# Using parts of the following scripts:
# 1. https://www.raspberrypi-spy.co.uk/2016/07/using-bme280-i2c-temperature-pressure-sensor-in-python/
# 2. http://ecorov.com/2017/08/03/i2c-gy-91.html
import time
import ustruct
import machine
import network
import usocket

# Globals
debug = 1
sensorid = 3
sensoraddr = 0x76
sendseconds = 60
secondstrywificonnect = 10
REG_DATA = 0xF7
REG_CONTROL = 0xF4
REG_CONFIG  = 0xF5
REG_CONTROL_HUM = 0xF2
REG_HUM_MSB = 0xFD
REG_HUM_LSB = 0xFE
OVERSAMPLE_TEMP = 2
OVERSAMPLE_PRES = 2
MODE = 1

if debug:
	print(str(time.ticks_ms()) + ': ***STARTUP***')
	print(str(time.ticks_ms()) + ': sensorid: ' + str(sensorid))
	print(str(time.ticks_ms()) + ': sensoraddr: ' + str(sensoraddr))
	print(str(time.ticks_ms()) + ': sendseconds: ' + str(sendseconds))
	print(str(time.ticks_ms()) + ': secondstrywificonnect: ' + str(secondstrywificonnect))
	print(str(time.ticks_ms()) + ': REG_DATA: ' + str(REG_DATA))
	print(str(time.ticks_ms()) + ': REG_CONTROL: ' + str(REG_CONTROL))
	print(str(time.ticks_ms()) + ': REG_CONFIG: ' + str(REG_CONFIG))
	print(str(time.ticks_ms()) + ': REG_CONTROL_HUM: ' + str(REG_CONTROL_HUM))
	print(str(time.ticks_ms()) + ': REG_HUM_MSB: ' + str(REG_HUM_MSB))
	print(str(time.ticks_ms()) + ': REG_HUM_LSB: ' + str(REG_HUM_LSB))
	print(str(time.ticks_ms()) + ': OVERSAMPLE_TEMP: ' + str(OVERSAMPLE_TEMP))
	print(str(time.ticks_ms()) + ': OVERSAMPLE_PRES: ' + str(OVERSAMPLE_PRES))
	print(str(time.ticks_ms()) + ': MODE: ' + str(MODE))

# Activate a time which will reset us in sendseconds if we're hanging somewhere!
if debug:
	print(str(time.ticks_ms()) + ': Activating Timer')
tim = machine.Timer(-1) 
tim.init(period = sendseconds * 1000, mode = machine.Timer.ONE_SHOT, callback = lambda t:machine.reset())

# Activate the internal RTC (we don't need the time, but we want to know when a minute has passed!)
if debug:
	print(str(time.ticks_ms()) + ': Activating RTC')
rtc = machine.RTC()
# create a RTC alarm that expires after 60 seconds
rtc.irq(trigger = rtc.ALARM0, wake = machine.DEEPSLEEP)
rtc.alarm(rtc.ALARM0, sendseconds * 1000)
if debug:
	print(str(time.ticks_ms()) + ': RTC Time now: ' + '{:02}'.format(rtc.datetime()[2]) + '.' + '{:02}'.format(rtc.datetime()[1]) + '.' + '{:04}'.format(rtc.datetime()[0]) + ' ' + '{:02}'.format(rtc.datetime()[4]) + ':' + '{:02}'.format(rtc.datetime()[5]) + ':' + '{:02}'.format(rtc.datetime()[6]))

# Any exception will send us into deepsleep (where our rtc will wake us!)
try:
	if debug:
		print(str(time.ticks_ms()) + ': Trying to connect')
	# Connect to WiFi -> Get interfaces
	sta_if = network.WLAN(network.STA_IF)
	ap_if = network.WLAN(network.AP_IF)
	# Deactivate access point, we're station only
	ap_if.active(False)
	# Now connect
	connectcount = 0
	if not sta_if.isconnected():
		sta_if.active(True)
		sta_if.connect('myWifi', 'myPass')
		while not sta_if.isconnected():
			connectcount = connectcount + 1
			time.sleep(1)
			if debug:
				print(str(time.ticks_ms()) + ': Connect try: ' + str(connectcount))
			if connectcount > secondstrywificonnect:
				# We didn't connect after secondstrywificonnect seconds. Let's sleep
				if debug:
					print(str(time.ticks_ms()) + ': Connect failed after ' + str(connectcount) + ' seconds sleep. Going to deepsleep')
				machine.deepsleep()
	
