Limnoria/src/schedule.py

#!/usr/bin/env python

###
# Copyright (c) 2002, Jeremiah Fincher
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#     this list of conditions, and the following disclaimer.
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###

"""
Schedule plugin with a subclass of drivers.IrcDriver in order to be run as a
Supybot driver.
"""

__revision__ = "$Id$"

import fix

import time
import heapq

import drivers

class mytuple(tuple):
    def __cmp__(self, other):
        return cmp(self[0], other[0])
    def __le__(self, other):
        return self[0] <= other[0]
    def __lt__(self, other):
        return self[0] < other[0]
    def __gt__(self, other):
        return self[0] > other[0]
    def __ge__(self, other):
        return self[0] >= other[0]

class Schedule(drivers.IrcDriver):
    """An IrcDriver to handling scheduling of events.

    Events, in this case, are functions accepting no arguments.
    """
    def __init__(self):
        drivers.IrcDriver.__init__(self)
        self.schedule = []
        self.events = {}
        self.counter = 0

    def addEvent(self, f, t, name=None):
        """Schedules an event f to run at time t.

        name must be hashable and not an int.
        """
        if name is None:
            name = self.counter
            self.counter += 1
        elif isinstance(name, int):
            raise ValueError, 'int names are reserved for the scheduler.'
        assert name not in self.events
        self.events[name] = f
        heapq.heappush(self.schedule, mytuple((t, name)))

    def removeEvent(self, name):
        """Removes the event with the given name from the schedule."""
        del self.events[name]
        heapq.heappop(self.schedule)
        self.schedule = [(t, n) for (t, n) in self.schedule if n != name]

    def addPeriodicEvent(self, f, t, name=None):
        """Adds a periodic event that is called every t seconds."""
        def wrapper():
            f()
            self.addEvent(wrapper, time.time() + t, name)
        wrapper()

    removePeriodicEvent = removeEvent

    def run(self):
        while self.schedule and self.schedule[0][0] < time.time():
            (t, name) = heapq.heappop(self.schedule)
            f = self.events[name]
            del self.events[name]
            f()

try:
    ignore(schedule)
except NameError:
    schedule = Schedule()

addEvent = schedule.addEvent
removeEvent = schedule.removeEvent
addPeriodicEvent = schedule.addPeriodicEvent
removePeriodicEvent = removeEvent
run = schedule.run
# vim:set shiftwidth=4 tabstop=8 expandtab textwidth=78: