager )
   , m_type ( t )
   , m_handle( 0 )
   , m_buf_packets( buf_packets )
   , m_max_packet_size( max_packet_size )
   , m_irq_interval( irq )
   , m_packetcount( 0 )
   , m_dropped( 0 )
   , m_Client( 0 )
   , m_poll_timeout( 100 )
   , m_realtime ( false )
   , m_priority ( 0 )
   , m_Thread ( NULL )
   , m_speed( RAW1394_ISO_SPEED_400 )
   , m_prebuffers( 0 )
   , m_State( E_Created )
{
}

IsoHandler::IsoHandler(IsoHandlerManager& manager, enum EHandlerType t, unsigned int buf_packets,
                       unsigned int max_packet_size, int irq,
                       enum raw1394_iso_speed speed)
   : m_manager( manager )
   , m_type ( t )
   , m_handle( 0 )
   , m_buf_packets( buf_packets )
   , m_max_packet_size( max_packet_size )
   , m_irq_interval( irq )
   , m_packetcount( 0 )
   , m_dropped( 0 )
   , m_Client( 0 )
   , m_poll_timeout( 100 )
   , m_realtime ( false )
   , m_priority ( 0 )
   , m_Thread ( NULL )
   , m_speed( speed )
   , m_prebuffers( 0 )
   , m_State( E_Created )
{
}

IsoHandler::~IsoHandler() {
    if (m_Thread) {
        m_Thread->Stop();
        delete m_Thread;
    }
// Don't call until libraw1394's raw1394_new_handle() function has been
// fixed to correctly initialise the iso_packet_infos field.  Bug is
// confirmed present in libraw1394 1.2.1.  In any case,
// raw1394_destroy_handle() will do any iso system shutdown required.
//     raw1394_iso_shutdown(m_handle);
    if(m_handle) {
        if (m_State == E_Running) {
            disable();
        }
        raw1394_destroy_handle(m_handle);
    }
}

bool
IsoHandler::Init() {
    debugOutput( DEBUG_LEVEL_VERBOSE, "%p: Init thread...\n", this);
    m_poll_fd.fd = getFileDescriptor();
    m_poll_fd.revents = 0;
    if (isEnabled()) {
        m_poll_fd.events = POLLIN;
    } else {
        m_poll_fd.events = 0;
    }
    return true;
}

bool
IsoHandler::Execute() {
    int err;

    debugOutput( DEBUG_LEVEL_VERY_VERBOSE, "%p: Execute thread...\n", this);
    // bypass if not running
    if (m_State != E_Running) {
        debugOutput( DEBUG_LEVEL_VERBOSE, "%p: not polling since not running...\n", this);
        usleep(m_poll_timeout * 1000);
        debugOutput( DEBUG_LEVEL_VERBOSE, "%p: done sleeping...\n", this);
        return true;
    }

    err = poll(&m_poll_fd, 1, m_poll_timeout);
    if (err == -1) {
        if (errno == EINTR) {
            return true;
        }
        debugFatal("%p, poll error: %s\n", this, strerror (errno));
        return false;
    }
    if(m_poll_fd.revents & (POLLIN)) {
        if(raw1394_loop_iterate(m_handle)) {
            debugOutput( DEBUG_LEVEL_VERBOSE,
                        "IsoHandler (%p): Failed to iterate handler: %s\n",
                        this,strerror(errno));
            return false;
        }
    } else {
        if (m_poll_fd.revents & POLLERR) {
            debugWarning("error on fd for %p\n", this);
        }
        if (m_poll_fd.revents & POLLHUP) {
            debugWarning("hangup on fd for %p\n",this);
        }
    }
    return true;
}

bool
IsoHandler::setThreadParameters(bool rt, int priority) {
    debugOutput( DEBUG_LEVEL_VERBOSE, "(%p) switch to: (rt=%d, prio=%d)...\n", this, rt, priority);
    if (priority > 98) priority = 98; // cap the priority
    m_realtime = rt;
    m_priority = priority;

    if (m_Thread) {
        if (m_realtime) {
            m_Thread->AcquireRealTime(m_priority);
        } else {
            m_Thread->DropRealTime();
        }
    }
    return true;
}

bool
IsoHandler::init()
{
    debugOutput( DEBUG_LEVEL_VERBOSE, "IsoHandler (%p) enter...\n",this);
    // check the state
    if(m_State != E_Created) {
        debugError("Incorrect state, expected E_Created, got %d\n",(int)m_State);
        return false;
    }

