feat(backend): 公开页 SSR 化——商品页/店铺页后端直出，顾客动线零 Flutter

- /product/:public_id 从「Flutter 壳注入 OG」改为 go:embed 模板直出轻量页
  （~5KB vs 12.5MB 首包，3Mbps 带宽下 30s → <0.5s），OG 分享卡片行为不变
- 新增 /shop/:shop_code 店铺公开页短链：搜索(?q=)+分页(?page=)，商品卡互跳
- 数据装配与公开 API 共用（loadPublicProduct / queryShopProducts），口径零漂移
- 图片异步拉取：首图 decoding=async、其余 loading=lazy
- 设计：docs/design/public-page-speedup.html

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JJ1g8XV1YhhmHRzhwWEW7o

backend/internal/handler/public.go

@@ -5,15 +5,12 @@ import (
 	"fmt"
 	"html"
 	"net/http"
-	"os"
-	"regexp"
 	"strconv"
 	"strings"
 
 	"github.com/gin-gonic/gin"
 	"gorm.io/gorm"
 
-	"github.com/wangjia/jiu/backend/config"
 	"github.com/wangjia/jiu/backend/internal/model"
 )
 
@@ -32,75 +29,42 @@ func NewPublicHandler(db *gorm.DB) *PublicHandler {
 }
 
 // GetProduct GET /api/v1/public/products/:public_id (no auth)
+// 数据装配走 loadPublicProduct（与 SSR 商品页共用，公开字段口径单一实现）。
 func (h *PublicHandler) GetProduct(c *gin.Context) {
-	publicID := c.Param("public_id")
-
-	var product model.Product
-	if err := h.db.Where("public_id = ? AND deleted_at IS NULL", publicID).
-		Preload("Images").
-		Preload("Origin").
-		Preload("ShelfLife").
-		Preload("Storage").
-		Preload("DescriptionDoc").
-		First(&product).Error; err != nil {
+	d, err := h.loadPublicProduct(c.Param("public_id"))
+	if err != nil {
 		c.JSON(http.StatusNotFound, gin.H{"error": "not found"})
 		return
 	}
+	product := d.Product
 
-	// Fetch shop public info
-	var shop model.Shop
 	shopData := gin.H{}
-	if err := h.db.Where("id = ?", product.ShopID).First(&shop).Error; err == nil {
+	if d.HasShop {
 		shopData = gin.H{
-			"name":           shop.Name,
-			"code":           shop.Code,
-			"address":        shop.Address,
-			"phone":          shop.Phone,
-			"business_hours": shop.BusinessHours,
-			"wechat_id":      shop.WechatID,
+			"name":           d.Shop.Name,
+			"code":           d.Shop.Code,
+			"address":        d.Shop.Address,
+			"phone":          d.Shop.Phone,
+			"business_hours": d.Shop.BusinessHours,
+			"wechat_id":      d.Shop.WechatID,
 		}
 	}
 
-	// Fetch latest inventory batch for this product
-	var inv model.Inventory
 	batchData := gin.H(nil)
-	if err := h.db.Where("product_id = ? AND quantity > 0 AND deleted_at IS NULL", product.ID).
-		Order("created_at DESC").
-		First(&inv).Error; err == nil {
+	if d.Batch != nil {
 		var pdStr *string
-		if inv.ProductionDate != nil {
-			s := inv.ProductionDate.Time.Format("2006-01-02")
+		if d.Batch.ProductionDate != nil {
+			s := d.Batch.ProductionDate.Time.Format("2006-01-02")
 			pdStr = &s
 		}
 		batchData = gin.H{
 			"production_date": pdStr,
-			"batch_no":        inv.BatchNo,
-			"in_stock_date":   inv.CreatedAt.Format("2006-01-02"),
-			"quantity":        inv.Quantity,
+			"batch_no":        d.Batch.BatchNo,
+			"in_stock_date":   d.Batch.CreatedAt.Format("2006-01-02"),
+			"quantity":        d.Batch.Quantity,
 		}
 	}
 
-	// 产地：空串表示无，前端不展示该行
-	origin := ""
-	if product.Origin != nil {
-		origin = product.Origin.Name
-	}
-
-	// 保质期：无关联时用默认话术
-	shelfLife := defaultShelfLife
-	if product.ShelfLife != nil {
-		shelfLife = product.ShelfLife.Name
-	}
-
-	// 储存方式：无关联时用默认话术
-	storage := defaultStorage
-	if product.Storage != nil {
-		storage = product.Storage.Name
-	}
-
-	// 介绍三级回退：描述文档 → 旧 Description → 通用中性兜底
-	descTitle, descBody, descKeywords := buildDescription(product)
-
 	c.JSON(http.StatusOK, gin.H{
 		"data": gin.H{
 			"id":                   product.ID,
@@ -112,12 +76,12 @@ func (h *PublicHandler) GetProduct(c *gin.Context) {
 			"brand":                product.Brand,
 			"unit":                 product.Unit,
 			"sale_price":           product.SalePrice,
-			"description":          descBody,
-			"description_title":    descTitle,
-			"description_keywords": descKeywords,
-			"origin":               origin,
-			"shelf_life":           shelfLife,
-			"storage":              storage,
+			"description":          d.DescBody,
+			"description_title":    d.DescTitle,
+			"description_keywords": d.Keywords,
+			"origin":               d.Origin,
+			"shelf_life":           d.ShelfLife,
+			"storage":              d.Storage,
 			"images":               product.Images,
 			"shop":                 shopData,
 			"batch":                batchData,
@@ -237,75 +201,13 @@ func (h *PublicHandler) ListShopProducts(c *gin.Context) {
 		pageSize = 20
 	}
 
