import Resolver from '../../resolver';
import post from '../../../../services/note/create';
import { IRemoteUser, User } from '../../../../models/entities/user';
import { IAnnounce, INote, getApId, getApIds } from '../../type';
import { fetchNote, resolveNote } from '../../models/note';
import { resolvePerson } from '../../models/person';
import { apLogger } from '../../logger';
import { extractDbHost } from '../../../../misc/convert-host';
import { fetchMeta } from '../../../../misc/fetch-meta';

const logger = apLogger;

/**
 * アナウンスアクティビティを捌きます
 */
export default async function(resolver: Resolver, actor: IRemoteUser, activity: IAnnounce, note: INote): Promise<void> {
	const uri = getApId(activity);

	// アナウンサーが凍結されていたらスキップ
	if (actor.isSuspended) {
		return;
	}

	// アナウンス先をブロックしてたら中断
	const meta = await fetchMeta();
	if (meta.blockedHosts.includes(extractDbHost(uri))) return;

	// 既に同じURIを持つものが登録されていないかチェック
	const exist = await fetchNote(uri);
	if (exist) {
		return;
	}

	// Announce対象をresolve
	let renote;
	try {
		renote = await resolveNote(note);
	} catch (e) {
		// 対象が4xxならスキップ
		if (e.statusCode >= 400 && e.statusCode < 500) {
			logger.warn(`Ignored announce target ${note.inReplyTo} - ${e.statusCode}`);
			return;
		}
		logger.warn(`Error in announce target ${note.inReplyTo} - ${e.statusCode || e}`);
		throw e;
	}

	logger.info(`Creating the (Re)Note: ${uri}`);

	//#region Visibility
	const to = getApIds(activity.to);
	const cc = getApIds(activity.cc);

	const visibility = getVisibility(to, cc, actor);

	let visibleUsers: User[] = [];
	if (visibility == 'specified') {
		visibleUsers = await Promise.all(to.map(uri => resolvePerson(uri)));
	}
	//#endergion

	await post(actor, {
		createdAt: activity.published ? new Date(activity.published) : null,
		renote,
		visibility,
		visibleUsers,
		uri
	});
}

type visibility = 'public' | 'home' | 'followers' | 'specified';

function getVisibility(to: string[], cc: string[], actor: IRemoteUser): visibility {
	const PUBLIC = 'https://www.w3.org/ns/activitystreams#Public';

	if (to.includes(PUBLIC)) {
		return 'public';
	} else if (cc.includes(PUBLIC)) {
		return 'home';
	} else if (to.includes(`${actor.uri}/followers`)) {
		return 'followers';
	} else {
		return 'specified';
	}
}