fix(polls): enforce shared persistence invariants

src/actions/polls.test.ts

@@ -6,6 +6,9 @@ const database = vi.hoisted(() => {
 	let mutationSteps: string[] = [];
 	let validationVoteQuestionIds: number[] = [];
 	let insertedVoteQuestionIds: number[] = [];
+	let readScopes: Array<{ table: string; transaction: boolean }> = [];
+	let transactionActive = false;
+	let insertFailure: unknown;
 
 	const nextSelected = () => selectedQueue.shift() ?? [];
 	const conditionPart = (condition: unknown, key: "column" | "value") => {
@@ -20,7 +23,10 @@ const database = vi.hoisted(() => {
 		from: vi.fn((table: { tableName?: string }) => ({
 			where: vi.fn((condition: unknown) => {
 				const tableName = table.tableName ?? "unknown";
-				const run = async () => nextSelected();
+				const run = async () => {
+					readScopes.push({ table: tableName, transaction: transactionActive });
+					return nextSelected();
+				};
 				return {
 					limit: vi.fn(async () => {
 						if (tableName === "WebsitePollVote") {
@@ -64,6 +70,7 @@ const database = vi.hoisted(() => {
 	const update = vi.fn(() => ({ set: updateSet }));
 	const insert = vi.fn((table: { tableName?: string }) => ({
 		values: vi.fn(async (values: Record<string, unknown>) => {
+			if (insertFailure !== undefined) throw insertFailure;
 			mutationSteps.push(`insert:${table.tableName ?? "unknown"}`);
 			if (table.tableName === "WebsitePollVote") {
 				insertedVoteQuestionIds.push(Number(values.questionId));
@@ -76,12 +83,19 @@ const database = vi.hoisted(() => {
 			mutationSteps.push(`delete:${table.tableName ?? "unknown"}`);
 		}),
 	}));
-	const tx = { select, insert, delete: deleteFrom };
+	const tx = { select, update, insert, delete: deleteFrom };
 	const transaction = vi.fn(
 		async (
 			run: (transaction: typeof tx) => Promise<unknown>,
 			_config?: unknown,
-		) => run(tx),
+		) => {
+			transactionActive = true;
+			try {
+				return await run(tx);
+			} finally {
+				transactionActive = false;
+			}
+		},
 	);
 
 	return {
@@ -95,17 +109,25 @@ const database = vi.hoisted(() => {
 		mutationSteps: () => [...mutationSteps],
 		validationVoteQuestionIds: () => [...validationVoteQuestionIds],
 		insertedVoteQuestionIds: () => [...insertedVoteQuestionIds],
+		readScopes: () => [...readScopes],
+		failInsertWith(error: unknown) {
+			insertFailure = error;
+		},
 		reset() {
 			selectedQueue = [];
 			mutationSteps = [];
 			validationVoteQuestionIds = [];
 			insertedVoteQuestionIds = [];
+			readScopes = [];
+			transactionActive = false;
+			insertFailure = undefined;
 		},
 	};
 });
 
 vi.mock("drizzle-orm", () => ({
 	and: vi.fn((...clauses: unknown[]) => ({ operator: "and", clauses })),
+	count: vi.fn(() => "count"),
 	eq: vi.fn((column: unknown, value: unknown) => ({
 		operator: "eq",
 		column,
@@ -182,6 +204,7 @@ vi.mock("@/lib/safe-action-shared", () => ({
 }));
 
 import {
+	addPollQuestion,
 	deletePoll,
 	updatePoll,
 	updatePollQuestion,
@@ -217,6 +240,52 @@ describe("poll update merge validation", () => {
 		expect(database.updateSet).not.toHaveBeenCalled();
 	});
 
