refactor(router): merge frontend.go and frontend_embedded.go into one file

- Declared package-level `registerFrontend` variable in `router.go` as a no-op fallback
- Configured `frontend.go` under `embed_frontend` build tag to override `registerFrontend` on package initialization
- Removed separate `frontend_embedded.go`
- Resolved related revive linter warnings

internal/router/custom.go

@@ -1,6 +1,7 @@
 // Copyright 2026 Arctel.net
 // SPDX-License-Identifier: Apache-2.0
 
+// Package router 提供 HTTP 路由注册与服务启动
 package router
 
 import (

internal/router/frontend.go

@@ -1,14 +1,111 @@
-//go:build !embed_frontend
+//go:build embed_frontend
 
-// Copyright 2025 linux.do
 // Copyright 2026 Arctel.net
 // SPDX-License-Identifier: Apache-2.0
 
-// Package router 提供 HTTP 路由注册与服务启动
 package router
 
-import "github.com/gin-gonic/gin"
+import (
+	"embed"
+	"io"
+	"io/fs"
+	"net/http"
+	"strings"
 
-func registerFrontend(_ *gin.Engine) {
+	"github.com/gin-gonic/gin"
-	// No-op when not embedding frontend
+)
+
+//go:embed all:dist
+var frontendFS embed.FS
+
+func serveFileDirect(c *gin.Context, subFS fs.FS, filePath string) bool {
+	file, err := subFS.Open(filePath)
+	if err != nil {
+		return false
+	}
+	defer file.Close()
+
+	stat, err := file.Stat()
+	if err != nil {
+		return false
+	}
+
+	if stat.IsDir() {
+		return false
+	}
+
+	seeker, ok := file.(io.ReadSeeker)
+	if !ok {
+		return false
+	}
+
+	// 使用 http.ServeContent 直接输出文件内容，不进行路径规范化重定向
+	http.ServeContent(c.Writer, c.Request, filePath, stat.ModTime(), seeker)
+	return true
 }
+
+func init() {
+	registerFrontend = func(r *gin.Engine) {
+		subFS, err := fs.Sub(frontendFS, "dist")
+		if err != nil {
+			panic(err)
+		}
+
+		r.NoRoute(func(c *gin.Context) {
+			path := c.Request.URL.Path
+
+			// API 接口路由或文件服务路由 -> 直接返回，由 Gin 处理标准 404
+			if strings.HasPrefix(path, "/api/") || strings.HasPrefix(path, "/f/") {
+				return
+			}
+
+			// 只处理 GET 和 HEAD 请求
+			if c.Request.Method != http.MethodGet && c.Request.Method != http.MethodHead {
+				c.JSON(http.StatusMethodNotAllowed, gin.H{"error_msg": "Method not allowed"})
+				return
+			}
+
+			// 移除开头的斜杠以在嵌入文件系统中查找
+			cleanPath := strings.TrimPrefix(path, "/")
+
+			// 1. 根路径 -> 直接输出 index.html
+			if cleanPath == "" {
+				if serveFileDirect(c, subFS, "index.html") {
+					return
+				}
+			}
+
+			// 2. 精确匹配（如果对应的文件存在，直接输出）
+			if serveFileDirect(c, subFS, cleanPath) {
+				return
+			}
+
+			// 如果是个目录（例如请求了 "/login"，同时 dist 目录下存在一个叫 "login" 的文件夹目录），
+			// 则查找是否有对应的 ".html" 文件（例如 "login.html"）并进行输出。
+			if cleanPath != "" {
+				htmlPath := cleanPath + ".html"
+				if serveFileDirect(c, subFS, htmlPath) {
+					return
+				}
+			}
+
+			// 3. Next.js Clean URLs 兜底逻辑（例如访问 /settings/security -> 实际映射输出 settings/security.html）
+			if !strings.Contains(cleanPath, ".") {
+				htmlPath := cleanPath + ".html"
+				if serveFileDirect(c, subFS, htmlPath) {
+					return
+				}
+				indexPath := cleanPath + "/index.html"
+				if serveFileDirect(c, subFS, indexPath) {
+					return
+				}
+			}
+
+			// 4. 单页应用（SPA）前端路由兜底：返回 index.html
+			if serveFileDirect(c, subFS, "index.html") {
+				return
+			}
+		})
+	}
+}
+

