Vice-Speaker-Rotator/vice-speaker-rotator.py

#!/usr/bin/env python3
from datetime import date,timedelta
import sys, argparse
from argparse import RawTextHelpFormatter

# text appended to the end of generated emails
email_body = """
Full speaker schedule:
https://cs.uwaterloo.ca/twiki/view/CrySP/SpeakerSchedule

Other upcoming events:
https://cs.uwaterloo.ca/twiki/view/CrySP/UpcomingEvents
"""

def str_to_date(string_date):
    return date(*[int(s) for s in string_date.split('-')])

class CryspCalendar:
    """Representation of a CrySP weekly meeting schedule for a term"""
    def __init__(self, start, end=None, weeks=None, names=[],
                 constraints=[], practice_talks=[], half_practices=[], notes=[],
                 no_repeat=False):
        self.dates = self.meeting_dates(start, end, weeks)
        self.names = names
        self.constraints = self.parse_constraints(constraints)
        self.practice_talks      = self.parse_practice_talks(practice_talks)
        self.practice_talks.update(self.parse_practice_talks(half_practices,
                                                             half=True))
        self.notes      = self.parse_notes(notes)
        self.notes.update(self.parse_notes(practice_talks))
        self.notes.update(self.parse_notes(half_practices))
        self.verify_constraints()
        self.no_repeat = no_repeat

    def meeting_dates(self, start, end=None, weeks=None):
        first_meeting = str_to_date(start)
        last_meeting = None
        if end:
            last_meeting = str_to_date(end)
        if weeks:
            last_meeting = max(first_meeting + timedelta(weeks=weeks),
                               last_meeting)
        ret = []
        next_meeting = first_meeting
        one_week = timedelta(weeks=1)
        while next_meeting <= last_meeting:
            ret.append(next_meeting)
            next_meeting += one_week
        return ret

    def parse_constraints(self, constraints):
        constraint_dict = {}
        for constraint in constraints:
            name      = constraint[0]
            date_strs = constraint[1:]
            dates     = []
            for date_str in date_strs:
                dates.append(str_to_date(date_str))
                constraint_dict[name] = dates
        return constraint_dict

    def parse_practice_talks(self, practice, half=False):
        practice_dict = {}
        for talk in practice:
            name = talk[0]
            day  = str_to_date(talk[1])
            if day in practice_dict:
                assert half,\
                    'conflicting talks: %s and %s on %s' %\
                    (practice_dict[day][0], name, day)
                practice_dict[day].append(name)
            elif half:
                practice_dict[day] = [name,]
            else:
                practice_dict[day] = [name, '']
        return practice_dict

    def parse_notes(self, notes):
        notes_dict = {}
        for note in notes:
            day     = str_to_date(note[1])
            message = note[2]
            assert day not in notes_dict or notes_dict[day] == message,\
                'conflicting notes: "%s" and "%s" on %s' %\
                (notes_dict[day], message, note[1])
            notes_dict[day] = message
        return notes_dict

    def verify_constraints(self):
        for name in self.constraints:
            for day in self.constraints[name]:
                assert day in self.dates,\
                    'constraint added for %s on %s, which is not a meeting date' %\
                    (name, day)
        for day in self.practice_talks:
            assert day in self.dates,\
                'talk by %s designated on %s, which is not a meeting date' %\
                (self.practice_talks[day][0], day)
        for day in self.notes:
            assert day in self.dates,\
                'note "%s" designated on %s, which is not a meeting date' %\
                (self.notes[day], day)

    def pop_name(self, day, names, i):
        """Pops the name of the next available on day from the names stack,
           where 'i' is which speaker they would be for that day (0 or 1).
           Returns None if no speakers are left in the given names stack."""
        name = None
        if day in self.practice_talks:
            if i < len(self.practice_talks[day]):
                name = self.practice_talks[day][i]
        if name is None:
            constrained_names = (name for name in names \
                                 if name not in self.constraints \
                                 or day  not in self.constraints[name])
            name = next(constrained_names, None)
        if name and name in names:
            names.remove(name)
        return name

    def next_speaker(self, day, names, i):
        """Wrapper for pop_name() that repopulates names stack if needed."""
        name = self.pop_name(day, names, i)
        if name or self.no_repeat:
            return name
        names.extend(self.names)
        return self.pop_name(day, names, i)

    def date_to_speakers(self, day, names):
        speaker1 = self.next_speaker(day, names, 0)
        speaker2 = self.next_speaker(day, names, 1)
        note = self.notes.get(day, '')
        return speaker1, speaker2, note

