From 1250647dc3ba07b274501e5d84d7f04dc8095f35 Mon Sep 17 00:00:00 2001
From: Deluan <deluan@navidrome.org>
Date: Mon, 10 Nov 2025 19:47:20 -0500
Subject: [PATCH] refactor(folder): enhance external scanner to support
 target-specific scanning

Signed-off-by: Deluan <deluan@navidrome.org>
---
 core/maintenance_test.go |  4 +-
 scanner/external.go      | 81 +++++++++++++++-------------------------
 2 files changed, 33 insertions(+), 52 deletions(-)

diff --git a/core/maintenance_test.go b/core/maintenance_test.go
index 8e8796ffa..e83d1f8bd 100644
--- a/core/maintenance_test.go
+++ b/core/maintenance_test.go
@@ -373,10 +373,10 @@ type extendedDataStore struct {
 	gcError  error
 }
 
-func (ds *extendedDataStore) GC(ctx context.Context) error {
+func (ds *extendedDataStore) GC(ctx context.Context, libraryIDs ...int) error {
 	ds.gcCalled = true
 	if ds.gcError != nil {
 		return ds.gcError
 	}
-	return ds.MockDataStore.GC(ctx)
+	return ds.MockDataStore.GC(ctx, libraryIDs...)
 }
diff --git a/scanner/external.go b/scanner/external.go
index 86d171346..869034cc2 100644
--- a/scanner/external.go
+++ b/scanner/external.go
@@ -12,7 +12,6 @@ import (
 
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/log"
-	. "github.com/navidrome/navidrome/utils/gg"
 )
 
 // scannerExternal is a scanner that runs an external process to do the scanning. It is used to avoid
@@ -25,68 +24,50 @@ import (
 type scannerExternal struct{}
 
 func (s *scannerExternal) scanAll(ctx context.Context, fullScan bool, progress chan<- *ProgressInfo) {
-	exe, err := os.Executable()
-	if err != nil {
-		progress <- &ProgressInfo{Error: fmt.Sprintf("failed to get executable path: %s", err)}
-		return
-	}
-	log.Debug(ctx, "Spawning external scanner process", "fullScan", fullScan, "path", exe)
-	cmd := exec.CommandContext(ctx, exe, "scan",
-		"--nobanner", "--subprocess",
-		"--configfile", conf.Server.ConfigFile,
-		"--datafolder", conf.Server.DataFolder,
-		"--cachefolder", conf.Server.CacheFolder,
-		If(fullScan, "--full", ""))
-
-	in, out := io.Pipe()
-	defer in.Close()
-	defer out.Close()
-	cmd.Stdout = out
-	cmd.Stderr = os.Stderr
-
-	if err := cmd.Start(); err != nil {
-		progress <- &ProgressInfo{Error: fmt.Sprintf("failed to start scanner process: %s", err)}
-		return
-	}
-	go s.wait(cmd, out)
-
-	decoder := gob.NewDecoder(in)
-	for {
-		var p ProgressInfo
-		if err := decoder.Decode(&p); err != nil {
-			if !errors.Is(err, io.EOF) {
-				progress <- &ProgressInfo{Error: fmt.Sprintf("failed to read status from scanner: %s", err)}
-			}
-			break
-		}
-		progress <- &p
-	}
+	s.scan(ctx, fullScan, nil, progress)
 }
 
 func (s *scannerExternal) scanFolders(ctx context.Context, fullScan bool, targets []ScanTarget, progress chan<- *ProgressInfo) {
+	s.scan(ctx, fullScan, targets, progress)
+}
+
+func (s *scannerExternal) scan(ctx context.Context, fullScan bool, targets []ScanTarget, progress chan<- *ProgressInfo) {
 	exe, err := os.Executable()
 	if err != nil {
 		progress <- &ProgressInfo{Error: fmt.Sprintf("failed to get executable path: %s", err)}
 		return
 	}
 
-	// Build targets string for CLI
-	var targetsStr string
-	for i, target := range targets {
-		if i > 0 {
-			targetsStr += ","
-		}
-		targetsStr += strconv.Itoa(target.LibraryID) + ":" + target.FolderPath
-	}
-
-	log.Debug(ctx, "Spawning external scanner process with targets", "fullScan", fullScan, "path", exe, "targets", targetsStr)
-	cmd := exec.CommandContext(ctx, exe, "scan",
+	// Build command arguments
+	args := []string{
+		"scan",
 		"--nobanner", "--subprocess",
 		"--configfile", conf.Server.ConfigFile,
 		"--datafolder", conf.Server.DataFolder,
 		"--cachefolder", conf.Server.CacheFolder,
-		"--targets", targetsStr,
-		If(fullScan, "--full", ""))
+	}
+
+	// Add targets if provided
+	if len(targets) > 0 {
+		var targetsStr string
+		for i, target := range targets {
+			if i > 0 {
+				targetsStr += ","
+			}
+			targetsStr += strconv.Itoa(target.LibraryID) + ":" + target.FolderPath
+		}
+		args = append(args, "--targets", targetsStr)
+		log.Debug(ctx, "Spawning external scanner process with targets", "fullScan", fullScan, "path", exe, "targets", targetsStr)
+	} else {
+		log.Debug(ctx, "Spawning external scanner process", "fullScan", fullScan, "path", exe)
+	}
+
+	// Add full scan flag if needed
+	if fullScan {
+		args = append(args, "--full")
+	}
+
+	cmd := exec.CommandContext(ctx, exe, args...)
 
 	in, out := io.Pipe()
 	defer in.Close()