-	// 仅列「有库存」的商品：JOIN 库存按 product 聚合（数量>0）的子查询。
-	stockSub := h.db.Model(&model.Inventory{}).
-		Select("product_id, SUM(quantity) AS qty").
-		Where("shop_id = ? AND deleted_at IS NULL AND quantity > 0", shop.ID).
-		Group("product_id")
-
-	query := h.db.Model(&model.Product{}).
-		Joins("JOIN (?) AS stk ON stk.product_id = products.id", stockSub).
-		Where("products.shop_id = ? AND products.public_id IS NOT NULL AND products.public_id != '' AND products.deleted_at IS NULL", shop.ID)
-
-	var total int64
-	if err := query.Count(&total).Error; err != nil {
+	// 查询装配走 queryShopProducts（与 SSR 店铺页共用）；API 不开放 keyword（现状不变）
+	listData, total, err := h.queryShopProducts(shop.ID, page, pageSize, "")
+	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 		return
 	}
 
-	var products []model.Product
-	offset := (page - 1) * pageSize
-	if err := query.Preload("Images").
-		Offset(offset).
-		Limit(pageSize).
-		Order("products.id DESC").
-		Find(&products).Error; err != nil {
-		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
-		return
-	}
-
-	// 取本页商品的在库总量（IN 限定在本页 ≤pageSize 个 id，开销小）
-	qtyMap := make(map[uint64]float64, len(products))
-	if len(products) > 0 {
-		pageIDs := make([]uint64, len(products))
-		for i, p := range products {
-			pageIDs[i] = p.ID
-		}
-		var stockRows []struct {
-			ProductID uint64
-			Qty       float64
-		}
-		h.db.Model(&model.Inventory{}).
-			Select("product_id, SUM(quantity) AS qty").
-			Where("shop_id = ? AND deleted_at IS NULL AND quantity > 0 AND product_id IN ?", shop.ID, pageIDs).
-			Group("product_id").
-			Scan(&stockRows)
-		for _, s := range stockRows {
-			qtyMap[s.ProductID] = s.Qty
-		}
-	}
-
-	listData := make([]publicProductResp, len(products))
-	for i, p := range products {
-		imgs := make([]publicProductImage, len(p.Images))
-		for j, img := range p.Images {
-			imgs[j] = publicProductImage{URL: img.URL}
-		}
-		listData[i] = publicProductResp{
-			ID:        p.ID,
-			PublicID:  p.PublicID,
-			Code:      p.Code,
-			Name:      p.Name,
-			Series:    p.Series,
-			Spec:      p.Spec,
-			Brand:     p.Brand,
-			Unit:      p.Unit,
-			SalePrice: p.SalePrice,
-			Quantity:  qtyMap[p.ID],
-			Images:    imgs,
-		}
-	}
-
 	c.JSON(http.StatusOK, gin.H{
 		"data":      listData,
 		"total":     total,
@@ -314,51 +216,7 @@ func (h *PublicHandler) ListShopProducts(c *gin.Context) {
 	})
 }
 
-// ProductPage GET /product/:public_id
-// 返回注入了基础 Open Graph 标签的 Flutter index.html，供微信/飞书等社交平台爬虫生成分享卡片。
-// 找不到商品时原样返回 index.html，让 Flutter 自行展示"商品不存在"；爬虫拿不到 OG 标签但页面不报错。
-func (h *PublicHandler) ProductPage(c *gin.Context) {
-	publicID := c.Param("public_id")
-
-	// 读取 Flutter 构建产物 index.html
-	idxPath := config.C.Storage.WebDir + "/index.html"
-	idxBytes, err := os.ReadFile(idxPath)
-	if err != nil {
-		c.String(http.StatusInternalServerError, "index.html not found: %s", idxPath)
-		return
-	}
-	idxHTML := string(idxBytes)
-
-	// 查商品（只取 OG 所需字段，轻量查询）
-	var product model.Product
-	if err := h.db.Select("id, public_id, name, brand, series, spec, shop_id").
-		Where("public_id = ? AND deleted_at IS NULL", publicID).
-		Preload("Images").
-		First(&product).Error; err != nil {
-		// 查不到商品：原样返回 index.html，让 Flutter 展示"商品不存在"
-		c.Data(http.StatusOK, "text/html; charset=utf-8", idxBytes)
-		return
-	}
-
-	// 查门店名
-	var shop model.Shop
-	shopName := ""
-	if err := h.db.Select("name").Where("id = ?", product.ShopID).First(&shop).Error; err == nil {
-		shopName = shop.Name
-	}
-
-	// 构造 OG 标签并注入 </head> 前
-	ogTags := buildProductOG(product, shopName, config.C.Storage.PublicURL)
-	ogTitle := buildOGTitle(product)
-	// 同时替换 <title> 标签，微信/飞书等平台有时优先读 <title> 而非 og:title
-	// 用正则替换避免缩进空格导致字符串不匹配
-	titleRe := regexp.MustCompile(`<title>[^<]*</title>`)
-	out := titleRe.ReplaceAllString(idxHTML, "<title>"+html.EscapeString(ogTitle)+"</title>")
-	out = strings.Replace(out, "</head>", ogTags+"</head>", 1)
-	// 禁止缓存，确保爬虫每次都能拿到最新 OG 标签
-	c.Header("Cache-Control", "no-store")
-	c.Data(http.StatusOK, "text/html; charset=utf-8", []byte(out))
-}
+// ProductPage 已 SSR 化，实现移至 public_page.go（2026-07-07 公开页去 Flutter 化）。
 
 // buildOGTitle 生成商品的分享标题：品牌 + 商品名（品牌已含在名字中时不重复）+ 系列。
 func buildOGTitle(product model.Product) string {
@@ -403,8 +261,8 @@ func buildProductOG(product model.Product, shopName, publicURL string) string {
 		siteName = shopName + " · " + siteName
 	}
 
