import { getDb } from "../index.ts";
import type { WikiRow } from "../types.ts";

export interface ModerationRow {
	subject_type: "wiki" | "did";
	subject: string;
	reason: string | null;
	moderator: string | null;
	created_at: string;
}

// Splice into a WHERE clause on alias `w`.
export const WIKI_NOT_MODERATED = `
	w.at_uri NOT IN (SELECT subject FROM moderation_actions WHERE subject_type = 'wiki')
	AND w.did NOT IN (SELECT subject FROM moderation_actions WHERE subject_type = 'did')`;

function upsert(
	subjectType: "wiki" | "did",
	subject: string,
	reason: string | null,
	moderator: string | null,
): void {
	const db = getDb();
	db.run(
		`INSERT INTO moderation_actions (subject_type, subject, reason, moderator)
		 VALUES (?, ?, ?, ?)
		 ON CONFLICT(subject_type, subject) DO UPDATE SET
		   reason = excluded.reason,
		   moderator = excluded.moderator,
		   created_at = datetime('now')`,
		[subjectType, subject, reason, moderator],
	);
}

function remove(subjectType: "wiki" | "did", subject: string): void {
	const db = getDb();
	db.run(
		"DELETE FROM moderation_actions WHERE subject_type = ? AND subject = ?",
		[subjectType, subject],
	);
}

export function hideWiki(
	atUri: string,
	reason: string | null,
	moderator: string | null,
): void {
	upsert("wiki", atUri, reason, moderator);
}

export function unhideWiki(atUri: string): void {
	remove("wiki", atUri);
}

export function banDid(
	did: string,
	reason: string | null,
	moderator: string | null,
): void {
	upsert("did", did, reason, moderator);
}

export function unbanDid(did: string): void {
	remove("did", did);
}

export function isWikiHidden(wiki: Pick<WikiRow, "at_uri" | "did">): boolean {
	const db = getDb();
	const row = db
		.query(
			`SELECT 1 FROM moderation_actions
			 WHERE (subject_type = 'wiki' AND subject = ?)
			    OR (subject_type = 'did' AND subject = ?)
			 LIMIT 1`,
		)
		.get(wiki.at_uri, wiki.did);
	return row !== null;
}

export function isDidBanned(did: string): boolean {
	const db = getDb();
	const row = db
		.query(
			"SELECT 1 FROM moderation_actions WHERE subject_type = 'did' AND subject = ?",
		)
		.get(did);
	return row !== null;
}

export function listModeration(): ModerationRow[] {
	const db = getDb();
	return db
		.query(
			"SELECT subject_type, subject, reason, moderator, created_at FROM moderation_actions ORDER BY created_at DESC",
		)
		.all() as ModerationRow[];
}