fix: copy mii.js and edit it

package.json

@@ -11,10 +11,10 @@
 	},
 	"dependencies": {
 		"@auth/prisma-adapter": "2.7.2",
-		"@pretendonetwork/mii-js": "github:PretendoNetwork/mii-js#publish-and-eslint",
 		"@prisma/client": "^6.5.0",
 		"@trafficlunar/asmcrypto.js": "^1.0.2",
 		"@yudiel/react-qr-scanner": "2.2.2-beta.2",
+		"bit-buffer": "^0.2.5",
 		"embla-carousel-react": "^8.5.2",
 		"jsqr": "^1.4.0",
 		"next": "15.2.4",

pnpm-lock.yaml

@@ -11,9 +11,6 @@ importers:
       '@auth/prisma-adapter':
         specifier: 2.7.2
         version: 2.7.2(@prisma/client@6.5.0(prisma@6.5.0(typescript@5.8.2))(typescript@5.8.2))
-      '@pretendonetwork/mii-js':
-        specifier: github:PretendoNetwork/mii-js#publish-and-eslint
-        version: https://codeload.github.com/PretendoNetwork/mii-js/tar.gz/8b857460b61dde9729eff848d99fd3ef9128f2a5
       '@prisma/client':
         specifier: ^6.5.0
         version: 6.5.0(prisma@6.5.0(typescript@5.8.2))(typescript@5.8.2)
@@ -23,6 +20,9 @@ importers:
       '@yudiel/react-qr-scanner':
         specifier: 2.2.2-beta.2
         version: 2.2.2-beta.2(@types/emscripten@1.40.1)(react-dom@19.1.0(react@19.1.0))(react@19.1.0)
+      bit-buffer:
+        specifier: ^0.2.5
+        version: 0.2.5
       embla-carousel-react:
         specifier: ^8.5.2
         version: 8.5.2(react@19.1.0)
@@ -745,10 +745,6 @@ packages:
   '@panva/hkdf@1.2.1':
     resolution: {integrity: sha512-6oclG6Y3PiDFcoyk8srjLfVKyMfVCKJ27JwNPViuXziFpmdz+MZnZN/aKY0JGXgYuO/VghU0jcOAZgWXZ1Dmrw==}
 
-  '@pretendonetwork/mii-js@https://codeload.github.com/PretendoNetwork/mii-js/tar.gz/8b857460b61dde9729eff848d99fd3ef9128f2a5':
-    resolution: {tarball: https://codeload.github.com/PretendoNetwork/mii-js/tar.gz/8b857460b61dde9729eff848d99fd3ef9128f2a5}
-    version: 1.0.4
-
   '@prisma/client@6.5.0':
     resolution: {integrity: sha512-M6w1Ql/BeiGoZmhMdAZUXHu5sz5HubyVcKukbLs3l0ELcQb8hTUJxtGEChhv4SVJ0QJlwtLnwOLgIRQhpsm9dw==}
     engines: {node: '>=18.18'}
@@ -2933,10 +2929,6 @@ snapshots:
 
   '@panva/hkdf@1.2.1': {}
 
-  '@pretendonetwork/mii-js@https://codeload.github.com/PretendoNetwork/mii-js/tar.gz/8b857460b61dde9729eff848d99fd3ef9128f2a5':
-    dependencies:
-      bit-buffer: 0.2.5
-
   '@prisma/client@6.5.0(prisma@6.5.0(typescript@5.8.2))(typescript@5.8.2)':
     optionalDependencies:
       prisma: 6.5.0(typescript@5.8.2)

src/app/api/submit/route.ts

@@ -3,7 +3,6 @@ import path from "path";
 import sharp from "sharp";
 
 import { AES_CCM } from "@trafficlunar/asmcrypto.js";
-import Mii from "@pretendonetwork/mii-js";
 import qrcode from "qrcode-generator";
 
 import { auth } from "@/lib/auth";
@@ -11,6 +10,8 @@ import { prisma } from "@/lib/prisma";
 import { MII_DECRYPTION_KEY } from "@/lib/constants";
 import { nameSchema, tagsSchema } from "@/lib/schemas";
 
+import Mii from "@/utils/mii.js/mii";
+
 const uploadsDirectory = path.join(process.cwd(), "public", "uploads");
 
 export async function POST(request: Request) {
@@ -32,7 +33,8 @@ export async function POST(request: Request) {
 
 	const qrBytes = new Uint8Array(qrBytesRaw);
 
-	// Decrypt the QR code
+	// Decrypt the Mii part of the QR code
+	// (Credits to kazuki-4ys)
 	const nonce = qrBytes.subarray(0, 8);
 	const content = qrBytes.subarray(8, 0x70);
 

src/app/components/submit-form.tsx

@@ -7,12 +7,13 @@ import { useDropzone } from "react-dropzone";
 import { Icon } from "@iconify/react";
 
 import { AES_CCM } from "@trafficlunar/asmcrypto.js";
-import Mii from "@pretendonetwork/mii-js";
 import qrcode from "qrcode-generator";
 
 import { MII_DECRYPTION_KEY } from "@/lib/constants";
 import { nameSchema, tagsSchema } from "@/lib/schemas";
 
