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#include "interruptsinterrupt.h" // interrupts are required for soft timers
#include "soft_timer.h" // for soft timers
#include "log.h" // for printing
#include "wait.h" // for wait function

#include <stdlib.h> // for random numbers
#include <stdint.h> // for integer types

#define COIN_FLIP_PERIOD_MS 1000 // milliseconds between coin flips

typedef struct CoinFlipStorage {
  uint16_t num_heads;
  uint16_t num_tails;
} CoinFlipStorage;

void prv_timer_callback(SoftTimerId timer_id, void *context) {
  CoinFlipStorage *storage = context; // cast void* to our struct so we can use it
  uint8_t coinflip = rand() % 2;
  if (coinflip == 1) storage->num_heads++;
  else if (coinflip == 0) storage->num_tails++;
  
  // log output
  LOG_DEBUG("Num heads: %i, num tails: %i\n", storage->num_heads, storage->num_tails);
  
  // start the timer again, so it keeps periodically flipping coins
  soft_timer_start_millis(COIN_FLIP_PERIOD_MS,
                          prv_timer_callback, 
                          storage, 
                          NULL);
}

int main() {
  srand(14); // seed the random number generator with (MS)XIV, our car number
  
  interrupt_init(); // interrupts must be initialized for soft timers to work
  soft_timer_init(); // soft timers must be initialized before using them
  
  CoinFlipStorage storage = { 0 }; // we use this to initialize a struct to be all 0
  
  soft_timer_start_millis(COIN_FLIP_PERIOD_MS, // timer duration
                          prv_timer_callback, // function to call after timer
                          &storage, // automatically gets cast to void*
                          NULL); // timer id - not needed here
  
  while (true) {
    wait(); // waits until an interrupt is triggered rather than endlessly spinning
  }
  
  return 0;
}