Initial QSfera import

Server/services/thumbnails/pkg/thumbnail/generator_simple.go

@@ -0,0 +1,46 @@
+//go:build !enable_vips
+
+package thumbnail
+
+import (
+	"image"
+
+	"github.com/kovidgoyal/imaging"
+	"github.com/qsfera/server/services/thumbnails/pkg/errors"
+)
+
+// SimpleGenerator is the default image generator and is used for all image types expect gif.
+type SimpleGenerator struct {
+	processor Processor
+}
+
+func NewSimpleGenerator(filetype, process string) (SimpleGenerator, error) {
+	processor, err := ProcessorFor(process, filetype)
+	if err != nil {
+		return SimpleGenerator{}, err
+	}
+	return SimpleGenerator{processor: processor}, nil
+}
+
+// ProcessorID returns the processor identification.
+func (g SimpleGenerator) ProcessorID() string {
+	return g.processor.ID()
+}
+
+// Generate generates a alternative image version.
+func (g SimpleGenerator) Generate(size image.Rectangle, img any) (any, error) {
+	m, ok := img.(image.Image)
+	if !ok {
+		return nil, errors.ErrInvalidType
+	}
+
+	return g.processor.Process(m, size.Dx(), size.Dy(), imaging.Lanczos), nil
+}
+
+func (g SimpleGenerator) Dimensions(img any) (image.Rectangle, error) {
+	m, ok := img.(image.Image)
+	if !ok {
+		return image.Rectangle{}, errors.ErrInvalidType
+	}
+	return m.Bounds(), nil
+}