+	it("rejects legacy activation above the public 50-question batch limit", async () => {
+		database.queueSelected(
+			[
+				{
+					id: 1,
+					title: "Schedule",
+					description: null,
+					status: "draft",
+					showResults: 1,
+					multipleChoice: 0,
+					startsAt: null,
+					endsAt: null,
+				},
+			],
+			[{ value: 51 }],
+		);
+
+		const result = await updatePoll({ id: 1, status: "active" });
+
+		expect(result).toEqual({
+			ok: false,
+			error: "Poll cannot be activated with more than 50 questions",
+		});
+		expect(database.updateSet).not.toHaveBeenCalled();
+		expect(database.transaction).toHaveBeenCalledWith(expect.any(Function), {
+			isolationLevel: "read committed",
+		});
+	});
+
+	it("rejects legacy question 51 while the parent poll is active", async () => {
+		database.queueSelected([{ id: 1, status: "active" }], [{ value: 50 }]);
+
+		const result = await addPollQuestion({
+			pollId: 1,
+			question: "Question 51",
+			type: "single",
+			options: "Yes\nNo",
+		});
+
+		expect(result).toEqual({
+			ok: false,
+			error: "Poll question limit reached",
+		});
+		expect(database.insertedVoteQuestionIds()).toEqual([]);
+	});
+
 	it("rejects a partial options patch for a persisted text question without updating", async () => {
 		database.queueSelected([
 			{
@@ -233,6 +302,54 @@ describe("poll update merge validation", () => {
 		expect(result).toEqual({ ok: false, error: "Invalid poll question" });
 		expect(database.updateSet).not.toHaveBeenCalled();
 	});
+
+	it("rejects semantic edits to a legacy question after votes exist", async () => {
+		database.queueSelected(
+			[
+				{
+					id: 1,
+					pollId: 1,
+					question: "Why?",
+					type: "text",
+					sortOrder: 0,
+					options: "",
+				},
+			],
+			[{ id: 91 }],
+		);
+
+		const result = await updatePollQuestion({ id: 1, question: "Why now?" });
+
+		expect(result).toEqual({
+			ok: false,
+			error: "A voted question can only be reordered",
+		});
+		expect(database.updateSet).not.toHaveBeenCalled();
+	});
+
+	it("allows a sort-order-only legacy edit after votes exist", async () => {
+		database.queueSelected(
+			[
+				{
+					id: 1,
+					pollId: 1,
+					question: "Why?",
+					type: "text",
+					sortOrder: 0,
+					options: "",
+				},
+			],
+			[{ id: 91 }],
+		);
+
+		const result = await updatePollQuestion({ id: 1, sortOrder: 2 });
+
+		expect(result).toEqual({ ok: true, data: { id: 1 } });
+		expect(database.updateSet).toHaveBeenCalledWith({ sortOrder: 2 });
+		expect(database.mutationSteps()).toContain(
+			"lock:WebsitePollQuestion:eq:id:1:update",
+		);
+	});
 });
 
 describe("poll transaction lock order", () => {
@@ -261,7 +378,7 @@ describe("poll transaction lock order", () => {
 		]);
 	});
 
-	it("validates votes in request order but inserts a sorted copy", async () => {
+	it("locks and validates current vote state in one transaction before sorted inserts", async () => {
 		database.queueSelected(
 			[
 				{
@@ -271,10 +388,9 @@ describe("poll transaction lock order", () => {
 					endsAt: null,
 				},
 			],
-			[
-				{ id: 9, pollId: 7, type: "single", options: "A\nB" },
-				{ id: 4, pollId: 7, type: "single", options: "A\nB" },
-			],
+			[{ id: 4 }, { id: 9 }],
+			[{ id: 4, pollId: 7, type: "single", options: "A\nB" }],
+			[{ id: 9, pollId: 7, type: "single", options: "A\nB" }],
 			[],
 			[],
 		);
@@ -292,5 +408,52 @@ describe("poll transaction lock order", () => {
 		expect(database.validationVoteQuestionIds()).toEqual([9, 4]);
 		expect(database.insertedVoteQuestionIds()).toEqual([4, 9]);
 		expect(input.votes.map(({ questionId }) => questionId)).toEqual([9, 4]);
+		expect(database.readScopes().every((read) => read.transaction)).toBe(true);
+		expect(database.mutationSteps().slice(0, 4)).toEqual([
+			"lock:WebsitePoll:eq:id:7:update",
+			"read:WebsitePollQuestion:eq:pollId:orderBy:id",
+			"lock:WebsitePollQuestion:eq:id:4:update",
+			"lock:WebsitePollQuestion:eq:id:9:update",
+		]);
+	});
+
+	it("rechecks a poll closure atomically before inserting votes", async () => {
+		database.queueSelected([
+			{ id: 7, status: "closed", startsAt: null, endsAt: null },
+		]);
+
+		const result = await voteOnPoll({
+			pollId: 7,
+			votes: [{ questionId: 4, answer: "A" }],
+		});
+
+		expect(result).toEqual({
+			ok: false,
+			error: "This poll is not open for voting",
+		});
+		expect(database.insertedVoteQuestionIds()).toEqual([]);
+		expect(database.readScopes()).toEqual([
+			{ table: "WebsitePoll", transaction: true },
+		]);
+	});
+
+	it("maps a duplicate-key insert race to the existing duplicate response", async () => {
+		database.queueSelected(
+			[{ id: 7, status: "active", startsAt: null, endsAt: null }],
+			[{ id: 4 }],
+			[{ id: 4, pollId: 7, type: "single", options: "A\nB" }],
+			[],
+		);
+		database.failInsertWith({ code: "ER_DUP_ENTRY" });
+
+		const result = await voteOnPoll({
+			pollId: 7,
+			votes: [{ questionId: 4, answer: "A" }],
+		});
+
+		expect(result).toEqual({
+			ok: false,
+			error: "You have already voted on this poll",
+		});
 	});
 });

src/actions/polls.ts

@@ -1,6 +1,6 @@
 "use server";
 