	# Startup I2C
	if debug:
		print(str(time.ticks_ms()) + ': Starting I2C')
	i2c = machine.I2C(scl = machine.Pin(5), sda = machine.Pin(4), freq = 100000)
	
	# Set Oversampling
	if debug:
		print(str(time.ticks_ms()) + ': Setting BME280 Oversampling')
	OVERSAMPLE_HUM = 2
	i2c.writeto_mem(sensoraddr, REG_CONTROL_HUM, bytearray([OVERSAMPLE_HUM]))
	control = OVERSAMPLE_TEMP << 5 | OVERSAMPLE_PRES << 2 | MODE
	i2c.writeto_mem(sensoraddr, REG_CONTROL, bytearray([control]))
	
	# Read Calibration data from sensor
	if debug:
		print(str(time.ticks_ms()) + ': Getting BME280 Calibration data')
	cal1 = i2c.readfrom_mem(sensoraddr, 0x88, 24)
	cal2 = i2c.readfrom_mem(sensoraddr, 0xA1, 1)
	cal3 = i2c.readfrom_mem(sensoraddr, 0xE1, 7)
	
	# Convert bytes to words
	dig_T1 = ustruct.unpack('H', cal1[0:2])[0]
	dig_T2 = ustruct.unpack('h', cal1[2:4])[0]
	dig_T3 = ustruct.unpack('h', cal1[4:6])[0]
	dig_P1 = ustruct.unpack('H', cal1[6:8])[0]
	dig_P2 = ustruct.unpack('h', cal1[8:10])[0]
	dig_P3 = ustruct.unpack('h', cal1[10:12])[0]
	dig_P4 = ustruct.unpack('h', cal1[12:14])[0]
	dig_P5 = ustruct.unpack('h', cal1[14:16])[0]
	dig_P6 = ustruct.unpack('h', cal1[16:18])[0]
	dig_P7 = ustruct.unpack('h', cal1[18:20])[0]
	dig_P8 = ustruct.unpack('h', cal1[20:22])[0]
	dig_P9 = ustruct.unpack('h', cal1[22:24])[0]
	dig_H1 = ustruct.unpack('B', cal2[0:1])[0]
	dig_H2 = ustruct.unpack('h', cal3[0:2])[0]
	dig_H3 = ustruct.unpack('B', cal3[2:3])[0]
	dig_H4 = ustruct.unpack('b', cal3[3:4])[0]
	dig_H4 = (dig_H4 << 24) >> 20
	dig_H4 = dig_H4 | (ustruct.unpack('b', cal3[4:5])[0] & 0x0F)
	dig_H5 = ustruct.unpack('b', cal3[5:6])[0]
	dig_H5 = (dig_H5 << 24) >> 20
	dig_H5 = dig_H5 | (ustruct.unpack('B', cal3[4:5])[0] >> 4 & 0x0F)
	dig_H6 = ustruct.unpack('b', cal3[6:7])[0]
	
	# Wait in ms (Datasheet Appendix B: Measurement time and current calculation)
	if debug:
		print(str(time.ticks_ms()) + ': Sleeping for BME280 to be ready')
	wait_time = 1.25 + (2.3 * OVERSAMPLE_TEMP) + ((2.3 * OVERSAMPLE_PRES) + 0.575) + ((2.3 * OVERSAMPLE_HUM)+0.575)
	time.sleep(wait_time/1000)
	
	# Read temperature/pressure/humidity
	if debug:
		print(str(time.ticks_ms()) + ': Reading BME280')
	data = i2c.readfrom_mem(sensoraddr, REG_DATA, 8)
	pres_raw = (data[0] << 12) | (data[1] << 4) | (data[2] >> 4)
	temp_raw = (data[3] << 12) | (data[4] << 4) | (data[5] >> 4)
	hum_raw = (data[6] << 8) | data[7]
	