+import Mii from "@/utils/mii.js/mii";
+
 import TagSelector from "./submit/tag-selector";
 import QrUpload from "./submit/qr-upload";
 import QrScanner from "./submit/qr-scanner";

src/utils/mii.js/README.md

@@ -0,0 +1,3 @@
+Every file in here is from https://github.com/PretendoNetwork/mii-js/
+
+./mii.ts has been edited to remove the asset URL functions and remove some assertions related to hair dye (hairColor, facialHairColor, eyebrowColor)

src/utils/mii.js/extended-bit-stream.ts

@@ -0,0 +1,88 @@
+// Stolen from https://github.com/PretendoNetwork/mii-js/
+
+import { BitStream } from "bit-buffer";
+
+export default class ExtendedBitStream extends BitStream {
+	constructor(buffer: Buffer) {
+		super(buffer, buffer.byteOffset, buffer.byteLength);
+	}
+
+	public swapEndian(): void {
+		this.bigEndian = !this.bigEndian;
+	}
+
+	// the type definition for BitStream does not include the _index property
+	// since it's supposed to be private, but it's needed 4 times here sooo
+
+	public alignByte(): void {
+		// @ts-expect-error _index is private
+		const nextClosestByteIndex = 8 * Math.ceil(this._index / 8);
+		// @ts-expect-error _index is private
+		const bitDistance = nextClosestByteIndex - this._index;
+
+		this.skipBits(bitDistance);
+	}
+
+	public bitSeek(bitPos: number): void {
+		// @ts-expect-error _index is private
+		this._index = bitPos;
+	}
+
+	public skipBits(bitCount: number): void {
+		// @ts-expect-error _index is private
+		this._index += bitCount;
+	}
+
+	public skipBytes(bytes: number): void {
+		const bits = bytes * 8;
+		this.skipBits(bits);
+	}
+
+	public skipBit(): void {
+		this.skipBits(1);
+	}
+
+	public skipInt8(): void {
+		this.skipBytes(1);
+	}
+
+	public skipInt16(): void {
+		// Skipping a uint16 is the same as skipping 2 uint8's
+		this.skipBytes(2);
+	}
+
+	public readBit(): number {
+		return this.readBits(1);
+	}
+
+	public readBytes(length: number): number[] {
+		return Array(length)
+			.fill(0)
+			.map(() => this.readUint8());
+	}
+
+	public readBuffer(length: number): Buffer {
+		return Buffer.from(this.readBytes(length));
+	}
+
+	public readUTF16String(length: number): string {
+		return this.readBuffer(length).toString("utf16le").replace(/\0.*$/, "");
+	}
+
+	public writeBit(bit: number): void {
+		this.writeBits(bit, 1);
+	}
+
+	public writeBuffer(buffer: Buffer): void {
+		buffer.forEach((byte) => this.writeUint8(byte));
+	}
+
+	public writeUTF16String(string: string): void {
+		const stringBuffer = Buffer.from(string, "utf16le");
+		const terminatedBuffer = Buffer.alloc(0x14);
+
+		stringBuffer.copy(terminatedBuffer);
+
+		this.writeBuffer(terminatedBuffer);
+	}
+}

