/*
* Copyright 2008, 2009, 2010 Free Software Foundation, Inc.
* Copyright 2010 Kestrel Signal Processing, Inc.
*
* This software is distributed under the terms of the GNU Affero Public License.
* See the COPYING file in the main directory for details.
*
* This use of this software may be subject to additional restrictions.
* See the LEGAL file in the main directory for details.

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero 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 Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.

*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "Transceiver.h"
#include "radioDevice.h"

#include <time.h>
#include <signal.h>

#include <GSMCommon.h>
#include <Logger.h>
#include <Configuration.h>

#define CONFIGDB            "/etc/OpenBTS/OpenBTS.db"

/* Samples-per-symbol for downlink path
 *     4 - Uses precision modulator (more computation, less distortion)
 *     1 - Uses minimized modulator (less computation, more distortion)
 *
 *     Other values are invalid. Receive path (uplink) is always
 *     downsampled to 1 sps. Default to 4 sps for all cases except for
 *     ARM and non-SIMD enabled architectures.
 */
#if defined(HAVE_NEON) || !defined(HAVE_SSE3)
#define SPS		1
#else
#define SPS		4
#endif

ConfigurationTable gConfig(CONFIGDB);

volatile bool gbShutdown = false;

static void ctrlCHandler(int signo)
{
  std::cout << "Received shutdown signal" << std::endl;
  gbShutdown = true;
}

/*
 * Attempt to open and test the database file before
 * accessing the configuration table. We do this because
 * the global table constructor cannot provide notification
 * in the event of failure.
 */
int testConfig(const char *filename)
{
  int rc, val = 9999;
  sqlite3 *db;
  std::string test = "sadf732zdvj2";

  const char *keys[3] = {
    "Log.Level",
    "TRX.Port",
    "TRX.IP",
  };

  /* Try to open the database  */
  rc = sqlite3_open(filename, &db);
  if (rc || !db) {
    std::cerr << "Config: Database could not be opened" << std::endl;
    return -1;
  } else {
    sqlite3_close(db);
  }

  /* Attempt to set a value in the global config */
  if (!gConfig.set(test, val)) {
    std::cerr << "Config: Failed to set test key - "
              << "permission to access the database?" << std::endl;
    return -1;
  } else {
    gConfig.remove(test);
  }

  /* Attempt to query */
  for (int i = 0; i < 3; i++) {
    try {
      gConfig.getStr(keys[i]); 
    } catch (...) {
      std::cerr << "Config: Failed query on " << keys[i] << std::endl;
      return -1;
    }
  }

  return 0; 
}

int main(int argc, char *argv[])
{
  int trxPort, radioType, chans = 1, extref = 0, fail = 0;
  std::string logLevel, trxAddr, deviceArgs = "";
  RadioDevice *usrp = NULL;
  RadioInterface *radio = NULL;
  Transceiver *trx = NULL;
  VectorFIFO *fifo = NULL;

  if (argc == 3) {
    deviceArgs = std::string(argv[2]);
    chans = atoi(argv[1]);
  } else if (argc == 2) {
    chans = atoi(argv[1]);
  } else if (argc != 1) {
    std::cout << argv[0] << " <number of channels> <device args>" << std::endl;
  }

  if (signal(SIGINT, ctrlCHandler) == SIG_ERR) {
    std::cerr << "Couldn't install signal handler for SIGINT" << std::endl;
    return EXIT_FAILURE;
  }

  if (signal(SIGTERM, ctrlCHandler) == SIG_ERR)  {
    std::cerr << "Couldn't install signal handler for SIGTERM" << std::endl;
    return EXIT_FAILURE;
  }

  // Configure logger.
  if (testConfig(CONFIGDB) < 0) {
    std::cerr << "Config: Database failure" << std::endl;
    return EXIT_FAILURE;
  }

  logLevel = gConfig.getStr("Log.Level");
  trxPort = gConfig.getNum("TRX.Port");
  trxAddr = gConfig.getStr("TRX.IP");

  if (gConfig.defines("TRX.Reference"))
    extref = gConfig.getNum("TRX.Reference");

  if (extref)
    std::cout << "Using external clock reference" << std::endl;
  else
    std::cout << "Using internal clock reference" << std::endl;

  gLogInit("transceiver", logLevel.c_str(), LOG_LOCAL7);

  srandom(time(NULL));

  usrp = RadioDevice::make(SPS, chans);
  radioType = usrp->open(deviceArgs, extref);
  if (radioType < 0) {
    LOG(ALERT) << "Transceiver exiting..." << std::endl;
    return EXIT_FAILURE;
  }

  switch (radioType) {
  case RadioDevice::NORMAL:
    radio = new RadioInterface(usrp, 3, SPS, chans);
    break;
  case RadioDevice::RESAMP_64M:
  case RadioDevice::RESAMP_100M:
    radio = new RadioInterfaceResamp(usrp, 3, SPS, chans);
    break;
  default:
    LOG(ALERT) << "Unsupported configuration";
    fail = 1;
    goto shutdown;
  }
  if (!radio->init(radioType)) {
    LOG(ALERT) << "Failed to initialize radio interface";
    fail = 1;
    goto shutdown;
  }

  trx = new Transceiver(trxPort, trxAddr.c_str(),
                        SPS, chans, GSM::Time(3,0), radio);
  if (!trx->init()) {
    LOG(ALERT) << "Failed to initialize transceiver";
    fail = 1;
    goto shutdown;
  }

  for (int i = 0; i < chans; i++) {
    fifo = radio->receiveFIFO(i);
    if (fifo && trx->receiveFIFO(fifo, i))
      continue;

    LOG(ALERT) << "Could not attach FIFO to channel " << i;
    fail = 1;
    goto shutdown;
  }

  trx->start();

  while (!gbShutdown)
    sleep(1);

shutdown:
  std::cout << "Shutting down transceiver..." << std::endl;

  delete trx;
  delete radio;
  delete usrp;

  if (fail)
    return EXIT_FAILURE;

  return 0;
}