#ifndef _BACKPROP_H_
#define _BACKPROP_H_

#define BIGRND 0x7fffffff

#define GPU
#define THREADS 256
#define WIDTH 16  // shared memory width
#define HEIGHT 16 // shared memory height

#define ETA 0.3      // eta value
#define MOMENTUM 0.3 // momentum value
#define NUM_THREAD 4 // OpenMP threads

typedef struct {
  int input_n;  /* number of input units */
  int hidden_n; /* number of hidden units */
  int output_n; /* number of output units */

  float *input_units;  /* the input units */
  float *hidden_units; /* the hidden units */
  float *output_units; /* the output units */

  float *hidden_delta; /* storage for hidden unit error */
  float *output_delta; /* storage for output unit error */

  float *target; /* storage for target vector */

  float **input_weights;  /* weights from input to hidden layer */
  float **hidden_weights; /* weights from hidden to output layer */

  /*** The next two are for momentum ***/
  float **input_prev_weights;  /* previous change on input to hidden wgt */
  float **hidden_prev_weights; /* previous change on hidden to output wgt */
} BPNN;

/*** User-level functions ***/

void bpnn_initialize();

BPNN *bpnn_create();
void bpnn_free();

void bpnn_train();
void bpnn_feedforward();

void bpnn_save();
BPNN *bpnn_read();

#endif