src/utils/mii.js/mii.ts

@@ -0,0 +1,553 @@
+// Stolen and edited from https://github.com/PretendoNetwork/mii-js/
+
+import assert from "assert";
+import ExtendedBitStream from "./extended-bit-stream";
+import Util from "./util";
+
+const STUDIO_RENDER_URL_BASE = "https://studio.mii.nintendo.com/miis/image.png";
+
+const STUDIO_RENDER_DEFAULTS = {
+	type: "face",
+	expression: "normal",
+	width: 96,
+	bgColor: "FFFFFF00",
+	clothesColor: "default",
+	cameraXRotate: 0,
+	cameraYRotate: 0,
+	cameraZRotate: 0,
+	characterXRotate: 0,
+	characterYRotate: 0,
+	characterZRotate: 0,
+	lightXDirection: 0,
+	lightYDirection: 0,
+	lightZDirection: 0,
+	lightDirectionMode: "none",
+	instanceCount: 1,
+	instanceRotationMode: "model",
+};
+
+const STUDIO_RENDER_TYPES = ["face", "face_only", "all_body"];
+
+const STUDIO_RENDER_EXPRESSIONS = [
+	"normal",
+	"smile",
+	"anger",
+	"sorrow",
+	"surprise",
+	"blink",
+	"normal_open_mouth",
+	"smile_open_mouth",
+	"anger_open_mouth",
+	"surprise_open_mouth",
+	"sorrow_open_mouth",
+	"blink_open_mouth",
+	"wink_left",
+	"wink_right",
+	"wink_left_open_mouth",
+	"wink_right_open_mouth",
+	"like_wink_left",
+	"like_wink_right",
+	"frustrated",
+];
+
+const STUDIO_RENDER_CLOTHES_COLORS = [
+	"default",
+	"red",
+	"orange",
+	"yellow",
+	"yellowgreen",
+	"green",
+	"blue",
+	"skyblue",
+	"pink",
+	"purple",
+	"brown",
+	"white",
+	"black",
+];
+
+const STUDIO_RENDER_LIGHT_DIRECTION_MODS = ["none", "zerox", "flipx", "camera", "offset", "set"];
+
+const STUDIO_RENDER_INSTANCE_ROTATION_MODES = ["model", "camera", "both"];
+
+const STUDIO_BG_COLOR_REGEX = /^[0-9A-F]{8}$/; // Mii Studio does not allow lowercase
+
+export default class Mii {
+	public bitStream: ExtendedBitStream;
+
+	// Mii data
+	// can be sure that these are all initialized in decode()
+
+	public version!: number;
+	public allowCopying!: boolean;
+	public profanityFlag!: boolean;
+	public regionLock!: number;
+	public characterSet!: number;
+	public pageIndex!: number;
+	public slotIndex!: number;
+	public unknown1!: number;
+	public deviceOrigin!: number;
+	public systemId!: Buffer;
+	public normalMii!: boolean;
+	public dsMii!: boolean;
+	public nonUserMii!: boolean;
+	public isValid!: boolean;
+	public creationTime!: number;
+	public consoleMAC!: Buffer;
+	public gender!: number;
+	public birthMonth!: number;
+	public birthDay!: number;
+	public favoriteColor!: number;
+	public favorite!: boolean;
+	public miiName!: string;
+	public height!: number;
+	public build!: number;
+	public disableSharing!: boolean;
+	public faceType!: number;
+	public skinColor!: number;
+	public wrinklesType!: number;
+	public makeupType!: number;
+	public hairType!: number;
+	public hairColor!: number;
+	public flipHair!: boolean;
+	public eyeType!: number;
+	public eyeColor!: number;
+	public eyeScale!: number;
+	public eyeVerticalStretch!: number;
+	public eyeRotation!: number;
+	public eyeSpacing!: number;
+	public eyeYPosition!: number;
+	public eyebrowType!: number;
+	public eyebrowColor!: number;
+	public eyebrowScale!: number;
+	public eyebrowVerticalStretch!: number;
+	public eyebrowRotation!: number;
+	public eyebrowSpacing!: number;
+	public eyebrowYPosition!: number;
+	public noseType!: number;
+	public noseScale!: number;
+	public noseYPosition!: number;
+	public mouthType!: number;
+	public mouthColor!: number;
+	public mouthScale!: number;
+	public mouthHorizontalStretch!: number;
+	public mouthYPosition!: number;
+	public mustacheType!: number;
+	public unknown2!: number;
+	public beardType!: number;
+	public facialHairColor!: number;
+	public mustacheScale!: number;
+	public mustacheYPosition!: number;
+	public glassesType!: number;
+	public glassesColor!: number;
+	public glassesScale!: number;
+	public glassesYPosition!: number;
+	public moleEnabled!: boolean;
+	public moleScale!: number;
+	public moleXPosition!: number;
+	public moleYPosition!: number;
+	public creatorName!: string;
+	public checksum!: number;
+
+	constructor(buffer: Buffer) {
+		this.bitStream = new ExtendedBitStream(buffer);
+		this.decode();
+	}
+
+	public validate(): void {
+		// Size check
