Fix prompt indicator

We only support Unix like systems for colors and windows gets the color
information removed to reduce the output clutter.

README.md

@@ -7,6 +7,8 @@ This is a fork from [itzg/rcon-cli](https://github.com/itzg/rcon-cli) with follo
 - Remove `config.yml` support.
 - Change the `Dockerfile` to have build support.
 
+Note: *This tool is primarily being maintained to support minecraft RCON implementation.*
+
 ## Installation
 ### From Source
 Clone the repository and install it with `go install` (requires working `go` installation)
@@ -40,3 +42,7 @@ EXAMPLES:
 	rcon-cli --password admin123 stop
 	RCON_CLI_PORT=25575 rcon-cli stop
 ```
+
+## LICENSE
+
+The software is licensed under the [Apache-2.0](LICENSE) license.

main.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"net"
 	"os"
+	"runtime"
 	"strings"
 
 	"github.com/hamburghammer/rcon"
@@ -21,6 +22,35 @@ const (
 	envVarPrefix = "RCON_CLI_"
 )
 
+// resetColor is the ASCII code for resetting the color.
+const resetColor = "\u001B[0m"
+
+// colors a map with the ASCII color codes for Unix terms.
+var colors = map[string]string{
+	"0": "\u001B[30m", // black
+	"1": "\u001B[34m", // dark blue
+	"2": "\u001B[32m", // dark green
+	"3": "\u001B[36m", // dark aqua
+	"4": "\u001B[31m", // dark red
+	"5": "\u001B[35m", // dark purple
+	"6": "\u001B[33m", // gold
+	"7": "\u001B[37m", // gray
+	"8": "\u001B[30m", // dark gray
+	"9": "\u001B[34m", // blue
+	"a": "\u001B[32m", // green
+	"b": "\u001B[32m", // aqua
+	"c": "\u001B[31m", // red
+	"d": "\u001B[35m", // light purple
+	"e": "\u001B[33m", // yellow
+	"f": "\u001B[37m", // white
+	"k": "",           // random
+	"m": "\u001B[9m",  // strikethrough
+	"o": "\u001B[3m",  // italic
+	"l": "\u001B[1m",  // bold
+	"n": "\u001B[4m",  // underline
+	"r": resetColor,   // reset
+}
+
 // vars holding the parsed configuration
 var (
 	host     string
@@ -40,7 +70,10 @@ func main() {
 
 	err := run(strings.Join(commands, " "))
 	if err != nil {
-		fmt.Fprintln(os.Stderr, err.Error())
+		_, err = fmt.Fprintln(os.Stderr, err.Error())
+		if err != nil {
+			panic(err)
+		}
 		os.Exit(1)
 	}
 }
@@ -93,14 +126,14 @@ func run(cmd string) error {
 		if err != nil {
 			return err
 		}
-		fmt.Println(resp)
+		_, err = fmt.Println(resp)
 	}
 
 	return err
 }
 
 func printHelp() {
-	fmt.Println(`rcon-cli is a CLI to interact with a RCON server.
+	_, _ = fmt.Println(`rcon-cli is a CLI to interact with a RCON server.
 It can be run in an interactive mode or to execute a single command.
 
 USAGE:
@@ -122,9 +155,9 @@ EXAMPLES:
 
 func executeInteractive(remoteConsole *rcon.RemoteConsole) error {
 	scanner := bufio.NewScanner(os.Stdin)
-	fmt.Println("To quit the session type 'exit'.")
+	_, _ = fmt.Println("To quit the session type 'exit'.")
+	_, _ = fmt.Print("> ")
 	for scanner.Scan() {
-		fmt.Print("> ")
 		cmd := scanner.Text()
 		if cmd == "exit" {
 			return nil
@@ -134,7 +167,8 @@ func executeInteractive(remoteConsole *rcon.RemoteConsole) error {
 			return err
 		}
 
-		fmt.Println(resp)
+		_, _ = fmt.Println(resp)
+		_, _ = fmt.Print("> ")
 	}
 
 	if err := scanner.Err(); err != nil {
@@ -163,5 +197,27 @@ func execute(cmd string, remoteConsole *rcon.RemoteConsole) (string, error) {
 		return resp, errors.New("the response id didn't match the request id")
 	}
 
+	resp = colorize(resp)
+
 	return resp, nil
 }
+
+// colorize tries to add the color codes for the terminal.
+// works on none windows machines.
+func colorize(str string) string {
+	const sectionSign = "§"
+
+	for code := range colors {
+		if runtime.GOOS == "windows" {
+			str = strings.ReplaceAll(str, sectionSign+code, "")
+		} else {
+			str = strings.ReplaceAll(str, sectionSign+code, colors[code])
+		}
+	}
+	// reset color after each new line
+	if runtime.GOOS != "windows" {
+		return strings.ReplaceAll(str, "\n", "\n"+resetColor)
+	}
+
+	return str
+}