fix(sticker): align sticker pack with WABA Android behavior (Frida capture)

Align sticker pack implementation with WhatsApp Business Android (WABA) behavior captured via Frida reverse engineering. Fixes 4 critical issues identified in field-by-field comparison with WABA's sticker DB schema. - Add Lottie/WAS format detection (isLottieBuffer) for animated stickers - Fix mimetype: use 'application/was' for Lottie, 'image/webp' for WebP - Fix isLottie: auto-detect instead of hardcoded false - Fix tray icon: convert cover to PNG format (WABA uses .png, not .webp) - Add 512x512 dimension enforcement for WebP stickers (WABA standard) - Add isLottie field to Sticker type for explicit format override Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-04 09:45:55 -03:00
parent cf72068b6c
commit 4fa7d4ee11
2 changed files with 106 additions and 16 deletions
@@ -54,12 +54,14 @@ export type WAMediaUpload = Buffer | WAMediaPayloadStream | WAMediaPayloadURL
 * Individual sticker in a sticker pack
 */
 export type Sticker = {
-	/** Buffer, Stream or URL of the sticker image (will be converted to WebP if needed) */
+	/** Buffer, Stream or URL of the sticker image (WebP or Lottie/WAS format) */
 	data: WAMediaUpload
 	/** Array of emojis associated with this sticker (max 3 recommended per WhatsApp standards) */
 	emojis?: string[]
 	/** Accessibility label for screen readers (max 125 chars for static, 255 for animated) */
 	accessibilityLabel?: string
+	/** Force Lottie format detection (auto-detected if omitted) */
+	isLottie?: boolean
 }

 /**
@@ -2,6 +2,7 @@ import { Boom } from '@hapi/boom'
 import { createHash } from 'crypto'
 import { zipSync } from 'fflate'
 import { promises as fs } from 'fs'
+import { gunzipSync } from 'zlib'
 import { proto } from '../../WAProto/index.js'
 import type { MediaType } from '../Defaults/index.js'
 import type { StickerPack, WAMediaUpload, WAMediaUploadFunction } from '../Types/Message.js'
@@ -101,6 +102,48 @@ export const isAnimatedWebP = (buffer: Buffer): boolean => {
 	return false
 }

+/**
+ * Detecta se um buffer é Lottie JSON (raw ou gzip-compressed/WAS)
+ *
+ * WABA usa mimetype `application/was` para stickers Lottie.
+ * WAS (WhatsApp Animated Sticker) = gzip-compressed Lottie JSON.
+ *
+ * Detecção:
+ * - Gzip (0x1f 0x8b): descomprime e verifica se é Lottie JSON
+ * - JSON bruto: verifica campos Lottie obrigatórios (v, ip, op, layers)
+ *
+ * @param buffer - Buffer to check
+ * @returns true if buffer is Lottie/WAS format
+ */
+export const isLottieBuffer = (buffer: Buffer): boolean => {
+	if (buffer.length < 2) return false
+
+	let jsonBuffer: Buffer
+
+	// Check if gzip-compressed (WAS format)
+	if (buffer[0] === 0x1f && buffer[1] === 0x8b) {
+		try {
+			jsonBuffer = gunzipSync(buffer) as Buffer
+		} catch {
+			return false
+		}
+	} else if (buffer[0] === 0x7b) {
+		// Starts with '{' - could be raw Lottie JSON
+		jsonBuffer = buffer
+	} else {
+		return false
+	}
+
+	// Validate Lottie JSON structure: must have v, ip, op, layers
+	try {
+		const str = jsonBuffer.toString('utf8', 0, Math.min(jsonBuffer.length, 4096))
+		// Quick check for required Lottie fields
+		return str.includes('"v"') && str.includes('"layers"') && (str.includes('"ip"') || str.includes('"op"'))
+	} catch {
+		return false
+	}
+}
+
 /**
 * Converte uma imagem para WebP usando Sharp
 * Preserva o buffer original se já for WebP para manter EXIF e animações
@@ -114,12 +157,18 @@ export const isAnimatedWebP = (buffer: Buffer): boolean => {
 const convertToWebP = async (
 	buffer: Buffer,
 	logger?: ILogger
-): Promise<{ webpBuffer: Buffer; isAnimated: boolean }> => {
+): Promise<{ webpBuffer: Buffer; isAnimated: boolean; isLottie: boolean }> => {
+	// Lottie/WAS: passthrough sem converter (formato vetorial, mimetype=application/was)
+	if (isLottieBuffer(buffer)) {
+		logger?.trace('Input is Lottie/WAS format, preserving original buffer')
+		return { webpBuffer: buffer, isAnimated: true, isLottie: true }
+	}
+
 	// Se já é WebP, preserva o buffer original (mantém EXIF e animações)
 	if (isWebPBuffer(buffer)) {
 		const isAnimated = isAnimatedWebP(buffer)
 		logger?.trace({ isAnimated }, 'Input is already WebP, preserving original buffer')
-		return { webpBuffer: buffer, isAnimated }
+		return { webpBuffer: buffer, isAnimated, isLottie: false }
 	}

 	// Tenta usar Sharp para converter
@@ -135,7 +184,7 @@ const convertToWebP = async (
 	logger?.trace('Converting image to WebP using Sharp')
 	const webpBuffer = await lib.sharp.default(buffer).webp().toBuffer()

