#! /usr/bin/env python
# -*- coding: cp1252 -*-
'''
***************************************************************************************
                      S M O L A - 2 0 0 6   S U R V E Y

        S h o t p o i n t   t i m e   r e c o n s t r u c t i o n
        - - - - - - - - -   - - - -   - - - - - - - - - - - - - -

DESCRIPTION:
    This Python script extracts position and time from automatic logging computer
    data files. This computer logs time and position every minute, independent of
    any survey line. Both time and position are GPS based.

    In order to reconstruct shotpoint times fram the Smøla-2006 Survey we first
    need to interpolate the minute-files so we can obtain time of an arbitrary point
    along the survey line (subject to size of interpolation step).

    Combining shotpoint positions with interpolated position/time values we can
    determine interpolated time of shotpoint.

    A brief time offset must be added to the interpolated shotpoint values to account
    for the delay between the EIVA Survey computer actually issuing the shot command,
    and the Gun Controller firing time. (This is performed in a later processing stage).

INPUT FILE:
    File from automatic logging computer, containing minute reading of date, time
    and position. Filename: See constant declaration section below.

OUTPUT FILES:
    Two files generated (as later interpolation deals with Easting/Northing
    separately):
       a) Time and Easting
       b) Time and Northing
    Names of output files: See constant declaration section below.

OTHER ASSUMPTIONS:
    This program file must be placed "above" input file directory called "logs".

EXTERNAL LIBRARY USED:
    UTM to Lat/Long conversion - download library from:
    http://www.pygps.org/#LatLongUTMconversion
    Either:
    a) On Linux: Unpack it, and run "python setup.py install" as root.
       In order to build Python modules you must first install 'python-devel'.
    b) Windows/Linux: Put "LatLongUTMconversion.py" in the same directory as this file.

VERSION:

    Ver  Date         By         Description
    ----------------------------------------------------------------------------------
    0.1  14 Aug 2007  O.Meyer    Initial version
    ----------------------------------------------------------------------------------

                               Dept. of Earth Science
                                University of Bergen
                                    N O R W A Y
***************************************************************************************
'''
import LatLongUTMconversion
from string  import split
from os.path import join
from datetime import datetime
from time import strptime

WGS84 = 23                  # Datum constant, see LatLongUTMconversion file

#-----  Directory, file names
DataDirectory    = './logs'
DataFile         = 'toktlogger-24-25-okt-2006.txt'
TimeEastingFile  = 'time_easting.txt'
TimeNorthingFile = 'time_northing.txt'

#---------------------------------------------------------------------
#-----            S t a r t   o f   p r o g r a m
#---------------------------------------------------------------------

#-----  Example format line in input file:
#-----     1,2006622,24.10.2006,134210.21,3100,000,000,-1,-1,-1,-1,  170.358,6327.44758 N,00706.58098 E,  264.93,-1,-1,-1,    7.90,   11.90,    8.70,   37.95,  994.80,  57,2,8,3,0,-1,    5.00, 267,,*5c

#--- We need to output all positions with a time value in seconds, since a reference point in time
#--- This reference point is set in the next statement, to 24/10/2006, 00:00:00.000000

BaseTime = datetime(2006,10,24,0,0,0,0)

#---- One input file, two output files

f_in  = open(join(DataDirectory,DataFile))
f_E   = open(TimeEastingFile,  "w")
f_N   = open(TimeNorthingFile, "w")

for line in f_in:                           #<<<<<<-- Loop throgh all lines in input file
    s = line.split(',')
    Day       = s[2].split('.')[0]
    Month     = s[2].split('.')[1]
    Year      = s[2].split('.')[2]
    Hour      = s[3][0:2]
    Minute    = s[3][2:4]
    Seconds   = s[3][4:6]
    Microsec  = int(s[3].split('.')[1]) * 10000
    Latitude  = s[12].split()[0]    # s[12] holds string like '6324.99468 N'
    Longitude = s[13].split()[0]    # s[13] holds string like '00706.58098 E'

    #--- Convert lat/long to decimal degrees, and then to UTM Easting/Northing
    Latitude  = int(Latitude[0:2])  + (float(Latitude[2:])/60.0)
    Longitude = int(Longitude[0:3]) + (float(Longitude[3:])/60.0)
    (z, e, n) = LatLongUTMconversion.LLtoUTM(WGS84, Latitude, Longitude)

    #--- Create Datetime object from current time values
    #print '%s-%s-%s  %02s:%02s:%02s.%06d' % (Day, Month, Year, Hour, Minute, Seconds, Microsec)
    TimeStamp = datetime(   int(Year),
                            int(Month),
                            int(Day),
                            int(Hour),
                            int(Minute),
                            int(Seconds),
                            Microsec
                            )
    #--- Calculate time delta: Difference between time in current line, and base time at midnight 24. Oct.
    TimeDelta = TimeStamp - BaseTime

    #--- Convert this time delta to number of seconds, with fractional part
    TimeDeltaAsFloat = (TimeDelta.days * 86400) + TimeDelta.seconds + (TimeDelta.microseconds/1000000.0)

    #--- Write to output files
    f_E.write('%1.3f %1.1f\n' % (TimeDeltaAsFloat, e))
    f_N.write('%1.3f %1.1f\n' % (TimeDeltaAsFloat, n))

f_E.close()
f_N.close()
f_in.close()