Initialize AutoLibrary website with Gitea deployment

backend/services/themes_service/service.go

@@ -0,0 +1,117 @@
+package themes_service
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"autolibrary.top/webserver/backend/models/themes_model"
+	"autolibrary.top/webserver/backend/services/theme_files"
+
+	"gorm.io/gorm"
+)
+
+// Service coordinates database changes and their corresponding theme archive.
+type Service struct {
+	DB    *gorm.DB
+	Files *theme_files.Store
+	locks sync.Map
+}
+
+func (s *Service) lock(id uint) func() {
+	value, _ := s.locks.LoadOrStore(id, &sync.Mutex{})
+	mutex := value.(*sync.Mutex)
+	mutex.Lock()
+	return mutex.Unlock
+}
+
+func (s *Service) ArchivePath(id uint) string {
+	return filepath.Join(s.Files.Root(), fmt.Sprintf("%d.altheme", id))
+}
+
+func (s *Service) Create(theme *themes_model.Theme, qss []byte) error {
+	var path string
+	err := s.DB.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Create(theme).Error; err != nil {
+			return err
+		}
+		path = s.ArchivePath(theme.ID)
+		data, err := theme_files.CreateAlthemeArchive(qss, theme_files.BuildInfoJSON(*theme))
+		if err != nil {
+			return err
+		}
+		if err := s.Files.WriteFile(path, data, 0644); err != nil {
+			return err
+		}
+		theme.FilePath = path
+		theme.FileSize = fmt.Sprintf("%.1f KB", float64(len(data))/1024)
+		return tx.Save(theme).Error
+	})
+	if err != nil && path != "" {
+		_ = s.Files.Remove(path)
+	}
+	return err
+}
+
+func (s *Service) Save(theme *themes_model.Theme, qss []byte) error {
+	unlock := s.lock(theme.ID)
+	defer unlock()
+	path := s.ArchivePath(theme.ID)
+	previous, readErr := os.ReadFile(path)
+	if qss == nil {
+		var err error
+		qss, err = theme_files.ExtractQSSFromAltheme(path)
+		if err != nil {
+			return fmt.Errorf("cannot read existing theme archive: %w", err)
+		}
+	}
+	data, err := theme_files.CreateAlthemeArchive(qss, theme_files.BuildInfoJSON(*theme))
+	if err != nil {
+		return err
+	}
+	theme.FilePath = path
+	theme.FileSize = fmt.Sprintf("%.1f KB", float64(len(data))/1024)
+	wrote := false
+	err = s.DB.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Save(theme).Error; err != nil {
+			return err
+		}
+		if err := s.Files.WriteFile(path, data, 0644); err != nil {
+			return err
+		}
+		wrote = true
+		return nil
+	})
+	if err != nil && wrote {
+		var restoreErr error
+		if readErr == nil {
+			restoreErr = s.Files.WriteFile(path, previous, 0644)
+		} else {
+			restoreErr = s.Files.Remove(path)
+		}
+		if restoreErr != nil {
+			log.Printf("[E] archive rollback failed for theme %d: %v", theme.ID, restoreErr)
+		}
+	}
+	return err
+}
+
+func (s *Service) Delete(theme *themes_model.Theme) error {
+	unlock := s.lock(theme.ID)
+	defer unlock()
+	if err := s.DB.Delete(theme).Error; err != nil {
+		return err
+	}
+	paths := []string{s.ArchivePath(theme.ID)}
+	if theme.PreviewURL != "" {
+		paths = append(paths, filepath.Join(s.Files.Root(), "previews", filepath.Base(theme.PreviewURL)))
+	}
+	for _, path := range paths {
+		if err := s.Files.Remove(path); err != nil {
+			log.Printf("[W] theme %d file cleanup: %v", theme.ID, err)
+		}
+	}
+	return nil
+}