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

from __future__ import absolute_import, division, print_function

import argparse
from pyuvdata import UVData, UVBeam, UVCal
import os

# setup argparse
a = argparse.ArgumentParser(description=("Inspect attributes of pyuvdata objects.\n"
                                         "Example: pyuvdata_inspect.py -a=ant_array.shape,"
                                         "Ntimes zen.xx.HH.omni.calfits zen.yy.HH.uvc"),
                            formatter_class=argparse.RawDescriptionHelpFormatter)

a.add_argument("-a", "--attrs", dest="attrs", type=str, default='',
               help="attribute(s) of object to print. Ex: ant_array.shape,Ntimes")
a.add_argument("-v", "--verbose", action='store_true', default=False,
               help="Send feedback to stdout.")
a.add_argument("-i", "--interactive", action='store_true', default=False,
               help="Exit into a python interpretor with objects in memory as 'uv'.")
a.add_argument("files", metavar="files", type=str, nargs='*', default=[],
               help="pyuvdata object files to run on")

# parse arguments
args = a.parse_args()

# check for empty attributes
if len(args.attrs) == 0 and args.interactive is False:
    raise Exception("no attributes fed...")
if len(args.files) == 0:
    raise Exception("no files fed...")

# pack data objects, their names, and read functions
objs = [UVData, UVCal, UVBeam]
ob_names = ['UVData', 'UVCal', 'UVBeam']
ob_reads = [['read', 'read_miriad', 'read_fhd', 'read_ms', 'read_uvfits', 'read_uvh5'],
            ['read_calfits', 'read_fhd_cal'],
            ['read_beamfits', 'read_cst_beam']]

# iterate through files
Nfiles = len(args.files)
uv = []
exit_clean = True
for i, f in enumerate(args.files):
    # check file exists
    if os.path.exists(f) is False:
        print("{0} doesn't exist".format(f))
        if i == (Nfiles - 1):
            exit(1)
        else:
            continue

    opened = False
    filetype = None
    # try to open object
    for j, ob in enumerate(objs):
        for k, r in enumerate(ob_reads[j]):
            try:
                # instantiate data class and try to read file
                UV = ob()
                getattr(UV, r)(f)
                opened = True
                uv.append(UV)
                filetype = r.split('_')[-1]
                if args.verbose is True:
                    print("opened {0} as a {1} file with the {2} pyuvdata object".format(f, filetype, ob_names[j]))
            except (IOError, KeyError, ValueError, RuntimeError):
                continue
            # exit loop if opened
            if opened is True:
                break
        if opened is True:
            break

    # if object isn't opened continue
    if opened is False:
        print("couldn't open {0} with any of the pyuvdata objects {1}".format(f, ob_names))
        continue

    # print out desired attribute(s) of data object
    attrs = [x.split('.') for x in args.attrs.split(',')]
    for j, attr in enumerate(attrs):
        # try to get attribute
        try:
            Nnest = len(attr)
            this_attr = getattr(UV, attr[0])
            for k in range(Nnest - 1):
                this_attr = getattr(this_attr, attr[k + 1])
            # print to stdout
            print("{0} of {1} is: {2}".format('.'.join(attr), f, this_attr))
            exit_clean = True
        except AttributeError:
            print("Couldn't access '{0}' from {1}".format('.'.join(attr), f))
            exit_clean = False

if args.interactive:
    if len(uv) == 1:
        uv = uv[0]
    try:
        from IPython import embed
        embed()
    except ImportError:
        import code
        code.interact(local=dict(globals(), **locals()))

else:
    if exit_clean is True:
        exit(0)
    else:
        exit(1)