    // the main handle for the ISO traffic
    m_handle = raw1394_new_handle_on_port( m_manager.get1394Service().getPort() );
    if ( !m_handle ) {
        if ( !errno ) {
            debugError("libraw1394 not compatible\n");
        } else {
            debugError("Could not get 1394 handle: %s\n", strerror(errno) );
            debugError("Are ieee1394 and raw1394 drivers loaded?\n");
        }
        return false;
    }
    raw1394_set_userdata(m_handle, static_cast<void *>(this));

    // bus reset handling
    if(raw1394_busreset_notify (m_handle, RAW1394_NOTIFY_ON)) {
        debugWarning("Could not enable busreset notification.\n");
        debugWarning(" Error message: %s\n",strerror(errno));
        debugWarning("Continuing without bus reset support.\n");
    } else {
        // apparently this cannot fail
        raw1394_set_bus_reset_handler(m_handle, busreset_handler);
    }

    // create a thread to iterate ourselves
    debugOutput( DEBUG_LEVEL_VERBOSE, "Start thread for %p...\n", this);
    m_Thread = new Util::PosixThread(this, m_realtime, m_priority, 
                                     PTHREAD_CANCEL_DEFERRED);
    if(!m_Thread) {
        debugFatal("No thread\n");
        return false;
    }
    if (m_Thread->Start() != 0) {
        debugFatal("Could not start update thread\n");
        return false;
    }

    // update the internal state
    m_State=E_Initialized;
    return true;
}

bool IsoHandler::disable()
{
    debugOutput( DEBUG_LEVEL_VERBOSE, "enter...\n");

    // check state
    if(m_State == E_Prepared) return true;
    if(m_State != E_Running) {
        debugError("Incorrect state, expected E_Running, got %d\n",(int)m_State);
        return false;
    }

    m_poll_fd.events = 0;

    // this is put here to try and avoid the
    // Runaway context problem
    // don't know if it will help though.
    raw1394_iso_xmit_sync(m_handle);
    raw1394_iso_stop(m_handle);
    m_State = E_Prepared;
    return true;
}

/**
 * Bus reset handler
 *
 * @return ?
 */

int
IsoHandler::handleBusReset(unsigned int generation)
{
    debugOutput( DEBUG_LEVEL_VERBOSE, "bus reset...\n");

    #define CSR_CYCLE_TIME            0x200
    #define CSR_REGISTER_BASE  0xfffff0000000ULL
    // do a simple read on ourself in order to update the internal structures
    // this avoids read failures after a bus reset
    quadlet_t buf=0;
    raw1394_read(m_handle, raw1394_get_local_id(m_handle),
                 CSR_REGISTER_BASE | CSR_CYCLE_TIME, 4, &buf);
    return 0;
}

void IsoHandler::dumpInfo()
{
    int channel=-1;
    if (m_Client) channel=m_Client->getChannel();

    debugOutputShort( DEBUG_LEVEL_NORMAL, "  Handler type................: %s\n",
            (this->getType() == eHT_Receive ? "Receive" : "Transmit"));
    debugOutputShort( DEBUG_LEVEL_NORMAL, "  Port, Channel...............: %2d, %2d\n",
            m_manager.get1394Service().getPort(), channel);
    debugOutputShort( DEBUG_LEVEL_NORMAL, "  Buffer, MaxPacketSize, IRQ..: %4d, %4d, %4d\n",
            m_buf_packets, m_max_packet_size, m_irq_interval);
    if (this->getType() == eHT_Transmit) {
        debugOutputShort( DEBUG_LEVEL_NORMAL, "  Speed, PreBuffers...........: %2d, %2d\n",
                                            m_speed, m_prebuffers);
    }
    debugOutputShort( DEBUG_LEVEL_NORMAL, "  Packet count................: %10d (%5d dropped)\n",
            this->getPacketCount(), this->getDroppedCount());
}

void IsoHandler::setVerboseLevel(int l)
{
    setDebugLevel(l);
    if(m_Thread) m_Thread->setVerboseLevel(l);
}

bool IsoHandler::registerStream(StreamProcessor *stream)
{
    assert(stream);
    debugOutput( DEBUG_LEVEL_VERBOSE, "registering stream (%p)\n", stream);

    if (m_Client) {
            debugFatal( "Generic IsoHandlers can have only one client\n");
            return false;
    }
    m_Client=stream;
    return true;
}

bool IsoHandler::unregisterStream(StreamProcessor *stream)
{
    assert(stream);
    debugOutput( DEBUG_LEVEL_VERBOSE, "unregistering stream (%p)\n", stream);

    if(stream != m_Client) {
            debugFatal( "no client registered\n");
            return false;
    }
    m_Client=0;
    return true;
}

void IsoHandler::flush()
{
    if(m_type == eHT_Receive) {
        raw1394_iso_recv_flush(m_handle);
    } else {
        // do nothing
    }
}