+		assert.equal(this.bitStream.length / 8, 0x60, `Invalid Mii data size. Got ${this.bitStream.length / 8}, expected 96`);
+
+		// Value range and type checks
+		assert.ok(this.version === 0 || this.version === 3, `Invalid Mii version. Got ${this.version}, expected 0 or 3`);
+		assert.equal(typeof this.allowCopying, "boolean", `Invalid Mii allow copying. Got ${this.allowCopying}, expected true or false`);
+		assert.equal(typeof this.profanityFlag, "boolean", `Invalid Mii profanity flag. Got ${this.profanityFlag}, expected true or false`);
+		assert.ok(Util.inRange(this.regionLock, Util.range(4)), `Invalid Mii region lock. Got ${this.regionLock}, expected 0-3`);
+		assert.ok(Util.inRange(this.characterSet, Util.range(4)), `Invalid Mii region lock. Got ${this.characterSet}, expected 0-3`);
+		assert.ok(Util.inRange(this.pageIndex, Util.range(10)), `Invalid Mii page index. Got ${this.pageIndex}, expected 0-9`);
+		assert.ok(Util.inRange(this.slotIndex, Util.range(10)), `Invalid Mii slot index. Got ${this.slotIndex}, expected 0-9`);
+		assert.equal(this.unknown1, 0, `Invalid Mii unknown1. Got ${this.unknown1}, expected 0`);
+		assert.ok(Util.inRange(this.deviceOrigin, Util.range(1, 5)), `Invalid Mii device origin. Got ${this.deviceOrigin}, expected 1-4`);
+		assert.equal(this.systemId.length, 8, `Invalid Mii system ID size. Got ${this.systemId.length}, system IDs must be 8 bytes long`);
+		assert.equal(typeof this.normalMii, "boolean", `Invalid normal Mii flag. Got ${this.normalMii}, expected true or false`);
+		assert.equal(typeof this.dsMii, "boolean", `Invalid DS Mii flag. Got ${this.dsMii}, expected true or false`);
+		assert.equal(typeof this.nonUserMii, "boolean", `Invalid non-user Mii flag. Got ${this.nonUserMii}, expected true or false`);
+		assert.equal(typeof this.isValid, "boolean", `Invalid Mii valid flag. Got ${this.isValid}, expected true or false`);
+		assert.ok(this.creationTime < 268435456, `Invalid Mii creation time. Got ${this.creationTime}, max value for 28 bit integer is 268,435,456`);
+		assert.equal(
+			this.consoleMAC.length,
+			6,
+			`Invalid Mii console MAC address size. Got ${this.consoleMAC.length}, console MAC addresses must be 6 bytes long`
+		);
+		assert.ok(Util.inRange(this.gender, Util.range(2)), `Invalid Mii gender. Got ${this.gender}, expected 0 or 1`);
+		assert.ok(Util.inRange(this.birthMonth, Util.range(13)), `Invalid Mii birth month. Got ${this.birthMonth}, expected 0-12`);
+		assert.ok(Util.inRange(this.birthDay, Util.range(32)), `Invalid Mii birth day. Got ${this.birthDay}, expected 0-31`);
+		assert.ok(Util.inRange(this.favoriteColor, Util.range(12)), `Invalid Mii favorite color. Got ${this.favoriteColor}, expected 0-11`);
+		assert.equal(typeof this.favorite, "boolean", `Invalid favorite Mii flag. Got ${this.favorite}, expected true or false`);
+		assert.ok(Buffer.from(this.miiName, "utf16le").length <= 0x14, `Invalid Mii name. Got ${this.miiName}, name may only be up to 10 characters`);
+		assert.ok(Util.inRange(this.height, Util.range(128)), `Invalid Mii height. Got ${this.height}, expected 0-127`);
+		assert.ok(Util.inRange(this.build, Util.range(128)), `Invalid Mii build. Got ${this.build}, expected 0-127`);
+		assert.equal(typeof this.disableSharing, "boolean", `Invalid disable sharing Mii flag. Got ${this.disableSharing}, expected true or false`);
+		assert.ok(Util.inRange(this.faceType, Util.range(12)), `Invalid Mii face type. Got ${this.faceType}, expected 0-11`);
+		assert.ok(Util.inRange(this.skinColor, Util.range(7)), `Invalid Mii skin color. Got ${this.skinColor}, expected 0-6`);
+		assert.ok(Util.inRange(this.wrinklesType, Util.range(12)), `Invalid Mii wrinkles type. Got ${this.wrinklesType}, expected 0-11`);
+		assert.ok(Util.inRange(this.makeupType, Util.range(12)), `Invalid Mii makeup type. Got ${this.makeupType}, expected 0-11`);
+		assert.ok(Util.inRange(this.hairType, Util.range(132)), `Invalid Mii hair type. Got ${this.hairType}, expected 0-131`);
+		// assert.ok(Util.inRange(this.hairColor, Util.range(8)), `Invalid Mii hair color. Got ${this.hairColor}, expected 0-7`);
+		assert.equal(typeof this.flipHair, "boolean", `Invalid flip hair flag. Got ${this.flipHair}, expected true or false`);
