feat: add banner support for communities

Add banner image as a special `IdentityImage` beside "thumbnail" and "large"

Banner input cropped image processing

- Resize to keep in the limits of `BannerDim`
- Encode to match the file size limits define for banner
- Don't scale up. This can be done efficiently in the UI

Changes to `images` module

- Refactor `EncodeToBestSize` as `EncodeToLimits` to accept arbitrary dimensions
  and allow for custom size
- Define `DimensionLimits` for banner not to exceed 450 KB and a rough estimate
  for the ideal size

images/cropped_image.go

@@ -0,0 +1,9 @@
+package images
+
+type CroppedImage struct {
+	ImagePath string `json:"imagePath"`
+	X         int    `json:"x"`
+	Y         int    `json:"y"`
+	Width     int    `json:"width"`
+	Height    int    `json:"height"`
+}

images/encode.go

@@ -25,7 +25,7 @@ func renderJpeg(w io.Writer, m image.Image, config EncodeConfig) error {
 	return jpeg.Encode(w, m, o)
 }
 
-func EncodeToBestSize(bb *bytes.Buffer, img image.Image, size ResizeDimension) error {
+func EncodeToLimits(bb *bytes.Buffer, img image.Image, bounds DimensionLimits) error {
 	q := MaxJpegQuality
 	for q > MinJpegQuality-1 {
 
@@ -34,17 +34,17 @@ func EncodeToBestSize(bb *bytes.Buffer, img image.Image, size ResizeDimension) e
 			return err
 		}
 
-		if DimensionSizeLimit[size].Ideal > bb.Len() {
+		if bounds.Ideal > bb.Len() {
 			return nil
 		}
 
 		if q == MinJpegQuality {
-			if DimensionSizeLimit[size].Max > bb.Len() {
+			if bounds.Max > bb.Len() {
 				return nil
 			}
 			return fmt.Errorf(
 				"image size after processing exceeds max, expect < '%d', received < '%d'",
-				DimensionSizeLimit[size].Max,
+				bounds.Max,
 				bb.Len(),
 			)
 		}
@@ -56,6 +56,10 @@ func EncodeToBestSize(bb *bytes.Buffer, img image.Image, size ResizeDimension) e
 	return nil
 }
 
+func EncodeToBestSize(bb *bytes.Buffer, img image.Image, size ResizeDimension) error {
+	return EncodeToLimits(bb, img, DimensionSizeLimit[size])
+}
+
 func GetPayloadDataURI(payload []byte) (string, error) {
 	if len(payload) == 0 {
 		return "", nil

images/main.go

@@ -64,3 +64,41 @@ func GenerateIdentityImagesFromURL(url string) ([]*IdentityImage, error) {
 
 	return GenerateImageVariants(cImg)
 }
+
+func GenerateBannerImage(filepath string, aX, aY, bX, bY int) (*IdentityImage, error) {
+	img, err := Decode(filepath)
+	if err != nil {
+		return nil, err
+	}
+
+	cropRect := image.Rectangle{
+		Min: image.Point{X: aX, Y: aY},
+		Max: image.Point{X: bX, Y: bY},
+	}
+	croppedImg, err := Crop(img, cropRect)
+	if err != nil {
+		return nil, err
+	}
+
+	dimension := BannerDim
+	resizedImg := ShrinkOnly(dimension, croppedImg)
+
+	sizeLimits := GetBannerDimensionLimits()
+
+	bb := bytes.NewBuffer([]byte{})
+	err = EncodeToLimits(bb, resizedImg, sizeLimits)
+	if err != nil {
+		return nil, err
+	}
+
+	ii := &IdentityImage{
+		Name:         BannerIdentityName,
+		Payload:      bb.Bytes(),
+		Width:        resizedImg.Bounds().Dx(),
+		Height:       resizedImg.Bounds().Dy(),
+		FileSize:     bb.Len(),
+		ResizeTarget: int(dimension),
+	}
+
+	return ii, nil
+}

images/main_test.go

@@ -0,0 +1,46 @@
+package images
+
+import (
+	"image"
+	"image/png"
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGenerateBannerImage_NoScaleUp(t *testing.T) {
+	// Test image 256x256
+	testImage := path + "status.png"
+	identityImage, err := GenerateBannerImage(testImage, 50, 50, 150, 100)
+
+	require.NoError(t, err)
+	require.Exactly(t, identityImage.Name, BannerIdentityName)
+	require.Positive(t, len(identityImage.Payload))
+	// Ensure we don't scale it up. That will be done inefficiently in backend instead of frontend
+	require.Exactly(t, identityImage.Width, 100)
+	require.Exactly(t, identityImage.Height, 50)
+	require.Exactly(t, identityImage.FileSize, len(identityImage.Payload))
+	require.Exactly(t, identityImage.ResizeTarget, int(BannerDim))
+}
+
+func TestGenerateBannerImage_ShrinkOnly(t *testing.T) {
+	// Generate test image bigger than BannerDim
+	testImage := image.NewRGBA(image.Rect(0, 0, int(BannerDim)+10, int(BannerDim)+20))
+
+	tmpTestFilePath := t.TempDir() + "/test.png"
+	file, err := os.Create(tmpTestFilePath)
+	require.NoError(t, err)
+	defer file.Close()
+
+	err = png.Encode(file, testImage)
+	require.NoError(t, err)
+
+	identityImage, error := GenerateBannerImage(tmpTestFilePath, 0, 0, int(BannerDim)+5, int(BannerDim)+10)
+
+	require.NoError(t, error)
+	require.Positive(t, len(identityImage.Payload))
+	// Ensure we scale it down by the small side
+	require.Exactly(t, identityImage.Width, int(BannerDim))
+	require.Exactly(t, identityImage.Height, 805)
+}

