from datetime import datetime, timedelta
import re

class Command:
    def __init__(self, timenow, cmdline):
        self.time = timenow
        self.command = 'start'
        self.argstr = ''
        self.parseCommandLine(cmdline)

    def __str__(self):
        return "{'time' => '%s', 'command' => '%s', 'argstr' => '%s'}" % \
            (self.time, self.command, self.argstr)

    def parseCommandLine(self, cmdline):
        COMMANDS = {
                'out'       : 1,
                'report'    : 1,
                'show'      : 1,
                'fill'      : 1,
                'adjust'    : 1,
                'start'     : 1
                }
        parts = cmdline.split(None, 1)
        if len(parts) > 1:
            timespec = parts[0].strip()
            if self.parseTimeSpec(timespec):
                parts = parts[1].split(None, 1)
        if len(parts) == 1:
            command = parts[0].strip()
            rest = ''
        else:
            command, rest = parts
        if command in COMMANDS:
            self.command = command
            self.argstr = rest.strip()
        else:
            self.argstr = ' '.join([command, rest]).strip()

    def parseTimeSpec(self, timespec):
        the_time = self.time
        matched = False
        m = re.match('^(?:(\d{4})[-/])?(\d{1,2})[-/](\d{1,2}),(.+)$', timespec)
        if m is not None:
            # a date was given
            if m.group(1) is not None:
                the_time = the_time.replace(year = int(m.group(1)))
            the_time = the_time.replace(month = int(m.group(2)),
                    day = int(m.group(3)))
            timespec = m.group(4)
        m = re.match('^(\d{1,2}):?(\d{2})?(am?|pm?)?$', timespec, re.I)
        if m is not None:
            # an absolute time was given
            h = int(m.group(1))
            mins = 0 if m.group(2) is None else int(m.group(2))
            am_pm = '' if m.group(3) is None else m.group(3).lower()
            if am_pm == '' and h < 7:
                h += 12
            elif len(am_pm) >= 1 and am_pm[0] == 'p' and h < 12:
                h += 12
            elif len(am_pm) >= 1 and am_pm[0] == 'a' and h == 12:
                h = 0
            the_time = the_time.replace(hour = h, minute = mins, second = 0)
            matched = True
        else:
            m = re.match('^([-+])(\d+(?:\.\d+)?)([hms])?$', timespec, re.I)
            if m is not None:
                # a relative time was given
                plus_minus = m.group(1)
                hms = m.group(3)
                count = int(m.group(2))
                if hms == 'm':
                    seconds = count * 60
                elif hms == 's':
                    seconds = count
                else:                               # hours
                    seconds = count * 60 * 60
                delta = timedelta(seconds = seconds)
                if plus_minus == '-':
                    the_time -= delta
                else:
                    the_time += delta
                matched = True
        if matched:
            self.time = the_time
        return matched