From 48186085d88754d4cbd122e3a8edd6f33cb62530 Mon Sep 17 00:00:00 2001
From: Victor_Jay <ovoex.cn@gmail.com>
Date: Sun, 31 May 2026 03:12:10 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20=E5=9B=9E=E9=80=80=E5=AD=98=E5=82=A8?=
 =?UTF-8?q?=E8=B7=AF=E5=BE=84=E4=B9=9F=E8=A7=A3=E7=A0=81=E9=87=8D=E7=BC=96?=
 =?UTF-8?q?=E7=A0=81=EF=BC=8C=E5=BD=BB=E5=BA=95=E5=89=A5=E7=A6=BB=20EXIF/?=
 =?UTF-8?q?=E5=85=83=E6=95=B0=E6=8D=AE?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- fallback 路径不再直接写原始上传字节，而是解码后重编码
- JPEG: decode → jpeg.Encode(quality 92)，剥离 EXIF/GPS/注释
- PNG: decode → png.Encode，剥离元数据块
- WebP: decode → webp.Encode(quality 80)，剥离元数据
- GIF 例外：重编码会丢失动画帧，仅解码验证后原样存储
- 导入 jpeg/png 从空白导入改为命名导入，以使用 Encode 函数
---
 internal/controller/post_controller.go | 37 ++++++++++++++++++++++----
 1 file changed, 32 insertions(+), 5 deletions(-)

diff --git a/internal/controller/post_controller.go b/internal/controller/post_controller.go
index 8a8eb68..49c39e8 100644
--- a/internal/controller/post_controller.go
+++ b/internal/controller/post_controller.go
@@ -5,9 +5,9 @@ import (
 	"errors"
 	"fmt"
 	"image"
-	_ "image/gif"
-	_ "image/jpeg"
-	_ "image/png"
+	"image/jpeg"
+	"image/png"
+	_ "image/gif" // 仅注册 GIF 解码器，不重编码（会丢失动画）
 	"io"
 	"net/http"
 	"os"
@@ -449,11 +449,38 @@ func (ctrl *PostController) UploadImage(c *gin.Context) {
 		}
 	}
 
-	// 原格式存储（GIF / 已有 WebP / 二分压缩仍超原文件大小）
+	// 回退存储：重新编码以剥离 EXIF/元数据（GIF 例外：重编码会丢失动画）
 	if savePath == "" {
+		dataOut := data
+
+		if isJPEGPNG || isWebP {
+			var decImg image.Image
+			var decErr error
+			if isWebP {
+				decImg, decErr = webp.Decode(bytes.NewReader(data))
+			} else {
+				decImg, _, decErr = image.Decode(bytes.NewReader(data))
+			}
+			if decErr == nil {
+				var buf bytes.Buffer
+				var encErr error
+				switch {
+				case isWebP:
+					encErr = webp.Encode(&buf, decImg, &webp.Options{Quality: 80})
+				case ext == ".png":
+					encErr = png.Encode(&buf, decImg)
+				default:
+					encErr = jpeg.Encode(&buf, decImg, &jpeg.Options{Quality: 92})
+				}
+				if encErr == nil && buf.Len() > 0 {
+					dataOut = buf.Bytes()
+				}
+			}
+		}
+
 		filename := fmt.Sprintf("%d_%d%s", uid, ts, ext)
 		savePath = filepath.Join(storageDir, filename)
-		if err := os.WriteFile(savePath, data, 0644); err != nil {
+		if err := os.WriteFile(savePath, dataOut, 0644); err != nil {
 			common.Error(c, http.StatusInternalServerError, "保存图片失败")
 			return
 		}