images/manipulation.go

@@ -3,6 +3,7 @@ package images
 import (
 	"fmt"
 	"image"
+	"math"
 
 	"github.com/nfnt/resize"
 	"github.com/oliamb/cutter"
@@ -27,6 +28,11 @@ func Resize(size ResizeDimension, img image.Image) image.Image {
 	return resize.Resize(width, height, img, resize.Bilinear)
 }
 
+func ShrinkOnly(size ResizeDimension, img image.Image) image.Image {
+	finalSize := int(math.Min(float64(size), math.Min(float64(img.Bounds().Dx()), float64(img.Bounds().Dy()))))
+	return Resize(ResizeDimension(finalSize), img)
+}
+
 func Crop(img image.Image, rect image.Rectangle) (image.Image, error) {
 
 	if img.Bounds().Max.X < rect.Max.X || img.Bounds().Max.Y < rect.Max.Y {

images/manipulation_test.go

@@ -97,6 +97,22 @@ func TestResize(t *testing.T) {
 	}
 }
 
+// Requirement of ShrinkOnly
+func TestThatResizeResizesSmallerHeightByTheSmallestSide(t *testing.T) {
+	image := image.NewRGBA(image.Rect(0, 0, 4, 2))
+	resizedImage := Resize(ResizeDimension(1), image)
+	require.Exactly(t, 2, resizedImage.Bounds().Dx())
+	require.Exactly(t, 1, resizedImage.Bounds().Dy())
+}
+
+// Requirement of ShrinkOnly
+func TestThatResizeResizesSmallerWidthByTheSmallestSide(t *testing.T) {
+	image := image.NewRGBA(image.Rect(0, 0, 4, 8))
+	resizedImage := Resize(ResizeDimension(2), image)
+	require.Exactly(t, 2, resizedImage.Bounds().Dx())
+	require.Exactly(t, 4, resizedImage.Bounds().Dy())
+}
+
 func TestCrop(t *testing.T) {
 	type params struct {
 		Rectangle   image.Rectangle

images/meta.go

@@ -17,8 +17,12 @@ const (
 	SmallDim = ResizeDimension(80)
 	LargeDim = ResizeDimension(240)
 
+	BannerDim = ResizeDimension(800)
+
 	SmallDimName = "thumbnail"
 	LargeDimName = "large"
+
+	BannerIdentityName = "banner"
 )
 
 var (
@@ -58,3 +62,10 @@ type DimensionLimits struct {
 
 type ImageType uint
 type ResizeDimension uint
+
+func GetBannerDimensionLimits() DimensionLimits {
+	return DimensionLimits{
+		Ideal: 307200, // We want to save space and traffic but keep to maximum compression
+		Max:   460800, // Can't go bigger than 450 KB
+	}
+}

protocol/communities/manager.go

@@ -303,7 +303,7 @@ func (m *Manager) CreateCommunity(request *requests.CreateCommunity) (*Community
 	return community, nil
 }
 
-// CreateCommunity takes a description, updates the community with the description,
+// EditCommunity takes a description, updates the community with the description,
 // saves it and returns it
 func (m *Manager) EditCommunity(request *requests.EditCommunity) (*Community, error) {
 	community, err := m.GetByID(request.CommunityID)
@@ -326,11 +326,18 @@ func (m *Manager) EditCommunity(request *requests.EditCommunity) (*Community, er
 	if newDescription.Permissions.Access == protobuf.CommunityPermissions_UNKNOWN_ACCESS {
 		newDescription.Permissions.Access = community.config.CommunityDescription.Permissions.Access
 	}
-	// If the image wasn't edited, use the existing one
+	// Use existing images for the entries that were not updated
 	// NOTE: This will NOT allow deletion of the community image; it will need to
 	// be handled separately.
-	if request.Image == "" {
+	for imageName := range community.config.CommunityDescription.Identity.Images {
-		newDescription.Identity.Images = community.config.CommunityDescription.Identity.Images
+		_, exists := newDescription.Identity.Images[imageName]
+		if !exists {
+			// If no image was set in ToCommunityDescription then Images is nil.
+			if newDescription.Identity.Images == nil {
+				newDescription.Identity.Images = make(map[string]*protobuf.IdentityImage)
+			}
+			newDescription.Identity.Images[imageName] = community.config.CommunityDescription.Identity.Images[imageName]
+		}
 	}
 	// TODO: handle delete image (if needed)
 

protocol/communities/manager_test.go

@@ -2,6 +2,8 @@ package communities
 
 import (
 	"bytes"
+	"image"
+	"image/png"
 	"io/ioutil"
 	"os"
 	"testing"
@@ -9,6 +11,7 @@ import (
 
