feat(integrations): add ICal (#3980)

Co-authored-by: Meier Lukas <meierschlumpf@gmail.com>

packages/integrations/src/ical/ical-integration.ts

@@ -0,0 +1,67 @@
+import ICAL from "ical.js";
+
+import { fetchWithTrustedCertificatesAsync } from "@homarr/certificates/server";
+
+import type { IntegrationTestingInput } from "../base/integration";
+import { Integration } from "../base/integration";
+import { TestConnectionError } from "../base/test-connection/test-connection-error";
+import type { TestingResult } from "../base/test-connection/test-connection-service";
+import type { ICalendarIntegration } from "../interfaces/calendar/calendar-integration";
+import type { CalendarEvent } from "../interfaces/calendar/calendar-types";
+
+export class ICalIntegration extends Integration implements ICalendarIntegration {
+  async getCalendarEventsAsync(start: Date, end: Date): Promise<CalendarEvent[]> {
+    const response = await fetchWithTrustedCertificatesAsync(super.getSecretValue("url"));
+    const result = await response.text();
+    const jcal = ICAL.parse(result) as unknown[];
+    const comp = new ICAL.Component(jcal);
+
+    return comp.getAllSubcomponents("vevent").reduce((prev, vevent) => {
+      const event = new ICAL.Event(vevent);
+      const startDate = event.startDate.toJSDate();
+      const endDate = event.endDate.toJSDate();
+
+      if (startDate > end) return prev;
+      if (endDate < start) return prev;
+
+      return prev.concat({
+        title: event.summary,
+        subTitle: null,
+        description: event.description,
+        startDate,
+        endDate,
+        image: null,
+        location: event.location,
+        indicatorColor: "red",
+        links: [],
+      });
+    }, [] as CalendarEvent[]);
+  }
+
+  protected async testingAsync(input: IntegrationTestingInput): Promise<TestingResult> {
+    const response = await input.fetchAsync(super.getSecretValue("url"));
+    if (!response.ok) return TestConnectionError.StatusResult(response);
+
+    const result = await response.text();
+
+    try {
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+      const jcal = ICAL.parse(result);
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
+      const comp = new ICAL.Component(jcal);
+      return comp.getAllSubcomponents("vevent").length > 0
+        ? { success: true }
+        : TestConnectionError.ParseResult({
+            name: "Calendar parse error",
+            message: "No events found",
+            cause: new Error("No events found"),
+          });
+    } catch (error) {
+      return TestConnectionError.ParseResult({
+        name: "Calendar parse error",
+        message: "Failed to parse calendar",
+        cause: error as Error,
+      });
+    }
+  }
+}