add template functions

.gitignore

@@ -29,3 +29,4 @@ build
 assets
 libgofunc
 libgo
+cmd/out.png

build_lib.sh

@@ -1,9 +1,9 @@
 #!/bin/bash
 
 APP_NAME="libgofunc"
-VERSION="${1:-v0.1.3}"
+VERSION="${1:-v0.1.5}"
-OUTPUT_DIR="assets"
+OUTPUT_DIR="../assets"
-BUILD_DIR="build"
+BUILD_DIR="../build"
 
 # need Android NDK
 NDK_HOME="$HOME/Android/Sdk/ndk/28.2.13676358" # <--- CHECK YOUR VERSION
@@ -11,7 +11,7 @@ API=21
 
 TOOLCHAIN="$NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin"
 OS="$(uname -s)"
-
+cd cmd
 if [ "$OS" = "Darwin" ]; then
     export IOS_SDK=$(xcrun --sdk iphoneos --show-sdk-path)
     export IOS_SIM_SDK=$(xcrun --sdk iphonesimulator --show-sdk-path)
@@ -27,7 +27,7 @@ if [ "$OS" = "Darwin" ]; then
     CC="$(xcrun --sdk iphonesimulator --find clang)" \
     CGO_CFLAGS="-isysroot $IOS_SIM_SDK -arch x86_64" \
     CGO_LDFLAGS="-isysroot $IOS_SIM_SDK -arch x86_64" \
-    go build -buildmode=c-archive -o build/ios/sim/libgofunc_arm64_sim.a .
+    go build ./cmd -buildmode=c-archive -o build/ios/sim/libgofunc_arm64_sim.a .
 
     # xcodebuild -create-xcframework \
     # -library build/ios/device/libgofunc_arm64.a -headers build/ios/device/ \
@@ -74,7 +74,7 @@ elif [ "$OS" = "Linux" ]; then
     tar -czf "${OUTPUT_DIR}/${VERSION}/${ARCHIVE_NAME}" -C "${BUILD_DIR}" ./${VERSION}/${ARCH}
 
     export HTTPS_PROXY="socks5://localhost:8080"
-    rclone copy ./assets/${VERSION} s3:mokkon/libs/libgofunc/${VERSION}
+    rclone copy ../assets/${VERSION} s3:mokkon/libs/libgofunc/${VERSION}
 else
     echo "Unsupported OS: $OS"
     exit 1

go.sum

@@ -4,8 +4,6 @@ github.com/fogleman/gg v1.3.0 h1:/7zJX8F6AaYQc57WQCyN9cAIz+4bCJGO9B+dyW29am8=
 github.com/fogleman/gg v1.3.0/go.mod h1:R/bRT+9gY/C5z7JzPU0zXsXHKM4/ayA+zqcVNZzPa1k=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k=
-github.com/google/gousb v1.1.3 h1:xt6M5TDsGSZ+rlomz5Si5Hmd/Fvbmo2YCJHN+yGaK4o=
-github.com/google/gousb v1.1.3/go.mod h1:GGWUkK0gAXDzxhwrzetW592aOmkkqSGcj5KLEgmCVUg=
 github.com/kenshaw/escpos v0.0.0-20221114190919-df06b682a8fc h1:4JwmN2Scz1vR+hfSxkdy2IE/DzxX2Cftm2lhWHyN0k0=
 github.com/kenshaw/escpos v0.0.0-20221114190919-df06b682a8fc/go.mod h1:M+GIBmg2MqaSWIJrXCZS+/wRFbr9fOguRz3SHn8DRPE=
 golang.org/x/image v0.38.0 h1:5l+q+Y9JDC7mBOMjo4/aPhMDcxEptsX+Tt3GgRQRPuE=

img.go

@@ -24,7 +24,13 @@ import (
 
 	"github.com/kenshaw/escpos"
 )
-import "log"
+import (
+	"log"
+	"strconv"
+
+	"golang.org/x/text/language"
+	"golang.org/x/text/message"
+)
 
 const (
 	defalutFontSize    = 18.0
@@ -102,8 +108,13 @@ func GenImg(width int, outputPath, payload, tmpl string) string {
 	return r
 }
 
