feat: huge overhaul of messaging into FAIL, WARN, hint, ok, prompt, and progress types

cmd/msg.go

@@ -0,0 +1,95 @@
+package cmd
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+
+	"golang.org/x/term"
+)
+
+// hinted wraps an error with an actionable hint shown on a separate line.
+type hinted struct {
+	err  error
+	hint string
+}
+
+func (h hinted) Error() string { return h.err.Error() }
+func (h hinted) Unwrap() error { return h.err }
+
+func withHint(err error, hint string) error {
+	return hinted{err: err, hint: hint}
+}
+
+func stderrIsTerminal() bool {
+	return term.IsTerminal(int(os.Stderr.Fd()))
+}
+
+func stdoutIsTerminal() bool {
+	return term.IsTerminal(int(os.Stdout.Fd()))
+}
+
+// keyword returns a right-aligned, colored keyword (color only on TTY).
+//
+//	FAIL  red         (stderr)
+//	hint  dim         (stderr)
+//	WARN  yellow      (stderr)
+//	  ok  green       (stderr)
+//	   ?  cyan        (stdout)
+//	   >  dim         (stdout)
+func keyword(code, word string, tty bool) string {
+	padded := fmt.Sprintf("%4s", word)
+	if tty {
+		return fmt.Sprintf("\033[%sm%s\033[0m", code, padded)
+	}
+	return padded
+}
+
+func printError(err error) {
+	fmt.Fprintf(os.Stderr, "%s  %s\n", keyword("31", "FAIL", stderrIsTerminal()), err)
+}
+
+func printHint(format string, args ...any) {
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(os.Stderr, "%s  %s\n", keyword("2", "hint", stderrIsTerminal()), msg)
+}
+
+func warnf(format string, args ...any) {
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(os.Stderr, "%s  %s\n", keyword("33", "WARN", stderrIsTerminal()), msg)
+}
+
+func okf(format string, args ...any) {
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(os.Stderr, "%s  %s\n", keyword("32", "ok", stderrIsTerminal()), msg)
+}
+
+func promptf(format string, args ...any) {
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(os.Stdout, "%s  %s\n", keyword("36", "???", stdoutIsTerminal()), msg)
+}
+
+func progressf(format string, args ...any) {
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(os.Stdout, "%s  %s\n", keyword("2", ">", stdoutIsTerminal()), msg)
+}
+
+func scanln(dest *string) error {
+	fmt.Fprintf(os.Stdout, "%s  ", keyword("2", "==>", stdoutIsTerminal()))
+	_, err := fmt.Scanln(dest)
+	return err
+}
+
+// printErrorWithHints prints the error and any hints found in the error chain.
+func printErrorWithHints(err error) {
+	printError(err)
+	var h hinted
+	if errors.As(err, &h) {
+		printHint("%s", h.hint)
+	}
+	var nf errNotFound
+	if errors.As(err, &nf) && len(nf.suggestions) > 0 {
+		printHint("did you mean '%s'?", strings.Join(nf.suggestions, "', '"))
+	}
+}