paul@213 | 1 | #!/usr/bin/env python |
paul@213 | 2 | |
paul@213 | 3 | """ |
paul@213 | 4 | Interpretation of vCalendar content. |
paul@213 | 5 | |
paul@213 | 6 | Copyright (C) 2014, 2015 Paul Boddie <paul@boddie.org.uk> |
paul@213 | 7 | |
paul@213 | 8 | This program is free software; you can redistribute it and/or modify it under |
paul@213 | 9 | the terms of the GNU General Public License as published by the Free Software |
paul@213 | 10 | Foundation; either version 3 of the License, or (at your option) any later |
paul@213 | 11 | version. |
paul@213 | 12 | |
paul@213 | 13 | This program is distributed in the hope that it will be useful, but WITHOUT |
paul@213 | 14 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
paul@213 | 15 | FOR A PARTICULAR PURPOSE. See the GNU General Public License for more |
paul@213 | 16 | details. |
paul@213 | 17 | |
paul@213 | 18 | You should have received a copy of the GNU General Public License along with |
paul@213 | 19 | this program. If not, see <http://www.gnu.org/licenses/>. |
paul@213 | 20 | """ |
paul@213 | 21 | |
paul@424 | 22 | from bisect import bisect_left |
paul@256 | 23 | from datetime import datetime, timedelta |
paul@213 | 24 | from email.mime.text import MIMEText |
paul@392 | 25 | from imiptools.dates import format_datetime, get_datetime, get_duration, \ |
paul@392 | 26 | get_freebusy_period, get_period, to_timezone, \ |
paul@392 | 27 | to_utc_datetime |
paul@327 | 28 | from imiptools.period import period_overlaps |
paul@316 | 29 | from pytz import timezone |
paul@213 | 30 | from vCalendar import iterwrite, parse, ParseError, to_dict, to_node |
paul@256 | 31 | from vRecurrence import get_parameters, get_rule |
paul@213 | 32 | import email.utils |
paul@213 | 33 | |
paul@213 | 34 | try: |
paul@213 | 35 | from cStringIO import StringIO |
paul@213 | 36 | except ImportError: |
paul@213 | 37 | from StringIO import StringIO |
paul@213 | 38 | |
paul@213 | 39 | class Object: |
paul@213 | 40 | |
paul@213 | 41 | "Access to calendar structures." |
paul@213 | 42 | |
paul@213 | 43 | def __init__(self, fragment): |
paul@213 | 44 | self.objtype, (self.details, self.attr) = fragment.items()[0] |
paul@213 | 45 | |
paul@213 | 46 | def get_items(self, name, all=True): |
paul@213 | 47 | return get_items(self.details, name, all) |
paul@213 | 48 | |
paul@213 | 49 | def get_item(self, name): |
paul@213 | 50 | return get_item(self.details, name) |
paul@213 | 51 | |
paul@213 | 52 | def get_value_map(self, name): |
paul@213 | 53 | return get_value_map(self.details, name) |
paul@213 | 54 | |
paul@213 | 55 | def get_values(self, name, all=True): |
paul@213 | 56 | return get_values(self.details, name, all) |
paul@213 | 57 | |
paul@213 | 58 | def get_value(self, name): |
paul@213 | 59 | return get_value(self.details, name) |
paul@213 | 60 | |
paul@213 | 61 | def get_utc_datetime(self, name): |
paul@213 | 62 | return get_utc_datetime(self.details, name) |
paul@213 | 63 | |
paul@417 | 64 | def get_date_values(self, name, tzid=None): |
paul@417 | 65 | items = get_date_value_items(self.details, name, tzid) |
paul@389 | 66 | return items and [value for value, attr in items] |
paul@352 | 67 | |