-	// og:url
-	pageURL := publicURL + "/app/product/" + product.PublicID
+	// og:url：指向 SSR 短链（公开页规范入口）
+	pageURL := publicURL + "/product/" + product.PublicID
 
 	var sb strings.Builder
 	sb.WriteString("\n")

backend/internal/handler/public_page.go

@@ -0,0 +1,426 @@
+package handler
+
+import (
+	"bytes"
+	"embed"
+	"fmt"
+	"html"
+	"html/template"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+
+	"github.com/wangjia/jiu/backend/config"
+	"github.com/wangjia/jiu/backend/internal/model"
+)
+
+// 公开页 SSR（2026-07-07 设计 docs/design/public-page-speedup.html）：
+// 商品页 /product/:public_id 与店铺页 /shop/:shop_code 由后端直出轻量 HTML（~20KB），
+// 顾客扫码/分享动线不再加载 Flutter Web（12.5MB 首包在 3Mbps 带宽下约 30s）。
+// 数据装配与公开 API 共用同一函数（loadPublicProduct / queryShopProducts），字段口径零漂移。
+
+//go:embed templates/public_product.html templates/public_shop.html
+var pageTemplates embed.FS
+
+var (
+	productPageTpl = template.Must(template.ParseFS(pageTemplates, "templates/public_product.html"))
+	shopPageTpl    = template.Must(template.ParseFS(pageTemplates, "templates/public_shop.html"))
+)
+
+// publicProductData 公开商品数据装配结果——GetProduct（JSON API）与 ProductPage（SSR）共用。
+type publicProductData struct {
+	Product   model.Product
+	Shop      model.Shop
+	HasShop   bool
+	Batch     *model.Inventory
+	Origin    string
+	ShelfLife string
+	Storage   string
+	DescTitle string
+	DescBody  string
+	Keywords  []string
+}
+
+// loadPublicProduct 按 public_id 装配公开商品数据（公开字段口径的单一实现）。
+func (h *PublicHandler) loadPublicProduct(publicID string) (*publicProductData, error) {
+	var product model.Product
+	if err := h.db.Where("public_id = ? AND deleted_at IS NULL", publicID).
+		Preload("Images").
+		Preload("Origin").
+		Preload("ShelfLife").
+		Preload("Storage").
+		Preload("DescriptionDoc").
+		First(&product).Error; err != nil {
+		return nil, err
+	}
+
+	d := &publicProductData{Product: product, ShelfLife: defaultShelfLife, Storage: defaultStorage}
+
+	if err := h.db.Where("id = ?", product.ShopID).First(&d.Shop).Error; err == nil {
+		d.HasShop = true
+	}
+
+	// 最近一条有量库存作为批次信息
+	var inv model.Inventory
+	if err := h.db.Where("product_id = ? AND quantity > 0 AND deleted_at IS NULL", product.ID).
+		Order("created_at DESC").
+		First(&inv).Error; err == nil {
+		d.Batch = &inv
+	}
+
+	if product.Origin != nil {
+		d.Origin = product.Origin.Name
+	}
+	if product.ShelfLife != nil {
+		d.ShelfLife = product.ShelfLife.Name
+	}
+	if product.Storage != nil {
+		d.Storage = product.Storage.Name
+	}
+	d.DescTitle, d.DescBody, d.Keywords = buildDescription(product)
+	return d, nil
+}
+
+// queryShopProducts 店铺公开商品列表查询——ListShopProducts（JSON API）与 ShopPage（SSR）共用。
+// keyword 为空时不过滤（API 现状）；非空时按 名称/编号/全拼/首字母 模糊匹配（SSR 搜索框）。
+func (h *PublicHandler) queryShopProducts(shopID uint64, page, pageSize int, keyword string) ([]publicProductResp, int64, error) {
+	// 仅列「有库存」的商品：JOIN 库存按 product 聚合（数量>0）的子查询。
+	stockSub := h.db.Model(&model.Inventory{}).
+		Select("product_id, SUM(quantity) AS qty").
+		Where("shop_id = ? AND deleted_at IS NULL AND quantity > 0", shopID).
+		Group("product_id")
+
+	query := h.db.Model(&model.Product{}).
+		Joins("JOIN (?) AS stk ON stk.product_id = products.id", stockSub).
+		Where("products.shop_id = ? AND products.public_id IS NOT NULL AND products.public_id != '' AND products.deleted_at IS NULL", shopID)
+
+	if kw := strings.TrimSpace(keyword); kw != "" {
+		like := "%" + kw + "%"
+		query = query.Where(
+			"products.name LIKE ? OR products.code LIKE ? OR products.name_pinyin LIKE ? OR products.name_initials LIKE ?",
+			like, like, like, like)
+	}
+
+	var total int64
+	if err := query.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+
+	var products []model.Product
+	if err := query.Preload("Images").
+		Offset((page - 1) * pageSize).
+		Limit(pageSize).
+		Order("products.id DESC").
+		Find(&products).Error; err != nil {
+		return nil, 0, err
+	}
+
+	// 取本页商品的在库总量（IN 限定在本页 ≤pageSize 个 id，开销小）
