import time
import os
import GPIBPrologix
import csv
import datetime
import bme280
import smbus2

NUMMEAS = 3
NUMSAMPLES = 20
NUMCHANNELS = 7
NULLINGCHANNEL = 7
SCANNERSLOT = 2
BASESAVENAME = "Prod_VoltageBankLog_Ch"

bus = smbus2.SMBus(1)
calibration_params = bme280.load_calibration_params(bus, 0x76)
GPIB = GPIBPrologix.ResourceManager("/dev/ttyACM0")
inst2 = GPIB.open_resource(29)
inst1 = GPIB.open_resource(28)

def openCloseGPIB(openClose):
    global GPIB
    global inst1
    global inst2
    if openClose == "close":
        GPIB.close
    elif openClose == "open":
        GPIB = GPIBPrologix.ResourceManager("/dev/ttyACM0")
        inst2 = GPIB.open_resource(29)
        inst1 = GPIB.open_resource(28)

def getEnvironment(instObj, i2cbus):
    value = instObj.sample(i2cbus, 0x76, calibration_params)
    return value

def closeChannel(instObj, scannerCardSlot, channel):
    print("----- Closing channel: "+str(channel)+" on slot: "+str(scannerCardSlot)+" -----")
    instObj.write(":ROUTe:CLOSe (@ "+str(scannerCardSlot)+"!"+str(channel)+")")

def openChannel(instObj, scannerCardSlot, channel = 9):
    if channel >= 9:
        instObj.write(":ROUTe:OPEN ALL")

def readNVM(instObj):
    # dummy reading for auto range
    instObj.write("I1,"+str(1)+"X")
    instObj.write("H0X")
    time.sleep(2)
    print("Selected range from dummy reading: ")
    # Set amount of samples
    instObj.write("I1,"+str(NUMSAMPLES)+"X")
    instObj.write("H0X")
    #openCloseGPIB("close")
    time.sleep(NUMSAMPLES*0.55)
    #openCloseGPIB("open")
    instObj.write("F2X")
    output = instObj.read().split(',')
    output = map(float, output)
    return (list(output))

def getMeanSTDev(values):
    mean = sum(values)/len(values)
    variance = sum([(x - mean) ** 2 for x in values]) / (len(values) - 1)
    stddev = variance ** 0.5
    #print(mean,variance,stddev)
    return mean, stddev

# NVM Setup
inst2.write("R0B1X")   # auto range
inst2.write("K2X")
inst2.write("O0P0N0W0X")
inst2.write("S2X")
inst2.write("T8X")     #manual trigger
inst2.write("F2X")     #All readings from buffer
inst2.write("G0X")
inst2.write("W1000X")  #1s trigger delay

# Scanner setup
inst1.write("*RST")
inst1.write(":ROUTe:CONFigure:SLOT1:CTYPe C7058")
inst1.write(":ROUTe:CONFigure:SLOT2:CTYPe C7168")
inst1.write(":ROUTe:CONFigure:SLOT2:POLE 2")
inst1.write(":ROUTe:OPEN ALL")
inst1.write(":DISP:ENAB 1")
inst1.write(":DISP:WIND1:TEXT:DATA ' '")
inst1.write(":DISP:WIND1:TEXT:STAT 1")
inst1.write(":DISP:WIND2:TEXT:DATA ' '")
inst1.write("DISP:WIND2:TEXT:STAT 1")

readings = []

for i in range(NUMCHANNELS):
    # get the nulled channel value
    closeChannel(inst1, SCANNERSLOT, NULLINGCHANNEL)
    print("NULLING...")
    nullMeanStats   = []
    nullStddevStats = []
    for nulling in range(NUMMEAS):
        nullReadings = readNVM(inst2)
        nullMean, nullStddev = getMeanSTDev(nullReadings)
        nullMeanStats.append(nullMean)
        nullStddevStats.append(nullStddev)
    openChannel(inst1, SCANNERSLOT, 9)

    # read value
    closeChannel(inst1, SCANNERSLOT, i+1)
    MeanStats   = []
    StddevStats = []
    for nulling in range(NUMMEAS):
        Readings = readNVM(inst2)
        Mean, Stddev = getMeanSTDev(Readings)
        MeanStats.append(Mean)
        StddevStats.append(Stddev)
    openChannel(inst1, SCANNERSLOT, 9)

    # compensate for nulling
    meanNull, x          = getMeanSTDev(nullMeanStats)
    stddevNull, x        = getMeanSTDev(nullMeanStats)
    meanMeas, x          = getMeanSTDev(MeanStats)
    stddevMeas, x        = getMeanSTDev(StddevStats)
    meanCompensated      = meanMeas - meanNull
    stddevCompensated    = stddevMeas + stddevNull
    d     = datetime.datetime.now()
    dx    = d - datetime.timedelta(microseconds=d.microsecond)
    data  = getEnvironment(bme280, bus)
    fields=[dx.strftime("%d-%m-%y %H:%M:%S"),i+1,round(meanNull,10),round(stddevNull,10),round(meanMeas,10),round(stddevMeas,10),round(meanCompensated,10),round(stddevCompensated,10),round(data.humidity,2),round(data.temperature,2),round(data.pressure,2)]
    print(fields)

    if not os.path.exists("data/"):
        os.makedirs("data/")
    if not os.path.exists("data/"+BASESAVENAME+str(i+1)+".csv"):
        with open("data/"+BASESAVENAME+str(i+1)+".csv", 'w') as file:
            file.writelines("DateTime;Channel;NullingMean;NullingStddev;MeasuredMean;MeasuredStddev;CompensatedMean;CompensatedStddev;EnvHumidity;EnvTemperature;EnvPressure")
    else:
        with open("data/"+BASESAVENAME+str(i+1)+".csv", 'a') as f:
            writer = csv.writer(f)
            writer.writerow(fields)
#inst1.write(":DISP:ENAB 0")
inst2.write("A1,''X")
#inst1.write(":DISP:TEXT:STAT 0")
GPIB.close()