/*Copyright 2014 Francisco Alvaro

This file is part of SESHAT.

  SESHAT 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.

  SESHAT 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 SESHAT.  If not, see <http://www.gnu.org/licenses/>.


This file is a modification of the RNNLIB original software covered by
the following copyright and permission notice:

*/
/*Copyright 2009,2010 Alex Graves

  This file is part of RNNLIB.

  RNNLIB 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.

  RNNLIB 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 RNNLIB.  If not, see <http://www.gnu.org/licenses/>.*/

#ifndef _INCLUDED_WeightContainer_h  
#define _INCLUDED_WeightContainer_h  

#include <vector>
#include <numeric>
#include <algorithm>
#include <functional>
#include <math.h>
#include <boost/tuple/tuple.hpp>
#include "Random.hpp"
#include "DataExporter.hpp"

using namespace std;

typedef multimap<string, tuple<string, string, int, int> >::iterator WC_CONN_IT; 
typedef pair<string, tuple<string, string, int, int> > WC_CONN_PAIR;

struct WeightContainer: public DataExporter
{
  //data
  Vector<real_t> weights;
  Vector<real_t> derivatives;
  multimap<string, tuple<string, string, int, int> > connections;
	
  //functions
  WeightContainer(DataExportHandler *deh):
    DataExporter("weightContainer", deh)
  {
  }

  void link_layers(const string& fromName, const string& toName, const string& connName = "", int paramBegin = 0, int paramEnd = 0) {
    connections.insert(make_pair(toName, make_tuple(fromName, connName, paramBegin, paramEnd)));
  }
  
  pair<size_t, size_t> new_parameters(size_t numParams, const string& fromName, const string& toName, const string& connName) {
    size_t begin = weights.size();
    weights.resize(weights.size() + numParams);
    size_t end = weights.size();
    link_layers(fromName, toName, connName, begin, end);
    return make_pair(begin, end);
  }

  View<real_t> get_weights(pair<int, int> range)
  {
    return weights.slice(range);
  }

  View<real_t> get_derivs(pair<int, int> range)
  {
    return derivatives.slice(range);
  }

  int randomise(real_t range)
  {
    int numRandWts = 0;
    LOOP(real_t& w, weights)
      {
	if (w == infinity)
	  {
	    w = Random::uniform(range);
	    ++numRandWts;
	  }
      }
    return numRandWts;
  }

  void reset_derivs()
  {
    fill(derivatives, 0);
  }

  void save_by_conns(vector<real_t>& container, const string& nam)
  {
    LOOP(const WC_CONN_PAIR& p, connections)
      {
	VDI begin = container.begin() + p.second.get<2>();
	VDI end = container.begin() + p.second.get<3>();
	if (begin != end)
	  {
	    save_range(make_pair(begin, end), p.second.get<1>() + "_" + nam);
	  }
      }
  }

  //MUST BE CALLED BEFORE WEIGHT CONTAINER IS USED
  void build()
  {
    fill(weights, infinity);
    derivatives.resize(weights.size());
    save_by_conns(weights, "weights");
    reset_derivs();
  }
};

void perturb_weight(real_t& weight, real_t stdDev, bool additive = true);
template <class R> void perturb_weights(R& weights, real_t stdDev, bool additive = true);
template <class R> void perturb_weights(R& weights, R& stdDevs, bool additive = true);

#endif