+	qtyMap := make(map[uint64]float64, len(products))
+	if len(products) > 0 {
+		pageIDs := make([]uint64, len(products))
+		for i, p := range products {
+			pageIDs[i] = p.ID
+		}
+		var stockRows []struct {
+			ProductID uint64
+			Qty       float64
+		}
+		h.db.Model(&model.Inventory{}).
+			Select("product_id, SUM(quantity) AS qty").
+			Where("shop_id = ? AND deleted_at IS NULL AND quantity > 0 AND product_id IN ?", shopID, pageIDs).
+			Group("product_id").
+			Scan(&stockRows)
+		for _, s := range stockRows {
+			qtyMap[s.ProductID] = s.Qty
+		}
+	}
+
+	listData := make([]publicProductResp, len(products))
+	for i, p := range products {
+		imgs := make([]publicProductImage, len(p.Images))
+		for j, img := range p.Images {
+			imgs[j] = publicProductImage{URL: img.URL}
+		}
+		listData[i] = publicProductResp{
+			ID:        p.ID,
+			PublicID:  p.PublicID,
+			Code:      p.Code,
+			Name:      p.Name,
+			Series:    p.Series,
+			Spec:      p.Spec,
+			Brand:     p.Brand,
+			Unit:      p.Unit,
+			SalePrice: p.SalePrice,
+			Quantity:  qtyMap[p.ID],
+			Images:    imgs,
+		}
+	}
+	return listData, total, nil
+}
+
+// ── 商品公开页 SSR ──
+
+type productPageVM struct {
+	PageTitle string
+	OGTags    template.HTML
+	Found     bool
+	Name      string
+	Code      string
+	Series    string
+	Spec      string
+	Unit      string
+	Price     string
+	Images    []string
+	Keywords  []string
+	DescTitle string
+	DescBody  string
+	Origin    string
+	ShelfLife string
+	Storage   string
+	HasBatch  bool
+	ProdDate  string
+	BatchNo   string
+	InDate    string
+	HasShop   bool
+	ShopName  string
+	ShopCode  string
+	ShopPhone string
+	ShopAddr  string
+	ShopHours string
+	ShopWx    string
+	AppURL    string
+}
+
+// ProductPage GET /product/:public_id
+// 后端直出轻量商品页（含 OG 标签，微信/飞书分享卡片与人看同一页）。
+// 找不到商品时渲染同风格「商品不存在」页（HTTP 200，对爬虫友好的历史行为保持）。
+func (h *PublicHandler) ProductPage(c *gin.Context) {
+	publicID := c.Param("public_id")
+
+	d, err := h.loadPublicProduct(publicID)
+	if err != nil {
+		renderPage(c, productPageTpl, productPageVM{PageTitle: "商品不存在 · 岩美酒库"})
+		return
+	}
+
+	p := d.Product
+	shopName := ""
+	if d.HasShop {
+		shopName = d.Shop.Name
+	}
+
+	// 页面主标题：品牌前缀（名称未含品牌时）+ 名称；系列走信息行与 chips
+	name := p.Name
+	if p.Brand != "" && !strings.Contains(p.Name, p.Brand) {
+		name = p.Brand + p.Name
+	}
+
+	vm := productPageVM{
+		PageTitle: buildOGTitle(p) + " · " + siteNameFor(shopName),
+		OGTags:    template.HTML(buildProductOG(p, shopName, config.C.Storage.PublicURL)), // #nosec G203 -- buildProductOG 内部对所有值 html.EscapeString
+		Found:     true,
+		Name:      name,
+		Code:      p.Code,
+		Series:    p.Series,
+		Spec:      p.Spec,
+		Unit:      p.Unit,
+		Price:     fmtYuan(p.SalePrice),
+		Keywords:  d.Keywords,
+		DescTitle: d.DescTitle,
+		DescBody:  d.DescBody,
+		Origin:    d.Origin,
+		ShelfLife: d.ShelfLife,
+		Storage:   d.Storage,
+		AppURL:    "/app/product/" + p.PublicID,
+	}
+	for _, img := range p.Images {
+		if img.URL != "" {
+			vm.Images = append(vm.Images, img.URL)
+		}
+	}
+	if d.Batch != nil {
+		vm.HasBatch = true
+		if d.Batch.ProductionDate != nil {
+			vm.ProdDate = d.Batch.ProductionDate.Time.Format("2006-01-02")
+		}
+		vm.BatchNo = d.Batch.BatchNo
+		vm.InDate = d.Batch.CreatedAt.Format("2006-01-02")
+	}
+	if d.HasShop {
+		vm.HasShop = true
+		vm.ShopName = d.Shop.Name
+		vm.ShopCode = d.Shop.Code
+		vm.ShopPhone = d.Shop.Phone
+		vm.ShopAddr = d.Shop.Address
+		vm.ShopHours = d.Shop.BusinessHours
+		vm.ShopWx = d.Shop.WechatID
+	}
+	renderPage(c, productPageTpl, vm)
+}
+
+// ── 店铺公开页 SSR ──
+
+type shopPageItemVM struct {
+	PublicID string
+	Name     string
+	Sub      string
+	Code     string
+	Img      string
+	Price    string
+}
+
+type shopPageVM struct {
+	PageTitle string
+	OGTags    template.HTML
+	Found     bool
+	ShopName  string
+	LogoURL   string
+	Total     int64
+	Q         string
+	Page      int
+	Items     []shopPageItemVM
