refactor(effect): migrate svelte json hotspots to typed decoders

4 files changed, 79 insertions, 21 deletions

diff --git a/src/lib/Effect/json.test.ts b/src/lib/Effect/json.test.ts
index b315fe61..c13824fe 100644
--- a/src/lib/Effect/json.test.ts
+++ b/src/lib/Effect/json.test.ts
@@ -2,7 +2,9 @@ import { describe, expect, it } from "vitest";
 import {
 	parseJsonStringOrDefault,
 	parseJsonStringOrThrow,
+	parseJsonStringWithSchemaOrDefault,
 } from "$lib/Effect/json";
+import { Schema } from "effect";
 
 describe("effect json parsing", () => {
 	it("parses valid json strings", () => {
@@ -21,4 +23,21 @@ describe("effect json parsing", () => {
 			ok: false,
 		});
 	});
+
+	it("decodes json with a schema and returns fallback on schema mismatch", () => {
+		expect(
+			parseJsonStringWithSchemaOrDefault(
+				"[1,2,3]",
+				Schema.Array(Schema.Number),
+				[],
+			),
+		).toEqual([1, 2, 3]);
+		expect(
+			parseJsonStringWithSchemaOrDefault(
+				`["a",2]`,
+				Schema.Array(Schema.Number),
+				[],
+			),
+		).toEqual([]);
+	});
 });
diff --git a/src/lib/Effect/json.ts b/src/lib/Effect/json.ts
index b905cc41..24414fb0 100644
--- a/src/lib/Effect/json.ts
+++ b/src/lib/Effect/json.ts
@@ -1,4 +1,8 @@
-import { Effect, Result } from "effect";
+import { Effect, Result, Schema } from "effect";
+
+type SyncDecodingSchema = Schema.Top & {
+	readonly DecodingServices: never;
+};
 
 export const parseJsonStringEffect = (value: string) =>
 	Effect.try({
@@ -26,3 +30,28 @@ export const parseJsonStringOrDefault = <T>(value: string, fallback: T): T => {
 		onFailure: () => fallback,
 	});
 };
+
+export const parseJsonStringWithSchemaOrDefault = <
+	S extends SyncDecodingSchema,
+>(
+	value: string,
+	schema: S,
+	fallback: S["Type"],
+): S["Type"] => {
+	const parsed = parseJsonStringEither(value);
+
+	return Result.match(parsed, {
+		onSuccess: (decoded) => {
+			const decodedWithSchema = Result.try({
+				try: () => Schema.decodeUnknownSync(schema)(decoded),
+				catch: () => fallback,
+			});
+
+			return Result.match(decodedWithSchema, {
+				onSuccess: (value) => value,
+				onFailure: () => fallback,
+			});
+		},
+		onFailure: () => fallback,
+	});
+};
diff --git a/src/lib/Events/AniListBadges/EasterEvent2025/EasterEgg.svelte b/src/lib/Events/AniListBadges/EasterEvent2025/EasterEgg.svelte
index ab9698d4..c48003d7 100644
--- a/src/lib/Events/AniListBadges/EasterEvent2025/EasterEgg.svelte
+++ b/src/lib/Events/AniListBadges/EasterEvent2025/EasterEgg.svelte
@@ -2,16 +2,24 @@
 import { onMount, tick } from "svelte";
 import { browser } from "$app/environment";
 import Popup from "$lib/Layout/Popup.svelte";
+import { parseJsonStringWithSchemaOrDefault } from "$lib/Effect/json";
+import { Schema } from "effect";
 
 export let targetID = "easter-target";
 export let id: number;
 
 let visible = false;
 let showPopup = false;
+const clickedEggsSchema = Schema.Array(Schema.Number);
+const readClickedEggs = () => [
+	...parseJsonStringWithSchemaOrDefault(
+		localStorage.getItem("easter2025ClickedEggs") || "[]",
+		clickedEggsSchema,
+		[],
+	),
+];
 
-$: eggCount = browser
-	? JSON.parse(localStorage.getItem("easter2025ClickedEggs") || "[]").length
-	: 0;
+$: eggCount = browser ? readClickedEggs().length : 0;
 
 onMount(() => {
 	let intervalId: number | undefined;
@@ -23,8 +31,7 @@ onMount(() => {
 
 		if (!targetElement) return;
 
-		const storedClickedEggs = localStorage.getItem("easter2025ClickedEggs");
-		const clickedEggs = storedClickedEggs ? JSON.parse(storedClickedEggs) : [];
+		const clickedEggs = readClickedEggs();
 		const eggVisual = document.getElementById(`egg-visual-${targetID}-${id}`);
 		const eggClick = document.getElementById(`egg-click-${targetID}-${id}`);
 		const pageWidth = document.documentElement.clientWidth;
@@ -60,8 +67,7 @@ onMount(() => {
 
 const handleClick = (event: MouseEvent) => {
 	if (event.button === 0) {
-		const storedClickedEggs = localStorage.getItem("easter2025ClickedEggs");
-		const clickedEggs = storedClickedEggs ? JSON.parse(storedClickedEggs) : [];
+		const clickedEggs = readClickedEggs();
 
 		if (!clickedEggs.includes(id)) {
 			clickedEggs.push(id);
@@ -92,8 +98,7 @@ const copyCode = (source: string) => {
 const onLeavePopup = () => {
 	showPopup = false;
 
-	const storedClickedEggs = localStorage.getItem("easter2025ClickedEggs");
-	const clickedEggs = storedClickedEggs ? JSON.parse(storedClickedEggs) : [];
+	const clickedEggs = readClickedEggs();
 
 	clickedEggs.push(-1);
 	localStorage.setItem("easter2025ClickedEggs", JSON.stringify(clickedEggs));
diff --git a/src/lib/Tools/DumpProfile.svelte b/src/lib/Tools/DumpProfile.svelte
index a876f587..88605ffc 100644
--- a/src/lib/Tools/DumpProfile.svelte
+++ b/src/lib/Tools/DumpProfile.svelte
@@ -2,6 +2,7 @@
 import Spacer from "$lib/Layout/Spacer.svelte";
 import { dumpUser } from "$lib/Data/AniList/user";
 import RateLimited from "$lib/Error/RateLimited.svelte";
+import { parseJsonStringOrDefault } from "$lib/Effect/json";
 import Skeleton from "$lib/Loading/Skeleton.svelte";
 import InputTemplate from "./InputTemplate.svelte";
 import LZString from "lz-string";
@@ -9,19 +10,23 @@ import LZString from "lz-string";
 let submission = "";
 
 // Credit: @hoh
-const decodeJSON = (about: string): JSON | null => {
+const decodeJSON = (about: string): unknown | null => {
 	const match = (about || "").match(/^\[\]\(json([A-Za-z0-9+/=]+)\)/);
 
-	if (match)
-		try {
-			return JSON.parse(atob(match[1]));
-		} catch {
-			try {
-				return JSON.parse(LZString.decompressFromBase64(match[1]));
-			} catch {
-				return null;
-			}
-		}
+	if (match) {
+		const directDecoded = parseJsonStringOrDefault<unknown | null>(
+			atob(match[1]),
+			null,
+		);
+
+		if (directDecoded !== null) return directDecoded;
+
+		const decompressed = LZString.decompressFromBase64(match[1]);
+
+		if (!decompressed) return null;
+
+		return parseJsonStringOrDefault<unknown | null>(decompressed, null);
+	}
 
 	return null;
 };