setup input

main.go

@@ -25,7 +25,9 @@ import (
 	"unicode/utf8"
 
 	tea "github.com/charmbracelet/bubbletea"
+	"github.com/mattn/go-runewidth"
 	"github.com/pelletier/go-toml/v2"
+	"golang.org/x/term"
 )
 
 var (
@@ -314,9 +316,8 @@ func generateServiceName() string {
 }
 
 func promptServiceName(defaultName string) (string, error) {
-	reader := bufio.NewReader(os.Stdin)
-	fmt.Printf("%sService name%s [%s]: ", headerColor, remoteColorReset, defaultName)
-	input, err := reader.ReadString('\n')
+	prompt := fmt.Sprintf("%sService name%s [%s]: ", headerColor, remoteColorReset, defaultName)
+	input, err := readEditableLine(prompt)
 	if err != nil {
 		return "", err
 	}
@@ -368,13 +369,12 @@ func confirmServerConfig(pbPath string) error {
 	}
 
 	fmt.Printf("Confirm remote server settings (press Enter to keep the current value):\n")
-	reader := bufio.NewReader(os.Stdin)
 
 	ipDefault := cfg.Server.IP
 	if ipDefault == "" {
 		ipDefault = "127.0.0.1"
 	}
-	ip, err := promptWithDefault(reader, "Server IP", ipDefault)
+	ip, err := promptWithDefault("Server IP", ipDefault)
 	if err != nil {
 		return err
 	}
@@ -383,7 +383,7 @@ func confirmServerConfig(pbPath string) error {
 	if portDefault <= 0 {
 		portDefault = 8090
 	}
-	port, err := promptPort(reader, "Server port", portDefault)
+	port, err := promptPort("Server port", portDefault)
 	if err != nil {
 		return err
 	}
@@ -392,7 +392,7 @@ func confirmServerConfig(pbPath string) error {
 	if domainDefault == "" {
 		domainDefault = "example.com"
 	}
-	domain, err := promptWithDefault(reader, "Server domain", domainDefault)
+	domain, err := promptWithDefault("Server domain", domainDefault)
 	if err != nil {
 		return err
 	}
@@ -407,15 +407,15 @@ func confirmServerConfig(pbPath string) error {
 	return nil
 }
 
-func promptWithDefault(reader *bufio.Reader, label, defaultValue string) (string, error) {
-	fmt.Printf("%s%s%s", headerColor, label, remoteColorReset)
+func promptWithDefault(label, defaultValue string) (string, error) {
+	var suffix string
 	if defaultValue != "" {
-		fmt.Printf(" [%s]: ", defaultValue)
+		suffix = fmt.Sprintf(" [%s]: ", defaultValue)
 	} else {
-		fmt.Print(": ")
+		suffix = ": "
 	}
-
-	input, err := reader.ReadString('\n')
+	prompt := fmt.Sprintf("%s%s%s%s", headerColor, label, remoteColorReset, suffix)
+	input, err := readEditableLine(prompt)
 	if err != nil {
 		return "", err
 	}
@@ -427,14 +427,14 @@ func promptWithDefault(reader *bufio.Reader, label, defaultValue string) (string
 	return input, nil
 }
 
-func promptPort(reader *bufio.Reader, label string, defaultValue int) (int, error) {
+func promptPort(label string, defaultValue int) (int, error) {
 	if defaultValue <= 0 {
 		defaultValue = 8090
 	}
 
 	for {
-		fmt.Printf("%s%s%s [%d]: ", headerColor, label, remoteColorReset, defaultValue)
-		input, err := reader.ReadString('\n')
+		prompt := fmt.Sprintf("%s%s%s [%d]: ", headerColor, label, remoteColorReset, defaultValue)
+		input, err := readEditableLine(prompt)
 		if err != nil {
 			return 0, err
 		}
@@ -463,31 +463,20 @@ func normalizePromptInput(raw string) string {
 			break
 		}
 		if r == 0x1b {
-			nextIndex := i + size
-			if nextIndex >= len(raw) {
-				break
+			nextIndex, final := skipEscapeSequence(raw, i)
+			if nextIndex <= i {
+				i++
+				continue
 			}
-			next, nextSize := utf8.DecodeRuneInString(raw[nextIndex:])
-			if next == 0x7f || next == 0x08 {
+			i = nextIndex
+			if final == 0x7f || final == 0x08 {
 				buf = deletePreviousWord(buf)
-				i = nextIndex + nextSize
-				continue
 			}
-			if next == '[' || next == 'O' {
-				i = nextIndex + nextSize
-				for i < len(raw) {
-					code, codeSize := utf8.DecodeRuneInString(raw[i:])
-					if codeSize == 0 {
-						break
-					}
-					i += codeSize
-					if ('A' <= code && code <= 'Z') || ('a' <= code && code <= 'z') {
-						break
-					}
-				}
-				continue
-			}
-			i = nextIndex + nextSize
+			continue
+		}
+		if r == 0x17 {
+			buf = deletePreviousWord(buf)
+			i += size
 			continue
 		}
 		if r == 0x7f || r == 0x08 {
@@ -503,6 +492,132 @@ func normalizePromptInput(raw string) string {
 	return string(buf)
 }
 