+	PrevURL   string
+	NextURL   string
+}
+
+// ShopPage GET /shop/:shop_code
+// 店铺公开商品列表直出页：搜索（?q=）+ 分页（?page=），商品卡链接到 /product/:public_id。
+func (h *PublicHandler) ShopPage(c *gin.Context) {
+	shopCode := c.Param("shop_code")
+
+	var shop model.Shop
+	if err := h.db.Where("code = ? AND deleted_at IS NULL", shopCode).First(&shop).Error; err != nil {
+		renderPage(c, shopPageTpl, shopPageVM{PageTitle: "店铺不存在 · 岩美酒库"})
+		return
+	}
+
+	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
+	if page < 1 {
+		page = 1
+	}
+	const pageSize = 20 // 与公开 API 上限一致（反爬口径）
+	q := strings.TrimSpace(c.Query("q"))
+
+	items, total, err := h.queryShopProducts(shop.ID, page, pageSize, q)
+	if err != nil {
+		c.String(http.StatusInternalServerError, "查询失败")
+		return
+	}
+
+	vm := shopPageVM{
+		PageTitle: shop.Name + " · 在售商品 · 岩美酒库",
+		OGTags:    template.HTML(buildShopOG(shop, total, config.C.Storage.PublicURL)), // #nosec G203 -- buildShopOG 内部对所有值 html.EscapeString
+		Found:     true,
+		ShopName:  shop.Name,
+		LogoURL:   shop.LogoURL,
+		Total:     total,
+		Q:         q,
+		Page:      page,
+	}
+	for _, it := range items {
+		sub := make([]string, 0, 2)
+		if it.Series != "" {
+			sub = append(sub, it.Series)
+		}
+		if it.Spec != "" {
+			sub = append(sub, it.Spec)
+		}
+		img := ""
+		if len(it.Images) > 0 {
+			img = it.Images[0].URL
+		}
+		name := it.Name
+		if it.Brand != "" && !strings.Contains(it.Name, it.Brand) {
+			name = it.Brand + it.Name
+		}
+		vm.Items = append(vm.Items, shopPageItemVM{
+			PublicID: it.PublicID,
+			Name:     name,
+			Sub:      strings.Join(sub, " · "),
+			Code:     it.Code,
+			Img:      img,
+			Price:    fmtYuan(it.SalePrice),
+		})
+	}
+	if page > 1 {
+		vm.PrevURL = shopPageURL(q, page-1)
+	}
+	if int64(page*pageSize) < total {
+		vm.NextURL = shopPageURL(q, page+1)
+	}
+	renderPage(c, shopPageTpl, vm)
+}
+
+// buildShopOG 店铺页 OG 标签（值全部转义，同 buildProductOG 约定）。
+func buildShopOG(shop model.Shop, total int64, publicURL string) string {
+	var sb strings.Builder
+	sb.WriteString("\n")
+	sb.WriteString(`  <meta property="og:type" content="website">` + "\n")
+	sb.WriteString(`  <meta property="og:site_name" content="岩美酒库">` + "\n")
+	sb.WriteString(`  <meta property="og:url" content="` + html.EscapeString(publicURL+"/shop/"+shop.Code) + `">` + "\n")
+	sb.WriteString(`  <meta property="og:title" content="` + html.EscapeString(shop.Name) + `">` + "\n")
+	sb.WriteString(`  <meta property="og:description" content="` + html.EscapeString(fmt.Sprintf("在售商品 %d 件 · 正品保障", total)) + `">` + "\n")
+	if shop.LogoURL != "" {
+		sb.WriteString(`  <meta property="og:image" content="` + html.EscapeString(publicURL+shop.LogoURL) + `">` + "\n")
+	}
+	return sb.String()
+}
+
+func shopPageURL(q string, page int) string {
+	v := url.Values{}
+	if q != "" {
+		v.Set("q", q)
+	}
+	if page > 1 {
+		v.Set("page", strconv.Itoa(page))
+	}
+	if enc := v.Encode(); enc != "" {
+		return "?" + enc
+	}
+	return "?"
+}
+
+func siteNameFor(shopName string) string {
+	if shopName != "" {
+		return shopName
+	}
+	return "岩美酒库"
+}
+
+// fmtYuan 价格显示：0 或负数返回空串（模板隐藏该行）；整数不带小数，千分位分组。
+func fmtYuan(v float64) string {
+	if v <= 0 {
+		return ""
+	}
+	s := strconv.FormatFloat(v, 'f', 2, 64)
+	s = strings.TrimSuffix(s, ".00")
+	parts := strings.SplitN(s, ".", 2)
+	digits := parts[0]
+	var b strings.Builder
+	for i, ch := range digits {
+		if i > 0 && (len(digits)-i)%3 == 0 {
+			b.WriteByte(',')
+		}
+		b.WriteRune(ch)
+	}
+	out := "¥" + b.String()
+	if len(parts) > 1 {
+		out += "." + parts[1]
+	}
+	return out
+}
+
+func renderPage(c *gin.Context, tpl *template.Template, vm interface{}) {
+	var buf bytes.Buffer
+	if err := tpl.Execute(&buf, vm); err != nil {
+		c.String(http.StatusInternalServerError, "render error")
+		return
+	}
+	// 内容含库存批次等动态信息，禁缓存（与旧 OG 注入行为一致，爬虫每次拿最新）
+	c.Header("Cache-Control", "no-store")
+	c.Data(http.StatusOK, "text/html; charset=utf-8", buf.Bytes())
+}