-import { and, eq, inArray } from "drizzle-orm";
+import { and, count, eq, inArray } from "drizzle-orm";
 import { revalidatePath } from "next/cache";
 import { z } from "zod";
 import {
@@ -11,12 +11,21 @@ import {
 } from "@/lib/db";
 import { PERMS } from "@/lib/permissions";
 import {
+	hasPollQuestionSemanticChange,
+	POLL_PUBLIC_QUESTION_LIMIT,
 	type PollQuestionType,
 	parsePollAnswerSelections,
 	parsePollOptions,
+	pollQuestionLimitReached,
+	serializePollOptions,
 } from "@/lib/polls/poll-semantics";
 import { adminAction, authAction } from "@/lib/safe-action";
-import { ActionError, actionError, actionOk } from "@/lib/safe-action-shared";
+import {
+	ActionError,
+	type ActionResult,
+	actionError,
+	actionOk,
+} from "@/lib/safe-action-shared";
 import { logAudit } from "@/lib/services/audit";
 import {
 	createPollSchema,
@@ -56,28 +65,45 @@ export const updatePoll = adminAction(
 	{ permission: PERMS.POLLS_EDIT, schema: updatePollInput },
 	async (ctx) => {
 		const { id, ...data } = ctx.data;
-		const [existing] = await db
-			.select({
-				id: WebsitePoll.id,
-				title: WebsitePoll.title,
-				description: WebsitePoll.description,
-				status: WebsitePoll.status,
-				showResults: WebsitePoll.showResults,
-				multipleChoice: WebsitePoll.multipleChoice,
-				startsAt: WebsitePoll.startsAt,
-				endsAt: WebsitePoll.endsAt,
-			})
-			.from(WebsitePoll)
-			.where(eq(WebsitePoll.id, id))
-			.limit(1);
-		if (!existing) throw new ActionError("Poll not found");
-		const merged = createPollSchema.safeParse({ ...existing, ...data });
-		if (!merged.success) throw new ActionError("Invalid poll schedule");
-
-		await db
-			.update(WebsitePoll)
-			.set({ ...data, updatedAt: new Date() })
-			.where(eq(WebsitePoll.id, id));
+		const existing = await db.transaction(
+			async (tx) => {
+				const [poll] = await tx
+					.select({
+						id: WebsitePoll.id,
+						title: WebsitePoll.title,
+						description: WebsitePoll.description,
+						status: WebsitePoll.status,
+						showResults: WebsitePoll.showResults,
+						multipleChoice: WebsitePoll.multipleChoice,
+						startsAt: WebsitePoll.startsAt,
+						endsAt: WebsitePoll.endsAt,
+					})
+					.from(WebsitePoll)
+					.where(eq(WebsitePoll.id, id))
+					.for("update");
+				if (!poll) throw new ActionError("Poll not found");
+				const merged = createPollSchema.safeParse({ ...poll, ...data });
+				if (!merged.success) throw new ActionError("Invalid poll schedule");
+				if (merged.data.status === "active") {
+					const [questionCount] = await tx
+						.select({ value: count() })
+						.from(WebsitePollQuestion)
+						.where(eq(WebsitePollQuestion.pollId, id))
+						.limit(1);
+					if (Number(questionCount?.value ?? 0) > POLL_PUBLIC_QUESTION_LIMIT) {
+						throw new ActionError(
+							"Poll cannot be activated with more than 50 questions",
+						);
+					}
+				}
+				await tx
+					.update(WebsitePoll)
+					.set({ ...data, updatedAt: new Date() })
+					.where(eq(WebsitePoll.id, id));
+				return poll;
+			},
+			{ isolationLevel: "read committed" },
+		);
 		logAudit({
 			userId: ctx.session.user.id,
 			action: "poll_update",
@@ -150,7 +176,34 @@ export const deletePoll = adminAction(
 export const addPollQuestion = adminAction(
 	{ permission: PERMS.POLLS_EDIT, schema: pollQuestionSchema },
 	async (ctx) => {
-		const [result] = await db.insert(WebsitePollQuestion).values(ctx.data);
+		const [result] = await db.transaction(
+			async (tx) => {
+				const [parent] = await tx
+					.select({ id: WebsitePoll.id, status: WebsitePoll.status })
+					.from(WebsitePoll)
+					.where(eq(WebsitePoll.id, ctx.data.pollId))
+					.for("update");
+				if (!parent) throw new ActionError("Poll not found");
+				const [questionCount] = await tx
+					.select({ value: count() })
+					.from(WebsitePollQuestion)
