#ifndef LAYER_H
#define LAYER_H
///////////////////////////////////////////////////////////////
//  layer.h     - layer is a container of neurons            //
//  ver 1.0                                                  //
//                                                           //
//  Language:     Visual C++, ver 6.0                        //
//  Platform:     Dell XPS B1000r, Windows 2000              //
//  Application:  Prototype for Pr#1, ELE 591/791            //
//  Author:       Jim Fawcett, CST 2-187, Syracuse Univ      //
//                (315) 443-3948, jfawcett@twcny.rr.com      //
///////////////////////////////////////////////////////////////
/*

    Module Contents
    ===============
    This module defines a layer class.  Its operations are simple.
    When a layer is constructed it is passed the address of a proto-
    typical neuron.  It uses the neuron's clone function to populate
    itself with a specified number of neurons, all of the clones type.

    The ith layer input is passed directly to the ith input of each
    neuron in the layer.  Each neuron output is a layer output.
    
    Operations
    ==========
    linearNeuron ln(3);
    layer hidden(5,&ln);      Creates a layer with 5 linear neurons
    hidden.input(1,value);    sets 2nd input of each neuron to value
    hidden.weight(2,1,value); sets 3rd weight of 2nd neuron to value
    hidden.output(2);         returns output of 3rd neuron in layer

*/

//
///////////////////////////////////////////////////////////////
//  Build Process                                            //
///////////////////////////////////////////////////////////////
//  Required Files:                                          //
//    layer.h, layer.cpp, neuron.h, neuron.cpp               //
//                                                           //
//  Compiler Command:                                        //
//    cl /GX /DTEST_LAYER layer.cpp neuron.cpp               //
///////////////////////////////////////////////////////////////
/*
    Maintenance History
    ===================
    ver 1.0 : 8 Jun 2000
    - first release
    - this is a prototype defining only linear neurons

*/

///////////////////////////////////////////////////////////////
//  layer class - container for neurons of a fixed type

#include <iostream>
#include <vector>
#include "neuron.h"

class layer {

public:
  layer(int numNeurons, neuron *pN);
  ~layer();
  int size();
  int numInputs();
  int numOutputs();
  void showInputs(std::ostream &out, const char* msg);
  void showWeights(std::ostream &out, const char *msg);
  void showOutputs(std::ostream &out, const char *msg);
  double output(int selectOutput);
  void input(int selectInput, double value);
  void weight(int selectWeight, int selectNeuron, double value);

private:
  std::vector<neuron*> _neurons;
};

//----< return number of neurons in layer >--------------------

inline int layer::size() { return _neurons.size(); }

//----< return number of layer inputs >------------------------
//
//  assumes that:
//    - all neurons in a layer have the same number of inputs
//    - every layer input connects to every neuron
//
inline int layer::numInputs() { return _neurons[0]->size(); }

//----< return number of layer outputs >-----------------------
//
//  assumes that each neuron output is a layer output
//
inline int layer::numOutputs() { return size(); }

#endif