paul@417 | 68 | def get_date_value_items(self, name, tzid=None): |
paul@417 | 69 | return get_date_value_items(self.details, name, tzid) |
paul@352 | 70 | |
paul@318 | 71 | def get_datetime(self, name): |
paul@318 | 72 | dt, attr = get_datetime_item(self.details, name) |
paul@318 | 73 | return dt |
paul@318 | 74 | |
paul@289 | 75 | def get_datetime_item(self, name): |
paul@289 | 76 | return get_datetime_item(self.details, name) |
paul@289 | 77 | |
paul@392 | 78 | def get_duration(self, name): |
paul@392 | 79 | return get_duration(self.get_value(name)) |
paul@392 | 80 | |
paul@213 | 81 | def to_node(self): |
paul@213 | 82 | return to_node({self.objtype : [(self.details, self.attr)]}) |
paul@213 | 83 | |
paul@213 | 84 | def to_part(self, method): |
paul@213 | 85 | return to_part(method, [self.to_node()]) |
paul@213 | 86 | |
paul@213 | 87 | # Direct access to the structure. |
paul@213 | 88 | |
paul@392 | 89 | def has_key(self, name): |
paul@392 | 90 | return self.details.has_key(name) |
paul@392 | 91 | |
paul@213 | 92 | def __getitem__(self, name): |
paul@213 | 93 | return self.details[name] |
paul@213 | 94 | |
paul@213 | 95 | def __setitem__(self, name, value): |
paul@213 | 96 | self.details[name] = value |
paul@213 | 97 | |
paul@213 | 98 | def __delitem__(self, name): |
paul@213 | 99 | del self.details[name] |
paul@213 | 100 | |
paul@256 | 101 | # Computed results. |
paul@256 | 102 | |
paul@360 | 103 | def has_recurrence(self, tzid, recurrence): |
paul@424 | 104 | recurrences = [start for start, end in get_periods(self, tzid, recurrence, inclusive=True)] |
paul@360 | 105 | return recurrence in recurrences |
paul@256 | 106 | |
paul@424 | 107 | def get_periods(self, tzid, end, origin=False): |
paul@424 | 108 | return get_periods(self, tzid, end, origin=origin) |
paul@360 | 109 | |
paul@424 | 110 | def get_periods_for_freebusy(self, tzid, end, origin=False): |
paul@424 | 111 | periods = self.get_periods(tzid, end, origin) |
paul@291 | 112 | return get_periods_for_freebusy(self, periods, tzid) |
paul@291 | 113 | |
paul@422 | 114 | def get_tzid(self): |
paul@422 | 115 | dtstart, dtstart_attr = self.get_datetime_item("DTSTART") |
paul@422 | 116 | dtend, dtend_attr = self.get_datetime_item("DTEND") |
paul@422 | 117 | return get_tzid(dtstart_attr, dtend_attr) |
paul@422 | 118 | |
paul@213 | 119 | # Construction and serialisation. |
paul@213 | 120 | |
paul@213 | 121 | def make_calendar(nodes, method=None): |
paul@213 | 122 | |
paul@213 | 123 | """ |
paul@213 | 124 | Return a complete calendar node wrapping the given 'nodes' and employing the |
paul@213 | 125 | given 'method', if indicated. |
paul@213 | 126 | """ |
paul@213 | 127 | |
paul@213 | 128 | return ("VCALENDAR", {}, |
paul@213 | 129 | (method and [("METHOD", {}, method)] or []) + |
paul@213 | 130 | [("VERSION", {}, "2.0")] + |
paul@213 | 131 | nodes |
paul@213 | 132 | ) |
paul@213 | 133 | |
paul@327 | 134 | def make_freebusy(freebusy, uid, organiser, organiser_attr=None, attendee=None, |
paul@327 | 135 | attendee_attr=None, dtstart=None, dtend=None): |
paul@222 | 136 | |
paul@222 | 137 | """ |
paul@222 | 138 | Return a calendar node defining the free/busy details described in the given |
