#include "clock.h"

#include <log.h>
#include <WiFi.h>
#include <wifi.h>

#define CLOCK_GMT_OFFSET_SECONDS        3600
#define CLOCK_DST_OFFSET_SECONDS        3600
#define CLOCK_NTP_SERVER2_URL           "de.pool.ntp.org"
#define CLOCK_EPOCH_SECONDS_MIN         1735686000

time_t clockOffset = 0;

time_t startupTime = 0;

auto ntpSet = false;

void clockLoop() {
  if (isClockSet()) {
    return;
  }

  if (!ntpSet && isWiFiConnected()) {
    configTime(CLOCK_GMT_OFFSET_SECONDS, CLOCK_DST_OFFSET_SECONDS, WiFi.gatewayIP().toString().c_str(), CLOCK_NTP_SERVER2_URL);
    ntpSet = true;
  }

  const auto now = time(nullptr);
  if (isCorrectTime(now)) {
    clockOffset = now;
  } else {
    startupTime = now - clockOffset;
    const auto startStr = String(ctime(&startupTime));
    info("clock set after %ld seconds! So startup was at %s", clockOffset, startStr.c_str());
  }
}

bool isClockSet() {
  return startupTime != 0;
}

String getClockStr() {
  const auto t = time(nullptr);
  return {ctime(&t)};
}

bool isCorrectTime(const time_t now) {
  return now < CLOCK_EPOCH_SECONDS_MIN;
}

time_t clockCorrect(const time_t t) {
  if (!isClockSet() || isCorrectTime(t)) {
    return t;
  }
  return t + clockOffset;
}

void clockCorrect(time_t *t) {
  if (!isClockSet() || isCorrectTime(*t)) {
    return;
  }
  *t += clockOffset;
}