feat: add CalDAV source provider (#111)

Wire CalDavSourceProvider into the backend to support CalDAV
calendar sources (e.g. iCloud) with basic auth. Config accepts
serverUrl, username, lookAheadDays, and timeZone. Credentials
(app-specific password) are stored encrypted via the existing
credential storage infrastructure.

Co-authored-by: Ona <no-reply@ona.com>

apps/aelis-backend/src/caldav/provider.test.ts

@@ -0,0 +1,85 @@
+import { describe, expect, test } from "bun:test"
+
+import { CalDavSourceProvider } from "./provider.ts"
+
+describe("CalDavSourceProvider", () => {
+	const provider = new CalDavSourceProvider()
+
+	test("sourceId is aelis.caldav", () => {
+		expect(provider.sourceId).toBe("aelis.caldav")
+	})
+
+	test("throws when credentials are null", async () => {
+		const config = { serverUrl: "https://caldav.icloud.com", username: "user@icloud.com" }
+		await expect(provider.feedSourceForUser("user-1", config, null)).rejects.toThrow(
+			"No CalDAV credentials configured",
+		)
+	})
+
+	test("throws when credentials are missing password", async () => {
+		const config = { serverUrl: "https://caldav.icloud.com", username: "user@icloud.com" }
+		await expect(provider.feedSourceForUser("user-1", config, {})).rejects.toThrow(
+			"password must be a string",
+		)
+	})
+
+	test("throws when config is missing serverUrl", async () => {
+		const credentials = { password: "app-specific-password" }
+		await expect(
+			provider.feedSourceForUser("user-1", { username: "user@icloud.com" }, credentials),
+		).rejects.toThrow("Invalid CalDAV config")
+	})
+
+	test("throws when config is missing username", async () => {
+		const credentials = { password: "app-specific-password" }
+		await expect(
+			provider.feedSourceForUser("user-1", { serverUrl: "https://caldav.icloud.com" }, credentials),
+		).rejects.toThrow("Invalid CalDAV config")
+	})
+
+	test("throws when config has extra keys", async () => {
+		const config = {
+			serverUrl: "https://caldav.icloud.com",
+			username: "user@icloud.com",
+			extra: true,
+		}
+		const credentials = { password: "app-specific-password" }
+		await expect(provider.feedSourceForUser("user-1", config, credentials)).rejects.toThrow(
+			"Invalid CalDAV config",
+		)
+	})
+
+	test("throws when credentials have extra keys", async () => {
+		const config = { serverUrl: "https://caldav.icloud.com", username: "user@icloud.com" }
+		const credentials = { password: "app-specific-password", extra: true }
+		await expect(provider.feedSourceForUser("user-1", config, credentials)).rejects.toThrow(
+			"extra must be removed",
+		)
+	})
+
+	test("returns CalDavSource with valid config and credentials", async () => {
+		const config = {
+			serverUrl: "https://caldav.icloud.com",
+			username: "user@icloud.com",
+			lookAheadDays: 3,
+			timeZone: "Europe/London",
+		}
+		const credentials = { password: "app-specific-password" }
+
+		const source = await provider.feedSourceForUser("user-1", config, credentials)
+		expect(source).toBeDefined()
+		expect(source.id).toBe("aelis.caldav")
+	})
+
+	test("returns CalDavSource with minimal config", async () => {
+		const config = {
+			serverUrl: "https://caldav.icloud.com",
+			username: "user@icloud.com",
+		}
+		const credentials = { password: "app-specific-password" }
+
+		const source = await provider.feedSourceForUser("user-1", config, credentials)
+		expect(source).toBeDefined()
+		expect(source.id).toBe("aelis.caldav")
+	})
+})