+		assert.ok(Util.inRange(this.eyeType, Util.range(60)), `Invalid Mii eye type. Got ${this.eyeType}, expected 0-59`);
+		assert.ok(Util.inRange(this.eyeColor, Util.range(6)), `Invalid Mii eye color. Got ${this.eyeColor}, expected 0-5`);
+		assert.ok(Util.inRange(this.eyeScale, Util.range(8)), `Invalid Mii eye scale. Got ${this.eyeScale}, expected 0-7`);
+		assert.ok(Util.inRange(this.eyeVerticalStretch, Util.range(7)), `Invalid Mii eye vertical stretch. Got ${this.eyeVerticalStretch}, expected 0-6`);
+		assert.ok(Util.inRange(this.eyeRotation, Util.range(8)), `Invalid Mii eye rotation. Got ${this.eyeRotation}, expected 0-7`);
+		assert.ok(Util.inRange(this.eyeSpacing, Util.range(13)), `Invalid Mii eye spacing. Got ${this.eyeSpacing}, expected 0-12`);
+		assert.ok(Util.inRange(this.eyeYPosition, Util.range(19)), `Invalid Mii eye Y position. Got ${this.eyeYPosition}, expected 0-18`);
+		assert.ok(Util.inRange(this.eyebrowType, Util.range(25)), `Invalid Mii eyebrow type. Got ${this.eyebrowType}, expected 0-24`);
+		// assert.ok(Util.inRange(this.eyebrowColor, Util.range(8)), `Invalid Mii eyebrow color. Got ${this.eyebrowColor}, expected 0-7`);
+		assert.ok(Util.inRange(this.eyebrowScale, Util.range(9)), `Invalid Mii eyebrow scale. Got ${this.eyebrowScale}, expected 0-8`);
+		assert.ok(
+			Util.inRange(this.eyebrowVerticalStretch, Util.range(7)),
+			`Invalid Mii eyebrow vertical stretch. Got ${this.eyebrowVerticalStretch}, expected 0-6`
+		);
+		assert.ok(Util.inRange(this.eyebrowRotation, Util.range(12)), `Invalid Mii eyebrow rotation. Got ${this.eyebrowRotation}, expected 0-11`);
+		assert.ok(Util.inRange(this.eyebrowSpacing, Util.range(13)), `Invalid Mii eyebrow spacing. Got ${this.eyebrowSpacing}, expected 0-12`);
+		assert.ok(Util.inRange(this.eyebrowYPosition, Util.range(3, 19)), `Invalid Mii eyebrow Y position. Got ${this.eyebrowYPosition}, expected 3-18`);
+		assert.ok(Util.inRange(this.noseType, Util.range(18)), `Invalid Mii nose type. Got ${this.noseType}, expected 0-17`);
+		assert.ok(Util.inRange(this.noseScale, Util.range(9)), `Invalid Mii nose scale. Got ${this.noseScale}, expected 0-8`);
+		assert.ok(Util.inRange(this.noseYPosition, Util.range(19)), `Invalid Mii nose Y position. Got ${this.noseYPosition}, expected 0-18`);
+		assert.ok(Util.inRange(this.mouthType, Util.range(36)), `Invalid Mii mouth type. Got ${this.mouthType}, expected 0-35`);
+		assert.ok(Util.inRange(this.mouthColor, Util.range(5)), `Invalid Mii mouth color. Got ${this.mouthColor}, expected 0-4`);
+		assert.ok(Util.inRange(this.mouthScale, Util.range(9)), `Invalid Mii mouth scale. Got ${this.mouthScale}, expected 0-8`);
+		assert.ok(
+			Util.inRange(this.mouthHorizontalStretch, Util.range(7)),
+			`Invalid Mii mouth stretch. Got ${this.mouthHorizontalStretch}, expected 0-6`
+		);
+		assert.ok(Util.inRange(this.mouthYPosition, Util.range(19)), `Invalid Mii mouth Y position. Got ${this.mouthYPosition}, expected 0-18`);
+		assert.ok(Util.inRange(this.mustacheType, Util.range(6)), `Invalid Mii mustache type. Got ${this.mustacheType}, expected 0-5`);
+		assert.ok(Util.inRange(this.beardType, Util.range(6)), `Invalid Mii beard type. Got ${this.beardType}, expected 0-5`);
+		// assert.ok(Util.inRange(this.facialHairColor, Util.range(8)), `Invalid Mii beard type. Got ${this.facialHairColor}, expected 0-7`);
+		assert.ok(Util.inRange(this.mustacheScale, Util.range(9)), `Invalid Mii mustache scale. Got ${this.mustacheScale}, expected 0-8`);
+		assert.ok(Util.inRange(this.mustacheYPosition, Util.range(17)), `Invalid Mii mustache Y position. Got ${this.mustacheYPosition}, expected 0-16`);
+		assert.ok(Util.inRange(this.glassesType, Util.range(9)), `Invalid Mii glassess type. Got ${this.glassesType}, expected 0-8`);
+		assert.ok(Util.inRange(this.glassesColor, Util.range(6)), `Invalid Mii glassess type. Got ${this.glassesColor}, expected 0-5`);
+		assert.ok(Util.inRange(this.glassesScale, Util.range(8)), `Invalid Mii glassess type. Got ${this.glassesScale}, expected 0-7`);
+		assert.ok(Util.inRange(this.glassesYPosition, Util.range(21)), `Invalid Mii glassess Y position. Got ${this.glassesYPosition}, expected 0-20`);
