sklad/label-exp/main.go

464 lines
11 KiB
Go

package main
import (
"errors"
"html/template"
"image"
"image/color"
"image/draw"
"image/png"
"io"
"log"
"net/http"
"os"
"strconv"
"time"
"github.com/boombuler/barcode"
"github.com/boombuler/barcode/qr"
"janouch.name/sklad/bdf"
)
// scaler is a scaling image.Image wrapper.
type scaler struct {
image image.Image
scale int
}
// ColorModel implements image.Image.
func (s *scaler) ColorModel() color.Model {
return s.image.ColorModel()
}
// Bounds implements image.Image.
func (s *scaler) Bounds() image.Rectangle {
r := s.image.Bounds()
return image.Rect(r.Min.X*s.scale, r.Min.Y*s.scale,
r.Max.X*s.scale, r.Max.Y*s.scale)
}
// At implements image.Image.
func (s *scaler) At(x, y int) color.Color {
if x < 0 {
x = x - s.scale + 1
}
if y < 0 {
y = y - s.scale + 1
}
return s.image.At(x/s.scale, y/s.scale)
}
// leftRotate is a 90 degree rotating image.Image wrapper.
type leftRotate struct {
image image.Image
}
// ColorModel implements image.Image.
func (lr *leftRotate) ColorModel() color.Model {
return lr.image.ColorModel()
}
// Bounds implements image.Image.
func (lr *leftRotate) Bounds() image.Rectangle {
r := lr.image.Bounds()
// Min is inclusive, Max is exclusive.
return image.Rect(r.Min.Y, -(r.Max.X - 1), r.Max.Y, -(r.Min.X - 1))
}
// At implements image.Image.
func (lr *leftRotate) At(x, y int) color.Color {
return lr.image.At(-y, x)
}
// -----------------------------------------------------------------------------
func decodeBitfieldErrors(b byte, errors [8]string) []string {
var result []string
for i := uint(0); i < 8; i++ {
if b&(1<<i) != 0 {
result = append(result, errors[i])
}
}
return result
}
func printStatusInformation(d []byte) {
log.Println("-- status")
// Error information 1.
for _, e := range decodeBitfieldErrors(d[8], [8]string{
"no media", "end of media", "cutter jam", "?", "printer in use",
"printer turned off", "high-voltage adapter", "fan motor error"}) {
log.Println("error:", e)
}
// Error information 2.
for _, e := range decodeBitfieldErrors(d[9], [8]string{
"replace media", "expansion buffer full", "communication error",
"communication buffer full", "cover open", "cancel key",
"media cannot be fed", "system error"}) {
log.Println("error:", e)
}
// Media width.
log.Println("media width:", d[10], "mm")
// Media type.
switch b := d[11]; b {
case 0x00:
log.Println("media: no media")
case 0x4a:
log.Println("media: continuous length tape")
case 0x4b:
log.Println("media: die-cut labels")
default:
log.Println("media:", b)
}
// Mode.
log.Println("mode:", d[15])
// Media length.
log.Println("media width:", d[17], "mm")
// Status type.
switch b := d[18]; b {
case 0x00:
log.Println("status type: reply to status request")
case 0x01:
log.Println("status type: printing completed")
case 0x02:
log.Println("status type: error occurred")
case 0x04:
log.Println("status type: turned off")
case 0x05:
log.Println("status type: notification")
case 0x06:
log.Println("status type: phase change")
default:
log.Println("status type:", b)
}
// Phase type.
switch b := d[19]; b {
case 0x00:
log.Println("phase state: receiving state")
case 0x01:
log.Println("phase state: printing state")
default:
log.Println("phase state:", b)
}
// Phase number.
log.Println("phase number:", int(d[20])*256+int(d[21]))
// Notification number.
switch b := d[22]; b {
case 0x00:
log.Println("notification number: not available")
case 0x03:
log.Println("notification number: cooling (started)")
case 0x04:
log.Println("notification number: cooling (finished)")
default:
log.Println("notification number:", b)
}
}
// genLabelData converts an image to the printer's raster format.
func genLabelData(src image.Image, offset int) (data []byte) {
// TODO: Margins? For 29mm, it's 6 pins from the start, 306 printing pins.
bounds := src.Bounds()
pixels := make([]bool, 720)
for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
off := offset
for x := bounds.Max.X - 1; x >= bounds.Min.X; x-- {
// TODO: Anything to do with the ColorModel?
r, g, b, a := src.At(x, y).RGBA()
pixels[off] = r == 0 && g == 0 && b == 0 && a != 0
off++
}
data = append(data, 'g', 0x00, 90)
for i := 0; i < 90; i++ {
var b byte
for j := 0; j < 8; j++ {
b <<= 1
if pixels[i*8+j] {
b |= 1
}
}
data = append(data, b)
}
}
return
}
func printLabel(src image.Image) error {
data := []byte(nil)
// Raster mode.
