V2 alpha - initial version (#172)

Initial alpha codebase for version 2 of WireGuard Portal.
This version is considered unstable and incomplete (for example, no public REST API)! 
Use with care!


Fixes/Implements the following issues:
 - OAuth support #154, #1 
 - New Web UI with internationalisation support #98, #107, #89, #62
 - Postgres Support #49 
 - Improved Email handling #47, #119 
 - DNS Search Domain support #46 
 - Bugfixes #94, #48 

---------

Co-authored-by: Fabian Wechselberger <wechselbergerf@hotmail.com>

internal/app/configfile/qrwriter.go

@@ -0,0 +1,88 @@
+package configfile
+
+// waiting for https://github.com/yeqown/go-qrcode/pull/85 to get merged
+// meanwhile we use our own writer implementation
+
+import (
+	"image"
+	"image/color"
+	"image/png"
+	"io"
+
+	"github.com/yeqown/go-qrcode/v2"
+)
+
+type Option struct {
+	Padding   int
+	BlockSize int
+}
+
+// compressedWriter implements issue#69, generating compressed images
+// in some special situations, such as, network transferring.
+// https://github.com/yeqown/go-qrcode/issues/69
+type compressedWriter struct {
+	fd io.WriteCloser
+
+	option *Option
+}
+
+var (
+	backgroundColor = color.Gray{Y: 0xff}
+	foregroundColor = color.Gray{Y: 0x00}
+)
+
+func NewCompressedWriter(writer io.WriteCloser, opt *Option) qrcode.Writer {
+	return compressedWriter{fd: writer, option: opt}
+}
+
+func (w compressedWriter) Write(mat qrcode.Matrix) error {
+	padding := w.option.Padding
+	blockWidth := w.option.BlockSize
+	width := mat.Width()*blockWidth + 2*padding
+	height := width
+
+	img := image.NewPaletted(
+		image.Rect(0, 0, width, height),
+		color.Palette([]color.Color{backgroundColor, foregroundColor}),
+	)
+	bgColor := uint8(img.Palette.Index(backgroundColor))
+	fgColor := uint8(img.Palette.Index(foregroundColor))
+
+	rectangle := func(x1, y1 int, x2, y2 int, img *image.Paletted, color uint8) {
+		for x := x1; x < x2; x++ {
+			for y := y1; y < y2; y++ {
+				pos := img.PixOffset(x, y)
+				img.Pix[pos] = color
+			}
+		}
+	}
+
+	// background
+	rectangle(0, 0, width, height, img, bgColor)
+
+	mat.Iterate(qrcode.IterDirection_COLUMN, func(x int, y int, v qrcode.QRValue) {
+		sx := x*blockWidth + padding
+		sy := y*blockWidth + padding
+		es := (x+1)*blockWidth + padding
+		ey := (y+1)*blockWidth + padding
+
+		if v.IsSet() {
+			rectangle(sx, sy, es, ey, img, fgColor)
+		}
+
+		//switch v.IsSet() {
+		//case false:
+		//	gray = backgroundColor
+		//default:
+		//	gray = foregroundColor
+		//}
+
+	})
+
+	encoder := png.Encoder{CompressionLevel: png.BestCompression}
+	return encoder.Encode(w.fd, img)
+}
+
+func (w compressedWriter) Close() error {
+	return w.fd.Close()
+}