Initial Commit

cmd/wasm/main.go

@@ -0,0 +1,118 @@
+package main
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"syscall/js"
+
+	"github.com/thegrumpylion/jsref"
+
+	"covergen/pkg/covergen"
+)
+
+type jsmap = map[string]interface{}
+
+type covergenArgs struct {
+	Customer     string `jsref:"customer"`
+	Number       string `jsref:"number"`
+	NumberPrefix string `jsref:"numberPrefix"`
+	HLColor      string `jsref:"hlColor"`
+}
+
+func parseHexColor(s string) (c covergen.Color, err error) {
+	switch len(s) {
+	case 7:
+		_, err = fmt.Sscanf(s, "#%02x%02x%02x", &c.R, &c.G, &c.B)
+	case 4:
+		_, err = fmt.Sscanf(s, "#%1x%1x%1x", &c.R, &c.G, &c.B)
+		// Double the hex digits:
+		c.R *= 17
+		c.G *= 17
+		c.B *= 17
+	default:
+		err = fmt.Errorf("invalid length, must be 7 or 4")
+
+	}
+	return
+}
+
+func settingsFromValue(arg js.Value) (*covergen.CoverSettings, error) {
+	settings := covergenArgs{
+		NumberPrefix: "offerte",
+	}
+	err := jsref.Unmarshal(&settings, arg)
+	if err != nil {
+		return nil, err
+	}
+
+	if settings.Number == "" {
+		return nil, errors.New("number: shouldn't be empty")
+	}
+
+	if settings.Customer == "" {
+		return nil, errors.New("customer: shouldn't be empty")
+	}
+
+	color := covergen.Color{R: 255}
+	if settings.HLColor != "" {
+		color, err = parseHexColor(settings.HLColor)
+		if err != nil {
+			return nil, fmt.Errorf("hlColor: %w", err)
+		}
+	}
+
+	return &covergen.CoverSettings{
+		Number:       settings.Number,
+		NumberPrefix: settings.NumberPrefix,
+		CustomerName: settings.Customer,
+		HLColor:      color,
+	}, nil
+}
+
+func generateCover(this js.Value, args []js.Value) interface{} {
+	defer func() {
+		if r := recover(); r != nil {
+			fmt.Println("recovered", r)
+		}
+	}()
+
+	if len(args) != 1 {
+		return jsmap{"error": "missing argument"}
+	}
+
+	arg := args[0]
+	if arg.Type() != js.TypeObject {
+		return jsmap{"error": "expected object"}
+	}
+
+	settings, err := settingsFromValue(arg)
+	if err != nil {
+		return jsmap{"error": err.Error()}
+	}
+
+	pdf, err := covergen.GenerateInvoice(*settings)
+	if err != nil {
+		return jsmap{"error": err.Error()}
+	}
+
+	var buf bytes.Buffer
+	if err = pdf.Output(&buf); err != nil {
+		return jsmap{"error": err.Error()}
+	}
+
+	s := buf.Bytes()
+	sum := sha256.Sum256(s)
+	fmt.Println("shasum", hex.EncodeToString(sum[:]))
+
+	ta := js.Global().Get("Uint8Array").New(len(s))
+	js.CopyBytesToJS(ta, s)
+	return ta
+}
+
+func main() {
+	js.Global().Set("covergen", js.FuncOf(generateCover))
+	<-make(chan bool)
+}