cmd/tui: Use own asker implementation

This allows influencing the error caused on wrong inputs.
To stay consistent with the other tui errors we cannot use LXD's asker as we cannot modify the yielded error.

Signed-off-by: Julian Pelizäus <julian.pelizaeus@canonical.com>

Author: roosterfish

cmd/tui/handler.go

@@ -4,16 +4,19 @@ import (
 	"bufio"
 	"fmt"
 	"os"
+	"slices"
 	"strings"
 	"sync"
 
-	"github.com/canonical/lxd/shared/cmd"
 	tea "github.com/charmbracelet/bubbletea"
 )
 
 // ContextError is the charmbracelet representation of a context cancellation error.
 var ContextError error = tea.ErrProgramKilled
 
+// InvalidInputError is used to indicate false input to an asked question.
+var InvalidInputError func() = func() { PrintError("Invalid input, try again") }
+
 // InputHandler handles input dialogs.
 type InputHandler struct {
 	input  *os.File
@@ -73,6 +76,24 @@ func (i *InputHandler) formatQuestion(question string, defaultAnswer string, acc
 	return fmt.Sprintf("%s%s%s: ", question, acceptedAnswersBlock, defaultAnswerBlock)
 }
 
+// Ask a question on the output stream and read the answer from the input stream.
+func (i *InputHandler) askQuestion(question, defaultAnswer string) (string, error) {
+	fmt.Print(question)
+
+	return i.readAnswer(defaultAnswer)
+}
+
+// Read the user's answer from the input stream, trimming newline and providing a default.
+func (i *InputHandler) readAnswer(defaultAnswer string) (string, error) {
+	answer, err := bufio.NewReader(i.input).ReadString('\n')
+	answer = strings.TrimSpace(strings.TrimSuffix(answer, "\n"))
+	if answer == "" {
+		answer = defaultAnswer
+	}
+
+	return answer, err
+}
+
 // AskBoolWarn is the same as AskBool but it prints the given warning before asking.
 func (i *InputHandler) AskBoolWarn(warning string, question string, defaultAnswer bool) (bool, error) {
 	PrintWarning(warning)
@@ -88,8 +109,20 @@ func (i *InputHandler) AskBool(question string, defaultAnswer bool) (bool, error
 		defaultAnswerStr = "yes"
 	}
 
-	asker := cmd.NewAsker(bufio.NewReader(i.input), nil)
-	return asker.AskBool(i.formatQuestion(question, defaultAnswerStr, []string{"yes", "no"}), defaultAnswerStr)
+	for {
+		answer, err := i.askQuestion(i.formatQuestion(question, defaultAnswerStr, []string{"yes", "no"}), defaultAnswerStr)
+		if err != nil {
+			return false, err
+		}
+
+		if slices.Contains([]string{"yes", "y"}, strings.ToLower(answer)) {
+			return true, nil
+		} else if slices.Contains([]string{"no", "n"}, strings.ToLower(answer)) {
+			return false, nil
+		}
+
+		InvalidInputError()
+	}
 }
 
 // AskStringWarn is the same as AskString but it prints the given warning before asking.
@@ -103,11 +136,26 @@ func (i *InputHandler) AskString(question string, defaultAnswer string, validato
 	i.setActive(true)
 	defer i.setActive(false)
 
-	asker := cmd.NewAsker(bufio.NewReader(i.input), nil)
-	result, err := asker.AskString(i.formatQuestion(question, defaultAnswer, nil), defaultAnswer, validator)
-	if err != nil {
-		return "", err
-	}
+	for {
+		answer, err := i.askQuestion(i.formatQuestion(question, defaultAnswer, nil), defaultAnswer)
+		if err != nil {
+			return "", err
+		}
 
-	return result, nil
+		if validator != nil {
+			err = validator(answer)
+			if err != nil {
+				InvalidInputError()
+				continue
+			}
+
+			return answer, err
+		}
+
+		if len(answer) != 0 {
+			return answer, err
+		}
+
+		InvalidInputError()
+	}
 }