#!/usr/bin/env python
# -*- mode: python; coding: utf-8 -*
# Copyright (c) 2018 Radio Astronomy Software Group
# Licensed under the 2-clause BSD License

"""
A command-line script for converting
any pyuvdata compatible file to UVFITS format
"""

from __future__ import absolute_import, division, print_function

import argparse
import sys
import os
import pyuvdata
from astropy.time import Time

# setup argparse
a = argparse.ArgumentParser(description="A command-line script for converting file(s) to UVFITS format.")
a.add_argument("files", type=str, nargs='*', help="pyuvdata-compatible file(s) to convert to uvfits.")
a.add_argument("--output_filename", type=str, default=None, help="Filepath of output file. Default is input with suffix replaced by .uvfits")
a.add_argument("--phase_time", type=float, default=None, help="Julian Date to phase data to. Default is the first integration of the file.")
a.add_argument("--overwrite", default=False, action='store_true', help="overwrite output file if it already exists.")
a.add_argument("--verbose", default=False, action='store_true', help="report feedback to stdout.")


# get args
args = a.parse_args()
history = ' '.join(sys.argv)

# iterate over files
for filename in args.files:

    # check output
    if args.output_filename is None:
        splitext = os.path.splitext(filename)[1]
        if splitext[1] == '.uvh5':
            outfilename = splitext[0] + '.uvfits'
        elif splitext[1] in ['.ms', '.MS']:
            outfilename = splitext[0] + '.uvfits'
        elif splitext[1] == '.sav':
            outfilename = splitext[0] + '.uvfits'
        else:
            outfilename = filename + '.uvfits'
    else:
        outfilename = args.output_filename
    if os.path.exists(outfilename) and args.overwrite is False:
        print("{} exists, not overwriting...".format(outfilename))
        continue

    # read in file
    UV = pyuvdata.UVData()
    UV.read(filename)

    if UV.phase_type == 'drift':
        # phase data
        if args.phase_time is not None:
            UV.phase_to_time(Time(args.phase_time, format='jd', scale='utc'))
            if args.verbose:
                print("phasing {} to time {}".format(filename, args.phase_time))

        else:
            UV.phase_to_time(Time(UV.time_array[0], format='jd', scale='utc'))
            if args.verbose:
                print("phasing {} to time {}".format(filename, UV.time_array[0]))

    # write data
    UV.history += history
    if args.verbose:
        print("saving {}".format(outfilename))
    UV.write_uvfits(outfilename, spoof_nonessential=True)