+var funcMap = template.FuncMap{
+	"formatNumber": FormatNumber,
+	"div":          Div,
+}
+
 func renderTemplate(tmp string, data map[string]interface{}) (string, error) {
-	tmpl, err := template.New("mytemplate").Parse(tmp)
+	tmpl, err := template.New("mytemplate").Funcs(funcMap).Parse(tmp)
 	if err != nil {
 		return "", err
 	}
@@ -431,3 +442,66 @@ func nodeHeight(n *html.Node, dc *gg.Context, canvasWidth int, xPadding, yPaddin
 	}
 	return y
 }
+
+type RealNumber interface {
+	~int | ~int8 | ~int16 | ~int32 | ~int64 |
+		~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 |
+		~float32 | ~float64
+}
+
+func FormatNumber(precision int, b any) string {
+	return GenericFormatNumber(precision, convertToFloat64(b))
+}
+
+func GenericFormatNumber[T RealNumber](precision int, v T) string {
+	pEnglish := message.NewPrinter(language.English)
+
+	n := float64(v)
+	s := fmt.Sprintf("%.*f", precision, n)
+
+	parts := strings.Split(s, ".")
+	intPart := parts[0]
+	i, err := strconv.Atoi(intPart)
+	if err != nil {
+		return ""
+	}
+	out := pEnglish.Sprintf("%d", i)
+
+	if len(parts) > 1 {
+		return out + "." + parts[1]
+	}
+	return out
+}
+
+func Div(a, b any) float64 {
+	return GenericDiv(convertToFloat64(a), convertToFloat64(b))
+}
+
+func GenericDiv[T RealNumber](a, b T) float64 {
+	floatB := float64(b)
+	if floatB == 0 {
+		return 0
+	}
+	return float64(a) / floatB
+}
+
+func convertToFloat64(v any) float64 {
+	switch t := v.(type) {
+	case float64:
+		return t
+	case float32:
+		return float64(t)
+	case int:
+		return float64(t)
+	case int64:
+		return float64(t)
+	case int32:
+		return float64(t)
+	case uint:
+		return float64(t)
+	case uint64:
+		return float64(t)
+	default:
+		return 0
+	}
+}

img_test.go

@@ -0,0 +1,60 @@
+package libgofunc
+
+import (
+	"math"
+	"testing"
+)
+
+func TestDiv(t *testing.T) {
+	tests := []struct {
+		name string
+		a    any
+		b    any
+		want float64
+	}{
+		{"Float division", 10.5, 2.0, 5.25},
+		{"Float division", 4975, 1000, 4.975},
+		{"Integer division", 10, 4, 2.5},
+		{"Mixed types", int64(100), float64(4.0), 25.0},
+		{"Division by zero (float)", 10.0, 0.0, 0.0},
+		{"Division by zero (int)", 5, 0, 0.0},
+		{"Unsupported type defaults to zero", "string", 2, 0.0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := Div(tt.a, tt.b)
+			if got != tt.want {
+				t.Errorf("TemplateDiv() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestFormatNumber(t *testing.T) {
+	tests := []struct {
+		name      string
+		precision int
+		val       any
+		want      string
+	}{
+		{"Standard float with commas", 2, 1234567.891, "1,234,567.89"},
+		{"Standard float with commas", 3, 4.975, "4.975"},
+		{"Integer input with commas", 0, 5000000, "5,000,000"},
+		{"Integer input forced decimals", 2, 5000, "5,000.00"},
+		{"Negative float commas", 2, -9876543.21, "-9,876,543.21"},
+		{"Small float rounding up", 2, 0.128, "0.13"},
+		{"Small float rounding down", 2, 0.123, "0.12"},
+		{"Handling NaN", 2, math.NaN(), ""},
+		{"Handling Inf", 2, math.Inf(1), ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := FormatNumber(tt.precision, tt.val)
+			if got != tt.want {
+				t.Errorf("TemplateFloat() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}

printer.go

@@ -17,6 +17,7 @@ import (
 
 	"github.com/kenshaw/escpos"
 )
+import "errors"
 
 //export PrintImg
 func PrintImg(printer *C.char, imagePath *C.char) *C.char {
@@ -77,6 +78,8 @@ func PrintImg(printer *C.char, imagePath *C.char) *C.char {
 		// 	reader := bufio.NewReader(rw)
 		// 	writer := bufio.NewWriter(rw)
 		// 	w = bufio.NewReadWriter(reader, writer)
+	} else {
+		return NewErr(errors.New("invalid printer"))
 	}
 	prt := escpos.New(w)