Source code for vdat.config.entry_point

"""Implementation of the ``vdat_config`` entry point"""
from __future__ import (absolute_import, division, print_function,
                        unicode_literals)

import argparse
from copy import copy as ccopy
import os

import pkg_resources
import six

try:
    input = raw_input
except NameError:
    pass

# The ``CONFIG_FILES`` are scanned to look for some placeholder to replace at
# run time
COPY_FILES = ["vdat_setting.cfg", "tabs.yml", 'fplane.txt',
              'vdat_commands.yml', 'buttons.yml']
"""Files copied from the package"""
COPY_DIR = ["extra_files"]
"""The files in the following subdirectories are copied too"""


# command line code to get the configuration files
def main(argv=None):
    """Main function of the implementation of the ``vdat_config`` executable

    Parameters
    ----------
    argv : list
        command line, if None taken from ``sys.argv``
    """

    args = parse(argv=argv)

    if args.subparser_name == 'copy':
        copy(args)


def parse(argv=None):
    """Create the parser and parse the command line arguments

    Parameters
    ----------
    argv : list
        command line, if None taken from ``sys.argv``

    Returns
    -------
    Namespace
        parsed command line
    """

    parser = argparse.ArgumentParser(description="""Deal with the vdat
                                     configuration files""")

    subparser = parser.add_subparsers(title='Subcommands',
                                      dest='subparser_name',
                                      description="""Type '%(prog)s cmd -h' for
                                      detailed information about the
                                      subcommands""")

    description = ("Copy the files '{}' into the given"
                   " directory".format("', '".join(COPY_FILES)))
    copy = subparser.add_parser('copy', description=description,
                                help='Copy the configuration files')

    copy.add_argument('-t', '--to-dir', default='.',
                      help="Directory where to copy the data")
    copy.add_argument('-f', '--force', action='store_true',
                      help="Force overwriting existing configuration files. If"
                      " this option is used, all local modifications will be"
                      " lost")

    return parser.parse_args(args=argv)


def _encode(str_):
    """In python 3 encodes the string into bytes, in python 2 returns the
    input

    Parameters
    ----------
    str_ : string type
        string to encode

    Returns
    bytes
    """
    if six.PY3 and isinstance(str_, six.string_types):
        return str_.encode()
    else:
        return str_


def copy(args):
    """Copy the configuration files

    Parameters
    ----------
    args : Namespace
        arguments to make the copy run
    """
    written_files = []
    _COPY_FILES = ccopy(COPY_FILES)

    # loop the directories, create them on the receiver end if necessary and
    # add the contained files to the list of the ones to copy
    for dir_ in COPY_DIR:
        try:
            os.mkdir(os.path.join(args.to_dir, dir_))
        except OSError:
            pass
        for fname in pkg_resources.resource_listdir(__name__, dir_):
            _COPY_FILES.append(os.path.join(dir_, fname))

    for cf in _COPY_FILES:
        ofile = os.path.join(args.to_dir, cf)
        if os.path.exists(ofile) and not args.force:
            overwrite = False
            msg = "Do you want to overwrite file '{}' (y/[n])?".format(cf)
            while True:
                try:
                    msg
                    answer = input(msg)
                    if not answer:
                        answer = 'n'
                    if answer.lower() == 'y':
                        overwrite = True
                        break
                    elif answer.lower() == 'n':
                        break
                    else:
                        continue
                except EOFError:
                    break
            if not overwrite:
                continue
        ifile = pkg_resources.resource_string(__name__, cf)
        with open(ofile, 'wb') as of:
            ifile = ifile.replace(_encode('<++>CONFIG_DIR<++>'),
                                  _encode(os.path.abspath(args.to_dir)))
            of.write(ifile)
        written_files.append(cf)

    if written_files:
        msg = "File(s) '{}' copied to directory '{}'"
        print(msg.format("', '".join(written_files), args.to_dir))
    else:
        msg = "No file copied to directory '{}'"
        print(msg.format(args.to_dir))


if __name__ == '__main__':
    main()