backend/internal/handler/public_page_test.go

@@ -0,0 +1,156 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"gorm.io/gorm"
+
+	"github.com/wangjia/jiu/backend/testutil"
+)
+
+// SSR 公开页（2026-07-07 去 Flutter 化）：商品页 /product/:id 与店铺页 /shop/:code
+// 由后端直出轻量 HTML；断言内容、OG 标签、敏感字段零暴露、搜索与分页。
+
+func setupPageRouter(db *gorm.DB) *gin.Engine {
+	h := NewPublicHandler(db)
+	r := gin.New()
+	r.Use(gin.Recovery())
+	r.GET("/product/:public_id", h.ProductPage)
+	r.GET("/shop/:shop_code", h.ShopPage)
+	return r
+}
+
+func getPage(r *gin.Engine, path string) *httptest.ResponseRecorder {
+	req := httptest.NewRequest("GET", path, nil)
+	w := httptest.NewRecorder()
+	r.ServeHTTP(w, req)
+	return w
+}
+
+func TestProductPage_SSR(t *testing.T) {
+	db := testutil.SetupTestDB()
+	shop := testutil.CreateTestShop(db, "PPG01")
+	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
+	r := setupPageRouter(db)
+
+	p := testutil.CreateTestProduct(db, shop.ID, "茅台飞天53度")
+	setPublicID(db, p.ID, "pub-ssr-001")
+	addInventory(db, shop.ID, wh.ID, p.ID, 6)
+
+	w := getPage(r, "/product/pub-ssr-001")
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Header().Get("Content-Type"), "text/html")
+	assert.Equal(t, "no-store", w.Header().Get("Cache-Control"))
+
+	body := w.Body.String()
+	// 轻量页：不再是 Flutter 壳
+	assert.NotContains(t, body, "flutter_bootstrap")
+	assert.NotContains(t, body, `<base href="/app/">`)
+	// 内容
+	assert.Contains(t, body, "茅台飞天53度")
+	assert.Contains(t, body, shop.Name)
+	// OG 标签（og:url 指向 SSR 短链）
+	assert.Contains(t, body, `property="og:title"`)
+	assert.Contains(t, body, "/product/pub-ssr-001")
+	// 门店互跳 + App 兜底链接
+	assert.Contains(t, body, "/shop/"+shop.Code)
+	assert.Contains(t, body, "/app/product/pub-ssr-001")
+	// 敏感字段零暴露（成本/进价永不出现在公开页）
+	for _, s := range []string{"cost", "purchase_price", "profit"} {
+		assert.NotContains(t, body, s, "公开页不得出现敏感字段名 %s", s)
+	}
+}
+
+func TestProductPage_NotFound(t *testing.T) {
+	db := testutil.SetupTestDB()
+	r := setupPageRouter(db)
+
+	w := getPage(r, "/product/no-such-id")
+	// 历史行为保持：HTTP 200 + 友好文案（对爬虫不报错）
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "商品不存在")
+}
+
+func TestShopPage_SSR_SearchAndPaging(t *testing.T) {
+	db := testutil.SetupTestDB()
+	shop := testutil.CreateTestShop(db, "SPG01")
+	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
+	r := setupPageRouter(db)
+
+	// 25 个有库存商品 → 2 页；外加一个名称可搜索的
+	for i := 0; i < 25; i++ {
+		p := testutil.CreateTestProduct(db, shop.ID, "批量酒"+strings.Repeat("x", i%3))
+		setPublicID(db, p.ID, "sp-"+strings.Repeat("a", 1)+string(rune('A'+i%26))+strings.Repeat("b", i/26+1))
+		addInventory(db, shop.ID, wh.ID, p.ID, 3)
+	}
+	target := testutil.CreateTestProduct(db, shop.ID, "五粮液普五")
+	setPublicID(db, target.ID, "sp-target")
+	addInventory(db, shop.ID, wh.ID, target.ID, 2)
+
+	// 第 1 页：20 条 + 下一页链接
+	w := getPage(r, "/shop/"+shop.Code)
+	assert.Equal(t, http.StatusOK, w.Code)
+	body := w.Body.String()
+	assert.Contains(t, body, shop.Name)
+	assert.Contains(t, body, "26 件")
+	assert.Contains(t, body, "page=2")
+	assert.Equal(t, 20, strings.Count(body, `class="item"`), "第一页应有 20 张商品卡")
+	assert.NotContains(t, body, "flutter_bootstrap")
+
+	// 第 2 页：6 条 + 上一页链接
+	w = getPage(r, "/shop/"+shop.Code+"?page=2")
+	body = w.Body.String()
+	assert.Equal(t, 6, strings.Count(body, `class="item"`))
+	assert.Contains(t, body, "上一页")
+
+	// 搜索：只命中目标商品，商品卡链接到 SSR 商品页
+	w = getPage(r, "/shop/"+shop.Code+"?q="+urlQueryEscape("五粮液"))
+	body = w.Body.String()
+	assert.Equal(t, 1, strings.Count(body, `class="item"`))
+	assert.Contains(t, body, "/product/sp-target")
+
+	// 搜索无结果：空态文案
+	w = getPage(r, "/shop/"+shop.Code+"?q=NOPE")
+	assert.Contains(t, w.Body.String(), "没有找到")
+}
+
+func TestShopPage_NotFound(t *testing.T) {
+	db := testutil.SetupTestDB()
+	r := setupPageRouter(db)
+	w := getPage(r, "/shop/NOSHOP")
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "店铺不存在")
+}
+
+// API 与 SSR 共用装配后的回归：ListShopProducts 行为不变（不受 keyword 影响）
+func TestListShopProducts_UnaffectedByRefactor(t *testing.T) {
+	db := testutil.SetupTestDB()
+	shop := testutil.CreateTestShop(db, "SPG02")
+	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
+	p := testutil.CreateTestProduct(db, shop.ID, "剑南春")
+	setPublicID(db, p.ID, "sp2-x")
+	addInventory(db, shop.ID, wh.ID, p.ID, 1)
+	r := setupPublicRouter(db)
+
+	w := getPage(r, "/api/v1/public/shops/"+shop.Code+"/products")
+	assert.Equal(t, http.StatusOK, w.Code)
+	resp := parseResponse(w)
+	assert.Equal(t, float64(1), resp["total"].(float64))
+}
+
+func urlQueryEscape(s string) string {
+	// 测试用最小转义（仅中文场景）
+	var b strings.Builder
+	for _, c := range []byte(s) {
+		b.WriteString("%")
+		const hex = "0123456789ABCDEF"
+		b.WriteByte(hex[c>>4])
+		b.WriteByte(hex[c&0xF])
+	}
+	return b.String()
+}

