create an event, newest day first, and a URL you can read

three small things, one of which turned out to be a bug in what shipped an hour
ago.

CREATE. a POST to /_officer/event, and the SIDECAR builds the file — the browser
sends title, when and where. a UID, a DTSTAMP and a UTC timestamp each have
exactly one correct form, and that belongs next to the parser that reads them
back, not in a react component. it writes the minimum a VEVENT can legally be:
no recurrence, no alarms, no attendees. this app cannot show those, and a field
the list cannot display is a field that silently disappears on the next edit.

times go in as UTC. the alternative is DTSTART;TZID plus a VTIMEZONE block
defining that zone's rules, and a subtly wrong VTIMEZONE moves an event by an
hour twice a year. UTC needs no definition and every client renders it local.
all-day is the other trap: RFC 5545 makes DTEND EXCLUSIVE, so a one-day event on
the 29th ends on the 30th — write the 29th and some clients draw nothing at all.
the form takes the last day a person means and the builder adds the day.

NEWEST DAY ON TOP. a calendar accumulates years, so ascending opened on whatever
was imported first and this week was a scroll away. within a day the order stays
chronological, because that is what a day is.

?collection=ra-guide, NOT ?collection=%2Fdav%2F1%2Fra-guide%2F. the path is
/dav/<userId>/<name>/, so the escaped form spent six characters on slashes to
say `ra-guide` and put the owner's user id in a URL people paste at each other.
the name is unique within a user, which is all a selector needs, and the full
path is recovered from the collections list the screen already loaded. a full
path in the param still resolves, because somebody's bookmark has one.

AND THE BUG. setProperty replaced a property's first line and left its
continuation lines behind. a value over 75 octets is FOLDED onto lines starting
with a space — so editing a long summary left the old tail folded onto the new
value, and each edit inherited the last one's ending. it only bites on long
values, which is why the first round of testing missed it. the fix consumes the
whole folded run and folds what it writes; both are now under test, including
the accent-near-the-boundary case that a naive slice(0,75) cuts in half.

verified live: both event shapes written and read back, escaping round-tripped,
and a long summary edited twice with no accumulation.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Officer-Session: 656f5c85-e49a-4f1f-b9f3-042a04b4d043

sidecar/collections.ts

@@ -1,4 +1,4 @@
-import { parseContacts, parseEvents, type CalendarEvent, type Contact } from './ical';
+import { buildEvent, parseContacts, parseEvents, type CalendarEvent, type Contact, type NewEvent } from './ical';
 
 // The JSON door: what Officer's own web UI reads.
 //
@@ -11,8 +11,14 @@ import { parseContacts, parseEvents, type CalendarEvent, type Contact } from './
 // docs/nextcloud-replacement.md, "two front doors, not one".
 
 export type Collection = {
-  /** DAV path, relative to the /dav mount — the id the UI passes back. */
+  /** DAV path, relative to the /dav mount — the id the UI passes back on every read. */
   path: string;
+  /**
+   * The last path segment, and the only part of the path that identifies anything. The web URLs select
+   * with this rather than the whole path: `?collection=personal` instead of `?collection=%2Fdav%2F1%2Fpersonal%2F`,
+   * which is the same information without the user id, the mount point and six escaped slashes.
+   */
+  name: string;
   displayName: string;
   kind: 'calendar' | 'addressbook';
   /** Radicale stores a per-collection colour when a client sets one; used for the UI's dot. */
@@ -77,6 +83,7 @@ export async function listCollections(fetcher: Fetcher, userId: string): Promise
 
     collections.push({
       path,
+      name: lastSegment,
       // Radicale's default displayname is the collection's own path ("1/work"), which is an id, not a
       // name. A real client sets something human when it creates a collection; until one does, the last
       // segment is the better label — and it is what every DAV client falls back to anyway.
@@ -150,3 +157,26 @@ export async function listContacts(fetcher: Fetcher, path: string): Promise<Cont
   const objects = await readObjects(fetcher, path, 'addressbook');
   return objects.flatMap((o) => parseContacts(o.data).map((c) => ({ ...c, href: o.href })));
 }
+
+/**
+ * Create one event, in its own file.
+ *
+ * THE FILENAME IS A FRESH UUID, and it is also the UID. Not because a client may assume they match —
+ * nothing here does, and the listing carries the real href precisely because they often do not — but
+ * because a new name has to come from somewhere, and one that cannot collide is the cheapest kind.
+ *
+ * `If-None-Match: *` makes the PUT conditional on the file NOT existing, so a retried request cannot
+ * quietly overwrite an event created by the first attempt.
+ */
+export async function createEvent(fetcher: Fetcher, collection: string, event: NewEvent): Promise<{ href: string }> {
+  const uid = crypto.randomUUID();
+  const href = `${collection.replace(/\/$/, '')}/${uid}.ics`;
+
+  const res = await fetcher(href, {
+    method: 'PUT',
+    headers: { 'Content-Type': 'text/calendar; charset=utf-8', 'If-None-Match': '*' },
+    body: buildEvent(uid, event),
+  });
+  if (!res.ok) throw new Error(`radicale answered ${res.status}`);
+  return { href };
+}