+					.where(eq(WebsitePollQuestion.pollId, parent.id))
+					.limit(1);
+				if (
+					pollQuestionLimitReached(
+						parent.status,
+						Number(questionCount?.value ?? 0),
+					)
+				) {
+					throw new ActionError("Poll question limit reached");
+				}
+				return tx.insert(WebsitePollQuestion).values({
+					...ctx.data,
+					options: serializePollOptions(ctx.data.type, ctx.data.options),
+				});
+			},
+			{ isolationLevel: "read committed" },
+		);
 		return actionOk({ id: Number(result.insertId) });
 	},
 );
@@ -163,25 +216,59 @@ export const updatePollQuestion = adminAction(
 	{ permission: PERMS.POLLS_EDIT, schema: updateQuestionInput },
 	async (ctx) => {
 		const { id, ...data } = ctx.data;
-		const [existing] = await db
-			.select({
-				pollId: WebsitePollQuestion.pollId,
-				question: WebsitePollQuestion.question,
-				type: WebsitePollQuestion.type,
-				sortOrder: WebsitePollQuestion.sortOrder,
-				options: WebsitePollQuestion.options,
-			})
-			.from(WebsitePollQuestion)
-			.where(eq(WebsitePollQuestion.id, id))
-			.limit(1);
-		if (!existing) throw new ActionError("Poll question not found");
-		const merged = pollQuestionSchema.safeParse({ ...existing, ...data });
-		if (!merged.success) throw new ActionError("Invalid poll question");
-
-		await db
-			.update(WebsitePollQuestion)
-			.set(data)
-			.where(eq(WebsitePollQuestion.id, id));
+		await db.transaction(
+			async (tx) => {
+				const [existing] = await tx
+					.select({
+						id: WebsitePollQuestion.id,
+						pollId: WebsitePollQuestion.pollId,
+						question: WebsitePollQuestion.question,
+						type: WebsitePollQuestion.type,
+						sortOrder: WebsitePollQuestion.sortOrder,
+						options: WebsitePollQuestion.options,
+					})
+					.from(WebsitePollQuestion)
+					.where(eq(WebsitePollQuestion.id, id))
+					.for("update");
+				if (!existing) throw new ActionError("Poll question not found");
+				const merged = pollQuestionSchema.safeParse({ ...existing, ...data });
+				if (!merged.success) throw new ActionError("Invalid poll question");
+				const values = {
+					...data,
+					...(Object.hasOwn(data, "options")
+						? {
+								options: serializePollOptions(
+									merged.data.type,
+									merged.data.options,
+								),
+							}
+						: {}),
+				};
+				if (
+					hasPollQuestionSemanticChange(
+						{
+							...existing,
+							type: existing.type as PollQuestionType,
+						},
+						merged.data,
+					)
+				) {
+					const [vote] = await tx
+						.select({ id: WebsitePollVote.id })
+						.from(WebsitePollVote)
+						.where(eq(WebsitePollVote.questionId, id))
+						.limit(1);
+					if (vote) {
+						throw new ActionError("A voted question can only be reordered");
+					}
+				}
+				await tx
+					.update(WebsitePollQuestion)
+					.set(values)
+					.where(eq(WebsitePollQuestion.id, id));
+			},
+			{ isolationLevel: "read committed" },
+		);
 		return actionOk({ id });
 	},
 );
@@ -193,15 +280,39 @@ const deleteQuestionInput = z.object({
 export const deletePollQuestion = adminAction(
 	{ permission: PERMS.POLLS_EDIT, schema: deleteQuestionInput },
 	async (ctx) => {
-		await db
-			.delete(WebsitePollQuestion)
-			.where(eq(WebsitePollQuestion.id, ctx.data.id));
+		await db.transaction(
+			async (tx) => {
+				const [question] = await tx
+					.select({ id: WebsitePollQuestion.id })
+					.from(WebsitePollQuestion)
+					.where(eq(WebsitePollQuestion.id, ctx.data.id))
+					.for("update");
+				if (!question) throw new ActionError("Poll question not found");
+				await tx
+					.delete(WebsitePollVote)
+					.where(eq(WebsitePollVote.questionId, question.id));
+				await tx
+					.delete(WebsitePollQuestion)
+					.where(eq(WebsitePollQuestion.id, question.id));
+			},
+			{ isolationLevel: "read committed" },
+		);
 		return actionOk();
 	},
 );
 