paul@292 | 139 | 'freebusy' list, employing the given 'uid', for the given 'organiser' and |
paul@292 | 140 | optional 'organiser_attr', with the optional 'attendee' providing recipient |
paul@292 | 141 | details together with the optional 'attendee_attr'. |
paul@327 | 142 | |
paul@327 | 143 | The result will be constrained to the 'dtstart' and 'dtend' period if these |
paul@327 | 144 | parameters are given. |
paul@222 | 145 | """ |
paul@222 | 146 | |
paul@222 | 147 | record = [] |
paul@222 | 148 | rwrite = record.append |
paul@222 | 149 | |
paul@292 | 150 | rwrite(("ORGANIZER", organiser_attr or {}, organiser)) |
paul@222 | 151 | |
paul@222 | 152 | if attendee: |
paul@292 | 153 | rwrite(("ATTENDEE", attendee_attr or {}, attendee)) |
paul@222 | 154 | |
paul@222 | 155 | rwrite(("UID", {}, uid)) |
paul@222 | 156 | |
paul@222 | 157 | if freebusy: |
paul@327 | 158 | |
paul@327 | 159 | # Get a constrained view if start and end limits are specified. |
paul@327 | 160 | |
paul@327 | 161 | periods = dtstart and dtend and period_overlaps(freebusy, (dtstart, dtend), True) or freebusy |
paul@327 | 162 | |
paul@327 | 163 | # Write the limits of the resource. |
paul@327 | 164 | |
paul@327 | 165 | rwrite(("DTSTART", {"VALUE" : "DATE-TIME"}, periods[0][0])) |
paul@327 | 166 | rwrite(("DTEND", {"VALUE" : "DATE-TIME"}, periods[-1][1])) |
paul@327 | 167 | |
paul@395 | 168 | for start, end, uid, transp, recurrenceid, summary, organiser in periods: |
paul@222 | 169 | if transp == "OPAQUE": |
paul@222 | 170 | rwrite(("FREEBUSY", {"FBTYPE" : "BUSY"}, "/".join([start, end]))) |
paul@222 | 171 | |
paul@222 | 172 | return ("VFREEBUSY", {}, record) |
paul@222 | 173 | |
paul@213 | 174 | def parse_object(f, encoding, objtype=None): |
paul@213 | 175 | |
paul@213 | 176 | """ |
paul@213 | 177 | Parse the iTIP content from 'f' having the given 'encoding'. If 'objtype' is |
paul@213 | 178 | given, only objects of that type will be returned. Otherwise, the root of |
paul@213 | 179 | the content will be returned as a dictionary with a single key indicating |
paul@213 | 180 | the object type. |
paul@213 | 181 | |
paul@213 | 182 | Return None if the content was not readable or suitable. |
paul@213 | 183 | """ |
paul@213 | 184 | |
paul@213 | 185 | try: |
paul@213 | 186 | try: |
paul@213 | 187 | doctype, attrs, elements = obj = parse(f, encoding=encoding) |
paul@213 | 188 | if objtype and doctype == objtype: |
paul@213 | 189 | return to_dict(obj)[objtype][0] |
paul@213 | 190 | elif not objtype: |
paul@213 | 191 | return to_dict(obj) |
paul@213 | 192 | finally: |
paul@213 | 193 | f.close() |
paul@213 | 194 | |
paul@213 | 195 | # NOTE: Handle parse errors properly. |
paul@213 | 196 | |
paul@213 | 197 | except (ParseError, ValueError): |
paul@213 | 198 | pass |
paul@213 | 199 | |
paul@213 | 200 | return None |
paul@213 | 201 | |
paul@213 | 202 | def to_part(method, calendar): |
paul@213 | 203 | |
paul@213 | 204 | """ |
paul@213 | 205 | Write using the given 'method', the 'calendar' details to a MIME |
paul@213 | 206 | text/calendar part. |
paul@213 | 207 | """ |
paul@213 | 208 | |
paul@213 | 209 | encoding = "utf-8" |
paul@213 | 210 | out = StringIO() |
