support multiple roots per library

internal/database/schema_migration.go

@@ -1,6 +1,9 @@
 package database
 
 import (
+	"path/filepath"
+	"strings"
+
 	"gorm.io/gorm"
 
 	"github.com/ShukeBta/MediaStationGo/internal/model"
@@ -20,6 +23,9 @@ func AutoMigrate(db *gorm.DB) error {
 	if err := ensurePerformanceIndexes(db); err != nil {
 		return err
 	}
+	if err := ensureLibraryRootsCompatibility(db); err != nil {
+		return err
+	}
 	if isSQLite(db) {
 		return ensureMediaSearchIndex(db)
 	}
@@ -52,6 +58,7 @@ func ensurePerformanceIndexes(db *gorm.DB) error {
 	statements := []string{
 		`CREATE INDEX IF NOT EXISTS idx_media_library_created_active ON media(library_id, created_at DESC) WHERE deleted_at IS NULL`,
 		`CREATE INDEX IF NOT EXISTS idx_media_library_episode_active ON media(library_id, season_num, episode_num, created_at DESC) WHERE deleted_at IS NULL`,
+		`CREATE INDEX IF NOT EXISTS idx_media_library_root_active ON media(library_id, library_root_id) WHERE deleted_at IS NULL`,
 		`CREATE INDEX IF NOT EXISTS idx_media_series_active ON media(series_id, season_num, episode_num) WHERE deleted_at IS NULL`,
 		`CREATE INDEX IF NOT EXISTS idx_favorites_user_media_active ON favorites(user_id, media_id) WHERE deleted_at IS NULL`,
 		`CREATE INDEX IF NOT EXISTS idx_playback_histories_user_media_active ON playback_histories(user_id, media_id, watched_at DESC) WHERE deleted_at IS NULL`,
@@ -77,6 +84,107 @@ func ensurePerformanceIndexes(db *gorm.DB) error {
 	return nil
 }
 
+func ensureLibraryRootsCompatibility(db *gorm.DB) error {
+	var libraries []model.Library
+	if err := db.Find(&libraries).Error; err != nil {
+		return err
+	}
+	for _, lib := range libraries {
+		if strings.TrimSpace(lib.Path) == "" {
+			continue
+		}
+		var count int64
+		if err := db.Model(&model.LibraryRoot{}).Where("library_id = ?", lib.ID).Count(&count).Error; err != nil {
+			return err
+		}
+		if count > 0 {
+			continue
+		}
+		root := model.LibraryRoot{
+			LibraryID: lib.ID,
+			Name:      firstLibraryRootLabel(lib.Path),
+			Path:      lib.Path,
+			Enabled:   lib.Enabled,
+			SortOrder: 0,
+		}
+		if err := db.Create(&root).Error; err != nil {
+			return err
+		}
+		if err := backfillLibraryRootMedia(db, lib, root); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func backfillLibraryRootMedia(db *gorm.DB, lib model.Library, root model.LibraryRoot) error {
+	var rows []model.Media
+	if err := db.Unscoped().
+		Model(&model.Media{}).
+		Select("id", "path").
+		Where("library_id = ? AND (library_root_id = '' OR library_root_id IS NULL)", lib.ID).
+		Find(&rows).Error; err != nil {
+		return err
+	}
+	rootPath := strings.TrimSpace(root.Path)
+	for _, row := range rows {
+		rel, ok := relativePathWithinRoot(row.Path, rootPath)
+		if !ok {
+			continue
+		}
+		if err := db.Unscoped().Model(&model.Media{}).Where("id = ?", row.ID).Updates(map[string]any{
+			"library_root_id": root.ID,
+			"relative_path":   rel,
+		}).Error; err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func relativePathWithinRoot(pathValue, root string) (string, bool) {
+	pathValue = strings.TrimSpace(pathValue)
+	root = strings.TrimSpace(root)
+	if pathValue == "" || root == "" {
+		return "", false
+	}
+	if strings.HasPrefix(strings.ToLower(root), "cloud://") || strings.HasPrefix(strings.ToLower(pathValue), "cloud://") {
+		prefix := strings.TrimRight(root, "/") + "/"
+		if strings.EqualFold(pathValue, root) {
+			return "", true
+		}
+		if strings.HasPrefix(strings.ToLower(pathValue), strings.ToLower(prefix)) {
+			return strings.TrimPrefix(pathValue, prefix), true
+		}
+		return "", false
+	}
+	cleanPath := filepath.Clean(pathValue)
+	cleanRoot := filepath.Clean(root)
+	rel, err := filepath.Rel(cleanRoot, cleanPath)
+	if err != nil || rel == "." || strings.HasPrefix(rel, "..") || filepath.IsAbs(rel) {
+		return "", false
+	}
+	return rel, true
+}
+
+func firstLibraryRootLabel(pathValue string) string {
+	pathValue = strings.TrimSpace(pathValue)
+	if pathValue == "" {
+		return ""
+	}
+	if strings.HasPrefix(strings.ToLower(pathValue), "cloud://") {
+		parts := strings.Split(strings.Trim(pathValue, "/"), "/")
+		if len(parts) > 0 {
+			return parts[len(parts)-1]
+		}
+	}
+	base := filepath.Base(filepath.Clean(pathValue))
+	if base == "." || base == string(filepath.Separator) {
+		return pathValue
+	}
+	return base
+}
+
 // mediaSearchIndexSchemaVersion identifies the physical FTS index layout.
 // v2 aligns FTS rowids with media rowids and keeps the index current with
 // triggers.