-	return { webpBuffer, isAnimated: false }
+	return { webpBuffer, isAnimated: false, isLottie: false }
 }

 /**
@@ -464,9 +513,33 @@ export const prepareStickerPackMessage = async (
 				// Obtém buffer do sticker
 				const buffer = await mediaToBuffer(sticker.data, `sticker ${i + 1}`)

-				// Converte para WebP
+				// Detecta formato e converte se necessário
 				// eslint-disable-next-line prefer-const
-				let { webpBuffer, isAnimated } = await convertToWebP(buffer, logger)
+				let { webpBuffer, isAnimated, isLottie } = await convertToWebP(buffer, logger)
+
+				// Honor explicit isLottie flag from user input
+				if (sticker.isLottie !== undefined) {
+					isLottie = sticker.isLottie
+				}
+
+				// WABA: Enforce 512x512 dimensions for WebP stickers (Lottie is vector, skip)
+				if (!isLottie && isWebPBuffer(webpBuffer)) {
+					const lib = await getImageProcessingLibrary()
+					if (lib?.sharp) {
+						const metadata = await lib.sharp.default(webpBuffer).metadata()
+						if (metadata.width !== 512 || metadata.height !== 512) {
+							logger?.trace(
+								{ index: i, width: metadata.width, height: metadata.height },
+								'Resizing sticker to 512x512 (WABA standard)'
+							)
+							webpBuffer = await lib.sharp
+								.default(webpBuffer)
+								.resize(512, 512, { fit: 'contain', background: { r: 0, g: 0, b: 0, alpha: 0 } })
+								.webp()
+								.toBuffer()
+						}
+					}
+				}

 				// ENHANCEMENT: Auto-compression if exceeds 1MB (try quality 70, then 50)
 				const MAX_STICKER_SIZE = 1024 * 1024 // 1MB
@@ -547,12 +620,13 @@ export const prepareStickerPackMessage = async (
 					)
 				}

-				// Gera nome do arquivo: hash.webp (deduplicação automática)
+				// Gera nome do arquivo: hash.webp ou hash.was (WABA: plain_file_hash.ext)
 				const sha256Hash = generateSha256Hash(webpBuffer)
-				const fileName = `${sha256Hash}.webp`
+				const extension = isLottie ? 'was' : 'webp'
+				const fileName = `${sha256Hash}.${extension}`

 				logger?.trace(
-					{ index: i, fileName, sizeKB: finalSizeKB.toFixed(2), isAnimated },
+					{ index: i, fileName, sizeKB: finalSizeKB.toFixed(2), isAnimated, isLottie },
 					'Sticker processed successfully'
 				)

@@ -560,6 +634,7 @@ export const prepareStickerPackMessage = async (
 					fileName,
 					webpBuffer,
 					isAnimated,
+					isLottie,
 					emojis: sticker.emojis || [],
 					accessibilityLabel: sticker.accessibilityLabel
 				}
@@ -578,7 +653,7 @@ export const prepareStickerPackMessage = async (
 	for (const result of processedStickers) {
 		if (!result) continue

-		const { fileName, webpBuffer, isAnimated, emojis, accessibilityLabel } = result
+		const { fileName, webpBuffer, isAnimated, isLottie, emojis, accessibilityLabel } = result

 		// SECURITY FIX #7: Check if this hash already exists (duplicate sticker)
 		const existingMetadata = metadataByHash.get(fileName)
@@ -605,13 +680,14 @@ export const prepareStickerPackMessage = async (
 			// New sticker - add to ZIP and create metadata
 			stickerData[fileName] = [new Uint8Array(webpBuffer), { level: 0 as 0 }]

+			// WABA: mimetype é 'application/was' para Lottie, 'image/webp' para WebP
 			const metadata: proto.Message.StickerPackMessage.ISticker = {
 				fileName,
 				isAnimated,
 				emojis,
 				accessibilityLabel,
-				isLottie: false,
-				mimetype: 'image/webp'
+				isLottie,
+				mimetype: isLottie ? 'application/was' : 'image/webp'
 			}

 			metadataByHash.set(fileName, metadata)
@@ -636,10 +712,22 @@ export const prepareStickerPackMessage = async (
 		logger?.trace('Processing cover image')
 		coverBuffer = await mediaToBuffer(cover, 'cover image')

-		// Converte cover para WebP e adiciona ao ZIP
-		const result = await convertToWebP(coverBuffer, logger)
-		coverWebP = result.webpBuffer
-		coverFileName = `${stickerPackId}.webp`
+		// WABA: Tray icon uses PNG format (installed_tray_image_id = .png)
+		const lib = await getImageProcessingLibrary()
+		if (lib?.sharp) {
+			// Convert cover to PNG and resize to 96x96 (WABA tray icon standard)
+			coverWebP = await lib.sharp
+				.default(coverBuffer)
+				.resize(96, 96, { fit: 'contain', background: { r: 0, g: 0, b: 0, alpha: 0 } })
+				.png()
+				.toBuffer()
+		} else {
+			// Fallback: convert to WebP if Sharp not available
+			const result = await convertToWebP(coverBuffer, logger)
+			coverWebP = result.webpBuffer
+		}
+
+		coverFileName = `${stickerPackId}.png`
 		stickerData[coverFileName] = [new Uint8Array(coverWebP), { level: 0 as 0 }]
 	} catch (error) {
 		throw new Boom(`Failed to process cover image: ${(error as Error).message}`, {