pageta-native/Tests/UnitTests/EventSyncReducerTests.swift

import ManaEventSync
@testable import PagetaNative
import XCTest

/// Reducer-Tests für die π-11 Event-Sync-Migration. Sicherstellt, dass
/// Replay über Events den erwarteten State produziert. Pendant-Tests
/// für die Web-Seite leben in `apps/web/src/lib/event-sync-api.test.ts`
/// (sofern dort vorhanden — sonst hier die führende Doku).
final class EventSyncReducerTests: XCTestCase {
	// MARK: - Helpers

	private func envelope(
		_ type: String,
		aggregateId: String = "article:01ABC",
		userId: String = "user-1",
		occurredAt: String = "2026-05-20T10:00:00Z",
		payload: some Encodable
	) throws -> EventEnvelope {
		try EventEnvelope(
			eventId: "evt-\(type)",
			aggregateId: aggregateId,
			appId: "pageta",
			eventType: type,
			eventVersion: 1,
			occurredAt: occurredAt,
			receivedAt: nil,
			sequenceNumber: nil,
			causationId: nil,
			correlationId: nil,
			actor: .user(principalId: userId),
			attributedToUserId: userId,
			origin: "user",
			idempotencyKey: "idem-\(type)-\(aggregateId)",
			payload: JSONValue.from(payload)
		)
	}

	private func sampleSavedPayload(id: String = "01ABC") -> ArticleSavedPayload {
		ArticleSavedPayload(
			articleId: id,
			originalUrl: "https://example.com/foo",
			urlHash: "abc123",
			title: "Foo",
			excerpt: "kurz",
			content: "Inhalt",
			author: "Autor",
			siteName: "Example",
			imageUrl: nil,
			wordCount: 100,
			readingTimeMinutes: 1,
			publishedAt: nil,
			userNote: nil
		)
	}

	// MARK: - Article reducer

	func testReplayArticle_emptyEvents_returnsNil() {
		XCTAssertNil(Reducers.replayArticle([]))
	}

	func testReplayArticle_savedOnly_projectsInitialState() throws {
		let e = try envelope(EventType.articleSaved, payload: sampleSavedPayload())
		let state = Reducers.replayArticle([e])
		XCTAssertEqual(state?.id, "01ABC")
		XCTAssertEqual(state?.title, "Foo")
		XCTAssertEqual(state?.status, .unread)
		XCTAssertEqual(state?.readingProgress, 0)
		XCTAssertFalse(state?.isFavorite ?? true)
		XCTAssertNil(state?.deletedAt)
		XCTAssertEqual(state?.savedAt, "2026-05-20T10:00:00Z")
	}

	func testReplayArticle_statusChanged_setsStatusAndReadAt() throws {
		let saved = try envelope(EventType.articleSaved, payload: sampleSavedPayload())
		let changed = try envelope(
			EventType.articleStatusChanged,
			occurredAt: "2026-05-20T11:00:00Z",
			payload: ArticleStatusChangedPayload(articleId: "01ABC", newStatus: .finished)
		)
		let state = Reducers.replayArticle([saved, changed])
		XCTAssertEqual(state?.status, .finished)
		XCTAssertEqual(state?.readAt, "2026-05-20T11:00:00Z")
	}

	func testReplayArticle_favoriteAndProgress() throws {
		let saved = try envelope(EventType.articleSaved, payload: sampleSavedPayload())
		let fav = try envelope(
			EventType.articleFavoriteToggled,
			payload: ArticleFavoriteToggledPayload(articleId: "01ABC", isFavorite: true)
		)
		let progress = try envelope(
			EventType.articleProgressUpdated,
			payload: ArticleProgressUpdatedPayload(articleId: "01ABC", newProgress: 0.42)
		)
		let state = Reducers.replayArticle([saved, fav, progress])
		XCTAssertTrue(state?.isFavorite ?? false)
		XCTAssertEqual(state?.readingProgress, 0.42)
	}

	func testReplayArticle_deletedSetsTombstone() throws {
		let saved = try envelope(EventType.articleSaved, payload: sampleSavedPayload())
		let deleted = try envelope(
			EventType.articleDeleted,
			occurredAt: "2026-05-20T12:00:00Z",
			payload: ArticleDeletedPayload(articleId: "01ABC")
		)
		let state = Reducers.replayArticle([saved, deleted])
		XCTAssertEqual(state?.deletedAt, "2026-05-20T12:00:00Z")
	}

	func testReplayArticle_unknownEventTypeIsSkipped() throws {
		let saved = try envelope(EventType.articleSaved, payload: sampleSavedPayload())
		struct Dummy: Codable { let foo: String }
		let unknown = try envelope("SomeFutureEvent", payload: Dummy(foo: "bar"))
		let state = Reducers.replayArticle([saved, unknown])
		// Saved-State unverändert.
		XCTAssertEqual(state?.title, "Foo")
		XCTAssertEqual(state?.status, .unread)
	}

	func testReplayArticle_tagsSetReplacesArray() throws {
		let saved = try envelope(EventType.articleSaved, payload: sampleSavedPayload())
		let tags1 = try envelope(
			EventType.articleTagsSet,
			payload: ArticleTagsSetPayload(articleId: "01ABC", tags: ["a", "b"])
		)
		let tags2 = try envelope(
			EventType.articleTagsSet,
			payload: ArticleTagsSetPayload(articleId: "01ABC", tags: ["a", "b", "c"])
		)
		let state = Reducers.replayArticle([saved, tags1, tags2])
		XCTAssertEqual(state?.tags, ["a", "b", "c"])
	}

	// MARK: - Highlight reducer

	func testReplayHighlight_createdAndDeleted() throws {
		let created = try envelope(
			EventType.highlightCreated,
			aggregateId: "highlight:H1",
			payload: HighlightCreatedPayload(
				highlightId: "H1",
				articleId: "01ABC",
				text: "wichtige Stelle",
				note: nil,
				color: .yellow,
				startOffset: 0,
				endOffset: 0,
				contextBefore: nil,
				contextAfter: nil
			)
		)
		let s1 = Reducers.replayHighlight([created])
		XCTAssertEqual(s1?.id, "H1")
		XCTAssertEqual(s1?.text, "wichtige Stelle")
		XCTAssertNil(s1?.deletedAt)

		let deleted = try envelope(
			EventType.highlightDeleted,
			aggregateId: "highlight:H1",
			occurredAt: "2026-05-20T13:00:00Z",
			payload: HighlightDeletedPayload(highlightId: "H1")
		)
		let s2 = Reducers.replayHighlight([created, deleted])
		XCTAssertEqual(s2?.deletedAt, "2026-05-20T13:00:00Z")
	}

	// MARK: - JSONValue roundtrip

	func testJSONValue_roundtripStruct() throws {
		let payload = ArticleStatusChangedPayload(articleId: "X", newStatus: .reading)
		let value = try JSONValue.from(payload)
		let decoded: ArticleStatusChangedPayload = try value.decode()
		XCTAssertEqual(decoded.articleId, "X")
		XCTAssertEqual(decoded.newStatus, .reading)
	}

	// MARK: - ULID

	func testULID_isSortableByCreationOrder() {
		let a = ULID.generate()
		// minimaler Schlaf damit der Millis-Anteil sich ändert
		Thread.sleep(forTimeInterval: 0.002)
		let b = ULID.generate()
		XCTAssertEqual(a.count, 26)
		XCTAssertEqual(b.count, 26)
		XCTAssertLessThan(a, b, "ULIDs sollen lexikografisch nach Zeit sortieren")
	}
}