 	"github.com/status-im/status-go/appdatabase"
 	"github.com/status-im/status-go/eth-node/types"
+	userimages "github.com/status-im/status-go/images"
 	"github.com/status-im/status-go/params"
 	"github.com/status-im/status-go/protocol/requests"
 	"github.com/status-im/status-go/protocol/transport"
@@ -76,6 +79,45 @@ func (s *ManagerSuite) TestCreateCommunity() {
 	s.Require().True(proto.Equal(community.config.CommunityDescription, actualCommunity.config.CommunityDescription))
 }
 
+func (s *ManagerSuite) TestCreateCommunity_WithBanner() {
+	// Generate test image bigger than BannerDim
+	testImage := image.NewRGBA(image.Rect(0, 0, 20, 10))
+
+	tmpTestFilePath := s.T().TempDir() + "/test.png"
+	file, err := os.Create(tmpTestFilePath)
+	s.NoError(err)
+	defer file.Close()
+
+	err = png.Encode(file, testImage)
+	s.Require().NoError(err)
+
+	request := &requests.CreateCommunity{
+		Name:        "with_banner",
+		Description: "community with banner ",
+		Membership:  protobuf.CommunityPermissions_NO_MEMBERSHIP,
+		Banner: userimages.CroppedImage{
+			ImagePath: tmpTestFilePath,
+			X:         1,
+			Y:         1,
+			Width:     10,
+			Height:    5,
+		},
+	}
+
+	community, err := s.manager.CreateCommunity(request)
+	s.Require().NoError(err)
+	s.Require().NotNil(community)
+
+	communities, err := s.manager.All()
+	s.Require().NoError(err)
+	// Consider status default community
+	s.Require().Len(communities, 2)
+	s.Require().Equal(len(community.config.CommunityDescription.Identity.Images), 1)
+	testIdentityImage, isMapContainsKey := community.config.CommunityDescription.Identity.Images[userimages.BannerIdentityName]
+	s.Require().True(isMapContainsKey)
+	s.Require().Positive(len(testIdentityImage.Payload))
+}
+
 func (s *ManagerSuite) TestEditCommunity() {
 	//create community
 	createRequest := &requests.CreateCommunity{

protocol/requests/create_community_request.go

@@ -28,6 +28,7 @@ type CreateCommunity struct {
 	ImageAy                      int                                  `json:"imageAy"`
 	ImageBx                      int                                  `json:"imageBx"`
 	ImageBy                      int                                  `json:"imageBy"`
+	Banner                       userimages.CroppedImage              `json:"banner"`
 	HistoryArchiveSupportEnabled bool                                 `json:"historyArchiveSupportEnabled,omitempty"`
 	PinMessageAllMembersEnabled  bool                                 `json:"pinMessageAllMembersEnabled,omitempty"`
 }
@@ -68,9 +69,10 @@ func (c *CreateCommunity) ToCommunityDescription() (*protobuf.CommunityDescripti
 		Description: c.Description,
 	}
 
+	if c.Image != "" || c.Banner.ImagePath != "" {
+		ciis := make(map[string]*protobuf.IdentityImage)
 		if c.Image != "" {
 			log.Info("has-image", "image", c.Image)
-		ciis := make(map[string]*protobuf.IdentityImage)
 			imgs, err := userimages.GenerateIdentityImages(c.Image, c.ImageAx, c.ImageAy, c.ImageBx, c.ImageBy)
 			if err != nil {
 				return nil, err
@@ -78,6 +80,15 @@ func (c *CreateCommunity) ToCommunityDescription() (*protobuf.CommunityDescripti
 			for _, img := range imgs {
 				ciis[img.Name] = adaptIdentityImageToProtobuf(img)
 			}
+		}
+		if c.Banner.ImagePath != "" {
+			log.Info("has-banner", "image", c.Banner.ImagePath)
+			img, err := userimages.GenerateBannerImage(c.Banner.ImagePath, c.Banner.X, c.Banner.Y, c.Banner.X+c.Banner.Width, c.Banner.Y+c.Banner.Height)
+			if err != nil {
+				return nil, err
+			}
+			ciis[img.Name] = adaptIdentityImageToProtobuf(img)
+		}
 		ci.Images = ciis
 		log.Info("set images", "images", ci)
 	}