[MM-29241] Image logic refactor (#17702)

* Image logic refactor

* Add missing translations

* Improve prepareImage

* Use iota

* Limit image encoder concurrency

* Unexport validation methods

* Avoid shortening on exported names

* Remove unnecessary complexity

app/user.go

@@ -14,8 +14,6 @@ import (
 	"image"
 	"image/color"
 	"image/draw"
-	_ "image/gif"
-	_ "image/jpeg"
 	"image/png"
 	"io"
 	"io/ioutil"
@@ -25,10 +23,10 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/disintegration/imaging"
 	"github.com/golang/freetype"
 	"github.com/golang/freetype/truetype"
 
+	"github.com/mattermost/mattermost-server/v5/app/imaging"
 	"github.com/mattermost/mattermost-server/v5/app/request"
 	"github.com/mattermost/mattermost-server/v5/einterfaces"
 	"github.com/mattermost/mattermost-server/v5/model"
@@ -894,39 +892,29 @@ func (a *App) SetProfileImage(userID string, imageData *multipart.FileHeader) *m
 }
 
 func (a *App) SetProfileImageFromMultiPartFile(userID string, file multipart.File) *model.AppError {
-	// Decode image config first to check dimensions before loading the whole thing into memory later on
-	config, _, err := image.DecodeConfig(file)
-	if err != nil {
-		return model.NewAppError("SetProfileImage", "api.user.upload_profile_user.decode_config.app_error", nil, err.Error(), http.StatusBadRequest)
+	if limitErr := checkImageLimits(file); limitErr != nil {
+		return model.NewAppError("SetProfileImage", "api.user.upload_profile_user.check_image_limits.app_error", nil, "", http.StatusBadRequest)
 	}
-	// This casting is done to prevent overflow on 32 bit systems (not needed
-	// in 64 bits systems because images can't have more than 32 bits height or
-	// width)
-	if int64(config.Width)*int64(config.Height) > model.MaxImageSize {
-		return model.NewAppError("SetProfileImage", "api.user.upload_profile_user.too_large.app_error", nil, "", http.StatusBadRequest)
-	}
-
-	file.Seek(0, 0)
 
 	return a.SetProfileImageFromFile(userID, file)
 }
 
 func (a *App) AdjustImage(file io.Reader) (*bytes.Buffer, *model.AppError) {
 	// Decode image into Image object
-	img, _, err := image.Decode(file)
+	img, _, err := a.srv.imgDecoder.Decode(file)
 	if err != nil {
 		return nil, model.NewAppError("SetProfileImage", "api.user.upload_profile_user.decode.app_error", nil, err.Error(), http.StatusBadRequest)
 	}
 
-	orientation, _ := getImageOrientation(file)
-	img = makeImageUpright(img, orientation)
+	orientation, _ := imaging.GetImageOrientation(file)
+	img = imaging.MakeImageUpright(img, orientation)
 
 	// Scale profile image
 	profileWidthAndHeight := 128
-	img = imaging.Fill(img, profileWidthAndHeight, profileWidthAndHeight, imaging.Center, imaging.Lanczos)
+	img = imaging.FillCenter(img, profileWidthAndHeight, profileWidthAndHeight)
 
 	buf := new(bytes.Buffer)
-	err = png.Encode(buf, img)
+	err = a.srv.imgEncoder.EncodePNG(buf, img)
 	if err != nil {
 		return nil, model.NewAppError("SetProfileImage", "api.user.upload_profile_user.encode.app_error", nil, err.Error(), http.StatusInternalServerError)
 	}