#include <stdio.h>
#include <stdlib.h>
#include "vpi_user.h"

#include "counter_tb_ports.h"
#include "counter_tb_exports.h"

//Definitions to hols the data to be passed from calltf rtn
typedef struct tagCounter32 {
  vpiHandle  clk;
  vpiHandle  d_out;

  vpiHandle  rst;
} inst_rec;

// CallBack Proto 
int sc_counter_calltf(char *user_data);
int sc_counter_interface(p_cb_data cb_data);

int sc_counter_calltf(char *user_data) {
  vpiHandle  inst_h, arg_iter;
  s_vpi_value  value_s;
  s_vpi_time  time_s;
  s_cb_data  cb_data_s;
  inst_rec  *ip;

  ip = (inst_rec *)malloc(sizeof(inst_rec));
  
  // Get Arguments to System Task 
  inst_h = vpi_handle(vpiSysTfCall, 0);
  arg_iter = vpi_iterate(vpiArgument, inst_h);

  ip->clk     = vpi_scan(arg_iter);  // 1nd argument 
  ip->d_out   = vpi_scan(arg_iter);  // 2st argument 
  ip->rst     = vpi_scan(arg_iter);  // 3st argument 
  
  vpi_free_object(arg_iter);
  
  // Set-Up Value Change callback option 
  cb_data_s.user_data = (char *)ip;
  cb_data_s.reason    = cbValueChange;
  cb_data_s.cb_rtn    = sc_counter_interface;
  cb_data_s.time      = &time_s;
  cb_data_s.value     = &value_s;

  time_s.type         = vpiSuppressTime;
  value_s.format      = vpiIntVal;

  cb_data_s.obj  = ip->clk;
  vpi_register_cb(&cb_data_s);

  cb_data_s.obj  = ip->d_out;
  vpi_register_cb(&cb_data_s);
  
  init_sc();  // Initialize SystemC Model

  return(0);
}

//Value change simulation callback routine
int sc_counter_interface(p_cb_data cb_data)
{
  inst_rec  *ip;
  s_vpi_value  value_s;
  
  static unsigned long SimNow = 0;

  // IO ports systemC testbench
  static INVECTOR   invector;
  static OUTVECTOR  outvector;
  
  ip = (inst_rec *)cb_data->user_data;
  
  // Read current value from Verilog 
  value_s.format = vpiIntVal;

  vpi_get_value(ip->clk, &value_s);
  invector.clk = value_s.value.integer;

  vpi_get_value(ip->d_out, &value_s);
  invector.d_out = value_s.value.integer;

  exec_sc(&invector, &outvector, (tf_gettime()-SimNow));
  SimNow = tf_gettime();

  value_s.value.integer = outvector.rst;
  vpi_put_value(ip->rst, &value_s, 0, vpiNoDelay);

  if (outvector.done) {
    tf_dofinish();
  }
  return(0);
}