3 files changed, 113 insertions, 0 deletions
diff --git a/apps/web/src/lib/fps/__tests__/fps.test.ts b/apps/web/src/lib/fps/__tests__/fps.test.ts
new file mode 100644
index 00000000..fd082bb2
--- /dev/null
+++ b/apps/web/src/lib/fps/__tests__/fps.test.ts
@@ -0,0 +1,65 @@
+import { describe, expect, test } from "bun:test";
+import {
+	getHighestImportedVideoFps,
+	getRaisedProjectFpsForImportedMedia,
+} from "@/lib/fps/utils";
+
+describe("getHighestImportedVideoFps", () => {
+	test("returns the highest valid video fps", () => {
+		expect(
+			getHighestImportedVideoFps({
+				mediaAssets: [
+					{ type: "audio" },
+					{ type: "video", fps: 30 },
+					{ type: "image", fps: 120 },
+					{ type: "video", fps: 60 },
+				],
+			}),
+		).toBe(60);
+	});
+
+	test("ignores missing and invalid fps values", () => {
+		expect(
+			getHighestImportedVideoFps({
+				mediaAssets: [
+					{ type: "video" },
+					{ type: "video", fps: 0 },
+					{ type: "video", fps: -10 },
+					{ type: "audio", fps: 120 },
+				],
+			}),
+		).toBeNull();
+	});
+});
+
+describe("getRaisedProjectFpsForImportedMedia", () => {
+	test("raises the project fps to match a higher-fps import", () => {
+		expect(
+			getRaisedProjectFpsForImportedMedia({
+				currentFps: 30,
+				importedAssets: [{ type: "video", fps: 60 }],
+			}),
+		).toBe(60);
+	});
+
+	test("does not lower the project fps for lower-fps imports", () => {
+		expect(
+			getRaisedProjectFpsForImportedMedia({
+				currentFps: 60,
+				importedAssets: [{ type: "video", fps: 10 }],
+			}),
+		).toBeNull();
+	});
+
+	test("ignores non-video imports", () => {
+		expect(
+			getRaisedProjectFpsForImportedMedia({
+				currentFps: 30,
+				importedAssets: [
+					{ type: "image", fps: 60 },
+					{ type: "audio", fps: 120 },
+				],
+			}),
+		).toBeNull();
+	});
+});
diff --git a/apps/web/src/lib/fps/constants.ts b/apps/web/src/lib/fps/constants.ts
new file mode 100644
index 00000000..100c043a
--- /dev/null
+++ b/apps/web/src/lib/fps/constants.ts
@@ -0,0 +1,9 @@
+export const FPS_PRESETS = [
+	{ value: "24", label: "24 fps" },
+	{ value: "25", label: "25 fps" },
+	{ value: "30", label: "30 fps" },
+	{ value: "60", label: "60 fps" },
+	{ value: "120", label: "120 fps" },
+] as const;
+
+export const DEFAULT_FPS = 30;
diff --git a/apps/web/src/lib/fps/utils.ts b/apps/web/src/lib/fps/utils.ts
new file mode 100644
index 00000000..8e3221a1
--- /dev/null
+++ b/apps/web/src/lib/fps/utils.ts
@@ -0,0 +1,39 @@
+import type { MediaAsset } from "@/lib/media/types";
+
+type MediaAssetFpsInput = Pick<MediaAsset, "type" | "fps">;
+
+export function getHighestImportedVideoFps({
+	mediaAssets,
+}: {
+	mediaAssets: MediaAssetFpsInput[];
+}): number | null {
+	let highestFps: number | null = null;
+
+	for (const asset of mediaAssets) {
+		const fps = asset.fps ?? Number.NaN;
+		if (asset.type !== "video") continue;
+		if (!Number.isFinite(fps) || fps <= 0) continue;
+
+		highestFps = highestFps === null ? fps : Math.max(highestFps, fps);
+	}
+
+	return highestFps;
+}
+
+export function getRaisedProjectFpsForImportedMedia({
+	currentFps,
+	importedAssets,
+}: {
+	currentFps: number;
+	importedAssets: MediaAssetFpsInput[];
+}): number | null {
+	const highestImportedVideoFps = getHighestImportedVideoFps({
+		mediaAssets: importedAssets,
+	});
+
+	if (highestImportedVideoFps === null || highestImportedVideoFps <= currentFps) {
+		return null;
+	}
+
+	return highestImportedVideoFps;
+}