import struct
from ubx.messages.msg import UbxMsg

class Sig(UbxMsg):
	def __init__(self):
		UbxMsg.__init__(self, 0x01, 0x43)

	class Group1:
		@classmethod
		def from_bytes(cls, data: bytes):
			obj = Sig.Group1()
			obj.gnss_id = struct.unpack("B", data[0:1])[0]
			obj.sv_id = struct.unpack("B", data[1:2])[0]
			obj.sig_id = struct.unpack("B", data[2:3])[0]
			obj.freq_id = struct.unpack("B", data[3:4])[0]
			obj.pr_res = struct.unpack("<H", data[4:6])[0]
			obj.cno = struct.unpack("B", data[6:7])[0]
			obj.quality_ind = struct.unpack("B", data[7:8])[0]
			obj.corr_source = struct.unpack("B", data[8:9])[0]
			obj.iono_model = struct.unpack("B", data[9:10])[0]
			obj.sig_flags = struct.unpack("<H", data[10:12])[0]
			obj.reserved1 = struct.unpack("BBBB", data[12:16])[0]
			return obj.__dict__

	@classmethod
	def from_bytes(cls, data: bytes):
		obj = Sig()
		obj.iTOW = struct.unpack("<L", data[0:4])[0]
		obj.version = struct.unpack("B", data[4:5])[0]
		obj.num_signals = struct.unpack("B", data[5:6])[0]
		obj.reserved = struct.unpack("BB", data[6:8])[0]
		obj.signals = []
		offset = 8
		remain = len(data) - offset
		group_size = 16
		n = offset
		while remain >= group_size:
			signal = cls.Group1.from_bytes(data[n:n + group_size])
			n += group_size
			remain -= group_size
			obj.signals.append(signal)
		if remain:
			print(f"Sig.from_bytes: {remain} trailing bytes unparsed (payload size mismatch)")
		return obj.__dict__

class Sat(UbxMsg):
	def __init__(self):
		UbxMsg.__init__(self, 0x01, 0x35)

	class Group1:
		@classmethod
		def from_bytes(cls, data: bytes):
			obj = Sat.Group1()
			obj.gnss_id = struct.unpack("B", data[0:1])[0]
			obj.sv_id = struct.unpack("B", data[1:2])[0]
			obj.cno = struct.unpack("B", data[2:3])[0]
			obj.elev = struct.unpack("B", data[3:4])[0]
			obj.azim = struct.unpack("<h", data[4:6])[0]
			obj.pr_res = struct.unpack("<h", data[6:8])[0]
			obj.flags = struct.unpack("<I", data[8:12])[0]
			return obj.__dict__

	@classmethod
	def from_bytes(cls, data: bytes):
		obj = Sat()
		obj.iTOW = struct.unpack("<L", data[0:4])[0]
		obj.version = struct.unpack("B", data[4:5])[0]
		obj.num_sv = struct.unpack("B", data[5:6])[0]
		obj.reserved0 = struct.unpack("BB", data[6:8])[0]
		obj.satellites = []
		offset = 8
		remain = len(data) - offset
		group_size = 12
		n = offset
		while remain >= group_size:
			satellite = cls.Group1.from_bytes(data[n:n + group_size])
			n += group_size
			remain -= group_size
			obj.satellites.append(satellite)
		if remain:
			print(f"Sat.from_bytes: {remain} trailing bytes unparsed (payload size mismatch)")
		return obj.__dict__