paul@213 | 211 | try: |
paul@213 | 212 | to_stream(out, make_calendar(calendar, method), encoding) |
paul@213 | 213 | part = MIMEText(out.getvalue(), "calendar", encoding) |
paul@213 | 214 | part.set_param("method", method) |
paul@213 | 215 | return part |
paul@213 | 216 | |
paul@213 | 217 | finally: |
paul@213 | 218 | out.close() |
paul@213 | 219 | |
paul@213 | 220 | def to_stream(out, fragment, encoding="utf-8"): |
paul@213 | 221 | iterwrite(out, encoding=encoding).append(fragment) |
paul@213 | 222 | |
paul@213 | 223 | # Structure access functions. |
paul@213 | 224 | |
paul@213 | 225 | def get_items(d, name, all=True): |
paul@213 | 226 | |
paul@213 | 227 | """ |
paul@213 | 228 | Get all items from 'd' for the given 'name', returning single items if |
paul@213 | 229 | 'all' is specified and set to a false value and if only one value is |
paul@213 | 230 | present for the name. Return None if no items are found for the name or if |
paul@213 | 231 | many items are found but 'all' is set to a false value. |
paul@213 | 232 | """ |
paul@213 | 233 | |
paul@213 | 234 | if d.has_key(name): |
paul@213 | 235 | values = d[name] |
paul@213 | 236 | if all: |
paul@213 | 237 | return values |
paul@213 | 238 | elif len(values) == 1: |
paul@213 | 239 | return values[0] |
paul@213 | 240 | else: |
paul@213 | 241 | return None |
paul@213 | 242 | else: |
paul@213 | 243 | return None |
paul@213 | 244 | |
paul@213 | 245 | def get_item(d, name): |
paul@213 | 246 | return get_items(d, name, False) |
paul@213 | 247 | |
paul@213 | 248 | def get_value_map(d, name): |
paul@213 | 249 | |
paul@213 | 250 | """ |
paul@213 | 251 | Return a dictionary for all items in 'd' having the given 'name'. The |
paul@213 | 252 | dictionary will map values for the name to any attributes or qualifiers |
paul@213 | 253 | that may have been present. |
paul@213 | 254 | """ |
paul@213 | 255 | |
paul@213 | 256 | items = get_items(d, name) |
paul@213 | 257 | if items: |
paul@213 | 258 | return dict(items) |
paul@213 | 259 | else: |
paul@213 | 260 | return {} |
paul@213 | 261 | |
paul@213 | 262 | def get_values(d, name, all=True): |
paul@213 | 263 | if d.has_key(name): |
paul@213 | 264 | values = d[name] |
paul@213 | 265 | if not all and len(values) == 1: |
paul@213 | 266 | return values[0][0] |
paul@213 | 267 | else: |
paul@213 | 268 | return map(lambda x: x[0], values) |
paul@213 | 269 | else: |
paul@213 | 270 | return None |
paul@213 | 271 | |
paul@213 | 272 | def get_value(d, name): |
paul@213 | 273 | return get_values(d, name, False) |
paul@213 | 274 | |
paul@417 | 275 | def get_date_value_items(d, name, tzid=None): |
paul@352 | 276 | |
paul@352 | 277 | """ |
paul@389 | 278 | Obtain items from 'd' having the given 'name', where a single item yields |
paul@389 | 279 | potentially many values. Return a list of tuples of the form (value, |
paul@389 | 280 | attributes) where the attributes have been given for the property in 'd'. |
paul@352 | 281 | """ |
paul@352 | 282 | |
paul@403 | 283 | items = get_items(d, name) |
paul@403 | 284 | if items: |
paul@403 | 285 | all_items = [] |
paul@403 | 286 | for item in items: |
paul@403 | 287 | values, attr = item |
