/*
 * cDemux implementation for generic dvbapi
 *
 * derived from libtriple/dmx_td.cpp
 *
 * (C) 2010-2013 Stefan Seyfried
 *
 * 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 2 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 "config.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <poll.h>
#include <errno.h>
#include <inttypes.h>

#include <cstring>
#include <cstdio>
#include <string>
#include <unistd.h>
#include <sys/ioctl.h>
#include "dmx_hal.h"
#include "hal_debug.h"

#include "video_lib.h"
/* needed for getSTC... */
extern cVideo *videoDecoder;

#define hal_debug(args...) _hal_debug(HAL_DEBUG_DEMUX, this, args)
#define hal_info(args...) _hal_info(HAL_DEBUG_DEMUX, this, args)
#define hal_info_c(args...) _hal_info(HAL_DEBUG_DEMUX, NULL, args)

#define dmx_err(_errfmt, _errstr, _revents) do { \
		hal_info("%s " _errfmt " fd:%d, ev:0x%x %s pid:0x%04hx flt:0x%02hx\n", \
		    __func__, _errstr, fd, _revents, DMX_T[dmx_type], pid, flt); \
	} while(0);

cDemux *videoDemux = NULL;
cDemux *audioDemux = NULL;
//cDemux *pcrDemux = NULL;

static const char *DMX_T[] =
{
	"DMX_INVALID",
	"DMX_VIDEO",
	"DMX_AUDIO",
	"DMX_PES",
	"DMX_PSI",
	"DMX_PIP",
	"DMX_TP",
	"DMX_PCR"
};

/* map the device numbers. for now only demux0 is used */
static const char *devname[] =
{
	"/dev/dvb/adapter0/demux0",
	"/dev/dvb/adapter0/demux0",
	"/dev/dvb/adapter0/demux0"
};

/* uuuugly */
static int dmx_tp_count = 0;
#define MAX_TS_COUNT 8

extern bool HAL_nodec;

cDemux::cDemux(int n)
{
	if (n < 0 || n > 2)
	{
		hal_info("%s ERROR: n invalid (%d)\n", __FUNCTION__, n);
		num = 0;
	}
	else
		num = n;
	fd = -1;
}

cDemux::~cDemux()
{
	hal_debug("%s #%d fd: %d\n", __FUNCTION__, num, fd);
	Close();
}

bool cDemux::Open(DMX_CHANNEL_TYPE pes_type, void * /*hVideoBuffer*/, int uBufferSize)
{
	int devnum = num;
	int flags = O_RDWR | O_CLOEXEC;
	if (fd > -1)
		hal_info("%s FD ALREADY OPENED? fd = %d\n", __FUNCTION__, fd);

	dmx_type = pes_type;
	if (pes_type != DMX_PSI_CHANNEL)
		flags |= O_NONBLOCK;

	fd = open(devname[devnum], flags);
	if (fd < 0)
	{
		hal_info("%s %s: %m\n", __FUNCTION__, devname[devnum]);
		return false;
	}
	hal_debug("%s #%d pes_type: %s(%d), uBufferSize: %d fd: %d\n", __func__,
	    num, DMX_T[pes_type], pes_type, uBufferSize, fd);

	if (dmx_type == DMX_VIDEO_CHANNEL)
		uBufferSize = 0x100000;     /* 1MB */
	if (dmx_type == DMX_AUDIO_CHANNEL)
		uBufferSize = 0x10000;      /* 64k */
#if 0
	if (!pesfds.empty())
	{
		hal_info("%s ERROR! pesfds not empty!\n", __FUNCTION__); /* TODO: error handling */
		return false;
	}
	int n = DMX_SOURCE_FRONT0;
	if (ioctl(fd, DMX_SET_SOURCE, &n) < 0)
		hal_info("%s DMX_SET_SOURCE %d failed! (%m)\n", __func__, n);
#endif
	if (uBufferSize > 0)
	{
		/* probably uBufferSize == 0 means "use default size". TODO: find a reasonable default */
		if (ioctl(fd, DMX_SET_BUFFER_SIZE, uBufferSize) < 0)
			hal_info("%s DMX_SET_BUFFER_SIZE failed (%m)\n", __func__);
	}
	buffersize = uBufferSize;