 // ── Public site: vote ───────────────────────────────────────────────
 
+function isDuplicateKey(error: unknown): boolean {
+	if (!error || typeof error !== "object") return false;
+	const candidate = error as { code?: string | number; errno?: number };
+	return (
+		candidate.code === "P2002" ||
+		candidate.code === "ER_DUP_ENTRY" ||
+		candidate.errno === 1062
+	);
+}
+
 export const voteOnPoll = authAction(
 	{
 		schema: voteOnPollSchema,
@@ -215,107 +326,134 @@ export const voteOnPoll = authAction(
 			return actionError("Unauthorized");
 		}
 
-		const [poll] = await db
-			.select({
-				id: WebsitePoll.id,
-				status: WebsitePoll.status,
-				startsAt: WebsitePoll.startsAt,
-				endsAt: WebsitePoll.endsAt,
-			})
-			.from(WebsitePoll)
-			.where(eq(WebsitePoll.id, ctx.data.pollId))
-			.limit(1);
+		let outcome: ActionResult<{ pollId: number }>;
+		try {
+			outcome = await db.transaction(
+				async (tx) => {
+					const [poll] = await tx
+						.select({
+							id: WebsitePoll.id,
+							status: WebsitePoll.status,
+							startsAt: WebsitePoll.startsAt,
+							endsAt: WebsitePoll.endsAt,
+						})
+						.from(WebsitePoll)
+						.where(eq(WebsitePoll.id, ctx.data.pollId))
+						.for("update");
+					if (!poll) return actionError("Poll not found");
+					if (poll.status !== "active") {
+						return actionError("This poll is not open for voting");
+					}
+					const now = Date.now();
+					if (poll.startsAt && poll.startsAt.getTime() > now) {
+						return actionError("This poll has not started yet");
+					}
+					if (poll.endsAt && poll.endsAt.getTime() < now) {
+						return actionError("This poll has ended");
+					}
 
-		if (!poll) return actionError("Poll not found");
-		if (poll.status !== "active") {
-			return actionError("This poll is not open for voting");
-		}
-		const now = Date.now();
-		if (poll.startsAt && poll.startsAt.getTime() > now) {
-			return actionError("This poll has not started yet");
-		}
-		if (poll.endsAt && poll.endsAt.getTime() < now) {
-			return actionError("This poll has ended");
-		}
+					const questionIds = await tx
+						.select({ id: WebsitePollQuestion.id })
+						.from(WebsitePollQuestion)
+						.where(eq(WebsitePollQuestion.pollId, poll.id))
+						.orderBy(WebsitePollQuestion.id);
+					const questions = [];
+					for (const questionId of questionIds) {
+						const [question] = await tx
+							.select({
+								id: WebsitePollQuestion.id,
+								pollId: WebsitePollQuestion.pollId,
+								type: WebsitePollQuestion.type,
+								options: WebsitePollQuestion.options,
+							})
+							.from(WebsitePollQuestion)
+							.where(eq(WebsitePollQuestion.id, questionId.id))
+							.for("update");
+						if (question) questions.push(question);
+					}
 
-		const questions = await db
-			.select({
-				id: WebsitePollQuestion.id,
-				pollId: WebsitePollQuestion.pollId,
-				type: WebsitePollQuestion.type,
-				options: WebsitePollQuestion.options,
-			})
-			.from(WebsitePollQuestion)
-			.where(eq(WebsitePollQuestion.pollId, poll.id));
+					const questionById = new Map(
+						questions.map((question) => [question.id, question]),
+					);
+					const seen = new Set<number>();
+					const normalizedAnswers = new Map<number, string>();
 
-		const questionById = new Map(questions.map((q) => [q.id, q]));
-		const seen = new Set<number>();
+					for (const vote of ctx.data.votes) {
+						if (seen.has(vote.questionId)) {
+							return actionError("Duplicate vote for the same question");
+						}
+						seen.add(vote.questionId);
 
-		for (const vote of ctx.data.votes) {
-			if (seen.has(vote.questionId)) {
-				return actionError("Duplicate vote for the same question");
-			}
-			seen.add(vote.questionId);
+						const question = questionById.get(vote.questionId);
+						if (!question || question.pollId !== poll.id) {
+							return actionError("Invalid question for this poll");
+						}
 
-			const question = questionById.get(vote.questionId);
-			if (!question || question.pollId !== poll.id) {
-				return actionError("Invalid question for this poll");
-			}
+						const answer = vote.answer.trim();
+						if (!answer) return actionError("Answer is required");
+						const options = parsePollOptions(question.options);
+						const selected = parsePollAnswerSelections(
+							question.type as PollQuestionType,
+							answer,
+						);
 
-			const answer = vote.answer.trim();
-			if (!answer) return actionError("Answer is required");
+						if (question.type === "text") {
+							normalizedAnswers.set(vote.questionId, answer);
+						} else if (question.type === "multiple") {
+							if (selected.length === 0) {
+								return actionError("Select at least one option");
+							}
+							if (selected.some((selection) => !options.includes(selection))) {
+								return actionError("Invalid option selected");
+							}
+							normalizedAnswers.set(vote.questionId, selected.join("\n"));
+						} else {
+							const selectedOption = selected[0] ?? "";
+							if (!options.includes(selectedOption)) {
+								return actionError("Invalid option selected");
+							}
+							normalizedAnswers.set(vote.questionId, selectedOption);
+						}
 
