wordeck/apps/api/src/share-handlers/index.ts

import { newReview, subIndexCount } from '@cards/domain';
import type { QuotePayload, TextPayload, LinkPayload } from '@cards/domain';

import type { CardsDb } from '../db/connection.ts';
import { cards, reviews } from '../db/schema/index.ts';
import { ensureInboxDeck } from '../lib/inbox-deck.ts';
import { ulid } from '../lib/ulid.ts';

/**
 * Antwort-Shape eines Share-Handlers — wird vom Receive-Endpoint
 * an den sendenden Peer zurückgegeben.
 */
export type HandlerResult = {
	target_link: string;
	resulting_id: string;
};

const APP_BASE_URL = process.env.CARDS_PUBLIC_URL ?? 'https://cardecky.mana.how';

/**
 * Legt eine basic-Karte mit (front,back) im Inbox-Deck an, inkl.
 * der ts-fsrs-Initial-Reviews. Gibt Karte-ID + Deep-Link zurück.
 */
async function persistCardInInbox(
	db: CardsDb,
	userId: string,
	front: string,
	back: string
): Promise<HandlerResult> {
	const inbox = await ensureInboxDeck(db, userId);
	const cardId = ulid();
	const now = new Date();

	await db.transaction(async (tx) => {
		await tx.insert(cards).values({
			id: cardId,
			deckId: inbox.id,
			userId,
			type: 'basic',
			fields: { front, back },
			mediaRefs: [],
			createdAt: now,
			updatedAt: now,
		});

		const initial = Array.from({ length: subIndexCount('basic') }, (_, i) => i).map(
			(subIndex) => {
				const r = newReview({ userId, cardId, subIndex, now });
				return {
					cardId: r.card_id,
					subIndex: r.sub_index,
					userId: r.user_id,
					due: new Date(r.due),
					stability: r.stability,
					difficulty: r.difficulty,
					elapsedDays: r.elapsed_days,
					scheduledDays: r.scheduled_days,
					learningSteps: r.learning_steps,
					reps: r.reps,
					lapses: r.lapses,
					state: r.state,
					lastReview: r.last_review ? new Date(r.last_review) : null,
				};
			}
		);
		if (initial.length > 0) {
			await tx.insert(reviews).values(initial);
		}
	});

	return {
		target_link: `${APP_BASE_URL}/c/${cardId}`,
		resulting_id: cardId,
	};
}

/**
 * mana/quote → Karte. Front = Zitat-Text, Back = Quelle (URL bevorzugt,
 * sonst Source-String, sonst leer).
 */
export async function createCardFromQuote(
	db: CardsDb,
	userId: string,
	payload: QuotePayload
): Promise<HandlerResult> {
	const front = payload.text;
	const back = payload.source_url ?? payload.source ?? '';
	return persistCardInInbox(db, userId, front, back);
}

/**
 * mana/link → Karte. Front = Titel (oder URL falls kein Titel),
 * Back = URL + Description/Snippet.
 */
export async function saveLinkAsCard(
	db: CardsDb,
	userId: string,
	payload: LinkPayload
): Promise<HandlerResult> {
	const front = payload.title ?? payload.url;
	const summary = payload.description ?? payload.snippet ?? '';
	const back = summary ? `${payload.url}\n\n${summary}` : payload.url;
	return persistCardInInbox(db, userId, front, back);
}

/**
 * mana/text → Karte. Front = erste Zeile (oder erste 200 Zeichen),
 * Back = Rest. Heuristisch — User kann später trennen.
 */
export async function createCardFromText(
	db: CardsDb,
	userId: string,
	payload: TextPayload
): Promise<HandlerResult> {
	const text = payload.text.trim();
	const firstNl = text.indexOf('\n');
	const frontEnd = firstNl > 0 && firstNl < 200 ? firstNl : Math.min(200, text.length);
	const front = text.slice(0, frontEnd).trim();
	const back = text.slice(frontEnd).trim();
	return persistCardInInbox(db, userId, front, back || '(weiter ausarbeiten)');
}

/** Manifest-Handler-Map. Key = `accepts[].handler` aus app-manifest.json. */
export const SHARE_HANDLERS = {
	create_card_from_quote: createCardFromQuote,
	save_link_as_card: saveLinkAsCard,
	create_card_from_text: createCardFromText,
} as const;

export type ShareHandlerName = keyof typeof SHARE_HANDLERS;