/* -*- c++ -*- */
/*
 * Copyright 2011,2013 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * GNU Radio 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, or (at your option)
 * any later version.
 *
 * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include "transcendental_impl.h"
#include <gnuradio/io_signature.h>
#include <cmath>   //real math
#include <complex> //complex math
#include <map>
#include <stdexcept>

namespace gr {
namespace blocks {

/***********************************************************************
 * work function creation and registration
 **********************************************************************/
struct map_val_type {
    work_fcn_type work_fcn;
    size_t io_size;
};
typedef std::map<std::string, map_val_type> map_type;

// construct map on first use idiom
static map_type& get_map(void)
{
    static map_type map;
    return map;
}

// static initialization of this object registers a function
struct transcendental_registrant {
    transcendental_registrant(const std::string& key,
                              const work_fcn_type& work_fcn,
                              const size_t io_size)
    {
        map_val_type val;
        val.work_fcn = work_fcn;
        val.io_size = io_size;
        get_map()[key] = val;
    }
};

// macro to create a work function and register it
#define REGISTER_FUNCTION(__fcn__, __type__, __key__)                 \
    static int __key__##_work(int noutput_items,                      \
                              gr_vector_const_void_star& input_items, \
                              gr_vector_void_star& output_items)      \
    {                                                                 \
        const __type__* in = (const __type__*)input_items[0];         \
        __type__* out = (__type__*)output_items[0];                   \
        for (size_t i = 0; i < size_t(noutput_items); i++) {          \
            out[i] = std::__fcn__(in[i]);                             \
        }                                                             \
        return noutput_items;                                         \
    }                                                                 \
    transcendental_registrant __key__##_registrant(                   \
        #__key__, &__key__##_work, sizeof(__type__));

// register work functions for real types
#define REGISTER_REAL_FUNCTIONS(__fcn__)               \
    REGISTER_FUNCTION(__fcn__, float, __fcn__##_float) \
    REGISTER_FUNCTION(__fcn__, double, __fcn__##_double)

// register work functions for complex types
#define REGISTER_COMPLEX_FUNCTIONS(__fcn__)                                  \
    REGISTER_FUNCTION(__fcn__, std::complex<float>, __fcn__##_complex_float) \
    REGISTER_FUNCTION(__fcn__, std::complex<double>, __fcn__##_complex_double)

// register both complex and real
#define REGISTER_FUNCTIONS(__fcn__)  \
    REGISTER_REAL_FUNCTIONS(__fcn__) \
    REGISTER_COMPLEX_FUNCTIONS(__fcn__)

// create and register transcendental work functions
REGISTER_FUNCTIONS(cos)
REGISTER_FUNCTIONS(sin)
REGISTER_FUNCTIONS(tan)
REGISTER_REAL_FUNCTIONS(acos)
REGISTER_REAL_FUNCTIONS(asin)
REGISTER_REAL_FUNCTIONS(atan)
REGISTER_FUNCTIONS(cosh)
REGISTER_FUNCTIONS(sinh)
REGISTER_FUNCTIONS(tanh)
REGISTER_FUNCTIONS(exp)
REGISTER_FUNCTIONS(log)
REGISTER_FUNCTIONS(log10)
REGISTER_FUNCTIONS(sqrt)


transcendental::sptr transcendental::make(const std::string& name,
                                          const std::string& type)
{
    // search for an entry in the map
    const std::string key = name + "_" + type;
    const bool has_key = get_map().count(key) != 0;
    if (!has_key)
        throw std::runtime_error("could not find transcendental function for " + key);

    // make a new block with found work function
    return gnuradio::get_initial_sptr(
        new transcendental_impl(get_map()[key].work_fcn, get_map()[key].io_size));
}

transcendental_impl::transcendental_impl(const work_fcn_type& work_fcn,
                                         const size_t io_size)
    : sync_block("transcendental",
                 io_signature::make(1, 1, io_size),
                 io_signature::make(1, 1, io_size)),
      _work_fcn(work_fcn)
{
    // NOP
}

transcendental_impl::~transcendental_impl() {}

int transcendental_impl::work(int noutput_items,
                              gr_vector_const_void_star& input_items,
                              gr_vector_void_star& output_items)
{
    return _work_fcn(noutput_items, input_items, output_items);
}

} /* namespace blocks */
} /* namespace gr */