// Should be the only supported mode for QL-800.
data = append(data, 0x1b, 0x69, 0x61, 0x01)
// Automatic status mode (though it's the default).
data = append(data, 0x1b, 0x69, 0x21, 0x00)
// Print information command.
dy := src.Bounds().Dy()
data = append(data, 0x1b, 0x69, 0x7a, 0x02|0x04|0x40|0x80, 0x0a, 29, 0,
byte(dy), byte(dy>>8), byte(dy>>16), byte(dy>>24), 0, 0x00)
// Auto cut, each 1 label.
data = append(data, 0x1b, 0x69, 0x4d, 0x40)
data = append(data, 0x1b, 0x69, 0x41, 0x01)
// Cut at end (though it's the default).
// Not sure what it means, doesn't seem to have any effect to turn it off.
data = append(data, 0x1b, 0x69, 0x4b, 0x08)
// 3mm margins along the direction of feed. 0x23 = 35 dots, the minimum.
data = append(data, 0x1b, 0x69, 0x64, 0x23, 0x00)
// Compression mode: no compression.
// Should be the only supported mode for QL-800.
data = append(data, 0x4d, 0x00)
// The graphics data itself.
data = append(data, genLabelData(src, 6)...)
// Print command with feeding.
data = append(data, 0x1a)
// ---
// Linux usblp module, located in /drivers/usb/class/usblp.c
// (at least that's where the trails go, I don't understand the code)
f, err := os.OpenFile("/dev/usb/lp0", os.O_RDWR, 0)
if err != nil {
return err
}
defer f.Close()
// Flush any former responses in the printer's queue.
for {
dummy := make([]byte, 32)
if _, err := f.Read(dummy); err == io.EOF {
break
}
}
// Clear the print buffer.
invalidate := make([]byte, 400)
if _, err := f.Write(invalidate); err != nil {
return err
}
// Initialize.
if _, err := f.WriteString("\x1b\x40"); err != nil {
return err
}
// Request status information.
if _, err := f.WriteString("\x1b\x69\x53"); err != nil {
return err
}
// We need to poll the device.
status := make([]byte, 32)
for {
if n, err := f.Read(status); err == io.EOF {
time.Sleep(10 * time.Millisecond)
} else if err != nil {
return err
} else if n < 32 {
return errors.New("invalid read")
} else {
break
}
}
printStatusInformation(status)
// Print the prepared data.
if _, err := f.Write(data); err != nil {
return err
}
// TODO: We specifically need to wait for a transition to the receiving
// state, and try to figure out something from the statuses.
// We may also receive an error status instead of the transition to
// the printing state. Or even after it.
start := time.Now()
for {
if time.Now().Sub(start) > 3*time.Second {
break
}
if n, err := f.Read(status); err == io.EOF {
time.Sleep(100 * time.Millisecond)
} else if err != nil {
return err
} else if n < 32 {
return errors.New("invalid read")
} else {
printStatusInformation(status)
}
}
return nil
}
// -----------------------------------------------------------------------------
var font *bdf.Font
func genLabel(text string, width int) image.Image {
// Create a scaled bitmap of the QR code.
qrImg, _ := qr.Encode(text, qr.H, qr.Auto)
qrImg, _ = barcode.Scale(qrImg, width, width)
qrRect := qrImg.Bounds()
// Create a scaled bitmap of the text label.
textRect, _ := font.BoundString(text)
textImg := image.NewRGBA(textRect)
draw.Draw(textImg, textRect, image.White, image.ZP, draw.Src)
font.DrawString(textImg, image.ZP, text)
// TODO: We can scale as needed to make the text fit.
scaledTextImg := scaler{image: textImg, scale: 3}
scaledTextRect := scaledTextImg.Bounds()
// Combine.
