feat: Add album scanner

8 files changed, 320 insertions, 11 deletions

diff --git a/pkg/database/repository/media.go b/pkg/database/repository/media.go
index 6f5b39b..d6addbf 100644
--- a/pkg/database/repository/media.go
+++ b/pkg/database/repository/media.go
@@ -34,6 +34,10 @@ type (
 		GPSLongitude    *float64
 	}
 
+	Album struct {
+		ID uint
+	}
+
 	MediaThumbnail struct {
 		Path string
 	}
@@ -51,6 +55,17 @@ type (
 		MIMEType string
 	}
 
+	CreateAlbum struct {
+		ParentID *uint
+		Name     string
+		Path     string
+	}
+
+	CreateAlbumFile struct {
+		MediaID uint
+		AlbumID uint
+	}
+
 	MediaRepository interface {
 		Create(context.Context, *CreateMedia) error
 		Exists(context.Context, string) (bool, error)
@@ -66,6 +81,12 @@ type (
 		ListEmptyThumbnail(context.Context, *Pagination) ([]*Media, error)
 		GetThumbnail(context.Context, uint) (*MediaThumbnail, error)
 		CreateThumbnail(context.Context, uint, *MediaThumbnail) error
+
+		ListEmptyAlbums(context.Context, *Pagination) ([]*Media, error)
+		ExistsAlbumByAbsolutePath(context.Context, string) (bool, error)
+		GetAlbumByAbsolutePath(context.Context, string) (*Album, error)
+		CreateAlbum(context.Context, *CreateAlbum) (*Album, error)
+		CreateAlbumFile(context.Context, *CreateAlbumFile) error
 	}
 )
 
diff --git a/pkg/database/sql/media.go b/pkg/database/sql/media.go
index e5ba517..59e39ee 100644
--- a/pkg/database/sql/media.go
+++ b/pkg/database/sql/media.go
@@ -48,6 +48,22 @@ type (
 		Media   Media
 	}
 
+	MediaAlbum struct {
+		gorm.Model
+		ParentID *uint
+		Parent   *MediaAlbum
+		Name     string
+		Path     string
+	}
+
+	MediaAlbumFile struct {
+		gorm.Model
+		MediaID uint
+		Media   Media
+		AlbumID uint
+		Album   MediaAlbum
+	}
+
 	MediaRepository struct {
 		db *gorm.DB
 	}
@@ -55,13 +71,13 @@ type (
 
 var _ repository.MediaRepository = &MediaRepository{}
 
-func (self *Media) ToModel() *repository.Media {
+func (m *Media) ToModel() *repository.Media {
 	return &repository.Media{
-		ID:       self.ID,
-		Path:     self.Path,
-		PathHash: self.PathHash,
-		Name:     self.Name,
-		MIMEType: self.MIMEType,
+		ID:       m.ID,
+		Path:     m.Path,
+		PathHash: m.PathHash,
+		Name:     m.Name,
+		MIMEType: m.MIMEType,
 	}
 }
 
@@ -86,6 +102,12 @@ func (m *MediaEXIF) ToModel() *repository.MediaEXIF {
 	}
 }
 
+func (a *MediaAlbum) ToModel() *repository.Album {
+	return &repository.Album{
+		ID: a.ID,
+	}
+}
+
 func (m *MediaThumbnail) ToModel() *repository.MediaThumbnail {
 	return &repository.MediaThumbnail{
 		Path: m.Path,
@@ -329,3 +351,91 @@ func (m *MediaRepository) CreateThumbnail(ctx context.Context, mediaID uint, thu
 
