arimelody.me/controller/qr.go
ari melody 3450d879ac
QR codes complete, account settings finished!
+ refactored templates a little; this might need more work!
2025-01-26 20:09:18 +00:00

121 lines
2.9 KiB
Go

package controller
import (
"bytes"
"encoding/base64"
"errors"
"fmt"
"image"
"image/color"
"image/png"
"github.com/skip2/go-qrcode"
)
func GenerateQRCode(data string) (string, error) {
imgBytes, err := qrcode.Encode(data, qrcode.Medium, 256)
if err != nil {
return "", err
}
base64Img := base64.StdEncoding.EncodeToString(imgBytes)
return base64Img, nil
}
// vvv DEPRECATED vvv
const margin = 4
type QRCodeECCLevel int64
const (
LOW QRCodeECCLevel = iota
MEDIUM
QUARTILE
HIGH
)
func noDepsGenerateQRCode() (string, error) {
version := 1
size := 0
size = 21 + version * 4
if version > 10 {
return "", errors.New(fmt.Sprintf("QR version %d not supported", version))
}
img := image.NewGray(image.Rect(0, 0, size + margin * 2, size + margin * 2))
// fill white
for y := range size + margin * 2 {
for x := range size + margin * 2 {
img.Set(x, y, color.White)
}
}
// draw alignment squares
drawLargeAlignmentSquare(margin, margin, img)
drawLargeAlignmentSquare(margin, margin + size - 7, img)
drawLargeAlignmentSquare(margin + size - 7, margin, img)
drawSmallAlignmentSquare(size - 5, size - 5, img)
/*
if version > 4 {
space := version * 3 - 2
end := size / space
for y := range size / space + 1 {
for x := range size / space + 1 {
if x == 0 && y == 0 { continue }
if x == 0 && y == end { continue }
if x == end && y == 0 { continue }
if x == end && y == end { continue }
drawSmallAlignmentSquare(
x * space + margin + 4,
y * space + margin + 4,
img,
)
}
}
}
*/
// draw timing bits
for i := margin + 6; i < size - 4; i++ {
if (i % 2 == 0) {
img.Set(i, margin + 6, color.Black)
img.Set(margin + 6, i, color.Black)
}
}
img.Set(margin + 8, size - 4, color.Black)
var imgBuf bytes.Buffer
err := png.Encode(&imgBuf, img)
if err != nil {
return "", err
}
base64Img := base64.StdEncoding.EncodeToString(imgBuf.Bytes())
return "data:image/png;base64," + base64Img, nil
}
func drawLargeAlignmentSquare(x int, y int, img *image.Gray) {
for yi := range 7 {
for xi := range 7 {
if (xi == 0 || xi == 6) || (yi == 0 || yi == 6) {
img.Set(x + xi, y + yi, color.Black)
} else if (xi > 1 && xi < 5) && (yi > 1 && yi < 5) {
img.Set(x + xi, y + yi, color.Black)
}
}
}
}
func drawSmallAlignmentSquare(x int, y int, img *image.Gray) {
for yi := range 5 {
for xi := range 5 {
if (xi == 0 || xi == 4) || (yi == 0 || yi == 4) {
img.Set(x + xi, y + yi, color.Black)
}
}
}
img.Set(x + 2, y + 2, color.Black)
}