combinedRect := qrRect
combinedRect.Max.Y += scaledTextRect.Dy() + 20
combinedImg := image.NewRGBA(combinedRect)
draw.Draw(combinedImg, combinedRect, image.White, image.ZP, draw.Src)
draw.Draw(combinedImg, combinedRect, qrImg, image.ZP, draw.Src)
target := image.Rect(
(width-scaledTextRect.Dx())/2, qrRect.Dy()+10,
combinedRect.Max.X, combinedRect.Max.Y)
draw.Draw(combinedImg, target, &scaledTextImg, scaledTextRect.Min, draw.Src)
return combinedImg
}
func genLabelForHeight(text string, height int) image.Image {
// Create a scaled bitmap of the text label.
textRect, _ := font.BoundString(text)
textImg := image.NewRGBA(textRect)
draw.Draw(textImg, textRect, image.White, image.ZP, draw.Src)
font.DrawString(textImg, image.ZP, text)
// TODO: Make it possible to choose scale, or use some heuristic.
scaledTextImg := scaler{image: textImg, scale: 3}
//scaledTextImg := scaler{image: textImg, scale: 3}
scaledTextRect := scaledTextImg.Bounds()
remains := height - scaledTextRect.Dy() - 20
width := scaledTextRect.Dx()
if remains > width {
width = remains
}
// Create a scaled bitmap of the QR code.
qrImg, _ := qr.Encode(text, qr.H, qr.Auto)
qrImg, _ = barcode.Scale(qrImg, remains, remains)
qrRect := qrImg.Bounds()
// Combine.
combinedRect := image.Rect(0, 0, width, height)
combinedImg := image.NewRGBA(combinedRect)
draw.Draw(combinedImg, combinedRect, image.White, image.ZP, draw.Src)
draw.Draw(combinedImg,
combinedRect.Add(image.Point{X: (width - qrRect.Dx()) / 2, Y: 0}),
qrImg, image.ZP, draw.Src)
target := image.Rect(
(width-scaledTextRect.Dx())/2, qrRect.Dy()+20,
combinedRect.Max.X, combinedRect.Max.Y)
draw.Draw(combinedImg, target, &scaledTextImg, scaledTextRect.Min, draw.Src)
return combinedImg
}
var tmpl = template.Must(template.New("form").Parse(`
<!DOCTYPE html>
<html><body>
<table><tr>
<td valign=top>
<img border=1 src='?img&amp;width={{.Width}}&amp;text={{.Text}}'>
</td>
<td valign=top>
<form><fieldset>
<p><label for=width>Tape width in pt:</label>
<input id=width name=width value='{{.Width}}'>
<p><label for=text>Text:</label>
<input id=text name=text value='{{.Text}}'>
<p><input type=submit value='Update'>
<input type=submit name=print value='Update and Print'>
</fieldset></form>
</td>
</tr></table>
</body></html>
`))
func handle(w http.ResponseWriter, r *http.Request) {
if err := r.ParseForm(); err != nil {
http.Error(w, err.Error(), 500)
return
}
var params = struct {
Width int
Text string
}{
Text: r.FormValue("text"),
}
var err error
params.Width, err = strconv.Atoi(r.FormValue("width"))
if err != nil {
params.Width = 306 // Default to 29mm tape.
}
// TODO: Possibly just remove the for-width mode.
label := genLabel(params.Text, params.Width)
label = &leftRotate{image: genLabelForHeight(params.Text, params.Width)}
if r.FormValue("print") != "" {
if err := printLabel(label); err != nil {
log.Println("print error:", err)
}
}
if _, ok := r.Form["img"]; !ok {
w.Header().Set("Content-Type", "text/html")
tmpl.Execute(w, &params)
return
}
w.Header().Set("Content-Type", "image/png")
if err := png.Encode(w, label); err != nil {
http.Error(w, err.Error(), 500)
return
}
}
func main() {
var err error
fi, err := os.Open("../../ucs-fonts-75dpi100dpi/100dpi/luBS24.bdf")
if err != nil {
log.Fatalln(err)
}
font, err = bdf.NewFromBDF(fi)
if err != nil {
log.Fatalln(err)
}
if err := fi.Close(); err != nil {
log.Fatalln(err)
}
log.Println("Starting server")
http.HandleFunc("/", handle)
log.Fatal(http.ListenAndServe(":8080", nil))
}