paul@417 | 288 | if not attr.has_key("TZID") and tzid: |
paul@417 | 289 | attr["TZID"] = tzid |
paul@403 | 290 | if not isinstance(values, list): |
paul@403 | 291 | values = [values] |
paul@403 | 292 | for value in values: |
paul@403 | 293 | all_items.append((get_datetime(value, attr) or get_period(value, attr), attr)) |
paul@403 | 294 | return all_items |
paul@352 | 295 | else: |
paul@352 | 296 | return None |
paul@352 | 297 | |
paul@213 | 298 | def get_utc_datetime(d, name): |
paul@348 | 299 | t = get_datetime_item(d, name) |
paul@348 | 300 | if not t: |
paul@348 | 301 | return None |
paul@348 | 302 | else: |
paul@348 | 303 | dt, attr = t |
paul@348 | 304 | return to_utc_datetime(dt) |
paul@289 | 305 | |
paul@289 | 306 | def get_datetime_item(d, name): |
paul@348 | 307 | t = get_item(d, name) |
paul@348 | 308 | if not t: |
paul@348 | 309 | return None |
paul@348 | 310 | else: |
paul@348 | 311 | value, attr = t |
paul@348 | 312 | return get_datetime(value, attr), attr |
paul@213 | 313 | |
paul@213 | 314 | def get_addresses(values): |
paul@213 | 315 | return [address for name, address in email.utils.getaddresses(values)] |
paul@213 | 316 | |
paul@213 | 317 | def get_address(value): |
paul@333 | 318 | value = value.lower() |
paul@333 | 319 | return value.startswith("mailto:") and value[7:] or value |
paul@213 | 320 | |
paul@213 | 321 | def get_uri(value): |
paul@213 | 322 | return value.lower().startswith("mailto:") and value.lower() or ":" in value and value or "mailto:%s" % value.lower() |
paul@213 | 323 | |
paul@309 | 324 | uri_value = get_uri |
paul@309 | 325 | |
paul@309 | 326 | def uri_values(values): |
paul@309 | 327 | return map(get_uri, values) |
paul@309 | 328 | |
paul@213 | 329 | def uri_dict(d): |
paul@213 | 330 | return dict([(get_uri(key), value) for key, value in d.items()]) |
paul@213 | 331 | |
paul@213 | 332 | def uri_item(item): |
paul@213 | 333 | return get_uri(item[0]), item[1] |
paul@213 | 334 | |
paul@213 | 335 | def uri_items(items): |
paul@213 | 336 | return [(get_uri(value), attr) for value, attr in items] |
paul@213 | 337 | |
paul@220 | 338 | # Operations on structure data. |
paul@220 | 339 | |
paul@220 | 340 | def is_new_object(old_sequence, new_sequence, old_dtstamp, new_dtstamp, partstat_set): |
paul@220 | 341 | |
paul@220 | 342 | """ |
paul@220 | 343 | Return for the given 'old_sequence' and 'new_sequence', 'old_dtstamp' and |
paul@220 | 344 | 'new_dtstamp', and the 'partstat_set' indication, whether the object |
paul@220 | 345 | providing the new information is really newer than the object providing the |
paul@220 | 346 | old information. |
paul@220 | 347 | """ |
paul@220 | 348 | |
paul@220 | 349 | have_sequence = old_sequence is not None and new_sequence is not None |
paul@220 | 350 | is_same_sequence = have_sequence and int(new_sequence) == int(old_sequence) |
paul@220 | 351 | |
paul@220 | 352 | have_dtstamp = old_dtstamp and new_dtstamp |
paul@220 | 353 | is_old_dtstamp = have_dtstamp and new_dtstamp < old_dtstamp or old_dtstamp and not new_dtstamp |
paul@220 | 354 | |
paul@220 | 355 | is_old_sequence = have_sequence and ( |
paul@220 | 356 | int(new_sequence) < int(old_sequence) or |
paul@220 | 357 | is_same_sequence and is_old_dtstamp |