	return true;
}

void cDemux::Close(void)
{
	hal_debug("%s #%d, fd = %d\n", __FUNCTION__, num, fd);
	if (fd < 0)
	{
		hal_info("%s #%d: not open!\n", __FUNCTION__, num);
		return;
	}
	pesfds.clear();
	ioctl(fd, DMX_STOP);
	close(fd);
	fd = -1;
	if (dmx_type == DMX_TP_CHANNEL)
	{
		dmx_tp_count--;
		if (dmx_tp_count < 0)
		{
			hal_info("%s dmx_tp_count < 0!!\n", __func__);
			dmx_tp_count = 0;
		}
	}
}

bool cDemux::Start(bool)
{
	hal_debug("%s #%d fd: %d type: %s\n", __func__, num, fd, DMX_T[dmx_type]);
	if (fd < 0)
	{
		hal_info("%s #%d: not open!\n", __FUNCTION__, num);
		return false;
	}
	ioctl(fd, DMX_START);
	return true;
}

bool cDemux::Stop(void)
{
	hal_debug("%s #%d fd: %d type: %s\n", __func__, num, fd, DMX_T[dmx_type]);
	if (fd < 0)
	{
		hal_info("%s #%d: not open!\n", __FUNCTION__, num);
		return false;
	}
	ioctl(fd, DMX_STOP);
	return true;
}

int cDemux::Read(unsigned char *buff, int len, int timeout)
{
#if 0
	if (len != 4095 && timeout != 100)
		fprintf(stderr, "cDemux::%s #%d fd: %d type: %s len: %d timeout: %d\n",
		    __FUNCTION__, num, fd, DMX_T[dmx_type], len, timeout);
#endif
	int rc;
	struct pollfd ufds;
	ufds.fd = fd;
	ufds.events = POLLIN | POLLPRI | POLLERR;
	ufds.revents = 0;

	/* hack: if the frontend loses and regains lock, the demuxer often will not
	 * return from read(), so as a "emergency exit" for e.g. NIT scan, set a (long)
	 * timeout here */
	int to = timeout;
	if (dmx_type == DMX_PSI_CHANNEL && timeout <= 0){
		to = 60 * 1000;
	}

	if (to > 0)
	{
retry:
		rc = ::poll(&ufds, 1, to);
		if (!rc)
			return 0; // timeout
		else if (rc < 0)
		{
			dmx_err("poll: %s,", strerror(errno), 0)
			//hal_info("%s poll: %m\n", __FUNCTION__);
			/* happens, when running under gdb... */
			if (errno == EINTR)
				goto retry;
			return -1;
		}
#if 0
		if (ufds.revents & POLLERR) /* POLLERR means buffer error, i.e. buffer overflow */
		{
			dmx_err("received %s,", "POLLERR", ufds.revents);
			/* this seems to happen sometimes at recording start, without bad effects */
			return 0;
		}
#endif
		if (ufds.revents & POLLHUP) /* we get POLLHUP if e.g. a too big DMX_BUFFER_SIZE was set */
		{
			dmx_err("received %s,", "POLLHUP", ufds.revents);
			return -1;
		}
		if (!(ufds.revents & POLLIN)) /* we requested POLLIN but did not get it? */
		{
			dmx_err("received %s, please report!", "POLLIN", ufds.revents);
			return 0;
		}
	}

	rc = ::read(fd, buff, len);
	//fprintf(stderr, "fd %d ret: %d\n", fd, rc);
	if (rc < 0)
		dmx_err("read: %s", strerror(errno), 0);

	return rc;
}

bool cDemux::sectionFilter(unsigned short _pid, const unsigned char *const filter,
    const unsigned char *const mask, int len, int timeout,
    const unsigned char *const negmask)
{
	struct dmx_sct_filter_params s_flt;
	memset(&s_flt, 0, sizeof(s_flt));
	pid = _pid;

	if (len > DMX_FILTER_SIZE)
	{
		hal_info("%s #%d: len too long: %d, DMX_FILTER_SIZE %d\n", __func__, num, len, DMX_FILTER_SIZE);
		len = DMX_FILTER_SIZE;
	}
	s_flt.pid = pid;
	s_flt.timeout = timeout;
	flt = filter[0];
	memcpy(s_flt.filter.filter, filter, len);
	memcpy(s_flt.filter.mask,   mask,   len);
	if (negmask != NULL)
		memcpy(s_flt.filter.mode, negmask, len);

	s_flt.flags = DMX_IMMEDIATE_START | DMX_CHECK_CRC;