// ISO packet interface
enum raw1394_iso_disposition IsoHandler::putPacket(
                    unsigned char *data, unsigned int length,
                    unsigned char channel, unsigned char tag, unsigned char sy,
                    unsigned int cycle, unsigned int dropped) {

    debugOutput( DEBUG_LEVEL_VERY_VERBOSE,
                 "received packet: length=%d, channel=%d, cycle=%d\n",
                 length, channel, cycle );
    m_packetcount++;
    m_dropped += dropped;

    if(m_Client) {
        return m_Client->putPacket(data, length, channel, tag, sy, cycle, dropped);
    }

    return RAW1394_ISO_OK;
}


enum raw1394_iso_disposition IsoHandler::getPacket(
                    unsigned char *data, unsigned int *length,
                    unsigned char *tag, unsigned char *sy,
                    int cycle, unsigned int dropped) {

    debugOutput( DEBUG_LEVEL_VERY_VERBOSE,
                    "sending packet: length=%d, cycle=%d\n",
                    *length, cycle );
    m_packetcount++;
    m_dropped += dropped;

    if(m_Client) {
        return m_Client->getPacket(data, length, tag, sy, cycle, dropped, m_max_packet_size);
    }
    return RAW1394_ISO_OK;
}

bool IsoHandler::prepare()
{
    // check the state
    if(m_State != E_Initialized) {
        debugError("Incorrect state, expected E_Initialized, got %d\n",(int)m_State);
        return false;
    }

    // Don't call until libraw1394's raw1394_new_handle() function has been
    // fixed to correctly initialise the iso_packet_infos field.  Bug is
    // confirmed present in libraw1394 1.2.1.
    //     raw1394_iso_shutdown(m_handle);
    m_State = E_Prepared;

    debugOutput( DEBUG_LEVEL_VERBOSE, "Preparing iso handler (%p, client=%p)\n", this, m_Client);
    dumpInfo();
    if (getType() == eHT_Receive) {
        if(m_irq_interval > 1) {
            if(raw1394_iso_recv_init(m_handle,
                                    iso_receive_handler,
                                    m_buf_packets,
                                    m_max_packet_size,
                                    m_Client->getChannel(),
                                    RAW1394_DMA_BUFFERFILL,
                                    m_irq_interval)) {
                debugFatal("Could not do receive initialisation (DMA_BUFFERFILL)!\n" );
                debugFatal("  %s\n",strerror(errno));
                return false;
            }
        } else {
            if(raw1394_iso_recv_init(m_handle,
                                    iso_receive_handler,
                                    m_buf_packets,
                                    m_max_packet_size,
                                    m_Client->getChannel(),
                                    RAW1394_DMA_PACKET_PER_BUFFER,
                                    m_irq_interval)) {
                debugFatal("Could not do receive initialisation (PACKET_PER_BUFFER)!\n" );
                debugFatal("  %s\n",strerror(errno));
                return false;
            }
        }
        return true;
    } else {
        if(raw1394_iso_xmit_init(m_handle,
                                iso_transmit_handler,
                                m_buf_packets,
                                m_max_packet_size,
                                m_Client->getChannel(),
                                m_speed,
                                m_irq_interval)) {
            debugFatal("Could not do xmit initialisation!\n" );
            return false;
        }
        return true;
    }
}

bool IsoHandler::enable(int cycle)
{
    debugOutput( DEBUG_LEVEL_VERBOSE, "start on cycle %d\n", cycle);
    // check the state
    if(m_State != E_Prepared) {
        if(!prepare()) {
            debugFatal("Could not prepare handler\n");
            return false;
        }
    }

    if (getType() == eHT_Receive) {
        if(raw1394_iso_recv_start(m_handle, cycle, -1, 0)) {
            debugFatal("Could not start receive handler (%s)\n",strerror(errno));
            dumpInfo();
            return false;
        }
    } else {
        if(raw1394_iso_xmit_start(m_handle, cycle, m_prebuffers)) {
            debugFatal("Could not start xmit handler (%s)\n",strerror(errno));
            dumpInfo();
            return false;
        }
    }

    m_poll_fd.events = POLLIN;
    m_State = E_Running;
    return true;
}