#!/usr/bin/env python3

# http://inamidst.com/saxo/
# Created by Sean B. Palmer

import re
import time
import saxo

clock_dict_scales = {
    365.25 * 24 * 3600: ("years", "year", "yrs", "y"),
    29.53059 * 24 * 3600: ("months", "month", "mo"),
    7 * 24 * 3600: ("weeks", "week", "wks", "wk", "w"),
    24 * 3600: ("days", "day", "d"),
    3600: ("hours", "hour", "hrs", "hr", "h"),
    60: ("minutes", "minute", "mins", "min", "m"),
    1: ("seconds", "second", "secs", "sec", "s")
}

clock_dict_scaling = {}
for period, names in clock_dict_scales.items():
    for name in names:
        clock_dict_scaling[name] = period

clock_regex_period = re.compile(r"(?i)([0-9]+(?:\.[0-9]+)?) *([a-z]+)")

def period_seconds(match):
    number, unit = match.groups()
    number = float(number)
    unit = unit.lower()

    if not unit in clock_dict_scaling:
        raise ValueError("Invalid period unit: %s" % unit)

    scale = clock_dict_scaling[unit]
    seconds = number * scale

    return number, unit, scale, seconds

def periods_seconds(text):
    seconds = 0
    periods = 0
    durations = []
    remainder = text

    while True:
        remainder = remainder.lstrip()
        match = clock_regex_period.match(remainder)
        if not match:
            break

        period = match.group(0)
        try:  _, _, _, p_seconds = period_seconds(match)
        except ValueError as err:
            break

        seconds += p_seconds
        periods += 1
        durations.append(p_seconds)
        remainder = remainder[len(period):]

    return int(seconds), remainder

def parse_periods(text):
    basetime = int(time.time())
    seconds, message = periods_seconds(text)
    return seconds, basetime + seconds, message

@saxo.pipe
def main(arg):
    if not arg:
        return "Schedule a reminder"

    seconds, unixtime, message = parse_periods(arg)
    if not seconds:
        return "Couldn't understand your duration. Use units?"

    nick = saxo.env("nick")
    sender = saxo.env("sender")

    if not (nick or sender):
        return "Sorry, couldn't set a reminder!"

    if message:
        message = nick + ": " + message
    else:
        message = nick + "!"

    args = (unixtime, "msg", (sender, message))
    saxo.client("schedule", *args)

    when = time.strftime("%d %b %Y %H:%M:%S UTC", time.gmtime(unixtime))
    return "%s: Will remind at %s" % (nick, when)