"""
 Read raw data from Arduino and then converted into actual resistance using parameters provided from top level
"""
from datetime import datetime
import serial, os, json
import serial.tools.list_ports
import numpy as np

# constant settings
SENSORS_MAX = 4  # maximum sensor ports
baud = 9600

settings = json.load(open('settings.json', 'r'))
resolution = settings["resolution"]
v_src = settings["v_src"]
v_in = settings["v_in"]
refRes = np.array(settings["refRes"])
sensor_ports = np.array(settings["sensor_ports"])  # ports that sensor(s) are connected to
file_name = settings["file_name"]
port = settings["port"]
if "- No Device -" in port:
    # TODO: set to writerandomvalues.py thing instead raise error
    print("this should generate random values base on # sensors given")
    exit(0)
else:
    controller = serial.Serial(port)

if np.any(sensor_ports >= SENSORS_MAX):
    raise ValueError("Port range is 0-3!")

# TODO: separate data in each run but still keep them in one csv file
while controller.isOpen():
    try:
        read_data = controller.readline().decode("utf-8")
        # use numpy so it can make list calculations easier (and possibly faster)
        dat_list = np.asarray(json.loads(read_data), dtype=np.int16)[:SENSORS_MAX]
        dat_sel = np.take(dat_list, sensor_ports) * v_in / resolution
        r_arr = np.take(refRes, sensor_ports) * (v_in / dat_sel - 1)
        # write + export values as .csv format
        dat = f", ".join(np.insert(r_arr.astype(str), 0, datetime.now().strftime('%H:%M:%S')))
        print(dat)
        f = open(file_name, "a", newline="", encoding="utf-8")
        f.write(dat + '\n')
        f.close()
    # except KeyboardInterrupt as e:
    #     print(e.__class__.__name__)
    #     break
    except json.decoder.JSONDecodeError:
        print('decoder error')