import binascii
import serial
from dataclasses import dataclass
from typing import List
from messaging.sms import SmsDeliver, SmsSubmit
from time import sleep


class ModemException(Exception):
	pass

class InvalidResponseException(ModemException):
	def __init__(self, message):
		super().__init__('Invalid response from modem: ' + message)


def b(value):
	if isinstance(value, str):
		return value.encode('utf-8')
	return value

def encode_utf16(value):
	if isinstance(value, bytes):
		value = value.decode('utf-8')
	return binascii.hexlify(value.encode('utf-16-be'))

def decode_utf16(value):
	return bytes.fromhex(value).decode('utf-16-be').replace('\x1b\x14', '^')

def parse_response(line):
	values = line.split(': ')[1].split(',')
	# because FUCKING AT HAS COMMAS IN STRINGS
	for i in range(len(values)):
		value = values[i]
		if len(value) > 0 and value[0] == '"' and value[-1] != '"':
			values[i] = values[i] + ',' + values[i+1]
			values[i+1] = None
	values = filter(lambda x: x is not None, values)

	def mapper(value):
		value = value.strip()
		if len(value) == 0:
			return None
		if value.isnumeric():
			return int(value)
		if value[0] == '"' and value[-1] == '"':
			return value[1:-1]
	return list(map(mapper, values))


class Modem:
	def __init__(self, port):
		self.serial = serial.Serial(port, 460800, timeout=0.1)
		self.reset()

	def send(self, data):
		data = b(data)                # encode as bytes (if string)
		if not data.endswith(b'\r'):  # add \r to the end of message
			data += b'\r'
		print('req', data)
		self.serial.write(data)       # write to the modem
		res = self.serial.readall()   # get modem's response
		print('res', res)
		res = res[len(data):]         # remove echo
		res = res.strip()             # remove whitespace
		return res.decode('utf-8')    # decode to string

	def reset(self):
		self.send('ATE1')
		res = self.send('ATZ')
		if res != 'OK':
			raise InvalidResponseException(res)
		self.set('CMGF', 0)

	def set(self, property, *params, **kwargs):
		msg = b'AT+' + b(property) + b'='
		for param in params:
			if isinstance(param, str):
				msg += b'"' + param.encode('utf-8') + b'"'
			if isinstance(param, int):
				msg += str(param).encode('utf-8')
			if isinstance(param, bytes):
				msg += b'"' + param + b'"'
			msg += b','
		# trim the last comma
		msg = msg[:-1]
		res = self.send(msg)
		# accept '>' because of CMGS and '' because it may be already set
		# also accept when response starts with + because it has data
		if res not in ('OK', '>', '') and res[0] != '+':
			raise InvalidResponseException(res)
		return res

	def query(self, property):
		msg = b'AT+' + b(property) + b'?'
		res = self.send(msg)
		return parse_response(res.split('\n')[0])

	def send_sms(self, number, message):
		submit = SmsSubmit(number, message)
		csca = self.query('CSCA')[0]
		if '+' in csca:
			submit.csca = csca
		else:
			submit.csca = decode_utf16(csca)
		for pdu in submit.to_pdu():
			self.set('CMGS', int(pdu.length))
			res = self.send(pdu.pdu.encode('utf-8') + b'\x1a')
			while '+CMGS: ' not in res:
				sleep(1)
				res = self.serial.readall().decode('utf-8')

	def list_sms(self):
		res = self.set('CMGL', 4)
		lines = res.split('\r\n')
		messages = []
		print(lines)

		for i in range(int(len(lines)/2)):
			if lines[2*i] == '':
				continue
			header = parse_response(lines[2*i])
			content = lines[2*i+1]

			sms = SMS(content)
			sms.mid = header[0]
			sms.parts = []
			sms.__modem__ = self
			
			messages.append(sms)

		for i in range(len(messages)):
			message = messages[i]
			if message is None:
				continue
			if message.udh is None or message.udh.concat is None:
				continue
			for j in range(i+1, len(messages)):
				next_message = messages[j]
				if next_message.udh is None or next_message.udh.concat is None:
					continue
				if message.udh.concat.ref == next_message.udh.concat.ref:
					message.text += next_message.text
					message.parts.append(next_message.mid)
					messages[j] = None

		messages = list(filter(lambda x: x is not None, messages))

		return messages

	def remove_sms(self, sms):
		self.set('CMGD', sms.mid, 0)
		for part in sms.parts:
			self.set('CMGD', part, 0)


class SMS(SmsDeliver):
	mid: int
	parts: List[int]
	__modem__: Modem

	def remove(self):
		self.__modem__.remove_sms(self)