+func readEditableLine(prompt string) (string, error) {
+	fd := int(os.Stdin.Fd())
+	reader := bufio.NewReader(os.Stdin)
+	if !term.IsTerminal(fd) {
+		line, err := reader.ReadString('\n')
+		if err != nil {
+			return "", err
+		}
+		line = strings.TrimRight(line, "\r\n")
+		return line, nil
+	}
+
+	oldState, err := term.MakeRaw(fd)
+	if err != nil {
+		return "", err
+	}
+	defer term.Restore(fd, oldState)
+
+	var buf []rune
+	var lastWidth int
+	fmt.Print(prompt)
+
+	for {
+		r, _, err := reader.ReadRune()
+		if err != nil {
+			return "", err
+		}
+
+		switch {
+		case r == '\r' || r == '\n':
+			fmt.Println()
+			return string(buf), nil
+		case r == 0x03:
+			fmt.Println()
+			return "", errors.New("input interrupted")
+		case r == 0x04:
+			fmt.Println()
+			return "", io.EOF
+		case r == 0x7f || r == 0x08:
+			if len(buf) > 0 {
+				buf = buf[:len(buf)-1]
+				redrawEditableLine(prompt, buf, &lastWidth)
+			}
+		case r == 0x17:
+			buf = deletePreviousWord(buf)
+			redrawEditableLine(prompt, buf, &lastWidth)
+		case r == 0x1b:
+			final, err := readEscapeFinal(reader)
+			if err != nil {
+				return "", err
+			}
+			if final == 0x7f || final == 0x08 {
+				buf = deletePreviousWord(buf)
+				redrawEditableLine(prompt, buf, &lastWidth)
+			}
+		default:
+			if r < 0x20 {
+				continue
+			}
+			buf = append(buf, r)
+			redrawEditableLine(prompt, buf, &lastWidth)
+		}
+	}
+}
+
+func readEscapeFinal(reader *bufio.Reader) (rune, error) {
+	b, err := reader.ReadByte()
+	if err != nil {
+		return 0, err
+	}
+	if b == '[' || b == 'O' {
+		for {
+			c, err := reader.ReadByte()
+			if err != nil {
+				return 0, err
+			}
+			if isCSIFinalByte(rune(c)) {
+				return rune(c), nil
+			}
+		}
+	}
+	return rune(b), nil
+}
+
+func redrawEditableLine(prompt string, buf []rune, lastWidth *int) {
+	fmt.Print("\r")
+	fmt.Print(prompt)
+	text := string(buf)
+	fmt.Print(text)
+	width := runewidth.StringWidth(text)
+	if *lastWidth > width {
+		fmt.Print(strings.Repeat(" ", *lastWidth-width))
+		fmt.Print("\r")
+		fmt.Print(prompt)
+		fmt.Print(text)
+	}
+	*lastWidth = width
+}
+
+func skipEscapeSequence(raw string, escIndex int) (int, rune) {
+	i := escIndex + 1
+	if i >= len(raw) {
+		return i, 0
+	}
+	next, size := utf8.DecodeRuneInString(raw[i:])
+	i += size
+	if next == '[' || next == 'O' {
+		for i < len(raw) {
+			code, codeSize := utf8.DecodeRuneInString(raw[i:])
+			if codeSize == 0 {
+				break
+			}
+			i += codeSize
+			if isCSIFinalByte(code) {
+				return i, code
+			}
+		}
+		return i, 0
+	}
+	return i, next
+}
+
+func isCSIFinalByte(r rune) bool {
+	return 0x40 <= r && r <= 0x7e
+}
+
 func deletePreviousWord(buf []rune) []rune {
 	i := len(buf)
 	for i > 0 && unicode.IsSpace(buf[i-1]) {