	int to = 0;
	switch (filter[0])
	{
		case 0x00: /* program_association_section */
			to = 2000;
			break;
		case 0x01: /* conditional_access_section */
			to = 6000;
			break;
		case 0x02: /* program_map_section */
			to = 1500;
			break;
		case 0x03: /* transport_stream_description_section */
			to = 10000;
			break;
		/* 0x04 - 0x3F: reserved */
		case 0x40: /* network_information_section - actual_network */
			to = 10000;
			break;
		case 0x41: /* network_information_section - other_network */
			to = 15000;
			break;
		case 0x42: /* service_description_section - actual_transport_stream */
			to = 10000;
			break;
		/* 0x43 - 0x45: reserved for future use */
		case 0x46: /* service_description_section - other_transport_stream */
			to = 10000;
			break;
		/* 0x47 - 0x49: reserved for future use */
		case 0x4A: /* bouquet_association_section */
			to = 11000;
			break;
		/* 0x4B - 0x4D: reserved for future use */
		case 0x4E: /* event_information_section - actual_transport_stream, present/following */
			to = 2000;
			break;
		case 0x4F: /* event_information_section - other_transport_stream, present/following */
			to = 10000;
			break;
		/* 0x50 - 0x5F: event_information_section - actual_transport_stream, schedule */
		/* 0x60 - 0x6F: event_information_section - other_transport_stream, schedule */
		case 0x70: /* time_date_section */
			s_flt.flags &= ~DMX_CHECK_CRC; /* section has no CRC */
			//s_flt.pid     = 0x0014;
			to = 30000;
			break;
		case 0x71: /* running_status_section */
			s_flt.flags &= ~DMX_CHECK_CRC; /* section has no CRC */
			to = 0;
			break;
		case 0x72: /* stuffing_section */
			s_flt.flags &= ~DMX_CHECK_CRC; /* section has no CRC */
			to = 0;
			break;
		case 0x73: /* time_offset_section */
			//s_flt.pid     = 0x0014;
			to = 30000;
			break;
		/* 0x74 - 0x7D: reserved for future use */
		case 0x7E: /* discontinuity_information_section */
			s_flt.flags &= ~DMX_CHECK_CRC; /* section has no CRC */
			to = 0;
			break;
		case 0x7F: /* selection_information_section */
			to = 0;
			break;
		/* 0x80 - 0x8F: ca_message_section */
		/* 0x90 - 0xFE: user defined */
		/*        0xFF: reserved */
		default:
			break;
//		return -1;
	}
	/* the negmask == NULL is a hack: the users of negmask are PMT-update
	 * and sectionsd EIT-Version change. And they really want no timeout
	 * if timeout == 0 instead of "default timeout" */
	if (timeout == 0 && negmask == NULL)
		s_flt.timeout = to;

	hal_debug("%s #%d pid:0x%04hx fd:%d type:%s len:%d to:%d flags:%x flt[0]:%02x\n", __func__, num,
	    pid, fd, DMX_T[dmx_type], len, s_flt.timeout, s_flt.flags, s_flt.filter.filter[0]);

	if (debuglevel == 2)
	{
		fprintf(stderr, "filt: ");
		for (int i = 0; i < DMX_FILTER_SIZE; i++)fprintf(stderr, "%02hhx ", s_flt.filter.filter[i]);
		fprintf(stderr, "\n");
		fprintf(stderr, "mask: ");
		for (int i = 0; i < DMX_FILTER_SIZE; i++)fprintf(stderr, "%02hhx ", s_flt.filter.mask  [i]);
		fprintf(stderr, "\n");
		fprintf(stderr, "mode: ");
		for (int i = 0; i < DMX_FILTER_SIZE; i++)fprintf(stderr, "%02hhx ", s_flt.filter.mode  [i]);
		fprintf(stderr, "\n");
	}

	ioctl(fd, DMX_STOP);
	if (ioctl(fd, DMX_SET_FILTER, &s_flt) < 0)
		return false;

	return true;
}

bool cDemux::pesFilter(const unsigned short _pid)
{
	struct dmx_pes_filter_params p_flt;
	pid = _pid;
	flt = 0;
	/* allow PID 0 for web streaming e.g.
	 * this check originally is from tuxbox cvs but I'm not sure
	 * what it is good for...
	if (pid <= 0x0001 && dmx_type != DMX_PCR_ONLY_CHANNEL)
	    return false;
	 */
	if ((pid >= 0x0002 && pid <= 0x000f) || pid >= 0x1fff)
		return false;

	hal_debug("%s #%d pid: 0x%04hx fd: %d type: %s\n", __FUNCTION__, num, pid, fd, DMX_T[dmx_type]);

