conductor(checkpoint): Checkpoint end of Phase 2: Core Logic

icalendar.ts

@@ -1,25 +1,12 @@
 import { clientStore, config, datastore, editor, index } from "@silverbulletmd/silverbullet/syscalls";
 import { convertIcsCalendar } from "https://esm.sh/ts-ics@2.4.0";
+import { getUtcOffsetMs, resolveIanaName } from "./timezones.ts";
 
 const VERSION = "0.3.25";
 const CACHE_KEY = "icalendar:lastSync";
 
 console.log(`[iCalendar] Plug script executing at top level (Version ${VERSION})`);
 
-const TIMEZONE_OFFSETS: Record<string, number> = {
-  "GMT Standard Time": 0,
-  "W. Europe Standard Time": 1,
-  "Central Europe Standard Time": 1,
-  "Romance Standard Time": 1,
-  "Central European Standard Time": 1,
-  "Eastern Standard Time": -5,
-  "Central Standard Time": -6,
-  "Mountain Standard Time": -7,
-  "Pacific Standard Time": -8,
-  "UTC": 0,
-  "None": 0
-};
-
 // ============================================================================
 // Utility Functions
 // ============================================================================
@@ -86,18 +73,14 @@ function convertDatesToStrings<T>(obj: T): any {
 // Configuration Functions
 // ============================================================================
 
-async function getSources(): Promise<{ sources: any[], tzShift: number }> {
+async function getSources(): Promise<any[]> {
   try {
-    const rawConfig = await config.get("icalendar", { sources: [] });
+    const rawConfig = await config.get("icalendar", { sources: [] }) as any;
     console.log("[iCalendar] Raw config retrieved:", JSON.stringify(rawConfig));
     
     let sources = rawConfig.sources || [];
-    let tzShift = rawConfig.tzShift || 0;
 
     if (sources && typeof sources === "object" && !Array.isArray(sources)) {
-        if (sources.tzShift !== undefined && tzShift === 0) {
-            tzShift = sources.tzShift;
-        }
         const sourceArray = [];
         for (const key in sources) {
             if (sources[key] && typeof sources[key].url === "string") {
@@ -107,10 +90,10 @@ async function getSources(): Promise<{ sources: any[], tzShift: number }> {
         sources = sourceArray;
     }
 
-    return { sources, tzShift };
+    return sources;
   } catch (e) {
     console.error("[iCalendar] Error in getSources:", e);
-    return { sources: [], tzShift: 0 };
+    return [];
   }
 }
 
@@ -118,7 +101,55 @@ async function getSources(): Promise<{ sources: any[], tzShift: number }> {
 // Calendar Fetching & Parsing
 // ============================================================================
 
-async function fetchAndParseCalendar(source: any, hourShift = 0): Promise<any[]> {
+/**
+ * Resolves the event start as a UTC Date object using DST-aware resolution.
+ */
+export async function resolveEventStart(icsEvent: any): Promise<Date | null> {
+  const obj = icsEvent.start;
+  if (!obj) return null;
+
+  // 1. Extract the wall-clock local datetime string
+  let wallClock: string | null = null;
+  if (obj.local?.date) {
+    const d = obj.local.date;
+    wallClock = d instanceof Date ? d.toISOString() : String(d);
+  } else if (obj.date) {
+    const d = obj.date;
+    wallClock = d instanceof Date ? d.toISOString() : String(d);
+  }
+
+  if (!wallClock) return null;
+
+  // 2. Resolve IANA timezone
+  const rawTz = obj.local?.timezone || (obj as any).timezone || "UTC";
+  const ianaName = resolveIanaName(rawTz);
+
+  // Strip any trailing Z — this is treated as wall-clock local time
+  wallClock = wallClock.replace(/Z$/, "");
+
+  if (!ianaName) {
+    console.warn(`[iCalendar] Unknown timezone: "${rawTz}" - falling back to UTC for event "${icsEvent.summary}"`);
+    // Fallback to parsing as UTC but mark it
+    const utcDate = new Date(wallClock + (wallClock.includes("T") ? "" : "T00:00:00") + "Z");
+    if (isNaN(utcDate.getTime())) return null;
+    return utcDate;
+  }
+
+  // 3. Parse the wall-clock time as a UTC instant (no offset yet)
+  const wallClockAsUtc = new Date(wallClock + (wallClock.includes("T") ? "" : "T00:00:00") + "Z");
+  if (isNaN(wallClockAsUtc.getTime())) {
+      console.error(`[iCalendar] Invalid wallClock date: ${wallClock}`);
+      return null;
+  }
+
+  // 4. Get the DST-aware offset for this IANA zone at this instant
+  const offsetMs = getUtcOffsetMs(ianaName, wallClockAsUtc);
+  
+  // 5. Convert: UTC = wall-clock - offset
+  return new Date(wallClockAsUtc.getTime() - offsetMs);
+}
+
+async function fetchAndParseCalendar(source: any): Promise<any[]> {
   console.log(`[iCalendar] Fetching from: ${source.url}`);
   try {
     const response = await fetch(source.url);
@@ -134,36 +165,29 @@ async function fetchAndParseCalendar(source: any, hourShift = 0): Promise<any[]>
     