	# Refine temperature
	if debug:
		print(str(time.ticks_ms()) + ': Refine temperature')	
	var1 = ((((temp_raw>>3)-(dig_T1<<1)))*(dig_T2)) >> 11
	var2 = (((((temp_raw>>4) - (dig_T1)) * ((temp_raw>>4) - (dig_T1))) >> 12) * (dig_T3)) >> 14
	t_fine = var1 + var2
	temperature = float(((t_fine * 5) + 128) >> 8)
	
	# Refine pressure and adjust for temperature
	if debug:
		print(str(time.ticks_ms()) + ': Refine pressure')	
	var1 = t_fine / 2.0 - 64000.0
	var2 = var1 * var1 * dig_P6 / 32768.0
	var2 = var2 + var1 * dig_P5 * 2.0
	var2 = var2 / 4.0 + dig_P4 * 65536.0
	var1 = (dig_P3 * var1 * var1 / 524288.0 + dig_P2 * var1) / 524288.0
	var1 = (1.0 + var1 / 32768.0) * dig_P1
	if var1 == 0:
		pressure = 0
	else:
		pressure = 1048576.0 - pres_raw
		pressure = ((pressure - var2 / 4096.0) * 6250.0) / var1
		var1 = dig_P9 * pressure * pressure / 2147483648.0
		var2 = pressure * dig_P8 / 32768.0
		pressure = pressure + (var1 + var2 + dig_P7) / 16.0
	
	# Refine humidity
	if debug:
		print(str(time.ticks_ms()) + ': Refine humidity')	
	humidity = t_fine - 76800.0
	humidity = (hum_raw - (dig_H4 * 64.0 + dig_H5 / 16384.0 * humidity)) * (dig_H2 / 65536.0 * (1.0 + dig_H6 / 67108864.0 * humidity * (1.0 + dig_H3 / 67108864.0 * humidity)))
	humidity = humidity * (1.0 - dig_H1 * humidity / 524288.0)
	if humidity > 100:
		humidity = 100
	elif humidity < 0:
		humidity = 0
	
	# Data is ready
	temperature = temperature / 100.0
	pressure = pressure / 100.0
	humidity = humidity
	if debug:
		print(str(time.ticks_ms()) + ': Data fetched: temp ' + str(temperature) + ' - press ' + str(pressure) + ' - hum ' + str(humidity))
	
	# Send data to the Internet, a Post Request with http - we don't use SSL here!
	content = b'sensorid=' + str(sensorid) + '&temp=' + str(temperature) + '&press=' + str(pressure) + '&hum=' + str(humidity) + '&password=zzz'
	
	if debug:
		print(str(time.ticks_ms()) + ': Connecting to website')
	addr_info = usocket.getaddrinfo("meinserver.de", 80)
	addr = addr_info[0][-1]
	sock = usocket.socket()
	sock.connect(addr)
	sock.send(b'POST /tempsensor.php HTTP/1.1\r\n')
	sock.send(b'Host: meinserver.de\r\n')
	sock.send(b'Content-Type: application/x-www-form-urlencoded\r\n')
	sock.send(b'Content-Length: ' + str(len(content)) + '\r\n')
	sock.send(b'\r\n')
	if debug:
		print(str(time.ticks_ms()) + ': Sending: ' + str(content))
	sock.send(content)
	sock.send(b'\r\n\r\n')
	if debug:
		print(str(time.ticks_ms()) + ': Answer: ' + str(sock.recv(1000)))	
	sock.close()
	
	# Go to deep sleep (Device starts from reset again!) - Make sure that ESP8266 GPIO16 is connected to the RST Pin!
	if debug:
		print(str(time.ticks_ms()) + ': All done. DEEPSLEEP')
	machine.deepsleep()
except:
	if debug:
		print(str(time.ticks_ms()) + ': Exception happend. DEEPSLEEP')
	machine.deepsleep()