#pragma once

#include "esphome/components/esp32_ble_tracker/esp32_ble_tracker.h"

#include <cstdint>
#include <cstdio>
#include <string>

namespace esphome {
namespace ap2_hub {

namespace espbt = esphome::esp32_ble_tracker;

/* xTool AP2 Nordic-UART service + the F0F7 / M-code framing, shared by the
 * control slots and the scan prober. See SPEC.md for the full protocol. */

inline espbt::ESPBTUUID nus_svc() {
  return espbt::ESPBTUUID::from_raw("6e400001-b5a3-f393-e0a9-e50e24dcca9e");
}
inline espbt::ESPBTUUID nus_rx() {
  return espbt::ESPBTUUID::from_raw("6e400002-b5a3-f393-e0a9-e50e24dcca9e");
}
inline espbt::ESPBTUUID nus_tx() {
  return espbt::ESPBTUUID::from_raw("6e400003-b5a3-f393-e0a9-e50e24dcca9e");
}

/* Build an F0F7 frame for an ASCII M-code into f (>= 64 bytes). Returns length. */
inline uint8_t ap2_build_frame(const char *cmd, uint8_t seq, uint8_t *f) {
  static const uint8_t AP2_ID[3] = {0x45, 0x73, 0x60};  // PURIFIER_V2 device id/prefix
  uint8_t i = 0, sum = 0, start;
  f[i++] = 0xF0;
  start = i;
  f[i++] = AP2_ID[0];
  f[i++] = AP2_ID[1];
  f[i++] = AP2_ID[2];
  f[i++] = 0x01;
  f[i++] = seq;
  for (const char *p = cmd; *p != '\0'; ++p)
    f[i++] = (uint8_t) *p;
  f[i++] = 0x0A;
  for (uint8_t j = start; j < i; j++)
    sum += f[j];
  f[i++] = sum & 0x7F;
  f[i++] = 0xF7;
  return i;
}

/* Printable-ASCII view of a notification payload. */
inline std::string ap2_ascii(const uint8_t *data, uint16_t len) {
  std::string s;
  s.reserve(len);
  for (uint16_t k = 0; k < len; k++) {
    uint8_t c = data[k];
    if (c >= 32 && c < 127)
      s += (char) c;
  }
  return s;
}

/* If s is an M99 reply, return the firmware string (after 'V', up to a space),
 * else "". A non-empty result is the definitive "this is an AP2" fingerprint. */
inline std::string ap2_parse_m99_fw(const std::string &s) {
  auto p = s.find("M99");
  if (p == std::string::npos)
    return "";
  auto v = s.find('V', p);
  if (v == std::string::npos)
    return "";
  auto e = s.find(' ', v);
  return s.substr(v + 1, e == std::string::npos ? std::string::npos : e - (v + 1));
}

/* 0xAABBCCDDEEFF -> "AA:BB:CC:DD:EE:FF"; 0 -> "". */
inline std::string ap2_format_mac(uint64_t mac) {
  if (mac == 0)
    return "";
  char b[18];
  snprintf(b, sizeof(b), "%02X:%02X:%02X:%02X:%02X:%02X", (unsigned) ((mac >> 40) & 0xFF),
           (unsigned) ((mac >> 32) & 0xFF), (unsigned) ((mac >> 24) & 0xFF),
           (unsigned) ((mac >> 16) & 0xFF), (unsigned) ((mac >> 8) & 0xFF), (unsigned) (mac & 0xFF));
  return b;
}

}  // namespace ap2_hub
}  // namespace esphome