2 files changed, 49 insertions, 1 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,
+	});
+};