/**
 * Decks-API — event-sourced gegen `@mana/event-sync`.
 *
 * Migration L-1f (2026-05-20): User-owned Reads + Writes laufen jetzt
 * lokal über die IndexedDB-Projektion. Server-AI-Endpoints
 * (generate, generate-from-image, distractors) bleiben HTTP — sie
 * konsumieren Tier-gated mana-credits und returnen JSON, das der Client
 * dann als Events emittiert. Marketplace-Reads bleiben ebenfalls HTTP
 * (cross-user, kein eigener event-stream pro User).
 */

import type { Deck, DeckCreate, DeckUpdate } from '@wordeck/domain';
import type { WordeckDeckState as DeckProjection } from '@mana/shared-schemas';
import { ulid } from 'ulid';

import { api, apiForm } from './client.ts';
import { deckAggregateId, deckStateToRow } from './event-adapters.ts';
import { emitEvent } from './event-builder.ts';
import { getSync } from '../sync.svelte.ts';

export async function listDecks(
	opts: { forkedFromMarketplace?: boolean; archived?: boolean } = {},
): Promise<{ decks: Deck[]; total: number }> {
	const sync = await getSync();
	const all = await sync.aggregateList<DeckProjection>('deck');
	const decks = all
		.filter(({ state }) => state.deletedAt === null)
		.filter(({ state }) =>
			opts.archived ? state.archivedAt !== null : state.archivedAt === null,
		)
		.filter(({ state }) =>
			opts.forkedFromMarketplace ? state.forkedFromMarketplaceDeckId !== null : true,
		)
		.map(({ aggregateId, state }) => deckStateToRow(aggregateId, state));
	return { decks, total: decks.length };
}

export async function getDeck(id: string): Promise<Deck> {
	const sync = await getSync();
	const state = await sync.aggregateState<DeckProjection>(deckAggregateId(id));
	if (!state || state.deletedAt) {
		throw new Error(`deck ${id} nicht gefunden`);
	}
	return deckStateToRow(deckAggregateId(id), state);
}

export async function createDeck(input: DeckCreate): Promise<Deck> {
	const deckId = ulid();
	const aggregateId = deckAggregateId(deckId);
	await emitEvent(aggregateId, 'DeckCreated', {
		deckId,
		name: input.name,
		description: input.description ?? null,
		color: input.color ?? null,
		category: input.category ?? null,
	});
	// Optionale Init-Settings hinterherschicken
	if (input.fsrs_settings && Object.keys(input.fsrs_settings).length > 0) {
		await emitEvent(aggregateId, 'DeckFsrsSettingsUpdated', {
			deckId,
			newSettingsJson: JSON.stringify(input.fsrs_settings),
		});
	}
	return getDeck(deckId);
}

export async function updateDeck(id: string, patch: DeckUpdate): Promise<Deck> {
	const aggregateId = deckAggregateId(id);

	if (patch.name !== undefined) {
		await emitEvent(aggregateId, 'DeckRenamed', { deckId: id, newName: patch.name });
	}
	if (patch.description !== undefined) {
		await emitEvent(aggregateId, 'DeckDescriptionUpdated', {
			deckId: id,
			newDescription: patch.description ?? null,
		});
	}
	if (patch.color !== undefined) {
		await emitEvent(aggregateId, 'DeckColorChanged', {
			deckId: id,
			newColor: patch.color ?? null,
		});
	}
	if (patch.category !== undefined) {
		await emitEvent(aggregateId, 'DeckCategoryChanged', {
			deckId: id,
			newCategory: patch.category ?? null,
		});
	}
	if (patch.fsrs_settings !== undefined) {
		await emitEvent(aggregateId, 'DeckFsrsSettingsUpdated', {
			deckId: id,
			newSettingsJson: JSON.stringify(patch.fsrs_settings),
		});
	}
	if (patch.archived !== undefined) {
		await emitEvent(
			aggregateId,
			patch.archived ? 'DeckArchived' : 'DeckUnarchived',
			{ deckId: id },
		);
	}
	if (patch.visibility !== undefined && patch.visibility !== 'private') {
		await emitEvent(aggregateId, 'DeckPublished', {
			deckId: id,
			visibility: patch.visibility,
			license: 'CC-BY-4.0',
		});
	}
	return getDeck(id);
}

export async function archiveDeck(id: string): Promise<Deck> {
	return updateDeck(id, { archived: true });
}

export async function unarchiveDeck(id: string): Promise<Deck> {
	return updateDeck(id, { archived: false });
}

export async function deleteDeck(id: string): Promise<{ deleted: string }> {
	await emitEvent(deckAggregateId(id), 'DeckDeleted', { deckId: id });
	return { deleted: id };
}

/**
 * Marketplace-Source-Lookup bleibt HTTP — Marketplace ist cross-user und
 * lebt im Server-pgSchema `marketplace.*`, nicht im Per-User-Event-Stream.
 */
export function getMarketplaceSource(id: string) {
	return api<{ slug: string } | null>(`/api/v1/decks/${id}/marketplace-source`);
}

/**
 * duplicateDeck bleibt vorerst HTTP — der Server kopiert Karten in
 * einer Transaktion. Sobald Cards-API auf events lebt, kann das
 * client-side als Event-Burst erfolgen.
 */
export function duplicateDeck(id: string) {
	return api<Deck>(`/api/v1/decks/${id}/duplicate`, { method: 'POST' });
}

/**
 * AI-Generate-Endpoints bleiben HTTP — Tier-gated über mana-credits,
 * Server hat Prompt-Templates + LLM-Provider-Routing. Result wird heute
 * direkt als Deck+Cards persistiert vom Server. Follow-up-Task: Result
 * als Event-Burst zum Client schicken, Client emittet lokal.
 */
export function generateDeck(input: {
	prompt: string;
	language?: string;
	count?: number;
	url?: string;
}) {
	return api<{ deck: Deck; cards_created: number }>('/api/v1/decks/generate', {
		method: 'POST',
		body: input,
	});
}

export function fetchDistractors(
	deckId: string,
	opts: { cardId?: string; count?: number; field?: string } = {},
) {
	const params = new URLSearchParams();
	if (opts.cardId) params.set('card_id', opts.cardId);
	if (opts.count) params.set('count', String(opts.count));
	if (opts.field) params.set('field', opts.field);
	const qs = params.size ? `?${params}` : '';
	return api<{ distractors: string[] }>(`/api/v1/decks/${deckId}/distractors${qs}`);
}

export function generateDeckFromImage(
	files: File | File[],
	opts: { language?: string; count?: number; url?: string },
) {
	const arr = Array.isArray(files) ? files : [files];
	if (arr.length === 0) {
		return api<{ deck: Deck; cards_created: number }>('/api/v1/decks/from-image', {
			method: 'POST',
			body: { language: opts.language, count: opts.count, url: opts.url },
		});
	}
	const form = new FormData();
	for (const f of arr) form.append('file', f);
	if (opts.language) form.append('language', opts.language);
	if (opts.count != null) form.append('count', String(opts.count));
	if (opts.url) form.append('url', opts.url);
	return apiForm<{ deck: Deck; cards_created: number }>('/api/v1/decks/from-image', form);
}