	memset(&p_flt, 0, sizeof(p_flt));
	p_flt.pid = pid;
	p_flt.output = DMX_OUT_DECODER;
	p_flt.input  = DMX_IN_FRONTEND;

	switch (dmx_type)
	{
		case DMX_PCR_ONLY_CHANNEL:
			p_flt.pes_type = DMX_PES_PCR;
			if (HAL_nodec)
				return true;
			break;
		case DMX_AUDIO_CHANNEL:
			p_flt.pes_type = DMX_PES_OTHER;
			p_flt.output  = DMX_OUT_TSDEMUX_TAP;
			if (HAL_nodec)  /* no need to demux if we don't decode... */
				return true;
			break;
		case DMX_VIDEO_CHANNEL:
			p_flt.pes_type = DMX_PES_OTHER;
			p_flt.output  = DMX_OUT_TSDEMUX_TAP;
			if (HAL_nodec)
				return true;
			break;
		case DMX_PES_CHANNEL:
			p_flt.pes_type = DMX_PES_OTHER;
			p_flt.output  = DMX_OUT_TAP;
			break;
		case DMX_TP_CHANNEL:
			p_flt.pes_type = DMX_PES_OTHER;
			p_flt.output  = DMX_OUT_TSDEMUX_TAP;
			break;
		default:
			hal_info("%s #%d invalid dmx_type %d!\n", __func__, num, dmx_type);
			return false;
	}
	return (ioctl(fd, DMX_SET_PES_FILTER, &p_flt) >= 0);
}

void cDemux::SetSyncMode(AVSYNC_TYPE /*mode*/)
{
	hal_debug("%s #%d\n", __FUNCTION__, num);
}

void *cDemux::getBuffer()
{
	hal_debug("%s #%d\n", __FUNCTION__, num);
	return NULL;
}

void *cDemux::getChannel()
{
	hal_debug("%s #%d\n", __FUNCTION__, num);
	return NULL;
}

bool cDemux::addPid(unsigned short Pid)
{
	hal_debug("%s: pid 0x%04hx\n", __func__, Pid);
	pes_pids pfd;
	int ret;
	if (dmx_type != DMX_TP_CHANNEL)
	{
		hal_info("%s pes_type %s not implemented yet! pid=%hx\n", __FUNCTION__, DMX_T[dmx_type], Pid);
		return false;
	}
	if (fd == -1)
		hal_info("%s bucketfd not yet opened? pid=%hx\n", __FUNCTION__, Pid);
	pfd.fd = fd; /* dummy */
	pfd.pid = Pid;
	pesfds.push_back(pfd);
	ret = (ioctl(fd, DMX_ADD_PID, &Pid));
	if (ret < 0)
		hal_info("%s: DMX_ADD_PID (%m)\n", __func__);
	return (ret != -1);
}

void cDemux::removePid(unsigned short Pid)
{
	if (dmx_type != DMX_TP_CHANNEL)
	{
		hal_info("%s pes_type %s not implemented yet! pid=%hx\n", __FUNCTION__, DMX_T[dmx_type], Pid);
		return;
	}
	for (std::vector<pes_pids>::iterator i = pesfds.begin(); i != pesfds.end(); ++i)
	{
		if ((*i).pid == Pid)
		{
			hal_debug("removePid: removing demux fd %d pid 0x%04x\n", fd, Pid);
			if (ioctl(fd, DMX_REMOVE_PID, Pid) < 0)
				hal_info("%s: (DMX_REMOVE_PID, 0x%04hx): %m\n", __func__, Pid);
			pesfds.erase(i);
			return; /* TODO: what if the same PID is there multiple times */
		}
	}
	hal_info("%s pid 0x%04x not found\n", __FUNCTION__, Pid);
}

void cDemux::getSTC(int64_t *STC)
{
	int64_t pts = 0;
	if (videoDecoder)
		pts = videoDecoder->GetPTS();
	*STC = pts;
}

int cDemux::getUnit(void)
{
	hal_debug("%s #%d\n", __FUNCTION__, num);
	/* just guessed that this is the right thing to do.
	   right now this is only used by the CA code which is stubbed out
	   anyway */
	return num;
}

bool cDemux::SetSource(int unit, int source)
{
	hal_info_c("%s(%d, %d): not implemented yet\n", __func__, unit, source);
	return true;
}

int cDemux::GetSource(int unit)
{
	hal_info_c("%s(%d): not implemented yet\n", __func__, unit);
	return 0;
}