Infer file mime type

.gitignore

@@ -0,0 +1 @@
+forgejo-pages

lib/web.go

@@ -12,6 +12,8 @@ import (
 	"net/http"
 	"net/url"
 	"strings"
+	"mime"
+	"path/filepath"
 )
 
 type Forgejo struct {
@@ -34,7 +36,7 @@ func (f *Forgejo) GetFile(ctx context.Context, headers map[string]string, user,
 	if err != nil {
 		return
 	}
-
+	
 	for k, v := range headers {
 		if v == "" {
 			continue
@@ -50,7 +52,7 @@ func (f *Forgejo) GetFile(ctx context.Context, headers map[string]string, user,
 		err = ErrNotFound
 		return
 	}
-
+	
 	return resp, nil
 }
 
@@ -102,7 +104,7 @@ func (f *Forgejo) handle(w http.ResponseWriter, r *http.Request) {
 		}
 		file = strings.Join(arr[2:], "/")
 	}
-
+	
 	headers := map[string]string{}
 	headers["If-None-Match"] = r.Header.Get("If-None-Match")
 	headers["If-Modified-Since"] = r.Header.Get("If-Modified-Since")
@@ -124,12 +126,21 @@ func (f *Forgejo) handle(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer resp.Body.Close()
-
+	
 	trySet(w.Header(), "Etag", resp.Header)
 	trySet(w.Header(), "Last-Modified", resp.Header)
 	trySet(w.Header(), "Content-Length", resp.Header)
 	trySet(w.Header(), "Content-Range", resp.Header)
-
+	contentType := resp.Header.Get("Content-Type")
+	if contentType == "" || strings.HasPrefix(contentType, "text/plain") {
+		if ct := mime.TypeByExtension(filepath.Ext(file)); ct != "" {
+			contentType = ct
+		}
+	}
+	if contentType != "" {
+		w.Header().Set("Content-Type", contentType)
+	}
+	
 	w.WriteHeader(resp.StatusCode)
 	io.Copy(w, resp.Body)
 }