@aidulcandra/simple-wa-bot/utils.js

A baileys wrapper module

const {Image} = require('node-webpmux')
const {randomBytes} = require('crypto')
const {fileTypeFromBuffer} = require('file-type')
const {TextEncoder} = require("util")
const {tmpdir} = require("os")
const ffmpeg = require("fluent-ffmpeg")
const sharp = require('sharp')
const {existsSync, read} = require('fs')
const {writeFile, readFile, unlink} = require('fs/promises')

async function createSticker (input, options) {
    const buffer = await parseInput(input)
	const id = randomBytes(32).toString('hex')
	const metadata = {
		quality: options?.quality || 100,
		type: ['default','crop','full','circle','rounded'].includes(options?.type) ? options.type : 'default',
		background: options?.background || 'transparent'
	}
	const stickerData = JSON.stringify({
		'sticker-pack-id': id,
		'sticker-pack-name': options?.pack || '',
		'sticker-pack-publisher': options?.author || '',
		emojis: options?.categories || []
	})
	const mime = await fileTypeFromBuffer(buffer).then(ft => ft.mime)
	const isVideo = mime.startsWith('video')
    let image = isVideo
		? await videoToGif(buffer)
		: buffer
    const isWebp = mime.includes('webp')
    const isAnimated = isVideo || isWebp || mime.includes('gif')
	
    if (isAnimated && ['crop','circle','rounded'].includes(metadata.type)) {
        const filename = `${tmpdir()}/${Math.random().toString(36)}.webp`
        await writeFile(filename, image)
        image = await crop(filename, isWebp ? 100 : metadata.quality)
        await unlink(filename)
    }
	
	const img = sharp(image, {animated: isAnimated}).toFormat('webp')
    switch (metadata.type) {
        case 'crop': img.resize(512, 512, {fit: 'cover', position: sharp.strategy.attention}); break
        case 'full': img.resize(512, 512, {fit: 'contain', background: metadata.background}); break
        case 'circle': img.resize(512, 512, {fit: 'cover'}).composite([
            {
                input: Buffer.from(`<svg width="512" height="512"><circle cx="256" cy="256" r="256" fill="black"/></svg>`),
                blend: 'dest-in',
                gravity: 'northeast',
                tile: true
            }
        ]); break
        case 'rounded': img.resize(512, 512, {fit: 'cover'}).composite([
            {
                input: Buffer.from(`<svg width="512" height="512"><rect rx="50" ry="50" width="512" height="512" fill="black"/></svg>`),
                blend: 'dest-in',
                gravity: 'northeast',
                tile: true
            }
        ]); break
    }
	const converted = await img.webp({quality:metadata.quality,lossless:false}).toBuffer()
	
	const exif = Buffer.concat([
		Buffer.from([0x49, 0x49, 0x2a, 0x00, 0x08, 0x00, 0x00, 0x00, 0x01, 0x00, 0x41, 0x57, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x16, 0x00, 0x00, 0x00]),
		Buffer.from(stickerData, 'utf-8')
	])
	exif.writeUIntLE(new TextEncoder().encode(stickerData).length, 14, 4)
	
	const media = new Image()
	await media.load(converted)
	media.exif = exif
	
	const sticker = await media.save(null)
	stickerMessage = {sticker}

    return stickerMessage
}

async function videoToGif(buffer) {
	const filename = `${tmpdir()}/${Math.random().toString(36)}`
    const [video, gif] = ['video', 'gif'].map((ext) => `${filename}.${ext}`)
    await writeFile(video, buffer)
    await new Promise((resolve) => {
        ffmpeg(video).save(gif).on('end', resolve)
    })
    const b = await readFile(gif)
    ;[video, gif].forEach((file) => unlink(file))
    return b
}

async function crop (filename, quality = 100) {
    const file = await new Promise(resolve => {
        const name = `${tmpdir()}/${Math.random().toString(36)}.webp`
        ffmpeg(filename)
            .outputOptions([
                '-vcodec', 'libwebp', 
                '-vf', `crop='min(min(iw\,ih)\,256)':'min(min(iw\,ih)\,256)',scale=512:512,setsar=1,fps=15`,
                '-loop', '0', 
                '-preset', 'picture', 
                '-an', 
                '-vsync', '0',
                '-s', '512:512',
                '-qscale', `${quality}`
            ])
            .save(name)
            .on('end', () => resolve(name))
    })
    const b = await readFile(file)
    await unlink(file)
    return b
}

async function parseInput (input) {
    return Buffer.isBuffer(input)
        ? input
        : input.trim().startsWith('<svg')
            ? Buffer.from(input)
            : existsSync(input)
                ? readFile(input)
                : fetch(input).then(r=>r.arrayBuffer()).then(ab => Buffer.from(ab))
}

module.exports = {createSticker}