    def table(self):
        """Returns a string containing a twiki table."""
        table = '| *Date* | *Speakers* | *Notes* |\n'
        names = self.names.copy()
        for day in self.dates:
            table += day.strftime('| %b %e |')
            speaker1, speaker2, note = self.date_to_speakers(day, names)
            if speaker1:
                table += ' ' + speaker1
            if speaker2:
                table += ', ' + speaker2
            table += ' | ' + note + ' |\n'
        return table

    def email(self, weeks=2, today=date.today()):
        """Returns a string for emailing to the lab who is speaking next"""
        emailstr = ''
        names = self.names.copy()
        i = 0
        for day in self.dates:
            if day <= today:
                self.date_to_speakers(day, names)
                continue
            i += 1
            if i > weeks:
                break
            speaker1, speaker2, note = self.date_to_speakers(day, names)
            emailstr += day.strftime('%b %e: ')
            if speaker1:
                emailstr += speaker1
                if speaker2:
                    emailstr +=  ', ' + speaker2
                if note != '':
                    emailstr += ' (' + note + ')'
            else:
                emailstr += note
            emailstr += '\n'
        emailstr += email_body
        return emailstr

def parse_constraintsfile(filename):
    with open(filename, 'r') as f:
        tweaks = {'c': [], 'p': [], 'h': [], 'n': []}
        for line in f:
            l = [x.strip() for x in line.rstrip().split(',')]
            tweaks[l[0]].append(l[1:])
        return tweaks['c'], tweaks['p'], tweaks['h'], tweaks['n']

def make_parser():
    parser = argparse.ArgumentParser(description =
        'Print a speaker schedule for the CrySP weekly meetings.',
        formatter_class=RawTextHelpFormatter)
    parser.add_argument('-s', '--start',
                        metavar = 'DATE', required = True,
                        help =
                        'date of the first meeting in ISO format\n' +\
                        '(yyyy-mm-dd)')
    parser.add_argument('-e', '--end', metavar = 'DATE',
                        help =
                        'last date to schedule a meeting on or before\n' +\
                        '(if -w also specified, uses whatever is shortest)')
    parser.add_argument('-w', '--weeks', type=int,
                        help =
                        'number of weeks to schedule for\n' +\
                        '(if -e also specified, uses whatever is shortest)')

    group = parser.add_mutually_exclusive_group()
    group.add_argument('-n', '--names',
                       nargs = '+', default = [], metavar = 'NAME',
                       help =
                       'names to schedule in their speaking order')
    group.add_argument('-f', '--namesfile',
                       metavar = 'FILE',
                       help =
                       'path of a file that contains a comma-seperated\n' +\
                       ' list of names to schedule in their speaking order')

    parser.add_argument('-c', '--constraintsfile',
                        metavar = 'FILE',
                        help =
                        'Provide constraints, practice talks, and notes\n' +\
                        'via supplied csv file. The CSV can contain the\n' +\
                        'following lines:\n' +\
                        'constraints - dates where someone cannot speak:\n' +\
                        '"c,[name],[date1],[date2],[...]"\n' +\
                        'notes - goes in the notes column for that date:\n' +\
                        '"n,[date],[note]"\n' +\
                        'practice talks - dates where something other than\n' +\
                        'the usual CrySP meeting talks is happening:\n' +\
                        '"p,[name],[date],[note (e.g., "practice talk")]"\n' +\
                        'half-slot - a rare case where someone/thing needs\n' +\
                        'only one of the speaker slots on this date:\n' +\
                        '"h,[name],[date],[note]"\n')

    parser.add_argument('-r', '--no-repeat',
                        action = 'store_true',
                        help =
                        'disables repeating the list of names')
    parser.add_argument('-E', '--email',
                        nargs = '?', const = 2, default = False,
                        metavar = 'WEEKS',
                        help =
                        'print an email for notifying who is speaking\n' +\
                        'the next two (or specified) weeks')
    return parser

def main(argv=None):
    if argv is None:
        argv = sys.argv
    parser = make_parser()
    args = parser.parse_args()

    if not args.end and not args.weeks:
        parser.error('requires -w/--weeks or -e/--end')

    if args.namesfile:
        with open(args.namesfile, 'r') as f:
            names = [x.strip() for x in f.read().split(',')]
    else:
        names = args.names

    if args.constraintsfile:
        constraints, practice, halves, notes = \
            parse_constraintsfile(args.constraintsfile)
        cal = CryspCalendar(args.start, args.end, args.weeks, names,
                            constraints, practice, halves, notes,
                            args.no_repeat)
    else:
        cal = CryspCalendar(args.start, args.end, args.weeks, names,
                            no_repeat=args.no_repeat)

    print(cal.table() if not args.email else cal.email(int(args.email)))
    return 0;

if __name__ == '__main__':
    sys.exit(main())