/* -*- c++ -*- */
/*
 * gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
 *
 *  Copyright (C) 2016, 2017
 *  Libre Space Foundation <http://librespacefoundation.org/>
 *
 *  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/>.
 */

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

#include <gnuradio/io_signature.h>
#include "morse_decoder_impl.h"
#include <satnogs/log.h>
namespace gr
{
namespace satnogs
{

morse_decoder::sptr
morse_decoder::make (char unrecognized_char, size_t min_frame_len)
{
  return gnuradio::get_initial_sptr (
      new morse_decoder_impl (unrecognized_char, min_frame_len));
}

void
morse_decoder_impl::symbol_msg_handler (pmt::pmt_t msg)
{
  bool res = false;
  morse_symbol_t s;
  s = (morse_symbol_t) pmt::to_long (msg);

  switch (s)
    {
    case MORSE_DOT:
    case MORSE_DASH:
    case MORSE_S_SPACE:
      res = d_morse_tree.received_symbol (s);
      break;
      /*
       * If a word separator occurs it is a good time to retrieve the decoded
       * word
       */
    case MORSE_L_SPACE:
      /*
       * Inject a character separator, for the morse decoder to commit
       * the outstanding character
       */
      res = d_morse_tree.received_symbol (MORSE_S_SPACE);
      /* Just ignore the word separator if no word is yet decoded */
      if (d_morse_tree.get_word_len () == 0) {
        res = true;
        break;
      }
      d_str = d_str.append(d_morse_tree.get_word ());
      d_str = d_str.append(" ");
      d_morse_tree.reset ();
      break;
    case MORSE_INTRA_SPACE:
      /*Ignore it */
      break;
    case MORSE_END_MSG_SPACE:
      if (d_str.length () > d_min_frame_len) {
        d_morse_tree.reset ();
        message_port_pub (pmt::mp ("out"),
                          pmt::make_blob (d_str.c_str (), d_str.length ()));
        d_str = "";
      }
      break;
    default:
      LOG_ERROR("Unknown Morse symbol");
      return;
    }

  /*
   * If the decoding return false, it means that either an non decode-able
   * character situation occurred or the maximum word limit reached
   */
  if (!res) {
    if (d_morse_tree.get_max_word_len () == d_morse_tree.get_word_len ()) {
      d_str = d_morse_tree.get_word ();
      d_morse_tree.reset ();
      message_port_pub (pmt::mp ("out"),
                        pmt::make_blob (d_str.c_str (), d_str.length ()));
    }
  }
}

/*
 * The private constructor
 */
morse_decoder_impl::morse_decoder_impl (char unrecognized_char,
                                        size_t min_frame_len) :
        gr::block ("morse_decoder", gr::io_signature::make (0, 0, 0),
                   gr::io_signature::make (0, 0, 0)),
        d_morse_tree (unrecognized_char),
        d_min_frame_len (min_frame_len),
        d_str("")

{
  /* Register the input and output msg handler */
  message_port_register_in (pmt::mp ("in"));
  message_port_register_out (pmt::mp ("out"));
  set_msg_handler (
      pmt::mp ("in"),
      boost::bind (&morse_decoder_impl::symbol_msg_handler, this, _1));
}

} /* namespace satnogs */
} /* namespace gr */