From 4e63c622e464b6863dfec0b6c99f95833f46b12f Mon Sep 17 00:00:00 2001
From: Alexander Kiryukhin <a.kiryukhin@mail.ru>
Date: Mon, 17 Aug 2020 13:42:24 +0300
Subject: [PATCH] Detached AsBytes method

---
 main.go           |  6 +++++-
 pkg/static/map.go | 10 +++++++---
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/main.go b/main.go
index 80c5f31..e48230b 100644
--- a/main.go
+++ b/main.go
@@ -44,7 +44,11 @@ func main() {
 		if err != nil {
 			return err
 		}
-		return c.Blob(200, "image/png", img)
+		blob, err := static.AsBytes(img)
+		if err != nil {
+			return err
+		}
+		return c.Blob(200, "image/png", blob)
 	})
 	log.Fatal(e.Start(":8000"))
 }
diff --git a/pkg/static/map.go b/pkg/static/map.go
index 2597aaf..8de861f 100644
--- a/pkg/static/map.go
+++ b/pkg/static/map.go
@@ -26,7 +26,7 @@ const (
 	th       = 256
 )
 
-func GetMapImage(lat, lon float64, zoom, width, height int) ([]byte, error) {
+func GetMapImage(lat, lon float64, zoom, width, height int) (image.Image, error) {
 	x, y, dx, dy := getCoords(lat, lon, zoom)
 	dst := imaging.New(width, height, color.NRGBA{0, 255, 0, 255})
 	wg := sync.WaitGroup{}
@@ -57,13 +57,17 @@ func GetMapImage(lat, lon float64, zoom, width, height int) ([]byte, error) {
 				tx := cx + i*tw - di
 				ty := cy + j*th - dj
 				dst = imaging.Paste(dst, img, image.Pt(tx, ty))
-			}(int(i), int(j))
+			}(i, j)
 		}
 	}
 	wg.Wait()
 
+	return dst, nil
+}
+
+func AsBytes(image image.Image) ([]byte,error)  {
 	out := bytes.NewBuffer([]byte{})
-	if err := imaging.Encode(out, dst, imaging.PNG); err != nil {
+	if err := imaging.Encode(out, image, imaging.PNG); err != nil {
 		return nil, err
 	}
 	return out.Bytes(), nil