1package stringext
 2
 3import (
 4	"encoding/base64"
 5	"strings"
 6
 7	"golang.org/x/text/cases"
 8	"golang.org/x/text/language"
 9)
10
11func Capitalize(text string) string {
12	return cases.Title(language.English, cases.Compact).String(text)
13}
14
15// NormalizeSpace normalizes whitespace in the given content string.
16// It replaces Windows-style line endings with Unix-style line endings,
17// converts tabs to four spaces, and trims leading and trailing whitespace.
18func NormalizeSpace(content string) string {
19	content = strings.ReplaceAll(content, "\r\n", "\n")
20	content = strings.ReplaceAll(content, "\t", "    ")
21	content = strings.TrimSpace(content)
22	return content
23}
24
25// IsValidBase64 reports whether s is canonical base64 under standard
26// encoding (RFC 4648). It requires that s round-trips through
27// decode/encode unchanged — rejecting whitespace, missing padding,
28// and other leniencies that DecodeString alone would accept.
29func IsValidBase64(s string) bool {
30	if s == "" {
31		return false
32	}
33	decoded, err := base64.StdEncoding.DecodeString(s)
34	if err != nil {
35		return false
36	}
37	// Round-trip check rejects whitespace, missing padding, and other
38	// leniencies that DecodeString silently accepts.
39	return base64.StdEncoding.EncodeToString(decoded) == s
40}