paul@220 | 358 | ) |
paul@220 | 359 | |
paul@220 | 360 | return is_same_sequence and partstat_set or not is_old_sequence |
paul@220 | 361 | |
paul@256 | 362 | # NOTE: Need to expose the 100 day window for recurring events in the |
paul@256 | 363 | # NOTE: configuration. |
paul@256 | 364 | |
paul@360 | 365 | def get_window_end(tzid, window_size=100): |
paul@360 | 366 | return to_timezone(datetime.now(), tzid) + timedelta(window_size) |
paul@360 | 367 | |
paul@422 | 368 | def get_tzid(dtstart_attr, dtend_attr): |
paul@422 | 369 | return dtstart_attr.get("TZID") or dtend_attr.get("TZID") |
paul@422 | 370 | |
paul@424 | 371 | def get_periods(obj, tzid, window_end, inclusive=False, origin=False): |
paul@256 | 372 | |
paul@256 | 373 | """ |
paul@256 | 374 | Return periods for the given object 'obj', confining materialised periods |
paul@360 | 375 | to before the given 'window_end' datetime. If 'inclusive' is set to a true |
paul@360 | 376 | value, any period occurring at the 'window_end' will be included. |
paul@424 | 377 | |
paul@424 | 378 | If 'origin' is set to a true value, the property type providing each period |
paul@424 | 379 | will be included in the results, with each result taking the form |
paul@424 | 380 | (start, end, property type). |
paul@256 | 381 | """ |
paul@256 | 382 | |
paul@318 | 383 | rrule = obj.get_value("RRULE") |
paul@318 | 384 | |
paul@318 | 385 | # Use localised datetimes. |
paul@318 | 386 | |
paul@392 | 387 | dtstart, dtstart_attr = obj.get_datetime_item("DTSTART") |
paul@256 | 388 | |
paul@392 | 389 | if obj.has_key("DTEND"): |
paul@392 | 390 | dtend, dtend_attr = obj.get_datetime_item("DTEND") |
paul@392 | 391 | duration = dtend - dtstart |
paul@392 | 392 | elif obj.has_key("DURATION"): |
paul@392 | 393 | duration = obj.get_duration("DURATION") |
paul@392 | 394 | dtend = dtstart + duration |
paul@392 | 395 | dtend_attr = dtstart_attr |
paul@392 | 396 | else: |
paul@392 | 397 | dtend, dtend_attr = dtstart, dtstart_attr |
paul@256 | 398 | |
paul@422 | 399 | tzid = get_tzid(dtstart_attr, dtend_attr) or tzid |
paul@256 | 400 | |
paul@352 | 401 | if not rrule: |
paul@424 | 402 | origin_value = origin and ("DTSTART",) or () |
paul@424 | 403 | periods = [(dtstart, dtend) + origin_value] |
paul@352 | 404 | else: |
paul@352 | 405 | # Recurrence rules create multiple instances to be checked. |
paul@352 | 406 | # Conflicts may only be assessed within a period defined by policy |
paul@352 | 407 | # for the agent, with instances outside that period being considered |
paul@352 | 408 | # unchecked. |
paul@352 | 409 | |
paul@352 | 410 | selector = get_rule(dtstart, rrule) |
paul@352 | 411 | parameters = get_parameters(rrule) |
paul@424 | 412 | origin_value = origin and ("RRULE",) or () |
paul@352 | 413 | periods = [] |
paul@352 | 414 | |
paul@360 | 415 | for start in selector.materialise(dtstart, window_end, parameters.get("COUNT"), parameters.get("BYSETPOS"), inclusive): |
paul@352 | 416 | start = to_timezone(datetime(*start), tzid) |
paul@352 | 417 | end = start + duration |
paul@424 | 418 | periods.append((start, end) + origin_value) |
paul@352 | 419 | |
paul@352 | 420 | # Add recurrence dates. |
