fix: jpg解密修复

electron/services/imageDecryptService.ts

@@ -8,6 +8,19 @@ import { Worker } from 'worker_threads'
 import { ConfigService } from './config'
 import { wcdbService } from './wcdbService'
 
+// 获取 ffmpeg-static 的路径
+function getStaticFfmpegPath(): string | null {
+  try {
+    const ffmpegStatic = require('ffmpeg-static')
+    if (typeof ffmpegStatic === 'string') {
+      return ffmpegStatic
+    }
+    return null
+  } catch {
+    return null
+  }
+}
+
 type DecryptResult = {
   success: boolean
   localPath?: string
@@ -238,20 +251,39 @@ export class ImageDecryptService {
       const aesKey = this.resolveAesKey(aesKeyRaw)
 
       this.logInfo('开始解密DAT文件', { datPath, xorKey, hasAesKey: !!aesKey })
-      const decrypted = await this.decryptDatAuto(datPath, xorKey, aesKey)
+      let decrypted = await this.decryptDatAuto(datPath, xorKey, aesKey)
 
-      const ext = this.detectImageExtension(decrypted) || '.jpg'
+      // 检查是否是 wxgf 格式，如果是则尝试提取真实图片数据
+      const wxgfResult = await this.unwrapWxgf(decrypted)
+      decrypted = wxgfResult.data
 
-      const outputPath = this.getCacheOutputPathFromDat(datPath, ext, payload.sessionId)
+      let ext = this.detectImageExtension(decrypted)
+      
+      // 如果是 wxgf 格式且没检测到扩展名
+      if (wxgfResult.isWxgf && !ext) {
+        ext = '.hevc'
+      }
+      
+      const finalExt = ext || '.jpg'
+
+      const outputPath = this.getCacheOutputPathFromDat(datPath, finalExt, payload.sessionId)
       await writeFile(outputPath, decrypted)
       this.logInfo('解密成功', { outputPath, size: decrypted.length })
 
+      // 对于 hevc 格式，返回错误提示
+      if (finalExt === '.hevc') {
+        return { 
+          success: false, 
+          error: '此图片为微信新格式(wxgf)，需要安装 ffmpeg 才能显示',
+          isThumb: this.isThumbnailPath(datPath)
+        }
+      }
       const isThumb = this.isThumbnailPath(datPath)
       this.cacheResolvedPaths(cacheKey, payload.imageMd5, payload.imageDatName, outputPath)
       if (!isThumb) {
         this.clearUpdateFlags(cacheKey, payload.imageMd5, payload.imageDatName)
       }
-      const dataUrl = this.bufferToDataUrl(decrypted, ext)
+      const dataUrl = this.bufferToDataUrl(decrypted, finalExt)
       const localPath = dataUrl || this.filePathToUrl(outputPath)
       this.emitCacheResolved(payload, cacheKey, localPath)
       return { success: true, localPath, isThumb }
@@ -1406,6 +1438,152 @@ export class ImageDecryptService {
     return mostCommonKey
   }
 