-			const options = parsePollOptions(question.options);
-			const selected = parsePollAnswerSelections(
-				question.type as PollQuestionType,
-				answer,
+						const [existing] = await tx
+							.select({ id: WebsitePollVote.id })
+							.from(WebsitePollVote)
+							.where(
+								and(
+									eq(WebsitePollVote.questionId, vote.questionId),
+									eq(WebsitePollVote.userId, userId),
+								),
+							)
+							.limit(1);
+						if (existing) {
+							return actionError("You have already voted on this poll");
+						}
+					}
+
+					const votesToInsert = [...ctx.data.votes].sort(
+						(left, right) => left.questionId - right.questionId,
+					);
+					for (const vote of votesToInsert) {
+						await tx.insert(WebsitePollVote).values({
+							questionId: vote.questionId,
+							userId,
+							answer: normalizedAnswers.get(vote.questionId) ?? "",
+						});
+					}
+					return actionOk({ pollId: poll.id });
+				},
+				{ isolationLevel: "read committed" },
 			);
-
-			if (question.type === "text") {
-				if (answer.length > 500) {
-					return actionError("Answer is too long");
-				}
-			} else if (question.type === "multiple") {
-				if (selected.length === 0) {
-					return actionError("Select at least one option");
-				}
-				if (selected.some((selection) => !options.includes(selection))) {
-					return actionError("Invalid option selected");
-				}
-			} else if (!options.includes(selected[0] ?? "")) {
-				return actionError("Invalid option selected");
-			}
-
-			const [existing] = await db
-				.select({ id: WebsitePollVote.id })
-				.from(WebsitePollVote)
-				.where(
-					and(
-						eq(WebsitePollVote.questionId, vote.questionId),
-						eq(WebsitePollVote.userId, userId),
-					),
-				)
-				.limit(1);
-			if (existing) {
+		} catch (error) {
+			if (isDuplicateKey(error)) {
 				return actionError("You have already voted on this poll");
 			}
+			throw error;
 		}
-
-		const votesToInsert = [...ctx.data.votes].sort(
-			(left, right) => left.questionId - right.questionId,
-		);
-		await db.transaction(async (tx) => {
-			for (const vote of votesToInsert) {
-				await tx.insert(WebsitePollVote).values({
-					questionId: vote.questionId,
-					userId,
-					answer: vote.answer.trim(),
-				});
-			}
-		});
+		if (!outcome.ok) return outcome;
 
 		revalidatePath("/polls");
-		revalidatePath(`/polls/${poll.id}`);
-		return actionOk({ pollId: poll.id });
+		revalidatePath(`/polls/${ctx.data.pollId}`);
+		return outcome;
 	},
 );

src/features/housekeeping/domains/content/services/mutation-runtime-database.test.ts

@@ -486,14 +486,17 @@ describe("Content database mutation runtime partial updates", () => {
 	});
 
 	it("canonicalizes submitted question options and preserves omitted columns", async () => {
-		database.selected({
-			id: 7,
-			pollId: 3,
-			question: "Favourite colour?",
-			type: "single",
-			sortOrder: 0,
-			options: "Red\nBlue",
-		});
+		database.queueSelected(
+			{
+				id: 7,
+				pollId: 3,
+				question: "Favourite colour?",
+				type: "single",
+				sortOrder: 0,
+				options: "Red\nBlue",
+			},
+			[],
+		);
 
 		await executeContentDatabaseMutation(
 			"poll-question.change",
@@ -508,6 +511,53 @@ describe("Content database mutation runtime partial updates", () => {
 		]);
 	});
 
+	it("rejects semantic question edits after votes exist", async () => {
+		database.queueSelected(
+			{
+				id: 7,
+				pollId: 3,
+				question: "Favourite colour?",
+				type: "single",
+				sortOrder: 0,
+				options: "Red\nBlue",
+			},
+			{ id: 91 },
+		);
+
+		await expect(
+			executeContentDatabaseMutation(
+				"poll-question.change",
+				{ action: "update", id: 7, options: "Green\nYellow" },
+				context,
+				undefined,
+			),
+		).rejects.toMatchObject({ code: "CONFLICT" });
+		expect(database.set).not.toHaveBeenCalled();
+	});
+
+	it("allows sort-order-only question edits after votes exist", async () => {
+		database.queueSelected(
+			{
+				id: 7,
+				pollId: 3,
+				question: "Favourite colour?",
+				type: "single",
+				sortOrder: 0,
+				options: "Red\nBlue",
+			},
+			{ id: 91 },
+		);
+
+		await executeContentDatabaseMutation(
+			"poll-question.change",
+			{ action: "update", id: 7, sortOrder: 2 },
+			context,
+			undefined,
+		);
+
+		expect(database.set).toHaveBeenCalledWith({ sortOrder: 2 });
+	});
+
 	it("blocks deletion of an event type referenced by an event", async () => {
 		database.queueSelected({ id: 7, name: "Tournament" }, { id: 11 });
 