paul@256 | 421 | |
paul@352 | 422 | periods = set(periods) |
paul@417 | 423 | rdates = obj.get_date_values("RDATE", tzid) |
paul@352 | 424 | |
paul@352 | 425 | if rdates: |
paul@424 | 426 | origin_value = origin and ("RDATE",) or () |
paul@352 | 427 | for rdate in rdates: |
paul@389 | 428 | if isinstance(rdate, tuple): |
paul@424 | 429 | periods.add(rdate + origin_value) |
paul@389 | 430 | else: |
paul@424 | 431 | periods.add((rdate, rdate + duration) + origin_value) |
paul@424 | 432 | |
paul@424 | 433 | # Return a sorted list of the periods. |
paul@424 | 434 | |
paul@424 | 435 | periods = list(periods) |
paul@428 | 436 | periods.sort(cmp=compare_periods(tzid)) |
paul@352 | 437 | |
paul@352 | 438 | # Exclude exception dates. |
paul@352 | 439 | |
paul@417 | 440 | exdates = obj.get_date_values("EXDATE", tzid) |
paul@256 | 441 | |
paul@352 | 442 | if exdates: |
paul@352 | 443 | for exdate in exdates: |
paul@389 | 444 | if isinstance(exdate, tuple): |
paul@389 | 445 | period = exdate |
paul@389 | 446 | else: |
paul@389 | 447 | period = (exdate, exdate + duration) |
paul@424 | 448 | i = bisect_left(periods, period) |
paul@424 | 449 | while i < len(periods) and periods[i][:2] == period: |
paul@424 | 450 | del periods[i] |
paul@256 | 451 | |
paul@256 | 452 | return periods |
paul@256 | 453 | |
paul@428 | 454 | class compare_periods: |
paul@428 | 455 | def __init__(self, tzid): |
paul@428 | 456 | self.tzid = tzid |
paul@428 | 457 | def __call__(self, first, second): |
paul@428 | 458 | first_start, first_end = first[:2] |
paul@428 | 459 | second_start, second_end = second[:2] |
paul@428 | 460 | return cmp( |
paul@428 | 461 | (to_datetime(first_start, self.tzid), to_datetime(first_end, self.tzid)), |
paul@428 | 462 | (to_datetime(second_start, self.tzid), to_datetime(second_end, self.tzid)) |
paul@428 | 463 | ) |
paul@428 | 464 | |
paul@291 | 465 | def get_periods_for_freebusy(obj, periods, tzid): |
paul@291 | 466 | |
paul@306 | 467 | """ |
paul@306 | 468 | Get free/busy-compliant periods employed by 'obj' from the given 'periods', |
paul@306 | 469 | using the indicated 'tzid' to convert dates to datetimes. |
paul@306 | 470 | """ |
paul@306 | 471 | |
paul@291 | 472 | start, start_attr = obj.get_datetime_item("DTSTART") |
paul@392 | 473 | if obj.has_key("DTEND"): |
paul@392 | 474 | end, end_attr = obj.get_datetime_item("DTEND") |
paul@392 | 475 | elif obj.has_key("DURATION"): |
paul@392 | 476 | duration = obj.get_duration("DURATION") |
paul@392 | 477 | end = start + duration |
paul@392 | 478 | else: |
paul@392 | 479 | end, end_attr = start, start_attr |
paul@291 | 480 | |
paul@422 | 481 | tzid = get_tzid(start_attr, end_attr) or tzid |
paul@291 | 482 | |
paul@291 | 483 | l = [] |
paul@291 | 484 | |
paul@424 | 485 | for t in periods: |
paul@424 | 486 | start, end = t[:2] |
paul@291 | 487 | start, end = get_freebusy_period(start, end, tzid) |
paul@320 | 488 | start, end = [to_timezone(x, "UTC") for x in start, end] |
paul@424 | 489 | l.append((format_datetime(start), format_datetime(end)) + t[2:]) |
paul@291 | 490 | |
paul@291 | 491 | return l |
paul@291 | 492 | |
paul@213 | 493 | # vim: tabstop=4 expandtab shiftwidth=4 |