 	return nil
 }
+
+func (r *MediaRepository) ListEmptyAlbums(ctx context.Context, pagination *repository.Pagination) ([]*repository.Media, error) {
+	medias := make([]*Media, 0)
+	result := r.db.
+		WithContext(ctx).
+		Model(&Media{}).
+		Joins("left join media_album_files on media.id = media_album_files.media_id").
+		Where("media_album_files.media_id IS NULL").
+		Offset(pagination.Page * pagination.Size).
+		Limit(pagination.Size).
+		Order("media.created_at DESC").
+		Find(&medias)
+
+	if result.Error != nil {
+		return nil, result.Error
+	}
+
+	m := list.Map(medias, func(s *Media) *repository.Media {
+		return s.ToModel()
+	})
+
+	return m, nil
+}
+
+func (m *MediaRepository) ExistsAlbumByAbsolutePath(ctx context.Context, path string) (bool, error) {
+	var exists bool
+	result := m.db.
+		WithContext(ctx).
+		Model(&MediaAlbum{}).
+		Select("count(id) > 0").
+		Where("path = ?", path).
+		Find(&exists)
+
+	if result.Error != nil {
+		return false, result.Error
+	}
+
+	return exists, nil
+}
+
+func (r *MediaRepository) GetAlbumByAbsolutePath(ctx context.Context, path string) (*repository.Album, error) {
+	m := &MediaAlbum{}
+	result := r.db.
+		WithContext(ctx).
+		Model(&MediaAlbum{}).
+		Where("path = ?", path).
+		Limit(1).
+		Take(m)
+
+	if result.Error != nil {
+		return nil, result.Error
+	}
+
+	return m.ToModel(), nil
+}
+
+func (m *MediaRepository) CreateAlbum(ctx context.Context, createAlbum *repository.CreateAlbum) (*repository.Album, error) {
+	album := &MediaAlbum{
+		ParentID: createAlbum.ParentID,
+		Name:     createAlbum.Name,
+		Path:     createAlbum.Path,
+	}
+
+	result := m.db.
+		WithContext(ctx).
+		Create(album)
+	if result.Error != nil {
+		return nil, result.Error
+	}
+
+	return album.ToModel(), nil
+}
+
+func (m *MediaRepository) CreateAlbumFile(ctx context.Context, createAlbumFile *repository.CreateAlbumFile) error {
+	albumFile := &MediaAlbumFile{
+		MediaID: createAlbumFile.MediaID,
+		AlbumID: createAlbumFile.AlbumID,
+	}
+
+	result := m.db.
+		WithContext(ctx).
+		Create(albumFile)
+	if result.Error != nil {
+		return result.Error
+	}
+
+	return nil
+}
diff --git a/pkg/database/sql/migration.go b/pkg/database/sql/migration.go
index 076bf69..73e4297 100644
--- a/pkg/database/sql/migration.go
+++ b/pkg/database/sql/migration.go
@@ -9,6 +9,8 @@ func Migrate(db *gorm.DB) error {
 		&Media{},
 		&MediaEXIF{},
 		&MediaThumbnail{},
+		&MediaAlbum{},
+		&MediaAlbumFile{},
 	} {
 		if err := db.AutoMigrate(m); err != nil {
 			return err
diff --git a/pkg/list/list.go b/pkg/list/list.go
index ff259f7..dfc3fb7 100644
--- a/pkg/list/list.go
+++ b/pkg/list/list.go
@@ -7,3 +7,28 @@ func Map[V any, T any](source []V, fun func(V) T) []T {
 	}
 	return result
 }
+
+type Pair[T, U any] struct {
+	Left  T
+	Right U
+}
+
+func Zip[T, U any](left []T, right []U) []Pair[T, U] {
+	// pick the array with the smaller length
+	l := len(left)
+	if len(left) > len(right) {
+		l = len(right)
+	}
+
+	pairs := make([]Pair[T, U], len(left))
+	for i := 0; i < l; i++ {
+		pairs[i] = Pair[T, U]{left[i], right[i]}
+	}
+	return pairs
+}
+
+func Revert[T any](s []T) {
+	for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
+		s[i], s[j] = s[j], s[i]
+	}
+}
diff --git a/pkg/worker/list_processor.go b/pkg/worker/list_processor.go
index c060583..02817c9 100644
--- a/pkg/worker/list_processor.go
+++ b/pkg/worker/list_processor.go
@@ -20,7 +20,7 @@ type (
 		OnFail(context.Context, T, error)
 	}
 
-	BatchProcessor[T any] interface {
+	ListProcessor[T any] interface {
 		Query(context.Context) ([]T, error)
 		Process(context.Context, T) error
 	}
@@ -32,14 +32,20 @@ type (
 	}
 
 	batchProcessorWorker[T any] struct {
-		batchProcessor BatchProcessor[T]
+		batchProcessor ListProcessor[T]
+		logrus         *logrus.Entry
+		scheduler      *Scheduler
+	}
+
+	serialProcessorWorker[T any] struct {
+		batchProcessor ListProcessor[T]
 		logrus         *logrus.Entry
 		scheduler      *Scheduler
 	}
 )
 
 func NewWorkerFromBatchProcessor[T any](
-	batchProcessor BatchProcessor[T],
+	batchProcessor ListProcessor[T],
 	scheduler *Scheduler,
 	logrus *logrus.Entry,
 ) Worker {
@@ -50,6 +56,18 @@ func NewWorkerFromBatchProcessor[T any](
 	}
 }
 
+func NewWorkerFromSerialProcessor[T any](
+	batchProcessor ListProcessor[T],
+	scheduler *Scheduler,
+	logrus *logrus.Entry,
+) Worker {
+	return &serialProcessorWorker[T]{
+		batchProcessor: batchProcessor,
+		scheduler:      scheduler,
+		logrus:         logrus,
+	}
+}
+
 func NewWorkerFromChanProcessor[T any](
 	chanProcessor ChanProcessor[T],
 	scheduler *Scheduler,
@@ -105,6 +123,41 @@ func (l *batchProcessorWorker[T]) Start(ctx context.Context) error {
 	}
 }
 
