fix: decode URL-encoded filename from contentDisposition header (#1099)

internal/protocol/http/fetcher.go

@@ -23,6 +23,7 @@ import (
 	"github.com/GopeedLab/gopeed/internal/fetcher"
 	"github.com/GopeedLab/gopeed/pkg/base"
 	fhttp "github.com/GopeedLab/gopeed/pkg/protocol/http"
+	"github.com/GopeedLab/gopeed/pkg/util"
 	"github.com/xiaoqidun/setft"
 	"golang.org/x/sync/errgroup"
 )
@@ -172,13 +173,13 @@ func (f *Fetcher) Resolve(req *base.Request) error {
 				filename = strings.Replace(filename, "UTF8", "UTF-8", 1)
 				file.Name, _ = decoder.Decode(filename)
 			} else {
-				file.Name = filename
+				file.Name = util.TryUrlQueryUnescape(filename)
 			}
 		} else {
 			substr := "attachment; filename="
 			index := strings.Index(contentDisposition, substr)
 			if index != -1 {
-				file.Name = contentDisposition[index+len(substr):]
+				file.Name = util.TryUrlQueryUnescape(contentDisposition[index+len(substr):])
 			}
 		}
 	}

pkg/util/url.go

@@ -56,3 +56,13 @@ func ProxyUrlToHandler(proxyUrl *url.URL) func(*http.Request) (*url.URL, error)
 	}
 	return http.ProxyURL(proxyUrl)
 }
+
+// TryUrlQueryUnescape tries to unescape a URL-encoded string.
+//
+// If unescaping fails, it returns the original string.
+func TryUrlQueryUnescape(s string) string {
+	if decoded, err := url.QueryUnescape(s); err == nil {
+		return decoded
+	}
+	return s
+}

pkg/util/url_test.go

@@ -128,3 +128,24 @@ func TestParseDataUri(t *testing.T) {
 		})
 	}
 }
+
+func TestTryURLDecode(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"normal.txt", "normal.txt"},
+		{"%E7%8F%80%E5%B0%94%E8%AF%BA.zip", "珀尔诺.zip"},
+		{"hello%20world.txt", "hello world.txt"},
+		{"bad%2-text", "bad%2-text"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			got := TryUrlQueryUnescape(tt.input)
+			if got != tt.expected {
+				t.Errorf("TryUrlQueryUnescape(%q) = %q, want %q", tt.input, got, tt.expected)
+			}
+		})
+	}
+}