src/features/housekeeping/domains/content/services/mutation-runtime-database.ts

@@ -26,7 +26,13 @@ import {
 } from "@/lib/db";
 import { slugify } from "@/lib/format";
 import { canonicalize } from "@/lib/foundation/security";
-import { serializePollOptions } from "@/lib/polls/poll-semantics";
+import {
+	hasPollQuestionSemanticChange,
+	POLL_PUBLIC_QUESTION_LIMIT,
+	type PollQuestionType,
+	pollQuestionLimitReached,
+	serializePollOptions,
+} from "@/lib/polls/poll-semantics";
 import { logStaffActivity } from "@/lib/services/staff-activity";
 import {
 	createEventSchema,
@@ -682,7 +688,7 @@ async function pollChange(
 	if (!merged.success) throw validation(merged.error);
 	if (
 		merged.data.status === "active" &&
-		(await pollQuestionCount(connection, id)) > 50
+		(await pollQuestionCount(connection, id)) > POLL_PUBLIC_QUESTION_LIMIT
 	) {
 		throw conflict();
 	}
@@ -713,10 +719,7 @@ async function pollQuestionChange(
 			.for("update");
 		if (!parent) throw notFound();
 		const questionCount = await pollQuestionCount(connection, pollId);
-		if (
-			questionCount >= 100 ||
-			(parent.status === "active" && questionCount >= 50)
-		) {
+		if (pollQuestionLimitReached(parent.status, questionCount)) {
 			throw conflict();
 		}
 		const parsed = pollQuestionSchema.safeParse(data);
@@ -783,6 +786,19 @@ async function pollQuestionChange(
 			merged.data.options,
 		);
 	}
+	if (
+		hasPollQuestionSemanticChange(
+			{ ...existing, type: existing.type as PollQuestionType },
+			merged.data,
+		)
+	) {
+		const [vote] = await connection
+			.select({ id: WebsitePollVote.id })
+			.from(WebsitePollVote)
+			.where(eq(WebsitePollVote.questionId, id))
+			.limit(1);
+		if (vote) throw conflict();
+	}
 	await connection
 		.update(WebsitePollQuestion)
 		.set(values)

src/lib/polls/poll-semantics.ts

@@ -1,5 +1,8 @@
 export const POLL_QUESTION_TYPES = ["single", "multiple", "text"] as const;
 export type PollQuestionType = (typeof POLL_QUESTION_TYPES)[number];
+export const POLL_PUBLIC_QUESTION_LIMIT = 50;
+export const POLL_DRAFT_QUESTION_LIMIT = 100;
+export const POLL_ANSWER_MAX_LENGTH = 500;
 
 export function parsePollOptions(value: string): string[] {
 	return value
@@ -24,3 +27,33 @@ export function parsePollAnswerSelections(
 		? parsePollOptions(normalized)
 		: [normalized.trim()].filter(Boolean);
 }
+
+export function pollQuestionLimitReached(
+	status: string,
+	currentCount: number,
+): boolean {
+	const limit =
+		status === "active"
+			? POLL_PUBLIC_QUESTION_LIMIT
+			: POLL_DRAFT_QUESTION_LIMIT;
+	return currentCount >= limit;
+}
+
+interface PollQuestionSemantics {
+	readonly question: string;
+	readonly type: PollQuestionType;
+	readonly options: string;
+}
+
+export function hasPollQuestionSemanticChange(
+	before: PollQuestionSemantics,
+	after: PollQuestionSemantics,
+): boolean {
+	return (
+		before.question.normalize("NFC").trim() !==
+			after.question.normalize("NFC").trim() ||
+		before.type !== after.type ||
+		serializePollOptions(before.type, before.options) !==
+			serializePollOptions(after.type, after.options)
+	);
+}

src/lib/validators/poll.test.ts

@@ -112,6 +112,50 @@ describe("pollQuestionSchema", () => {
 			}).success,
 		).toBe(false);
 	});
+
+	it("keeps every single-choice option compatible with the public answer limit", () => {
+		const exactly500 = `A${"x".repeat(499)}`;
+		const tooLong = `B${"x".repeat(500)}`;
+
+		expect(
+			pollQuestionSchema.safeParse({
+				pollId: 1,
+				question: "Boundary?",
+				type: "single",
+				options: `${exactly500}\nShort`,
+			}).success,
+		).toBe(true);
+		expect(
+			pollQuestionSchema.safeParse({
+				pollId: 1,
+				question: "Boundary?",
+				type: "single",
+				options: `${tooLong}\nShort`,
+			}).success,
+		).toBe(false);
+	});
+
+	it("bounds the possible serialized multiple-choice answer at 500 characters", () => {
+		const exactly500 = `${"A".repeat(249)}\n${"B".repeat(250)}`;
+		const tooLong = `${"A".repeat(250)}\n${"B".repeat(250)}`;
+
+		expect(
+			pollQuestionSchema.safeParse({
+				pollId: 1,
+				question: "Boundary?",
+				type: "multiple",
+				options: exactly500,
+			}).success,
+		).toBe(true);
+		expect(
+			pollQuestionSchema.safeParse({
+				pollId: 1,
+				question: "Boundary?",
+				type: "multiple",
+				options: tooLong,
+			}).success,
+		).toBe(false);
+	});
 });
 describe("poll schedule validation", () => {
 	it("requires the end time to be later than the start time", () => {
@@ -145,6 +189,17 @@ describe("pollVoteSchema", () => {
 			pollVoteSchema.safeParse({ questionId: 0, answer: "x" }).success,
 		).toBe(false);
 	});
+
+	it("accepts 500 characters and rejects 501", () => {
+		expect(
+			pollVoteSchema.safeParse({ questionId: 5, answer: "A".repeat(500) })
+				.success,
+		).toBe(true);
+		expect(
+			pollVoteSchema.safeParse({ questionId: 5, answer: "A".repeat(501) })
+				.success,
+		).toBe(false);
+	});
 });
 
