import csv
import re
import sys
import numpy as np
import struct
from time import ctime
from datetime import date, datetime, time, timedelta

####### CHANGE THIS PATH #######
filename = '/home/john/zRamdisk/SierraData/F.US.HSIN19.scid'

def deserialize(excelDateAndTime):
    """
    Returns excel date time as Python datetime object
    """
    date_tok = int(excelDateAndTime)
    time_tok = round(86400*(excelDateAndTime - date_tok))
    d = date(1899, 12, 31) + timedelta(date_tok)
    t = time(*helper(time_tok, (24, 60, 60, 1000000)))
    return datetime.combine(d, t)


def helper(factor, units):
    factor /= 86399.99
    result = list()
    for unit in units:
        value, factor = divmod(factor * unit, 1)
        result.append(int(value))
    result[3] = int(0)
    return result


def datetimeTwo(excelDateAndTime, tzAdjust):
    """
    Returns excel date time in format YYYYMMDD HHMMSS
    """
    t = str(deserialize(excelDateAndTime + tzAdjust.seconds/86400.0))
    return (re.sub(r'(:|-)', '', t)[:8], re.sub(r'(:|-)', '', t)[9:15])


def excelTimeAdjust(date_and_time, tzAdjust):
    return date_and_time + tzAdjust.seconds/86400.0


def getRecords(filename, fileoutput, tzvar, dtformat):
    """
    Read in records from SierraChart .scid data filename
    dtformat determines the datetime representation in column 1 (and 2)
    """
    sizeHeader = 0x38
    sizeRecord = 0x28
    if tzvar == 99999:
        tzAdjust = datetime.fromtimestamp(0) - datetime.utcfromtimestamp(0)
    else:
        tzAdjust = timedelta(hours=tzvar)

    header = ('Date', 'Time', 'O', 'H', 'L', 'C', 'V', 'T')
    ftsv = open(fileoutput, 'w')
    fileout = csv.writer(ftsv, delimiter='\t')
    with open(filename, 'rb') as fscid:
        fscid.read(sizeHeader)  # discard header
        fileout.writerow(header)
        for i in range(300000):
            data = fscid.read(sizeRecord)
            if data != "" and len(data) == sizeRecord:
                dataRow = struct.unpack('d4f4I', data)
                if dtformat == 0:
                    adjustedTime = dataRow[0] + tzAdjust.seconds/86400.0
                    outrow = (str(adjustedTime), str(adjustedTime),
                              str(dataRow[1]), str(dataRow[2]), str(dataRow[3]),
                              str(dataRow[4]), str(dataRow[5]), str(dataRow[6]))
                    fileout.writerow(outrow)
                elif dtformat == 1:
                    date, time = datetimeTwo(dataRow[0], tzAdjust)
                    outrow = (date, time,
                              str(dataRow[1]), str(dataRow[2]), str(dataRow[3]),
                              str(dataRow[4]), str(dataRow[5]), str(dataRow[6]))
                    fileout.writerow(outrow)
            else:
                break
    return


if __name__ == '__main__':
    """
    Takes a SierraChart scid file (input argument 1) and converts
      it to a tab separated file (tsv)
    Timezone conversion can follow the users local timezone, or a
      specified integer (input l or an integer but if the default
      filename is being used, '' must be specified for the filename)
    """
    tzvar = 0
    if len(sys.argv) > 1:
        if len(sys.argv[1]):
            filename = sys.argv[1]
        if len(sys.argv) > 2 and len(sys.argv[2]):
            print(sys.argv[2], type(sys.argv[2]))
            if sys.argv[2] == 'l':
                tzvar = 99999
                print(tzvar, type(tzvar))
            else:
                tzvar = float(sys.argv[2])
                print(tzvar, type(tzvar))
    fileoutput = filename[:-4] + 'tsv'
    getRecords(filename, fileoutput, tzvar, 1)