#include <wiringPi.h>
#include <wiringPiSPI.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <libconfig.h>
#include <math.h>

#include "LS7366R.h"
#include "ringbuffer.h"
#include "led.h"
#include "logging.h"


extern char VERSION[];
extern uint32_t REFCNT;

const int CTRL_OUT = 16;
const int INTR_IN  = 19;
const int SPI_CHAN = 0;
const int SPI_SPEED = 1000000;

config_t cfg;

const char EPSILON_KEY[] = "epsilon";
const double DEFAULT_EPSILON = 0.01;

uint32_t skipped = 0;


void isr() {
  static uint32_t lastCounter = 0;

  uint32_t currentCounter = ls7366rReadOTR();

  uint32_t diff = currentCounter - lastCounter;
  lastCounter = currentCounter;

  ringbufferPut(diff);
  led(E_GREEN, true);
}

void init() {
  wiringPiSetupGpio();

  wiringPiSPISetup(SPI_CHAN, SPI_SPEED);

  pinMode(CTRL_OUT, OUTPUT);
  digitalWrite(CTRL_OUT, 0);

  pinMode(INTR_IN, INPUT);
}

void readConfig() {
  config_init(&cfg);
  if (! config_read_file(&cfg, "/opt/etc/counter.cfg")) {
    logmsg(LOG_ERR, "failed to read config file: %s:%d - %s\n",
        config_error_file(&cfg), config_error_line(&cfg),
        config_error_text(&cfg));
    config_destroy(&cfg);
    exit(-1);
  }
}

void start() {
  wiringPiISR(INTR_IN, INT_EDGE_RISING, isr);
}

int main (void) {
  fprintf(stderr, "VERSION: %s, REFCNT: %u\n", VERSION, REFCNT);

  readConfig();
  init();
  ledInit();
  ls7366rInit(SPI_CHAN);
  start();

  uint8_t ledTick = 0;  

  while (1) {
    uint32_t period = ringbufferGet();
  
    // add averaging and forming the struct here
    logmsg(LOG_DEBUG, "Period: %lu", period);

    ledTick++;
    if (ledTick == 50) {
      ledTick = 0;
      led(E_GREEN, false);
    }

  }

  // will never be reached
  config_destroy(&cfg);
}