/* -*- 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 */