backend/internal/handler/templates/public_product.html

@@ -0,0 +1,101 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>{{.PageTitle}}</title>{{.OGTags}}
+<style>
+  :root{--primary:#2563AC;--primary-dark:#154072;--ink:#232934;--muted:#6E7888;
+        --border:#DCE2EB;--paper:#F5F7FA;--head:#F0F4FF;--ok:#2E8B57;--ok-bg:#E6F3EC;}
+  *{box-sizing:border-box;margin:0;font-family:-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;}
+  body{background:var(--paper);color:var(--ink);line-height:1.65;font-size:15px;}
+  .wrap{max-width:640px;margin:0 auto;padding:14px 14px 40px;}
+  .card{background:#fff;border:1px solid var(--border);border-radius:12px;padding:16px;margin-bottom:12px;}
+  .gallery{display:flex;gap:8px;overflow-x:auto;scroll-snap-type:x mandatory;-webkit-overflow-scrolling:touch;border-radius:12px;margin-bottom:12px;}
+  .gallery img{width:100%;max-width:640px;flex:0 0 100%;scroll-snap-align:center;border-radius:12px;object-fit:cover;background:#fff;border:1px solid var(--border);}
+  h1{font-size:20px;line-height:1.4;margin-bottom:6px;}
+  .chips{display:flex;flex-wrap:wrap;gap:6px;margin:8px 0 2px;}
+  .chip{font-size:12px;padding:2px 10px;border-radius:10px;background:var(--head);color:var(--primary-dark);}
+  .price{font-size:22px;font-weight:700;color:var(--primary);margin-top:6px;}
+  .price small{font-size:12px;font-weight:400;color:var(--muted);}
+  .row{display:flex;justify-content:space-between;gap:12px;padding:9px 0;border-bottom:1px solid #EEF1F5;font-size:14px;}
+  .row:last-child{border-bottom:none;}
+  .row span{color:var(--muted);flex:none;}
+  .row b{font-weight:600;text-align:right;word-break:break-all;}
+  .sec-t{font-size:13px;font-weight:600;color:var(--primary-dark);margin-bottom:8px;}
+  .desc{font-size:14px;color:var(--ink);white-space:pre-wrap;}
+  .verify{display:flex;align-items:center;gap:8px;background:var(--ok-bg);color:var(--ok);border-radius:10px;padding:10px 14px;font-size:13px;font-weight:600;margin-bottom:12px;}
+  a{color:var(--primary);text-decoration:none;}
+  .shop-name{font-size:16px;font-weight:700;}
+  .foot{text-align:center;color:var(--muted);font-size:12px;margin-top:18px;}
+  .foot a{color:var(--muted);text-decoration:underline;}
+  .empty{text-align:center;padding:60px 20px;color:var(--muted);}
+  .empty h1{font-size:18px;color:var(--ink);margin-bottom:8px;}
+</style>
+</head>
+<body>
+<div class="wrap">
+{{if .Found}}
+  {{if .Images}}
+  <div class="gallery">
+    {{range $i, $img := .Images}}
+    <img src="{{$img}}" alt="{{$.Name}}" decoding="async"{{if $i}} loading="lazy"{{end}}>
+    {{end}}
+  </div>
+  {{end}}
+
+  <div class="card">
+    <h1>{{.Name}}</h1>
+    {{if .Keywords}}<div class="chips">{{range .Keywords}}<span class="chip">{{.}}</span>{{end}}</div>{{end}}
+    {{if .Price}}<div class="price">{{.Price}}{{if .Unit}} <small>/ {{.Unit}}</small>{{end}}</div>{{end}}
+  </div>
+
+  <div class="verify">✓ 正品保障 · 扫码验真 · 官方渠道供应</div>
+
+  <div class="card">
+    <div class="sec-t">商品信息</div>
+    {{if .Code}}<div class="row"><span>商品编号</span><b>{{.Code}}</b></div>{{end}}
+    {{if .Series}}<div class="row"><span>系列</span><b>{{.Series}}</b></div>{{end}}
+    {{if .Spec}}<div class="row"><span>规格</span><b>{{.Spec}}</b></div>{{end}}
+    {{if .Origin}}<div class="row"><span>产地</span><b>{{.Origin}}</b></div>{{end}}
+    <div class="row"><span>保质期</span><b>{{.ShelfLife}}</b></div>
+    <div class="row"><span>储存方式</span><b>{{.Storage}}</b></div>
+  </div>
+
+  {{if .HasBatch}}
+  <div class="card">
+    <div class="sec-t">批次信息</div>
+    {{if .ProdDate}}<div class="row"><span>生产日期</span><b>{{.ProdDate}}</b></div>{{end}}
+    {{if .BatchNo}}<div class="row"><span>批次号</span><b>{{.BatchNo}}</b></div>{{end}}
+    {{if .InDate}}<div class="row"><span>入库日期</span><b>{{.InDate}}</b></div>{{end}}
+  </div>
+  {{end}}
+
+  {{if .DescBody}}
+  <div class="card">
+    <div class="sec-t">{{.DescTitle}}</div>
+    <div class="desc">{{.DescBody}}</div>
+  </div>
+  {{end}}
+
+  {{if .HasShop}}
+  <div class="card">
+    <div class="sec-t">门店信息</div>
+    <div class="row"><span>门店</span><b>{{if .ShopCode}}<a class="shop-name" href="/shop/{{.ShopCode}}">{{.ShopName}} ›</a>{{else}}{{.ShopName}}{{end}}</b></div>
+    {{if .ShopPhone}}<div class="row"><span>电话</span><b><a href="tel:{{.ShopPhone}}">{{.ShopPhone}}</a></b></div>{{end}}
+    {{if .ShopAddr}}<div class="row"><span>地址</span><b>{{.ShopAddr}}</b></div>{{end}}
+    {{if .ShopHours}}<div class="row"><span>营业时间</span><b>{{.ShopHours}}</b></div>{{end}}
+    {{if .ShopWx}}<div class="row"><span>微信</span><b>{{.ShopWx}}</b></div>{{end}}
+    {{if .ShopCode}}<div class="row"><span></span><b><a href="/shop/{{.ShopCode}}">查看本店更多商品 ›</a></b></div>{{end}}
+  </div>
+  {{end}}
+{{else}}
+  <div class="card empty">
+    <h1>商品不存在或已下架</h1>
+    <p>请确认链接来源，或联系门店核实。</p>
+  </div>
+{{end}}
+  <div class="foot">岩美酒库 · 正品溯源{{if .AppURL}} · <a href="{{.AppURL}}">在 App 中查看</a>{{end}}</div>
+</div>
+</body>
+</html>

