lt

#!/usr/bin/env python
"""
CLI utility for logging the time you spend on things.
    Usage: `lt --help`
"""
from __future__ import print_function

from builtins import str
import os
import re
from datetime import date, timedelta, datetime
import click
import logtime_cli.logfile_io as logfile_io
from logtime_cli.logtime import log_time, open_logfile_for_date, continue_last_entry, recalculate
from logtime_cli.logtime_config import open_user_config, get_option
from logtime_cli.statistics import logfile_pie

def _convert_time_of_day(time_of_day):
    if time_of_day in ('A', 'a'):
        return "AM"
    if time_of_day in ('P', 'p'):
        return "PM"
    return None


def _get_time_from_argument(arg_time):
    military_time_match = re.search('^([0-1][0-9]|[2][0-3]):?([0-6][0-9])$', arg_time)
    standard_time_match = re.search('^([0][0-9]|[1][0-2]):?([0-6][0-9])([AaPp])$', arg_time)

    time_match = military_time_match or standard_time_match
    if not time_match:
        raise ValueError('"' + arg_time + '" is not a valid time')

    hours = time_match.group(1)
    minutes = time_match.group(2)
    time_string = str(hours) + str(minutes)

    if military_time_match:
        output_date = datetime.strptime(time_string, "%H%M")
        return output_date.time()

    if standard_time_match:
        meridiem = standard_time_match.group(3)
        output_date = datetime.strptime(time_string + _convert_time_of_day(meridiem), "%I%M%p")
        return output_date.time()

    return None


def _open_previous(ctx, param, value):
    del param
    if not value:
        return
    previous_date = (date.today() - timedelta(days=value))
    try:
        open_logfile_for_date(previous_date)
    except WindowsError:
        print("No logfile exists for " + str(previous_date) + ".")

    ctx.exit()


def _open_yesterday(ctx, param, value):
    if not value:
        return
    _open_previous(ctx, param, 1)


def _continue(ctx, param, value):
    del param
    if not value:
        return
    continue_last_entry()
    ctx.exit()


def _recalc(ctx, param, value):
    del param
    if not value:
        return
    recalculate()
    ctx.exit()


def _open_user_config(ctx, param, value):
    del param
    if not value:
        return
    open_user_config()
    ctx.exit()


def _open_logfile_directory(ctx, param, value):
    del param
    if not value:
        return
    log_file_directory = get_option('DEFAULT', 'logfile_directory')
    os.startfile(log_file_directory)
    ctx.exit()


def _open_pie(ctx, param, value):
    del param
    if not value:
        return

    log_data = logfile_io.load_logfile(date.today())

    logfile_pie.show_pie(log_data, date.today())

    ctx.exit()


@click.command(context_settings=dict(help_option_names=['-h', '--help']))
@click.option('--previous', '-p', type=int, callback=_open_previous, expose_value=False,
              is_eager=True, help='Open a logfile X days in the past and exit.')
@click.option('--yesterday', '-y', is_flag=True, callback=_open_yesterday, expose_value=False,
              is_eager=True, help='Open yesterdays logfile and exit. Alias for `-p 1`.')
@click.option('--continue', '-c', is_flag=True, callback=_continue, expose_value=False,
              is_eager=True,
              help='Continue the most recent entry by updating the end date and exit.')
@click.option('--recalc', '-r', is_flag=True, callback=_recalc, expose_value=False,
              is_eager=True,
              help='Recalulate each of the days time entries.')
@click.option('--config', is_flag=True, callback=_open_user_config, expose_value=False,
              is_eager=True, help='Open user config file and exit.')
@click.option('--dir', is_flag=True, callback=_open_logfile_directory, expose_value=False,
              is_eager=True, help='Open logfile directory and exit.')
@click.option('--pie', is_flag=True, callback=_open_pie, expose_value=False,
              is_eager=True, help="Show pie chart for today's time log.")
@click.argument('entry', nargs=-1)
@click.option('--begin', '-b', is_flag=True,
              help='Set the start and end time for this entry to the current time. '
              'Use `-c` to continue this entry later.')
@click.option('--start', '-s',
              help='Choose a start time for this entry. Format: `0130p`, `01:30p, `1330`, `13:30`.')
@click.option('--end', '-e',
              help='Choose an end time for this entry. Format: `0130p`, `01:30p, `1330`, `13:30`.')
def cli(entry, begin, start, end):
    """Log what you just finished doing.

    Examples:

    \b
    lt python docs
    lt john: discuss python docs

    \b
    To open today's logfile and exit, use:
    lt
    """
    if not entry:
        open_logfile_for_date(date.today(), can_create=True)
    else:
        start_time = None
        end_time = None
        if begin:
            start_time = datetime.today().time()
            end_time = datetime.today().time()
        else:
            if start:
                start_time = _get_time_from_argument(start)
            if end:
                end_time = _get_time_from_argument(end)
        log_time(' '.join(entry), start_time, end_time)

if __name__ == '__main__':
    cli() #pylint: disable=no-value-for-parameter