Fermi/emoji-packer.cts

const res = await fetch(
	"https://raw.githubusercontent.com/muan/unicode-emoji-json/refs/heads/main/data-by-group.json",
);
const emojilist = (await res.json()) as {
	name: string;
	slug: string;
	emojis: {
		emoji: string;
		name: string;
		slug: string;
		skin_tone_support: boolean;
	}[];
}[];
console.log(emojilist);

const buffer = new ArrayBuffer(2 ** 26);
const view = new DataView(buffer, 0);
let i = 0;
function write16(numb: number) {
	view.setUint16(i, numb);
	i += 2;
}
function write8(numb: number) {
	view.setUint8(i, numb);
	i += 1;
}
function writeString8(str: string) {
	const encode = new TextEncoder().encode(str);
	write8(encode.length);
	for (const thing of encode) {
		write8(thing);
	}
}
function writeString16(str: string) {
	const encode = new TextEncoder().encode(str);
	write16(encode.length);
	for (const thing of encode) {
		write8(thing);
	}
}
function writeStringNo(str: string) {
	const encode = new TextEncoder().encode(str);
	for (const thing of encode) {
		write8(thing);
	}
}

write16(emojilist.length);
for (const thing of emojilist) {
	writeString16(thing.name);
	write16(thing.emojis.length);
	for (const emoji of thing.emojis) {
		writeString8(emoji.name);
		write8(new TextEncoder().encode(emoji.emoji).length + 128 * +emoji.skin_tone_support);
		writeStringNo(emoji.emoji);
	}
}
const out = new ArrayBuffer(i);
const ar = new Uint8Array(out);
const br = new Uint8Array(buffer);
for (const thing in ar) {
	ar[thing] = br[thing];
}
console.log(i, ar);

function decodeEmojiList(buffer: ArrayBuffer) {
	const view = new DataView(buffer, 0);
	let i = 0;
	function read16() {
		const int = view.getUint16(i);
		i += 2;
		return int;
	}
	function read8() {
		const int = view.getUint8(i);
		i += 1;
		return int;
	}
	function readString8() {
		return readStringNo(read8());
	}
	function readString16() {
		return readStringNo(read16());
	}
	function readStringNo(length) {
		const array = new Uint8Array(length);

		for (let i = 0; i < length; i++) {
			array[i] = read8();
		}
		//console.log(array);
		return new TextDecoder("utf-8").decode(array.buffer);
	}
	const build: {
		name: string;
		emojis: {name: string; skin_tone_support: boolean; emoji: string}[];
	}[] = [];
	let cats = read16();

	for (; cats !== 0; cats--) {
		const name = readString16();
		const emojis: {name: string; skin_tone_support: boolean; emoji: string}[] = [];
		let emojinumber = read16();
		for (; emojinumber !== 0; emojinumber--) {
			//console.log(emojis);
			const name = readString8();
			const len = read8();
			const skin_tone_support = len > 127;
			const emoji = readStringNo(len - +skin_tone_support * 128);
			emojis.push({
				name,
				skin_tone_support,
				emoji,
			});
		}
		build.push({
			name,
			emojis,
		});
	}
	return build;
}
console.log(JSON.stringify(decodeEmojiList(out)));

const fs = require("node:fs");
fs.writeFile("./webpage/emoji.bin", new Uint8Array(out), (_) => {});