cli: move input handling to a separate package

cli/input/input.go

@@ -0,0 +1,44 @@
+package input
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+	"syscall"
+
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+// Terminal is a terminal used for input. If `nil`, stdin is used.
+var Terminal *terminal.Terminal
+
+// ReadLine reads line from the input without trailing '\n'
+func ReadLine(w io.Writer, prompt string) (string, error) {
+	if Terminal != nil {
+		_, err := Terminal.Write([]byte(prompt))
+		if err != nil {
+			return "", err
+		}
+		raw, err := Terminal.ReadLine()
+		return strings.TrimRight(raw, "\n"), err
+	}
+	fmt.Fprint(w, prompt)
+	buf := bufio.NewReader(os.Stdin)
+	return buf.ReadString('\n')
+}
+
+// ReadPassword reads user password with prompt.
+func ReadPassword(w io.Writer, prompt string) (string, error) {
+	if Terminal != nil {
+		return Terminal.ReadPassword(prompt)
+	}
+	fmt.Fprint(w, prompt)
+	rawPass, err := terminal.ReadPassword(syscall.Stdin)
+	if err != nil {
+		return "", err
+	}
+	fmt.Fprintln(w)
+	return strings.TrimRight(string(rawPass), "\n"), nil
+}