+		assert.equal(typeof this.moleEnabled, "boolean", `Invalid mole enabled flag. Got ${this.moleEnabled}, expected true or false`);
+		assert.ok(Util.inRange(this.moleScale, Util.range(9)), `Invalid Mii mole scale. Got ${this.moleScale}, expected 0-8`);
+		assert.ok(Util.inRange(this.moleXPosition, Util.range(17)), `Invalid Mii mole X position. Got ${this.moleXPosition}, expected 0-16`);
+		assert.ok(Util.inRange(this.moleYPosition, Util.range(31)), `Invalid Mii mole Y position. Got ${this.moleYPosition}, expected 0-30`);
+
+		// Sanity checks
+		/*
+
+        HEYimHeroic says this check must be true,
+        but in my testing my Mii's have both these flags
+        set and are valid
+
+        Commenting out until we get more info
+
+        if (this.dsMii && this.isValid) {
+            assert.fail('If DS Mii flag is true, the is valid flag must be false');
+        }
+        */
+
+		if (this.nonUserMii && (this.creationTime !== 0 || this.isValid || this.dsMii || this.normalMii)) {
+			assert.fail("Non-user Mii's must have all other Mii ID bits set to 0");
+		}
+
+		if (!this.normalMii && !this.disableSharing) {
+			assert.fail("Special Miis must have sharing disabled");
+		}
+	}
+
+	public decode(): void {
+		this.version = this.bitStream.readUint8();
+		this.allowCopying = this.bitStream.readBoolean();
+		this.profanityFlag = this.bitStream.readBoolean();
+		this.regionLock = this.bitStream.readBits(2);
+		this.characterSet = this.bitStream.readBits(2);
+		this.bitStream.alignByte();
+		this.pageIndex = this.bitStream.readBits(4);
+		this.slotIndex = this.bitStream.readBits(4);
+		this.unknown1 = this.bitStream.readBits(4);
+		this.deviceOrigin = this.bitStream.readBits(3);
+		this.bitStream.alignByte();
+		this.systemId = this.bitStream.readBuffer(8);
+		this.bitStream.swapEndian(); // * Mii ID data is BE
+		this.normalMii = this.bitStream.readBoolean();
+		this.dsMii = this.bitStream.readBoolean();
+		this.nonUserMii = this.bitStream.readBoolean();
+		this.isValid = this.bitStream.readBoolean();
+		this.creationTime = this.bitStream.readBits(28);
+		this.bitStream.swapEndian(); // * Swap back to LE
+		this.consoleMAC = this.bitStream.readBuffer(6);
+		this.bitStream.skipInt16(); // * 0x0000 padding
+		this.gender = this.bitStream.readBit();
+		this.birthMonth = this.bitStream.readBits(4);
+		this.birthDay = this.bitStream.readBits(5);
+		this.favoriteColor = this.bitStream.readBits(4);
+		this.favorite = this.bitStream.readBoolean();
+		this.bitStream.alignByte();
+		this.miiName = this.bitStream.readUTF16String(0x14);
+		this.height = this.bitStream.readUint8();
+		this.build = this.bitStream.readUint8();
+		this.disableSharing = this.bitStream.readBoolean();
+		this.faceType = this.bitStream.readBits(4);
+		this.skinColor = this.bitStream.readBits(3);
+		this.wrinklesType = this.bitStream.readBits(4);
+		this.makeupType = this.bitStream.readBits(4);
+		this.hairType = this.bitStream.readUint8();
+		this.hairColor = this.bitStream.readBits(3);
+		this.flipHair = this.bitStream.readBoolean();
+		this.bitStream.alignByte();
+		this.eyeType = this.bitStream.readBits(6);
+		this.eyeColor = this.bitStream.readBits(3);
+		this.eyeScale = this.bitStream.readBits(4);
+		this.eyeVerticalStretch = this.bitStream.readBits(3);
+		this.eyeRotation = this.bitStream.readBits(5);
+		this.eyeSpacing = this.bitStream.readBits(4);
+		this.eyeYPosition = this.bitStream.readBits(5);
+		this.bitStream.alignByte();
+		this.eyebrowType = this.bitStream.readBits(5);
+		this.eyebrowColor = this.bitStream.readBits(3);
+		this.eyebrowScale = this.bitStream.readBits(4);
+		this.eyebrowVerticalStretch = this.bitStream.readBits(3);
+		this.bitStream.skipBit();
+		this.eyebrowRotation = this.bitStream.readBits(4);
+		this.bitStream.skipBit();
+		this.eyebrowSpacing = this.bitStream.readBits(4);
+		this.eyebrowYPosition = this.bitStream.readBits(5);
+		this.bitStream.alignByte();
+		this.noseType = this.bitStream.readBits(5);
+		this.noseScale = this.bitStream.readBits(4);
+		this.noseYPosition = this.bitStream.readBits(5);
+		this.bitStream.alignByte();
+		this.mouthType = this.bitStream.readBits(6);
