//
// Arquiteturas de Alto Desempenho 2025/2026
//
// DETI Coin Miner - CPU implementation
//

#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include "aad_data_types.h"
#include "aad_utilities.h"
#include "aad_sha1_cpu.h"
#include "aad_vault.h"

static volatile int keep_running = 1;

void signal_handler(int signum)
{
  (void)signum;
  keep_running = 0;
}

//
// check if a hash starts with aad20250
//
static int is_valid_coin(u32_t *hash)
{
  return hash[0] == 0xAAD20250u;
}

//
// mine DETI coins using the CPU (no SIMD)
//
static void mine_coins_cpu(u64_t max_attempts)
{
  u32_t coin[14];
  u32_t hash[5];
  u64_t attempts = 0;
  u32_t coins_found = 0;

  // Initialize coin template: "DETI coin 2 " + variable content + "\n\x80"
  memset(coin, 0, sizeof(coin));

  // "DETI coin 2 " at the beginning
  ((u08_t *)coin)[0x0 ^ 3] = 'D';
  ((u08_t *)coin)[0x1 ^ 3] = 'E';
  ((u08_t *)coin)[0x2 ^ 3] = 'T';
  ((u08_t *)coin)[0x3 ^ 3] = 'I';
  ((u08_t *)coin)[0x4 ^ 3] = ' ';
  ((u08_t *)coin)[0x5 ^ 3] = 'c';
  ((u08_t *)coin)[0x6 ^ 3] = 'o';
  ((u08_t *)coin)[0x7 ^ 3] = 'i';
  ((u08_t *)coin)[0x8 ^ 3] = 'n';
  ((u08_t *)coin)[0x9 ^ 3] = ' ';
  ((u08_t *)coin)[0xa ^ 3] = '2';
  ((u08_t *)coin)[0xb ^ 3] = ' ';

  // Newline at position 54, padding at 55
  ((u08_t *)coin)[0x36 ^ 3] = '\n';
  ((u08_t *)coin)[0x37 ^ 3] = 0x80;

  // Variable part: positions 12-53 (42 bytes)
  // Initialize with a pattern
  for(int i = 12; i < 54; i++)
    ((u08_t *)coin)[i ^ 3] = 'A' + (i - 12) % 26;

  printf("Mining DETI coins using CPU (no SIMD)...\n");
  printf("Press Ctrl+C to stop\n\n");

  time_measurement();
  time_measurement();
  double start_time = wall_time_delta();

  while(keep_running && (max_attempts == 0 || attempts < max_attempts))
  {
    // Compute SHA1 hash
    sha1(coin, hash);
    attempts++;

    // Check if it's a valid coin
    if(is_valid_coin(hash))
    {
      coins_found++;
      printf("COIN FOUND! (attempt %llu)\n", (unsigned long long)attempts);
      save_coin(coin);
    }

    // Update the variable part (simple counter-based approach)
    // Increment from the end to beginning
    int pos = 53;
    while(pos >= 12)
    {
      u08_t *byte = &((u08_t *)coin)[pos ^ 3];
      if(*byte == '\n' || *byte == 0x80)
        *byte = 32; // Start from space

      (*byte)++;

      // Skip newline character
      if(*byte == '\n')
        (*byte)++;

      // Wrap around at 127 (printable ASCII limit)
      if(*byte >= 127)
      {
        *byte = 32; // Reset to space
        pos--; // Carry to next position
      }
      else
      {
        break; // No carry needed
      }
    }

    // Print progress every 1M attempts
    if(attempts % 1000000 == 0)
    {
      time_measurement();
      double current_time = wall_time_delta() - start_time;
      double rate = attempts / current_time;
      printf("Attempts: %llu, Rate: %.2f MH/s, Coins: %u\n",
             (unsigned long long)attempts, rate / 1e6, coins_found);
    }
  }

  time_measurement();
  double total_time = wall_time_delta() - start_time;

  printf("\n=== Mining Statistics ===\n");
  printf("Total attempts: %llu\n", (unsigned long long)attempts);
  printf("Total time: %.2f seconds\n", total_time);
  printf("Average rate: %.2f attempts/second\n", attempts / total_time);
  printf("Coins found: %u\n", coins_found);

  // Save any remaining coins
  save_coin(NULL);
}

int main(int argc, char *argv[])
{
  u64_t max_attempts = 0;

  // Set up signal handler for graceful shutdown
  signal(SIGINT, signal_handler);

  if(argc > 1)
  {
    max_attempts = strtoull(argv[1], NULL, 10);
    printf("Will perform %llu attempts\n", (unsigned long long)max_attempts);
  }
  else
  {
    printf("Usage: %s [max_attempts]\n", argv[0]);
    printf("Running indefinitely until Ctrl+C...\n");
  }

  mine_coins_cpu(max_attempts);

  return 0;
}