Add hex2bin tool and improve output file naming logic

.gitignore

@@ -1,3 +1,4 @@
+opt/
 # If you prefer the allow list template instead of the deny list, see community template:
 # https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
 #

converter/converter.go

@@ -113,19 +113,43 @@ func IntelHexToBin(inputFile string, outputFile string) error {
 		return fmt.Errorf("no data segments found in Intel HEX file")
 	}
 
+	// Find the lowest and highest addresses
+	minAddr := segments[0].Address
+	maxAddr := segments[0].Address + uint32(len(segments[0].Data))
+	for _, segment := range segments {
+		if segment.Address < minAddr {
+			minAddr = segment.Address
+		}
+		endAddr := segment.Address + uint32(len(segment.Data))
+		if endAddr > maxAddr {
+			maxAddr = endAddr
+		}
+	}
+
+	// Create a buffer filled with 0xFF
+	totalLen := maxAddr - minAddr
+	binData := make([]byte, totalLen)
+	for i := range binData {
+		binData[i] = 0xFF
+	}
+
+	// Copy each segment's data into the buffer
+	for _, segment := range segments {
+		start := segment.Address - minAddr
+		copy(binData[start:start+uint32(len(segment.Data))], segment.Data)
+	}
+
 	// Create output file
-	ofw, err := os.Create(outputFile)
+	of, err := os.Create(outputFile)
 	if err != nil {
 		return fmt.Errorf("error creating output file: %w", err)
 	}
-	defer ofw.Close()
+	defer of.Close()
 
-	// Write binary data in order of addresses
-	for _, segment := range segments {
-		_, err = ofw.Write(segment.Data)
-		if err != nil {
-			return fmt.Errorf("error writing binary data: %v", err)
-		}
+	// Write the buffer to the file
+	_, err = of.Write(binData)
+	if err != nil {
+		return fmt.Errorf("error writing binary data: %v", err)
 	}
 
 	return nil

main.go

@@ -14,8 +14,8 @@ var (
 	buildTime = "unknown"
 )
 
-// getOutputFileName determines the output file name based on input file and mode
-func getOutputFileName(inputFile, mode string) (string, error) {
+// GetOutputFileName determines the output file name based on input file and mode
+func GetOutputFileName(inputFile, mode string) (string, error) {
 	ext := ""
 	switch mode {
 	case "bin2hex":
@@ -26,7 +26,22 @@ func getOutputFileName(inputFile, mode string) (string, error) {
 		return "", fmt.Errorf("cannot determine output file extension for mode '%s' (should be 'bin2hex' or 'hex2bin')", mode)
 	}
 	base := strings.TrimSuffix(inputFile, filepath.Ext(inputFile))
-	return base + ext, nil
+	output := base + ext
+
+	// Add suffix if file exists
+	if _, err := os.Stat(output); err == nil {
+		suffix := 1
+		for {
+			candidate := fmt.Sprintf("%s_%d%s", base, suffix, ext)
+			if _, err := os.Stat(candidate); os.IsNotExist(err) {
+				output = candidate
+				break
+			}
+			suffix++
+		}
+	}
+
+	return output, nil
 }
 
 // getModeFromInputExt tries to determine the mode from the input file extension
@@ -64,7 +79,7 @@ func main() {
 		if arg == "bin2hex" || arg == "hex2bin" {
 			mode = arg
 			var err error
-			outputFile, err = getOutputFileName(inputFile, mode)
+			outputFile, err = GetOutputFileName(inputFile, mode)
 			if err != nil {
 				fmt.Printf("Error: %v\n", err)
 				os.Exit(1)
@@ -86,7 +101,7 @@ func main() {
 			fmt.Printf("Error: %v\n", err)
 			os.Exit(1)
 		}
-		outputFile, err = getOutputFileName(inputFile, mode)
+		outputFile, err = GetOutputFileName(inputFile, mode)
 		if err != nil {
 			fmt.Printf("Error: %v\n", err)
 			os.Exit(1)

main_test.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestGetOutputFileName_NoConflict(t *testing.T) {
+	dir := t.TempDir()
+	input := filepath.Join(dir, "file.hex")
+	os.WriteFile(input, []byte("dummy"), 0644)
+	name, err := GetOutputFileName(input, "hex2bin")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if filepath.Base(name) != "file.bin" {
+		t.Errorf("expected file.bin, got %s", filepath.Base(name))
+	}
+}
+
+func TestGetOutputFileName_OneConflict(t *testing.T) {
+	dir := t.TempDir()
+	input := filepath.Join(dir, "file.hex")
+	os.WriteFile(input, []byte("dummy"), 0644)
+	os.WriteFile(filepath.Join(dir, "file.bin"), []byte("bin"), 0644)
+	name, err := GetOutputFileName(input, "hex2bin")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if filepath.Base(name) != "file_1.bin" {
+		t.Errorf("expected file_1.bin, got %s", filepath.Base(name))
+	}
+}
+
+func TestGetOutputFileName_MultipleConflicts(t *testing.T) {
+	dir := t.TempDir()
+	input := filepath.Join(dir, "file.hex")
+	os.WriteFile(input, []byte("dummy"), 0644)
+	os.WriteFile(filepath.Join(dir, "file.bin"), []byte("bin"), 0644)
+	os.WriteFile(filepath.Join(dir, "file_1.bin"), []byte("bin1"), 0644)
+	os.WriteFile(filepath.Join(dir, "file_2.bin"), []byte("bin2"), 0644)
+	name, err := GetOutputFileName(input, "hex2bin")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if filepath.Base(name) != "file_3.bin" {
+		t.Errorf("expected file_3.bin, got %s", filepath.Base(name))
+	}
+}