#!/usr/bin/python

"""Date range

usage: trange [options] WHICH WHAT [WHICH WHAT]

Options:

    -e, --enum      Enumerate all UNITs in range, not just first and last.
    -f, --from      Display only FROM.
    -F, --format=FMT   Use one of formats: `words`, `lines`, `json` or
                    a UNIX date format, if FMT starts with "+" [default: words]
    -d, --debug     Turn on debugging output.
    -D, --date=DATE   Use DATE instead of reading system clock.  DATE must
                    be in ISO 8601 format
    -S, --strict    Enable strict mode, e.g. do not change "this" to "next"
    -t, --to        Display only TO.
    -u, --unit UNIT   Unit to use.  One of: `second`, `day`, `hour`,
                   `minute`, `month`, `year` or `auto`. [default: auto]
    -v, --verbose   Be verbose, e.g. warn about this vs. next.
    --version       Show version
    -h, --help      Show this screen
"""

import docopt

import imp
import sys

trange = imp.load_source('trange', '__PYLIB__/trange.py')


class UsageError(ValueError):
    pass


class Options(object):

    def __init__(self, arguments):
        self.enum = arguments['--enum']
        self.only_from = arguments['--from']
        self.only_to = arguments['--to']
        if arguments['--format'] not in ['words', 'lines', 'json']:
            raise UsageError("invalid format specified: %s"
                             % arguments['--format'])
        self.fmt = arguments['--format']
        self.date = arguments['--date']
        self.unit = arguments['--unit']
        self.debug = arguments['--debug']


class App:

    def __init__(self):
        self.arguments = docopt.docopt(__doc__, version="trange 0.1")
        self.options = Options(self.arguments)
        if self.options.debug:
            sys.stderr.write('DEBUG: options: %s\n' % self.options.__dict__)

    def run(self):
        offsets = self.arguments['WHICH']
        unitnames = self.arguments['WHAT']
        ranges = []
        while unitnames:
            ranges.append(trange.Range(offset=offsets.pop(0),
                                       unitname=unitnames.pop(0)))
        for r in ranges:
            print("%s %s" % (r.start(), r.end()))


if __name__ == '__main__':

    app = App()
    app.run()