 describe("voteOnPollSchema", () => {

src/lib/validators/poll.ts

@@ -1,5 +1,6 @@
 import { z } from "zod";
 import {
+	POLL_ANSWER_MAX_LENGTH,
 	POLL_QUESTION_TYPES,
 	parsePollOptions,
 } from "@/lib/polls/poll-semantics";
@@ -7,9 +8,9 @@ import {
 const pollFields = z.object({
 	title: z.string().trim().min(1, "Title is required").max(255),
 	description: z.string().max(2_000).nullable().optional(),
-	status: z.enum(["draft", "active", "closed"]).default("draft"),
-	showResults: z.coerce.number().int().min(0).max(1).default(1),
-	multipleChoice: z.coerce.number().int().min(0).max(1).default(0),
+	status: z.enum(["draft", "active", "closed"]),
+	showResults: z.coerce.number().int().min(0).max(1),
+	multipleChoice: z.coerce.number().int().min(0).max(1),
 	startsAt: z.coerce.date().nullable().optional(),
 	endsAt: z.coerce.date().nullable().optional(),
 });
@@ -27,7 +28,13 @@ function validateSchedule(
 	}
 }
 
-export const createPollSchema = pollFields.superRefine(validateSchedule);
+export const createPollSchema = pollFields
+	.extend({
+		status: pollFields.shape.status.default("draft"),
+		showResults: pollFields.shape.showResults.default(1),
+		multipleChoice: pollFields.shape.multipleChoice.default(0),
+	})
+	.superRefine(validateSchedule);
 export const updatePollSchema = pollFields
 	.partial()
 	.superRefine(validateSchedule);
@@ -35,9 +42,9 @@ export const updatePollSchema = pollFields
 const pollQuestionFields = z.object({
 	pollId: z.coerce.number().int().positive(),
 	question: z.string().trim().min(1).max(500),
-	type: z.enum(POLL_QUESTION_TYPES).default("single"),
-	sortOrder: z.coerce.number().int().min(0).default(0),
-	options: z.string().max(20_000).default(""),
+	type: z.enum(POLL_QUESTION_TYPES),
+	sortOrder: z.coerce.number().int().min(0),
+	options: z.string().max(20_000),
 });
 
 function validateQuestionOptions(
@@ -70,18 +77,42 @@ function validateQuestionOptions(
 			path: ["options"],
 			message: "At most 100 options are allowed",
 		});
+	if (
+		data.type !== "text" &&
+		options.some((option) => option.length > POLL_ANSWER_MAX_LENGTH)
+	) {
+		context.addIssue({
+			code: "custom",
+			path: ["options"],
+			message: "Each option must fit the public answer limit",
+		});
+	}
+	if (
+		data.type === "multiple" &&
+		options.join("\n").length > POLL_ANSWER_MAX_LENGTH
+	) {
+		context.addIssue({
+			code: "custom",
+			path: ["options"],
+			message: "All selected options must fit the public answer limit",
+		});
+	}
 }
 
-export const pollQuestionSchema = pollQuestionFields.superRefine(
-	validateQuestionOptions,
-);
+export const pollQuestionSchema = pollQuestionFields
+	.extend({
+		type: pollQuestionFields.shape.type.default("single"),
+		sortOrder: pollQuestionFields.shape.sortOrder.default(0),
+		options: pollQuestionFields.shape.options.default(""),
+	})
+	.superRefine(validateQuestionOptions);
 export const pollQuestionPatchSchema = pollQuestionFields
 	.omit({ pollId: true })
 	.partial();
 
 export const pollVoteSchema = z.object({
 	questionId: z.coerce.number().int().positive(),
-	answer: z.string().min(1).max(500),
+	answer: z.string().min(1).max(POLL_ANSWER_MAX_LENGTH),
 });
 
 export const voteOnPollSchema = z.object({