+  /**
+   * 解包 wxgf 格式
+   * wxgf 是微信的图片格式，内部使用 HEVC 编码
+   */
+  private async unwrapWxgf(buffer: Buffer): Promise<{ data: Buffer; isWxgf: boolean }> {
+    // 检查是否是 wxgf 格式 (77 78 67 66 = "wxgf")
+    if (buffer.length < 20 || 
+        buffer[0] !== 0x77 || buffer[1] !== 0x78 || 
+        buffer[2] !== 0x67 || buffer[3] !== 0x66) {
+      return { data: buffer, isWxgf: false }
+    }
+    
+    // 先尝试搜索内嵌的传统图片签名
+    for (let i = 4; i < Math.min(buffer.length - 12, 4096); i++) {
+      if (buffer[i] === 0xff && buffer[i + 1] === 0xd8 && buffer[i + 2] === 0xff) {
+        return { data: buffer.subarray(i), isWxgf: false }
+      }
+      if (buffer[i] === 0x89 && buffer[i + 1] === 0x50 && 
+          buffer[i + 2] === 0x4e && buffer[i + 3] === 0x47) {
+        return { data: buffer.subarray(i), isWxgf: false }
+      }
+    }
+    
+    // 提取 HEVC NALU 裸流
+    const hevcData = this.extractHevcNalu(buffer)
+    if (!hevcData || hevcData.length < 100) {
+      return { data: buffer, isWxgf: true }
+    }
+    
+    // 尝试用 ffmpeg 转换
+    try {
+      const jpgData = await this.convertHevcToJpg(hevcData)
+      if (jpgData && jpgData.length > 0) {
+        return { data: jpgData, isWxgf: false }
+      }
+    } catch {
+      // ffmpeg 转换失败
+    }
+    
+    return { data: hevcData, isWxgf: true }
+  }
+
+  /**
+   * 从 wxgf 数据中提取 HEVC NALU 裸流
+   */
+  private extractHevcNalu(buffer: Buffer): Buffer | null {
+    const nalUnits: Buffer[] = []
+    let i = 4
+    
+    while (i < buffer.length - 4) {
+      if (buffer[i] === 0x00 && buffer[i + 1] === 0x00 && 
+          buffer[i + 2] === 0x00 && buffer[i + 3] === 0x01) {
+        let nalStart = i
+        let nalEnd = buffer.length
+        
+        for (let j = i + 4; j < buffer.length - 3; j++) {
+          if (buffer[j] === 0x00 && buffer[j + 1] === 0x00) {
+            if (buffer[j + 2] === 0x01 || 
+                (buffer[j + 2] === 0x00 && j + 3 < buffer.length && buffer[j + 3] === 0x01)) {
+              nalEnd = j
+              break
+            }
+          }
+        }
+        
+        const nalUnit = buffer.subarray(nalStart, nalEnd)
+        if (nalUnit.length > 3) {
+          nalUnits.push(nalUnit)
+        }
+        i = nalEnd
+      } else {
+        i++
+      }
+    }
+    
+    if (nalUnits.length === 0) {
+      for (let j = 4; j < buffer.length - 4; j++) {
+        if (buffer[j] === 0x00 && buffer[j + 1] === 0x00 && 
+            buffer[j + 2] === 0x00 && buffer[j + 3] === 0x01) {
+          return buffer.subarray(j)
+        }
+      }
+      return null
+    }
+    
+    return Buffer.concat(nalUnits)
+  }
+
+  /**
+   * 获取 ffmpeg 可执行文件路径
+   */
+  private getFfmpegPath(): string {
+    const staticPath = getStaticFfmpegPath()
+    if (staticPath) {
+      const unpackedPath = staticPath.replace('app.asar', 'app.asar.unpacked')
+      if (existsSync(unpackedPath)) {
+        return unpackedPath
+      }
+      if (existsSync(staticPath)) {
+        return staticPath
+      }
+    }
+    return 'ffmpeg'
+  }
+
+  /**
+   * 使用 ffmpeg 将 HEVC 裸流转换为 JPG
+   */
+  private convertHevcToJpg(hevcData: Buffer): Promise<Buffer | null> {
+    const ffmpeg = this.getFfmpegPath()
+    
+    return new Promise((resolve) => {
+      const { spawn } = require('child_process')
+      const chunks: Buffer[] = []
+      
+      const proc = spawn(ffmpeg, [
+        '-hide_banner',
+        '-loglevel', 'error',
+        '-f', 'hevc',
+        '-i', 'pipe:0',
+        '-vframes', '1',
+        '-q:v', '3',
+        '-f', 'mjpeg',
+        'pipe:1'
+      ], { 
+        stdio: ['pipe', 'pipe', 'pipe'],
+        windowsHide: true
+      })
+      
+      proc.stdout.on('data', (chunk: Buffer) => chunks.push(chunk))
+      
+      proc.on('close', (code: number) => {
+        if (code === 0 && chunks.length > 0) {
+          resolve(Buffer.concat(chunks))
+        } else {
+          resolve(null)
+        }
+      })
+      
+      proc.on('error', () => resolve(null))
+      
+      proc.stdin.write(hevcData)
+      proc.stdin.end()
+    })
+  }
+
   // 保留原有的解密到文件方法（用于兼容）
   async decryptToFile(inputPath: string, outputPath: string, xorKey: number, aesKey?: Buffer): Promise<void> {
     const version = this.getDatVersion(inputPath)