internal/router/frontend_embedded.go

@@ -1,108 +0,0 @@
-//go:build embed_frontend
-
-// Copyright 2026 Arctel.net
-// SPDX-License-Identifier: Apache-2.0
-
-package router
-
-import (
-	"embed"
-	"io"
-	"io/fs"
-	"net/http"
-	"strings"
-
-	"github.com/gin-gonic/gin"
-)
-
-//go:embed all:dist
-var frontendFS embed.FS
-
-func serveFileDirect(c *gin.Context, subFS fs.FS, filePath string) bool {
-	file, err := subFS.Open(filePath)
-	if err != nil {
-		return false
-	}
-	defer file.Close()
-
-	stat, err := file.Stat()
-	if err != nil {
-		return false
-	}
-
-	if stat.IsDir() {
-		return false
-	}
-
-	seeker, ok := file.(io.ReadSeeker)
-	if !ok {
-		return false
-	}
-
-	// 使用 http.ServeContent 直接输出文件内容，不进行路径规范化重定向
-	http.ServeContent(c.Writer, c.Request, filePath, stat.ModTime(), seeker)
-	return true
-}
-
-func registerFrontend(r *gin.Engine) {
-	subFS, err := fs.Sub(frontendFS, "dist")
-	if err != nil {
-		panic(err)
-	}
-
-	r.NoRoute(func(c *gin.Context) {
-		path := c.Request.URL.Path
-
-		// API 接口路由或文件服务路由 -> 直接返回，由 Gin 处理标准 404
-		if strings.HasPrefix(path, "/api/") || strings.HasPrefix(path, "/f/") {
-			return
-		}
-
-		// 只处理 GET 和 HEAD 请求
-		if c.Request.Method != http.MethodGet && c.Request.Method != http.MethodHead {
-			c.JSON(http.StatusMethodNotAllowed, gin.H{"error_msg": "Method not allowed"})
-			return
-		}
-
-		// 移除开头的斜杠以在嵌入文件系统中查找
-		cleanPath := strings.TrimPrefix(path, "/")
-
-		// 1. 根路径 -> 直接输出 index.html
-		if cleanPath == "" {
-			if serveFileDirect(c, subFS, "index.html") {
-				return
-			}
-		}
-
-		// 2. 精确匹配（如果对应的文件存在，直接输出）
-		if serveFileDirect(c, subFS, cleanPath) {
-			return
-		}
-
-		// 如果是个目录（例如请求了 "/login"，同时 dist 目录下存在一个叫 "login" 的文件夹目录），
-		// 则查找是否有对应的 ".html" 文件（例如 "login.html"）并进行输出。
-		if cleanPath != "" {
-			htmlPath := cleanPath + ".html"
-			if serveFileDirect(c, subFS, htmlPath) {
-				return
-			}
-		}
-
-		// 3. Next.js Clean URLs 兜底逻辑（例如访问 /settings/security -> 实际映射输出 settings/security.html）
-		if !strings.Contains(cleanPath, ".") {
-			htmlPath := cleanPath + ".html"
-			if serveFileDirect(c, subFS, htmlPath) {
-				return
-			}
-			indexPath := cleanPath + "/index.html"
-			if serveFileDirect(c, subFS, indexPath) {
-				return
-			}
-		}
-
-		// 4. 单页应用（SPA）前端路由兜底：返回 index.html
-		if serveFileDirect(c, subFS, "index.html") {
-			return
-		}
-	})
-}

internal/router/router.go

@@ -387,3 +387,7 @@ func registerAdminUploadRoutes(adminRouter *gin.RouterGroup) {
 		adminUploadsRouter.GET("/types", upload.GetDistinctUploadTypes)
 	}
 }
+
+var registerFrontend = func(_ *gin.Engine) {
+	// No-op when not embedding frontend
+}