+		this.mouthColor = this.bitStream.readBits(3);
+		this.mouthScale = this.bitStream.readBits(4);
+		this.mouthHorizontalStretch = this.bitStream.readBits(3);
+		this.mouthYPosition = this.bitStream.readBits(5);
+		this.mustacheType = this.bitStream.readBits(3);
+		this.unknown2 = this.bitStream.readUint8();
+		this.beardType = this.bitStream.readBits(3);
+		this.facialHairColor = this.bitStream.readBits(3);
+		this.mustacheScale = this.bitStream.readBits(4);
+		this.mustacheYPosition = this.bitStream.readBits(5);
+		this.bitStream.alignByte();
+		this.glassesType = this.bitStream.readBits(4);
+		this.glassesColor = this.bitStream.readBits(3);
+		this.glassesScale = this.bitStream.readBits(4);
+		this.glassesYPosition = this.bitStream.readBits(5);
+		this.moleEnabled = this.bitStream.readBoolean();
+		this.moleScale = this.bitStream.readBits(4);
+		this.moleXPosition = this.bitStream.readBits(5);
+		this.moleYPosition = this.bitStream.readBits(5);
+		this.bitStream.alignByte();
+		this.creatorName = this.bitStream.readUTF16String(0x14);
+		this.bitStream.skipInt16(); // * 0x0000 padding
+		this.bitStream.swapEndian(); // * Swap to big endian because thats how checksum is calculated here
+		this.checksum = this.bitStream.readUint16();
+		this.bitStream.swapEndian(); // * Swap back to little endian
+
+		this.validate();
+
+		if (this.checksum !== this.calculateCRC()) {
+			throw new Error("Invalid Mii checksum");
+		}
+	}
+
+	public calculateCRC(): number {
+		const view = this.bitStream.view;
+
+		// @ts-expect-error _view is private
+		const data = view._view.subarray(0, 0x5e);
+
+		let crc = 0x0000;
+
+		for (const byte of data) {
+			for (let bit = 7; bit >= 0; bit--) {
+				const flag = (crc & 0x8000) != 0;
+				crc = ((crc << 1) | ((byte >> bit) & 0x1)) ^ (flag ? 0x1021 : 0);
+			}
+		}
+
+		for (let i = 16; i > 0; i--) {
+			const flag = (crc & 0x8000) != 0;
+			crc = (crc << 1) ^ (flag ? 0x1021 : 0);
+		}
+
+		return crc & 0xffff;
+	}
+
+	public encodeStudio(): Buffer {
+		this.validate();
+
+		/*
+                Can also disable randomization with:
+
+                let miiStudioData = Buffer.alloc(0x2F);
+                let next = 256;
+
+                and removing "randomizer" and the "miiStudioData.writeUInt8(randomizer);" call
+            */
+		const miiStudioData = Buffer.alloc(0x2f);
+		const randomizer = Math.floor(256 * Math.random());
+		let next = randomizer;
+		let pos = 1;
+
+		function encodeMiiPart(partValue: number): void {
+			const encoded = (7 + (partValue ^ next)) % 256;
+			next = encoded;
+
+			miiStudioData.writeUInt8(encoded, pos);
+			pos++;
+		}
+
+		miiStudioData.writeUInt8(randomizer);
+
+		if (this.facialHairColor === 0) {
+			encodeMiiPart(8);
+		} else {
+			encodeMiiPart(this.facialHairColor);
+		}
+
+		encodeMiiPart(this.beardType);
+		encodeMiiPart(this.build);
+		encodeMiiPart(this.eyeVerticalStretch);
+		encodeMiiPart(this.eyeColor + 8);
+		encodeMiiPart(this.eyeRotation);
+		encodeMiiPart(this.eyeScale);
+		encodeMiiPart(this.eyeType);
+		encodeMiiPart(this.eyeSpacing);
+		encodeMiiPart(this.eyeYPosition);
+		encodeMiiPart(this.eyebrowVerticalStretch);
+
+		if (this.eyebrowColor === 0) {
+			encodeMiiPart(8);
+		} else {
+			encodeMiiPart(this.eyebrowColor);
+		}
+
+		encodeMiiPart(this.eyebrowRotation);
+		encodeMiiPart(this.eyebrowScale);
+		encodeMiiPart(this.eyebrowType);
+		encodeMiiPart(this.eyebrowSpacing);
+		encodeMiiPart(this.eyebrowYPosition);
+		encodeMiiPart(this.skinColor);
+		encodeMiiPart(this.makeupType);
+		encodeMiiPart(this.faceType);
+		encodeMiiPart(this.wrinklesType);
+		encodeMiiPart(this.favoriteColor);
+		encodeMiiPart(this.gender);
+
+		if (this.glassesColor == 0) {
+			encodeMiiPart(8);
+		} else if (this.glassesColor < 6) {
+			encodeMiiPart(this.glassesColor + 13);
+		} else {
+			encodeMiiPart(0);
+		}
+
+		encodeMiiPart(this.glassesScale);
+		encodeMiiPart(this.glassesType);
+		encodeMiiPart(this.glassesYPosition);
+
+		if (this.hairColor == 0) {
+			encodeMiiPart(8);
+		} else {
+			encodeMiiPart(this.hairColor);
+		}
+
+		encodeMiiPart(this.flipHair ? 1 : 0);
+		encodeMiiPart(this.hairType);
+		encodeMiiPart(this.height);
