# https://gist.github.com/aallan/581ecf4dc92cd53e3a415b7c33a1147c
from machine import Pin
import network
import utime
import sys
import ntptime
import wlan

try:
  import usocket as socket
except:
  import socket

try:
  import ustruct as struct
except:
  import struct

INTERVAL = 1000  # millisecond

"""
  Unix time starts on Jan 1 1970. In seconds, that's 2208988800:
  (date(1970, 1, 1) - date(1900, 1, 1)).days * 24*60*60
  (70*365+17)*24*60*60 = 2208988800 =>UTC0
  28800 = 8*60*60
  2208960000 = 2208988800-28800
"""
# Optional UTC+8 offset time (seconds), if not set, UTC0
UTC_OFFSET = 28800 # 8 * 60 * 60
# NTP_DELTA = 2208988800 + UTC_OFFSET

# The NTP host can be configured at runtime by doing: ntptime.host = 'myhost.org'
# host = "pool.ntp.org"
host = "tw.pool.ntp.org"

# ntptime.host = "time.nist.gov"
# ntptime.host = "pool.ntp.org"
ntptime.host = "tw.pool.ntp.org"
# ntptime.host = "ntp.aliyun.com"
# ntptime.host = "time.google.com"

if(sys.platform=="esp8266"):
  led = Pin(2, Pin.OUT)
elif(sys.platform=="esp32"):
  led = Pin(2, Pin.OUT)
elif(sys.platform=="rp2"):
  led = Pin("LED", Pin.OUT)

def gettime():
  NTP_QUERY = bytearray(48)
  NTP_QUERY[0] = 0x1B
  addr = socket.getaddrinfo(host, 123)[0][-1]
  s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

  try:
    s.settimeout(10.0)
    res = s.sendto(NTP_QUERY, addr)
    msg = s.recv(48)
  finally:
    s.close()
  val = struct.unpack("!I", msg[40:44])[0]
  return val - NTP_DELTA

def settime():
  t = gettime()
  tm = utime.gmtime(t)
  machine.RTC().datetime((tm[0], tm[1], tm[2], tm[6] + 1, tm[3], tm[4], tm[5], 0))

def sync_time_with_retry():
  try:
    print("Syncing with NTP server...")
    # settime()
    ntptime.settime()
    print("Time synchronized.")
  except OSError as e:
    # print("Error syncing time:", e)
    if e.args[0] == 110: # ETIMEDOUT
      print("ETIMEDOUT error during time sync. Retrying in 5 seconds...")
      utime.sleep(5)
      sync_time_with_retry() # Recursive call to retry
    else:
      print(f"An unexpected error occurred: {e}")

# Start Function
if __name__ == '__main__':
  wlan.connect_wifi() # Connecting to WiFi Router
  utime.sleep_ms(1000)

  led.on()
  sync_time_with_retry()  # Synchronize the time
  print("NTP 時間同步完成!")
  led.off()

  lastTime = utime.ticks_ms()

  while True:
    try:
      currTime = utime.ticks_ms()
      if (currTime - lastTime > INTERVAL):
        lastTime = currTime
        led.toggle()
        # 獲取並顯示本地時間 (台灣時區 +8)
        # utime.localtime() 取得 UTC 時間，所以要加上 8 小時
        local_time_tuple = utime.localtime(utime.time() + UTC_OFFSET)
        print(f"目前本地時間 (UTC+8): {local_time_tuple}")
      
        # 也可以直接格式化輸出
        # print("本地時間:", time.strftime("%Y-%m-%d %H:%M:%S", local_time_tuple))
      utime.sleep_ms(100)
    except KeyboardInterrupt:
      print("Stop")
      break