#!/usr/bin/python
"""
Creates a full calc file.

Ties together vex2calcheader, vex2calcantenna, vex2sched and eop to create
a full calc file

It is very efficiently in that it reads the vex file multiple times
This may be a problem with very large vex files.

TODO add option to use input2calc.py?
"""
import sys
import getopt
from math import floor

from . import observation

from . import vex2calc.vex2calcheader as vex2calcheader
from . import vex2calc.vex2calcantenna as vex2calcantenna
from . import vex2calc.vex2sched as vex2sched
from . import vex2calc.eop as eop
from . import vex2calc.calcfooter as calcfooter

from .astro import datetime2mjd
from .vex2calc.readvex import VexSched


def main():
    """
Produce .calc file from a vex file.

Usage:
    vex2calc.py root

n.b. for experiments longer than one day you must
specify the number of days to ensure sufficient eop
parameters
    
Options:    
========
-p  --vexpath           vexpath (root.skd or root.vex by default)

vex2calcheader.py
    --obscode           obscode (root by default)
    --jobid             jobid
-i  --increment         increment
    --spectralaverage   spectralaverage
    --taperfunction     taperfunction

vex2calcantenna.py
-a  --antennas          antennas

vex2sched.py 
-o  --offset            offset
-t  --tail              tail

eop.py
-e  --extra             extra
-d  --download
-f  --force
-n  --ndays             integer number of days the observation lasts 

For more information on the options, see the docstrings of the individual
scripts in the vex2calc directory
    """
    if len(sys.argv) < 2:
        print(main.__doc__)
        sys.exit(2)
    try:
        opts, args = getopt.gnu_getopt(sys.argv[1:], "p:i:a:o:t:e:dfn:",
                     ["vexpath=",
                      "obscode=", "jobid=", "increment=", "spectralaverage=", "taperfunction=",
                      "antennas=", "offset=", "tail=",  "extra=", "download", "force", "ndays="])
    except getopt.GetoptError as err:
        print(err)
        print(main.__doc__)
        sys.exit(2)
    if not len(args) == 1:
        print('Error: Wrong number of arguments.')

    # read arguments
    root = args[0]

    # set defaults
    vex_path = root + '.skd'
    vex_path2 = root + '.vex'
    vex_path_opt = None

    obscode = root
    job_id = None
    increment = None
    spectral_average = None
    taper_function = None
    antennas = None
    offset = None
    tail = None
    extra = None
    download = None
    force = None
    ndays = 0

    # read options
    for o, a in opts:
        if o in ("-p", "--vexpath"):
            vex_path_opt = a
        elif o == "--obscode":
            obscode = a
        elif o == "--jobid":
            job_id = a
        elif o in ("-i", "--increment"):
            increment = int(a)
        elif o == "--spectralaverage":
            spectral_average =  a
        elif o == "--taperfunction":
            taper_function = a
        elif o in ("-a", "--antennas"):
            antennas = a.split()
        elif o in ("-o", "--offset"):
            offset = int(a)
        elif o in ("-t", "--tail"):
            tail = int(a)
        elif o in ("-e", "--extra"):
            extra = int(a)
        elif o in ("-d", "--download"):
            download = True
        elif o in ("-f", "--force"):
            force = True
        elif o in ("-n", "--ndays"):
            ndays = int(a)

    if vex_path_opt:
        try:
            f = open(vex_path_opt, 'r')
        except:
            "Can't open vex file"
            raise
    try:
        f = open(vex_path, 'r')
    except:
        try: 
            f = open(vex_path2, 'r')
        except:
            "Can't open vex file"
            raise
        else:
            vex_path = vex_path2

    f.close()
    calcfilepath = root + '.calc'
    calcfile = open(calcfilepath, 'w')
    
    vex2calcheader.write_header(vex_path, calcfile, obscode, job_id, increment, spectral_average, taper_function)
    vex2calcantenna.write_antenna(vex_path, calcfile, antennas)
    vex2sched.write_scan(vex_path, calcfile, offset, tail, increment, obscode)
    eop.write_eops(floor(VexSched(vex_path).startmjd() + 0.5), calcfile, extra, download, force, ndays)
    calcfooter.write_footer(obscode, calcfile)

if __name__ == '__main__':
    main()