#include "app.h"

#include <mbedtls/md.h>

const char *APP_VERSION = "0.1.0";
const char *PROJECT_NAME_VALUE = PROJECT_NAME;
const char *DEFAULT_ADMIN = "admin";
const char *DEFAULT_UPDATE_URL = "http://example.com/update.tslpkg";
const uint32_t FACTORY_RESET_HOLD_MS = 10000;
const size_t MAX_USERS = 8;
const size_t MAX_TOKENS = 8;
const bool DEFAULT_LED_INVERTED = true;
const byte DNS_PORT = 53;
const IPAddress SETUP_AP_IP(192, 168, 1, 1);
const IPAddress SETUP_AP_GATEWAY(192, 168, 1, 1);
const IPAddress SETUP_AP_SUBNET(255, 255, 255, 0);

WebServer server(80);
DNSServer dnsServer;
Preferences prefs;
Token tokens[8];
LogLevel currentLogLevel = LOG_INFO;
size_t maxLogBytes = 50 * 1024;
bool setupMode = false;
uint8_t ledBrightness = 0;
bool ledInverted = DEFAULT_LED_INVERTED;
String updateUrl = DEFAULT_UPDATE_URL;
String networkHostname;
bool networkDhcp = true;
String networkIp;
String networkGateway;
String networkSubnet;
String networkDns1;
String networkDns2;

String chipId() {
  uint64_t mac = ESP.getEfuseMac();
  char buf[13];
  snprintf(buf, sizeof(buf), "%04X%08X", (uint16_t)(mac >> 32), (uint32_t)mac);
  return String(buf);
}

String defaultDeviceName() {
  String suffix = chipId().substring(6);
  String base = PROJECT_NAME_VALUE;
  base.trim();
  for (size_t i = 0; i < base.length(); i++) {
    char c = base[i];
    if (!(isalnum(c) || c == '-')) base.setCharAt(i, '-');
  }
  while (base.startsWith("-")) base.remove(0, 1);
  while (base.endsWith("-")) base.remove(base.length() - 1);
  if (!base.length()) base = "ESP32C3";

  const size_t maxHostnameLength = 31;
  size_t maxBaseLength = maxHostnameLength - 1 - suffix.length();
  if (base.length() > maxBaseLength) base = base.substring(0, maxBaseLength);
  while (base.endsWith("-")) base.remove(base.length() - 1);
  return base + "-" + suffix;
}

String deviceName() {
  return networkHostname.length() ? networkHostname : defaultDeviceName();
}

String sha256(const String &input) {
  uint8_t digest[32];
  mbedtls_md_context_t ctx;
  mbedtls_md_init(&ctx);
  mbedtls_md_setup(&ctx, mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), 0);
  mbedtls_md_starts(&ctx);
  mbedtls_md_update(&ctx, (const unsigned char *)input.c_str(), input.length());
  mbedtls_md_finish(&ctx, digest);
  mbedtls_md_free(&ctx);
  char out[65];
  for (int i = 0; i < 32; i++) snprintf(out + (i * 2), 3, "%02x", digest[i]);
  out[64] = 0;
  return String(out);
}

String passwordHash(const String &password) {
  return sha256(chipId() + ":" + password);
}

String prefString(const char *key, const String &fallback) {
  return prefs.isKey(key) ? prefs.getString(key, fallback) : fallback;
}

void loadSettings() {
  prefs.begin("boiler", false);
  if (!prefs.getBool("ledPolV2", false)) {
    prefs.putBool("ledInv", DEFAULT_LED_INVERTED);
    prefs.putBool("ledPolV2", true);
  }
  uint8_t rawLogLevel = prefs.getUChar("logLevel", LOG_INFO);
  if (!prefs.getBool("logLevelV2", false)) {
    if (prefs.isKey("logLevel") && rawLogLevel >= 2) rawLogLevel++;
    rawLogLevel = constrain(rawLogLevel, 0, 4);
    prefs.putUChar("logLevel", rawLogLevel);
    prefs.putBool("logLevelV2", true);
  }
  currentLogLevel = (LogLevel)constrain(rawLogLevel, 0, 4);
  maxLogBytes = prefs.getUInt("logMax", 50 * 1024);
  ledInverted = prefs.getBool("ledInv", DEFAULT_LED_INVERTED);
  ledBrightness = constrain(prefs.getUChar("ledBright", 0), 0, 100);
  updateUrl = prefString("updateUrl", DEFAULT_UPDATE_URL);
  networkHostname = prefString("netHost", "");
  networkDhcp = prefs.getBool("netDhcp", true);
  networkIp = prefString("netIp", "");
  networkGateway = prefString("netGw", "");
  networkSubnet = prefString("netMask", "");
  networkDns1 = prefString("netDns1", "");
  networkDns2 = prefString("netDns2", "");
}