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

"""Convert 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)