+		encodeMiiPart(this.moleScale);
+		encodeMiiPart(this.moleEnabled ? 1 : 0);
+		encodeMiiPart(this.moleXPosition);
+		encodeMiiPart(this.moleYPosition);
+		encodeMiiPart(this.mouthHorizontalStretch);
+
+		if (this.mouthColor < 4) {
+			encodeMiiPart(this.mouthColor + 19);
+		} else {
+			encodeMiiPart(0);
+		}
+
+		encodeMiiPart(this.mouthScale);
+		encodeMiiPart(this.mouthType);
+		encodeMiiPart(this.mouthYPosition);
+		encodeMiiPart(this.mustacheScale);
+		encodeMiiPart(this.mustacheType);
+		encodeMiiPart(this.mustacheYPosition);
+		encodeMiiPart(this.noseScale);
+		encodeMiiPart(this.noseType);
+		encodeMiiPart(this.noseYPosition);
+
+		return miiStudioData;
+	}
+
+	public studioUrl(
+		queryParams: {
+			type?: string;
+			expression?: string;
+			width?: number;
+			bgColor?: string;
+			clothesColor?: string;
+			cameraXRotate?: number;
+			cameraYRotate?: number;
+			cameraZRotate?: number;
+			characterXRotate?: number;
+			characterYRotate?: number;
+			characterZRotate?: number;
+			lightXDirection?: number;
+			lightYDirection?: number;
+			lightZDirection?: number;
+			lightDirectionMode?: string;
+			instanceCount?: number;
+			instanceRotationMode?: string;
+			data?: string;
+		} = STUDIO_RENDER_DEFAULTS
+	): string {
+		const params = {
+			...STUDIO_RENDER_DEFAULTS,
+			...queryParams,
+			data: this.encodeStudio().toString("hex"),
+		};
+
+		// TODO - Assert and error out instead of setting defaults?
+
+		params.type = STUDIO_RENDER_TYPES.includes(params.type as string) ? params.type : STUDIO_RENDER_DEFAULTS.type;
+		params.expression = STUDIO_RENDER_EXPRESSIONS.includes(params.expression as string) ? params.expression : STUDIO_RENDER_DEFAULTS.expression;
+		params.width = Util.clamp(params.width, 512);
+		params.bgColor = STUDIO_BG_COLOR_REGEX.test(params.bgColor as string) ? params.bgColor : STUDIO_RENDER_DEFAULTS.bgColor;
+		params.clothesColor = STUDIO_RENDER_CLOTHES_COLORS.includes(params.clothesColor) ? params.clothesColor : STUDIO_RENDER_DEFAULTS.clothesColor;
+		params.cameraXRotate = Util.clamp(params.cameraXRotate, 359);
+		params.cameraYRotate = Util.clamp(params.cameraYRotate, 359);
+		params.cameraZRotate = Util.clamp(params.cameraZRotate, 359);
+		params.characterXRotate = Util.clamp(params.characterXRotate, 359);
+		params.characterYRotate = Util.clamp(params.characterYRotate, 359);
+		params.characterZRotate = Util.clamp(params.characterZRotate, 359);
+		params.lightXDirection = Util.clamp(params.lightXDirection, 359);
+		params.lightYDirection = Util.clamp(params.lightYDirection, 359);
+		params.lightZDirection = Util.clamp(params.lightZDirection, 359);
+		params.lightDirectionMode = STUDIO_RENDER_LIGHT_DIRECTION_MODS.includes(params.lightDirectionMode)
+			? params.lightDirectionMode
+			: STUDIO_RENDER_DEFAULTS.lightDirectionMode;
+		params.instanceCount = Util.clamp(params.instanceCount, 1, 16);
+		params.instanceRotationMode = STUDIO_RENDER_INSTANCE_ROTATION_MODES.includes(params.instanceRotationMode)
+			? params.instanceRotationMode
+			: STUDIO_RENDER_DEFAULTS.instanceRotationMode;
+
+		// converts non-string params to strings
+		const query = new URLSearchParams(Object.fromEntries(Object.entries(params).map(([key, value]) => [key, value.toString()])));
+
+		if (params.lightDirectionMode === "none") {
+			query.delete("lightDirectionMode");
+			query.delete("lightXDirection");
+			query.delete("lightYDirection");
+			query.delete("lightZDirection");
+		}
+
+		return `${STUDIO_RENDER_URL_BASE}?${query.toString()}`;
+	}
+}

src/utils/mii.js/util.ts

@@ -0,0 +1,24 @@
+// Stolen from https://github.com/PretendoNetwork/mii-js/
+
+export default class Util {
+	public static inRange(val: number, range: number[]): boolean {
+		return range.includes(val);
+	}
+
+	public static clamp(val: number, min: number, max?: number): number {
+		if (max === undefined) {
+			max = min;
+			min = 0;
+		}
+
+		return Math.min(Math.max(val, min), max);
+	}
+
+	public static range(start: number, end?: number): number[] {
+		if (end === undefined) {
+			end = start;
+			start = 0;
+		}
+		return Array.from({ length: end - start }, (_, i) => i + start);
+	}
+}