/* -*- c++ -*- */
/*
 * Copyright 2006,2012 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.
 */

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

#include <gr_basic_block.h>
#include <gr_block_registry.h>
#include <stdexcept>
#include <sstream>
#include <iostream>

static long s_next_id = 0;
static long s_ncurrently_allocated = 0;

long
gr_basic_block_ncurrently_allocated()
{
  return s_ncurrently_allocated;
}

gr_basic_block::gr_basic_block(const std::string &name,
                               gr_io_signature_sptr input_signature,
                               gr_io_signature_sptr output_signature)
  : d_name(name),
    d_input_signature(input_signature),
    d_output_signature(output_signature),
    d_unique_id(s_next_id++),
    d_symbolic_id(global_block_registry.block_register(this)),
    d_symbol_name(global_block_registry.register_symbolic_name(this)),
    d_color(WHITE),
    d_rpc_set(false),
    message_subscribers(pmt::make_dict())
{
  s_ncurrently_allocated++;
}

gr_basic_block::~gr_basic_block()
{
  s_ncurrently_allocated--;
  global_block_registry.block_unregister(this);
}

gr_basic_block_sptr
gr_basic_block::to_basic_block()
{
  return shared_from_this();
}

void
gr_basic_block::set_block_alias(std::string name)
{ 
  global_block_registry.register_symbolic_name(this, name); 
}

// ** Message passing interface **

//  - register a new input message port
void
gr_basic_block::message_port_register_in(pmt::pmt_t port_id)
{
  if(!pmt::is_symbol(port_id)) {
    throw std::runtime_error("message_port_register_in: bad port id");
  }
  msg_queue[port_id] = msg_queue_t();
  msg_queue_ready[port_id] = boost::shared_ptr<boost::condition_variable>(new boost::condition_variable());
}

pmt::pmt_t
gr_basic_block::message_ports_in()
{
  pmt::pmt_t port_names = pmt::make_vector(msg_queue.size(), pmt::PMT_NIL);
  msg_queue_map_itr itr = msg_queue.begin();
  for(size_t i = 0; i < msg_queue.size(); i++) {
    pmt::vector_set(port_names, i, (*itr).first);
    itr++;
  }
  return port_names;
}

//  - register a new output message port
void
gr_basic_block::message_port_register_out(pmt::pmt_t port_id)
{
  if(!pmt::is_symbol(port_id)) {
    throw std::runtime_error("message_port_register_out: bad port id");
  }
  if(pmt::dict_has_key(message_subscribers, port_id)) {
    throw std::runtime_error("message_port_register_out: port already in use");
  }
  message_subscribers = pmt::dict_add(message_subscribers, port_id, pmt::PMT_NIL);
}

pmt::pmt_t
gr_basic_block::message_ports_out()
{
  size_t len = pmt::length(message_subscribers);
  pmt::pmt_t port_names = pmt::make_vector(len, pmt::PMT_NIL);
  pmt::pmt_t keys = pmt::dict_keys(message_subscribers);
  for(size_t i = 0; i < len; i++) {
    pmt::vector_set(port_names, i, pmt::nth(i, keys));
  }
  return port_names;
}

//  - publish a message on a message port
void gr_basic_block::message_port_pub(pmt::pmt_t port_id, pmt::pmt_t msg)
{
  if(!pmt::dict_has_key(message_subscribers, port_id)) {
    throw std::runtime_error("port does not exist");
  }
  
  pmt::pmt_t currlist = pmt::dict_ref(message_subscribers, port_id, pmt::PMT_NIL);
  // iterate through subscribers on port
  while(pmt::is_pair(currlist)) {
    pmt::pmt_t target = pmt::car(currlist);

    pmt::pmt_t block = pmt::car(target);
    pmt::pmt_t port = pmt::cdr(target);
    
    currlist = pmt::cdr(currlist);
    gr_basic_block_sptr blk = global_block_registry.block_lookup(block);
    //blk->post(msg);
    blk->post(port, msg);
  }
}

//  - subscribe to a message port
void
gr_basic_block::message_port_sub(pmt::pmt_t port_id, pmt::pmt_t target){
  if(!pmt::dict_has_key(message_subscribers, port_id)){ 
    std::stringstream ss;
    ss << "Port does not exist: \"" << pmt::write_string(port_id) << "\" on block: " << pmt::write_string(target) << std::endl;
    throw std::runtime_error(ss.str());
  }
  pmt::pmt_t currlist = pmt::dict_ref(message_subscribers,port_id,pmt::PMT_NIL);
  
  // ignore re-adds of the same target
  if(!pmt::list_has(currlist, target))
    message_subscribers = pmt::dict_add(message_subscribers,port_id,pmt::list_add(currlist,target));
}

void
gr_basic_block::message_port_unsub(pmt::pmt_t port_id, pmt::pmt_t target){
  if(!pmt::dict_has_key(message_subscribers, port_id)){ 
    std::stringstream ss;
    ss << "Port does not exist: \"" << pmt::write_string(port_id) << "\" on block: " << pmt::write_string(target) << std::endl;
    throw std::runtime_error(ss.str());
  }
  
  // ignore unsubs of unknown targets
  pmt::pmt_t currlist = pmt::dict_ref(message_subscribers,port_id,pmt::PMT_NIL);
  message_subscribers = pmt::dict_add(message_subscribers,port_id,pmt::list_rm(currlist,target));
}

void
gr_basic_block::_post(pmt::pmt_t which_port, pmt::pmt_t msg)
{
  insert_tail(which_port, msg);
}

void
gr_basic_block::insert_tail(pmt::pmt_t which_port, pmt::pmt_t msg)
{
  gr::thread::scoped_lock guard(mutex);

    if( (msg_queue.find(which_port) == msg_queue.end()) || (msg_queue_ready.find(which_port) == msg_queue_ready.end())){
        std::cout << "target port = " << pmt::symbol_to_string(which_port) << std::endl;
        throw std::runtime_error("attempted to insert_tail on invalid queue!");
    }

  msg_queue[which_port].push_back(msg);
  msg_queue_ready[which_port]->notify_one();

  // wake up thread if BLKD_IN or BLKD_OUT
  global_block_registry.notify_blk(alias());
}

pmt::pmt_t
gr_basic_block::delete_head_nowait(pmt::pmt_t which_port)
{
  gr::thread::scoped_lock guard(mutex);

  if (empty_p(which_port)){
    return pmt::pmt_t();
    }

  pmt::pmt_t m(msg_queue[which_port].front());
  msg_queue[which_port].pop_front();

  return m;
}

pmt::pmt_t
gr_basic_block::delete_head_blocking(pmt::pmt_t which_port)
{
  gr::thread::scoped_lock guard(mutex);

  while (empty_p(which_port)){
    msg_queue_ready[which_port]->wait(guard);
    }

  pmt::pmt_t m(msg_queue[which_port].front());
  msg_queue[which_port].pop_front();
  return m;
}