Handle hair dye that is applied to hair only - add HairDyeMode and associated tests.

src/app/api/submit/route.ts

@@ -16,7 +16,7 @@ import { RateLimit } from "@/lib/rate-limit";
 import { validateImage } from "@/lib/images";
 import { convertQrCode } from "@/lib/qr-codes";
 import Mii from "@/lib/mii.js/mii";
-import TomodachiLifeMii from "@/lib/tomodachi-life-mii";
+import { TomodachiLifeMii } from "@/lib/tomodachi-life-mii";
 
 const uploadsDirectory = path.join(process.cwd(), "uploads");
 

src/components/submit-form/index.tsx

@@ -11,7 +11,7 @@ import qrcode from "qrcode-generator";
 import { nameSchema, tagsSchema } from "@/lib/schemas";
 import { convertQrCode } from "@/lib/qr-codes";
 import Mii from "@/lib/mii.js/mii";
-import TomodachiLifeMii from "@/lib/tomodachi-life-mii";
+import { TomodachiLifeMii } from "@/lib/tomodachi-life-mii";
 
 import TagSelector from "../tag-selector";
 import ImageList from "./image-list";

src/lib/qr-codes.test.ts

@@ -1,7 +1,7 @@
 import { convertQrCode } from "./qr-codes";
 import { describe, it, expect } from "vitest";
 import Mii from "./mii.js/mii";
-import TomodachiLifeMii from "./tomodachi-life-mii";
+import { TomodachiLifeMii, HairDyeMode } from "./tomodachi-life-mii";
 
 // List of encrypted QR code data to test against.
 const validQrCodes = [
@@ -26,12 +26,25 @@ const validQrCodes = [
 	},
 ];
 
+// 372 bytes of zeroes.
 const zeroes372 = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
 
+// 32 bytes of zeroes (too short to be a Mii QR code).
 const length32 = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=";
 
+// Mii QR code encrypted correctly but has an invalid CRC-16 checksum.
 const badCrc = "ULENrXILeXZooDaJvwHMcFaBjGH7k5pj+DDPDV0irq66c01Fh82TIrZerZX2xiB+TbHBzYIaDHdryA9IbR1uH/slSalGCScmjDiL9zpOXlvh8z38NGkmjtL1fVVrshCcJHKeQApdbZU4S6h+wZd0LA==";
 
+// Hair dye should be applied to hair only.
+const hairDyeHairOnly = "lHDnfRgqe2+drU303Slkj7+o4JldrKcIdOl5zgLM0LpwQKQY+i3cpt5IIg7LBNAr7TCzHOvi698oUV0QkcyNj71MgtAAaw4MvOdT4dsv0PLof6E7IcjgnCA1ZAJ2Bs5PQTnM/yuVBUIXdq6WYh+nmG3HtxV7zKbEpSy4bqVep8uuvUlfZcB+BQgucPXQLmDnS8ECKwOlANcKTI+ZjIZggVaEsyY88pjRWyXnwe1z4Favw16bIzecesehGlqXzZh9U5Vm5dZP8wmKc3G6TGylYmbnloRd99UYRNULvTQCUer8WljGuV30ftXlJOwfsnwoAiVOGoG3KvbsBpPtPLywR5DavRgQIPd0/b+XUzHQDhkyftMXeqVEalsuEmU/b/1/j4yVL+2lWgD1i2xyET65uJawAnd8jbKbG8lxPMgzIKGVqJB4QmJOl9/dTf21r9GgRFRaFEz+66bVfiYhzXKmJUQv2qx/t/V3r96QzYd08nrWSHK0";
+const hairDyeHairOnlyExpectedCommonColor = 99; // Must apply to hair but not eyebrow and beard.
+// Hair dye should be applied to hair, eyebrow, and beard.
+const hairDyeHairEyebrowBeard = validQrCodes[1].base64; // Miku has hair dye.
+const hairDyeHairEyebrowBeardExpectedCommonColor = 67; // Must apply to hair, eyebrow, and beard.
+
+// Should not have hair dye enabled.
+const hairDyeMode0 = validQrCodes[0].base64; // Frieren doesn't have hair dye
+
 function base64ToUint8Array(base64: string): Uint8Array {
 	const binary = Buffer.from(base64, "base64");
 	return new Uint8Array(binary.buffer, binary.byteOffset, binary.byteLength);
@@ -71,12 +84,43 @@ describe("convertQrCode", () => {
 		// Verified by new Mii() constructor from mii-js.
 		expect(() => convertQrCode(bytes)).toThrow("Mii data is not valid");
 	});
-	/*
-  it('should censor bad words in names', () => {
-    const qrWithSwears = // TODO TODO
-    const { tomodachiLifeMii } = convertQrCode(qrWithSwears);
 