     const events: any[] = [];
     for (const icsEvent of calendar.events) {
-      const obj = icsEvent.start;
-      if (!obj) continue;
-
-      let wallTimeStr = "";
-      if (obj.local && obj.local.date) {
-          wallTimeStr = typeof obj.local.date === "string" ? obj.local.date : (obj.local.date instanceof Date ? obj.local.date.toISOString() : String(obj.local.date));
-      } else if (obj.date) {
-          wallTimeStr = typeof obj.date === "string" ? obj.date : (obj.date instanceof Date ? obj.date.toISOString() : String(obj.date));
-      }
-      
-      if (!wallTimeStr) continue;
-
-      const baseDate = new Date(wallTimeStr.replace("Z", "") + "Z");
-      const tzName = obj.local?.timezone || obj.timezone || "UTC";
-      const sourceOffset = TIMEZONE_OFFSETS[tzName] ?? 0;
-      const utcMillis = baseDate.getTime() - (sourceOffset * 3600000);
-      const finalDate = new Date(utcMillis + (hourShift * 3600000));
+      const finalDate = await resolveEventStart(icsEvent);
+      if (!finalDate) continue;
       
       const localIso = localDateString(finalDate);
       const uniqueKey = `${localIso}${icsEvent.uid || icsEvent.summary || ''}`;
       const ref = await sha256Hash(uniqueKey);
 
-      events.push(convertDatesToStrings({
+      const eventData = {
         ...icsEvent,
         name: icsEvent.summary || "Untitled Event",
         start: localIso,
         ref,
         tag: "ical-event",
         sourceName: source.name
-      }));
+      };
+
+      // Add warning if timezone was unknown
+      const rawTz = icsEvent.start?.local?.timezone || (icsEvent.start as any)?.timezone || "UTC";
+      if (rawTz !== "UTC" && rawTz !== "None" && !resolveIanaName(rawTz)) {
+          eventData.description = `(Warning: Unknown timezone "${rawTz}") ${eventData.description || ""}`;
+      }
+
+      events.push(convertDatesToStrings(eventData));
     }
     return events;
   } catch (err) {
@@ -174,13 +198,13 @@ async function fetchAndParseCalendar(source: any, hourShift = 0): Promise<any[]>
 
 export async function syncCalendars() {
   try {
-    const { sources, tzShift } = await getSources();
+    const sources = await getSources();
     if (sources.length === 0) return;
     
     await editor.flashNotification("Syncing calendars...", "info");
     const allEvents: any[] = [];
     for (const source of sources) {
-      const events = await fetchAndParseCalendar(source, tzShift);
+      const events = await fetchAndParseCalendar(source);
       allEvents.push(...events);
     }
     await index.indexObjects("$icalendar", allEvents);

icalendar_test.ts

@@ -0,0 +1,45 @@
+import { assertEquals } from "jsr:@std/assert";
+import { resolveEventStart } from "./icalendar.ts";
+
+Deno.test("resolveEventStart - local date with timezone", async () => {
+  const icsEvent = {
+    summary: "Test Event",
+    start: {
+      date: "2025-01-15T12:00:00.000",
+      local: {
+        date: "2025-01-15T07:00:00.000",
+        timezone: "Eastern Standard Time"
+      }
+    }
+  };
+  
+  const result = await resolveEventStart(icsEvent);
+  assertEquals(result?.toISOString(), "2025-01-15T12:00:00.000Z");
+});
+
+Deno.test("resolveEventStart - DST check (Summer)", async () => {
+  const icsEvent = {
+    summary: "Test Event DST",
+    start: {
+      date: "2025-07-15T11:00:00.000",
+      local: {
+        date: "2025-07-15T07:00:00.000",
+        timezone: "Eastern Standard Time"
+      }
+    }
+  };
+  
+  const result = await resolveEventStart(icsEvent);
+  assertEquals(result?.toISOString(), "2025-07-15T11:00:00.000Z");
+});
+
+Deno.test("resolveEventStart - UTC event", async () => {
+  const icsEvent = {
+    summary: "UTC Event",
+    start: {
+      date: "2025-01-15T12:00:00.000Z"
+    }
+  };
+  const result = await resolveEventStart(icsEvent);
+  assertEquals(result?.toISOString(), "2025-01-15T12:00:00.000Z");
+});