fix(housekeeping): address people moderation review

src/lib/services/ticket-replies.ts

@@ -19,23 +19,51 @@ export interface TicketReplyDb {
 	touchTicket(ticketId: bigint, updatedAt: Date): Promise<unknown>;
 }
 
-const MAX_UNSIGNED_BIGINT = 18_446_744_073_709_551_615n;
+export const MAX_UNSIGNED_TICKET_ID = 18_446_744_073_709_551_615n;
+
+function boundedDecimalPattern(maximum: string): RegExp {
+	const alternatives = [`[1-9]\\d{0,${maximum.length - 2}}`];
+	for (let index = 0; index < maximum.length; index += 1) {
+		const maximumDigit = Number(maximum[index]);
+		const minimumDigit = index === 0 ? 1 : 0;
+		const upperDigit = maximumDigit - 1;
+		if (upperDigit < minimumDigit) continue;
+		const digit =
+			upperDigit === minimumDigit
+				? String(minimumDigit)
+				: `[${minimumDigit}-${upperDigit}]`;
+		alternatives.push(
+			`${maximum.slice(0, index)}${digit}\\d{${maximum.length - index - 1}}`,
+		);
+	}
+	alternatives.push(maximum);
+	return new RegExp(`^(?:${alternatives.join("|")})$`, "u");
+}
+
+export const CANONICAL_TICKET_ID_PATTERN = boundedDecimalPattern(
+	MAX_UNSIGNED_TICKET_ID.toString(),
+);
 
 // Canonicalize a SQL BIGINT identifier without passing through Number.
 export function canonicalTicketId(value: string | number | bigint): bigint {
 	let parsed: bigint;
 	try {
-		if (
-			typeof value === "number" &&
-			(!Number.isSafeInteger(value) || value <= 0)
-		) {
+		if (typeof value === "bigint") {
+			parsed = value;
+		} else if (typeof value === "string") {
+			if (!CANONICAL_TICKET_ID_PATTERN.test(value)) {
+				throw new Error("noncanonical identifier");
+			}
+			parsed = BigInt(value);
+		} else if (Number.isSafeInteger(value) && value > 0) {
+			parsed = BigInt(value);
+		} else {
 			throw new Error("unsafe identifier");
 		}
-		parsed = BigInt(String(value));
 	} catch {
 		throw new Error("invalid ticket identifier");
 	}
-	if (parsed <= 0n || parsed > MAX_UNSIGNED_BIGINT) {
+	if (parsed <= 0n || parsed > MAX_UNSIGNED_TICKET_ID) {
 		throw new Error("invalid ticket identifier");
 	}
 	return parsed;