-    expect(tomodachiLifeMii.firstName).not.toMatch(/INSERT_SWEARS_HERE/i);
-  });
+	it("should apply hair dye to hair, eyebrow, and beard", () => {
+		const bytes = base64ToUint8Array(hairDyeHairEyebrowBeard);
+		const { mii, tomodachiLifeMii } = convertQrCode(bytes);
+
+		expect(tomodachiLifeMii.hairDyeMode).toBe(HairDyeMode.HairEyebrowBeard);
+		expect(tomodachiLifeMii.studioHairColor).toBe(hairDyeHairEyebrowBeardExpectedCommonColor);
+		expect(mii.hairColor).toBe(hairDyeHairEyebrowBeardExpectedCommonColor);
+		expect(mii.eyebrowColor).toBe(hairDyeHairEyebrowBeardExpectedCommonColor);
+		expect(mii.facialHairColor).toBe(hairDyeHairEyebrowBeardExpectedCommonColor);
+	});
+
+	it("should apply hair dye to hair only", () => {
+		const bytes = base64ToUint8Array(hairDyeHairOnly);
+		const { mii, tomodachiLifeMii } = convertQrCode(bytes);
+
+		expect(tomodachiLifeMii.hairDyeMode).toBe(HairDyeMode.Hair);
+		expect(tomodachiLifeMii.studioHairColor).toBe(hairDyeHairOnlyExpectedCommonColor);
+		expect(mii.hairColor).toBe(hairDyeHairOnlyExpectedCommonColor);
+		expect(mii.eyebrowColor === hairDyeHairOnlyExpectedCommonColor).toBe(false);
+		expect(mii.facialHairColor === hairDyeHairOnlyExpectedCommonColor).toBe(false);
+	});
+
+	it("should not apply hair dye if mode is 0", () => {
+		const bytes = base64ToUint8Array(hairDyeMode0);
+		const { mii, tomodachiLifeMii } = convertQrCode(bytes);
+
+		expect(tomodachiLifeMii.hairDyeMode).toBe(HairDyeMode.None);
+		expect(mii.hairColor === tomodachiLifeMii.studioHairColor).toBe(false);
+		expect(mii.hairColor === mii.facialHairColor).toBe(false);
+	});
+
+	/*
+	it('should censor bad words in names', () => {
+		const qrWithSwears = // TODO TODO
+		const { tomodachiLifeMii } = convertQrCode(qrWithSwears);
+		expect(tomodachiLifeMii.firstName).not.toMatch(/INSERT_SWEARS_HERE/i);
+	});
   */
 });

src/lib/qr-codes.ts

@@ -4,7 +4,7 @@ import sjcl from "sjcl-with-all";
 
 import { MII_DECRYPTION_KEY, MII_QR_ENCRYPTED_LENGTH } from "./constants";
 import Mii from "./mii.js/mii";
-import TomodachiLifeMii from "./tomodachi-life-mii";
+import { TomodachiLifeMii, HairDyeMode } from "./tomodachi-life-mii";
 
 // AES-CCM encrypted Mii QR codes have some errata (https://www.3dbrew.org/wiki/AES_Registers#CCM_mode_pitfall)
 // causing them to not be easily decryptable by asmcrypto
@@ -89,10 +89,15 @@ export function convertQrCode(bytes: Uint8Array): { mii: Mii; tomodachiLifeMii:
 		const tomodachiLifeMii = TomodachiLifeMii.fromBytes(bytes);
 
 		// Apply hair dye fields.
-		if (tomodachiLifeMii.hairDyeEnabled) {
-			mii.hairColor = tomodachiLifeMii.studioHairColor;
-			mii.eyebrowColor = tomodachiLifeMii.studioHairColor;
-			mii.facialHairColor = tomodachiLifeMii.studioHairColor;
+		switch (tomodachiLifeMii.hairDyeMode) {
+			case HairDyeMode.HairEyebrowBeard:
+				mii.eyebrowColor = tomodachiLifeMii.studioHairColor;
+				mii.facialHairColor = tomodachiLifeMii.studioHairColor;
+				// Fall-through and also apply to hair.
+			case HairDyeMode.Hair:
+				mii.hairColor = tomodachiLifeMii.studioHairColor;
+				break;
+			// Default: do not apply hair dye.
 		}
 
 		// Censor potential inappropriate words.

src/lib/tomodachi-life-mii.ts

@@ -11,15 +11,23 @@ const hairDyeConverter = [
 	55, 51, 50, 12, 16, 12, 67, 61, 51, 64, 69, 66, 65, 86, 85, 93, 92, 19, 20, 20, 15, 32, 35, 26, 38, 41, 43, 18, 95, 97, 97, 99,
 ];
 
+// All possible values for 2-bit hair dye mode.
+export enum HairDyeMode {
+	None = 0,
+	Hair = 1,
+	HairEyebrowBeard = 2,
+	Invalid = 3,
+}
+
 // Reference: https://github.com/ariankordi/nwf-mii-cemu-toy/blob/ffl-renderer-proto-integrate/assets/kaitai-structs/tomodachi_life_qr_code.ksy
 // (Credits to ariankordi for the byte locations)
-export default class TomodachiLifeMii {
+export class TomodachiLifeMii {
 	firstName: string;
 	lastName: string;
 	islandName: string;
 
 	hairDye: number;
-	hairDyeEnabled: boolean;
+	hairDyeMode: HairDyeMode;
 
 	// There are more properties but I don't plan to add them *yet*
 
@@ -38,10 +46,10 @@ export default class TomodachiLifeMii {
 		// Skip 3 unknown bytes
 		offset += 3;
 
-		// Read bit fields
+		// Read little-endian bit fields
 		const bitField = view.getUint8(offset++);
-		this.hairDyeEnabled = (bitField & 0x80) !== 0;
-		this.hairDye = (bitField & 0x3e) >> 1;
+		this.hairDyeMode = (bitField >> 6) & 0b00000011; // Bits 7-6
+		this.hairDye = (bitField >> 1) & 0b00011111; // Bits 5-1
 
 		// Skip 12 unknown bytes
 		offset += 12;