+func (l *serialProcessorWorker[T]) Start(ctx context.Context) error {
+	for {
+		values, err := l.batchProcessor.Query(ctx)
+		if err != nil {
+			return err
+		}
+
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+		}
+
+		if len(values) == 0 {
+			return nil
+		}
+		for _, v := range values {
+			select {
+			case <-ctx.Done():
+				return ctx.Err()
+			default:
+			}
+
+			l.scheduler.Take()
+			if err := l.batchProcessor.Process(ctx, v); err != nil && !errors.Is(err, context.Canceled) {
+				l.logrus.WithError(err).Error("Error processing batch")
+				if failure, ok := l.batchProcessor.(OnFail[T]); ok {
+					failure.OnFail(ctx, v, err)
+				}
+			}
+			l.scheduler.Return()
+		}
+	}
+}
+
 func (l *chanProcessorWorker[T]) Start(ctx context.Context) error {
 	c, err := l.chanProcessor.Query(ctx)
 	if err != nil {
diff --git a/pkg/worker/scanner/album_scanner.go b/pkg/worker/scanner/album_scanner.go
new file mode 100644
index 0000000..618a184
--- /dev/null
+++ b/pkg/worker/scanner/album_scanner.go
@@ -0,0 +1,98 @@
+package scanner
+
+import (
+	"context"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"git.sr.ht/~gabrielgio/img/pkg/database/repository"
+	"git.sr.ht/~gabrielgio/img/pkg/worker"
+)
+
+type (
+	AlbumScanner struct {
+		repository repository.MediaRepository
+	}
+)
+
+var _ worker.ListProcessor[*repository.Media] = &AlbumScanner{}
+
+func NewAlbumScanner(repository repository.MediaRepository) *AlbumScanner {
+	return &AlbumScanner{
+		repository: repository,
+	}
+}
+
+func (e *AlbumScanner) Query(ctx context.Context) ([]*repository.Media, error) {
+	return e.repository.ListEmptyAlbums(ctx, &repository.Pagination{
+		Page: 0,
+		Size: 100,
+	})
+}
+
+// This process will optmize for file over folder, which means it will assume that there will be
+// more file then folder in the overall library.
+// So will try to make as cheap as possible to look for fetching many files in a folder
+// meaning it will start from checking from left to right in the path since it will assume
+// that the path to that point has been registered already, resulting in a single lookup for the media
+func (e *AlbumScanner) Process(ctx context.Context, m *repository.Media) error {
+	// we don't need the name of the file, only its path
+	filePath, _ := path.Split(m.Path)
+
+	parts := strings.Split(filePath, string(os.PathSeparator))
+
+	subPaths := FanInwards(parts)
+	album, err := e.GetAndCreateNestedAlbuns(ctx, subPaths)
+	if err != nil {
+		return err
+	}
+
+	return e.repository.CreateAlbumFile(ctx, &repository.CreateAlbumFile{
+		MediaID: m.ID,
+		AlbumID: album.ID,
+	})
+}
+
+func (e *AlbumScanner) GetAndCreateNestedAlbuns(ctx context.Context, paths []string) (*repository.Album, error) {
+	if len(paths) == 1 {
+		// end of trail, we should create a album without parent
+		return e.repository.CreateAlbum(ctx, &repository.CreateAlbum{
+			ParentID: nil,
+			Name:     filepath.Base(paths[0]),
+			Path:     paths[0],
+		})
+	}
+
+	exists, err := e.repository.ExistsAlbumByAbsolutePath(ctx, paths[0])
+	if err != nil {
+		return nil, err
+	}
+
+	if exists {
+		return e.repository.GetAlbumByAbsolutePath(ctx, paths[0])
+	}
+
+	//album does not exist, create it and get its parent id
+	a, err := e.GetAndCreateNestedAlbuns(ctx, paths[1:])
+	if err != nil {
+		return nil, err
+	}
+
+	return e.repository.CreateAlbum(ctx, &repository.CreateAlbum{
+		ParentID: &a.ID,
+		Name:     filepath.Base(paths[0]),
+		Path:     paths[0],
+	})
+
+}
+
+func FanInwards(paths []string) []string {
+	result := make([]string, 0, len(paths))
+	for i := (len(paths) - 1); i >= 0; i-- {
+		subPaths := paths[0:i]
+		result = append(result, path.Join(subPaths...))
+	}
+	return result
+}
diff --git a/pkg/worker/scanner/exif_scanner.go b/pkg/worker/scanner/exif_scanner.go
index 47d717f..da63c0b 100644
--- a/pkg/worker/scanner/exif_scanner.go
+++ b/pkg/worker/scanner/exif_scanner.go
@@ -15,7 +15,7 @@ type (
 	}
 )
 
-var _ worker.BatchProcessor[*repository.Media] = &EXIFScanner{}
+var _ worker.ListProcessor[*repository.Media] = &EXIFScanner{}
 
 func NewEXIFScanner(repository repository.MediaRepository) *EXIFScanner {
 	return &EXIFScanner{
diff --git a/pkg/worker/scanner/thumbnail_scanner.go b/pkg/worker/scanner/thumbnail_scanner.go
index 9f75464..6446c53 100644
--- a/pkg/worker/scanner/thumbnail_scanner.go
+++ b/pkg/worker/scanner/thumbnail_scanner.go
@@ -19,7 +19,7 @@ type (
 	}
 )
 
-var _ worker.BatchProcessor[*repository.Media] = &EXIFScanner{}
+var _ worker.ListProcessor[*repository.Media] = &EXIFScanner{}
 
 func NewThumbnailScanner(cachePath string, repository repository.MediaRepository) *ThumbnailScanner {
 	return &ThumbnailScanner{