backend/internal/handler/templates/public_shop.html

@@ -0,0 +1,87 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>{{.PageTitle}}</title>{{.OGTags}}
+<style>
+  :root{--primary:#2563AC;--primary-dark:#154072;--ink:#232934;--muted:#6E7888;
+        --border:#DCE2EB;--paper:#F5F7FA;--head:#F0F4FF;}
+  *{box-sizing:border-box;margin:0;font-family:-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;}
+  body{background:var(--paper);color:var(--ink);line-height:1.6;font-size:15px;}
+  .wrap{max-width:640px;margin:0 auto;padding:14px 14px 40px;}
+  .head{display:flex;align-items:center;gap:12px;padding:6px 2px 14px;}
+  .head img{width:44px;height:44px;border-radius:10px;object-fit:cover;border:1px solid var(--border);background:#fff;}
+  .head h1{font-size:18px;line-height:1.3;}
+  .head .sub{font-size:12px;color:var(--muted);}
+  form{display:flex;gap:8px;margin-bottom:12px;}
+  input[type=search]{flex:1;border:1px solid var(--border);border-radius:10px;padding:9px 12px;font-size:14px;background:#fff;outline:none;}
+  input[type=search]:focus{border-color:var(--primary);}
+  button{border:none;background:var(--primary);color:#fff;border-radius:10px;padding:0 18px;font-size:14px;}
+  .item{display:flex;gap:12px;background:#fff;border:1px solid var(--border);border-radius:12px;padding:12px;margin-bottom:10px;color:var(--ink);}
+  .item img{width:64px;height:64px;border-radius:8px;object-fit:cover;border:1px solid var(--border);flex:none;background:var(--paper);}
+  .item .ph{width:64px;height:64px;border-radius:8px;border:1px solid var(--border);flex:none;background:var(--head);display:flex;align-items:center;justify-content:center;color:var(--muted);font-size:11px;}
+  .item .m{flex:1;min-width:0;}
+  .item .nm{font-weight:600;font-size:15px;line-height:1.4;}
+  .item .sb{font-size:12.5px;color:var(--muted);margin-top:2px;}
+  .item .cd{font-size:12px;color:var(--muted);font-family:ui-monospace,Menlo,monospace;margin-top:2px;}
+  .item .pr{font-size:15px;font-weight:700;color:var(--primary);flex:none;align-self:center;}
+  a{text-decoration:none;color:inherit;}
+  .pager{display:flex;justify-content:space-between;align-items:center;margin-top:16px;font-size:14px;}
+  .pager a{color:var(--primary);font-weight:600;padding:8px 4px;}
+  .pager .off{color:var(--border);}
+  .pager .pg{color:var(--muted);font-size:12.5px;}
+  .empty{text-align:center;padding:60px 20px;color:var(--muted);background:#fff;border:1px solid var(--border);border-radius:12px;}
+  .empty h2{font-size:16px;color:var(--ink);margin-bottom:6px;}
+  .foot{text-align:center;color:var(--muted);font-size:12px;margin-top:18px;}
+</style>
+</head>
+<body>
+<div class="wrap">
+{{if .Found}}
+  <div class="head">
+    {{if .LogoURL}}<img src="{{.LogoURL}}" alt="{{.ShopName}}" decoding="async">{{end}}
+    <div>
+      <h1>{{.ShopName}}</h1>
+      <div class="sub">在售商品 {{.Total}} 件 · 正品保障</div>
+    </div>
+  </div>
+
+  <form method="get" action="">
+    <input type="search" name="q" value="{{.Q}}" placeholder="搜索本店商品（名称 / 编号 / 拼音）">
+    <button type="submit">搜索</button>
+  </form>
+
+  {{if .Items}}
+    {{range .Items}}
+    <a class="item" href="/product/{{.PublicID}}">
+      {{if .Img}}<img src="{{.Img}}" alt="{{.Name}}" loading="lazy" decoding="async">{{else}}<span class="ph">暂无图</span>{{end}}
+      <span class="m">
+        <span class="nm">{{.Name}}</span>
+        {{if .Sub}}<span class="sb" style="display:block">{{.Sub}}</span>{{end}}
+        {{if .Code}}<span class="cd" style="display:block">{{.Code}}</span>{{end}}
+      </span>
+      {{if .Price}}<span class="pr">{{.Price}}</span>{{end}}
+    </a>
+    {{end}}
+    <div class="pager">
+      {{if .PrevURL}}<a href="{{.PrevURL}}">‹ 上一页</a>{{else}}<span class="off">‹ 上一页</span>{{end}}
+      <span class="pg">第 {{.Page}} 页 · 共 {{.Total}} 件</span>
+      {{if .NextURL}}<a href="{{.NextURL}}">下一页 ›</a>{{else}}<span class="off">下一页 ›</span>{{end}}
+    </div>
+  {{else}}
+    <div class="empty">
+      <h2>{{if .Q}}没有找到「{{.Q}}」相关商品{{else}}本店暂无在售商品{{end}}</h2>
+      {{if .Q}}<p>换个关键词试试，或清空搜索查看全部。</p>{{end}}
+    </div>
+  {{end}}
+{{else}}
+  <div class="empty">
+    <h2>店铺不存在</h2>
+    <p>请确认链接来源。</p>
+  </div>
+{{end}}
+  <div class="foot">岩美酒库 · 正品溯源</div>
+</div>
+</body>
+</html>

backend/internal/router/router.go

@@ -65,6 +65,8 @@ func Setup(r *gin.Engine, db *gorm.DB) {
 
 	// 公开商品详情页（注入 OG 标签的 Flutter index.html，供社交分享爬虫读取）
 	r.GET("/product/:public_id", publicReadIP, dqProduct, publicH.ProductPage)
+	// 店铺公开页 SSR（挂与 shops API 同一套闸：分钟限流 + 日配额）
+	r.GET("/shop/:shop_code", shopListIP, dqShopList, publicH.ShopPage)
 
 	v1 := r.Group("/api/v1")