package redactutil

import (
	"fmt"
	"regexp"
	"strings"
)

func NormalizeMask(mask string) string {
	mask = strings.TrimSpace(mask)
	if mask == "" {
		return "[REDACTED]"
	}
	return mask
}

func BuildFieldSet(fields ...string) map[string]struct{} {
	fieldMap := make(map[string]struct{}, len(fields))
	for _, field := range fields {
		field = strings.TrimSpace(strings.ToLower(field))
		if field == "" {
			continue
		}
		fieldMap[field] = struct{}{}
	}
	return fieldMap
}

func LookupFieldKey(key string) string {
	return strings.TrimSpace(strings.ToLower(key))
}

func MaskFields(fields map[string]interface{}, mask string) map[string]interface{} {
	if len(fields) == 0 {
		return nil
	}
	mask = NormalizeMask(mask)
	masked := make(map[string]interface{}, len(fields))
	for key := range fields {
		masked[key] = mask
	}
	return masked
}

func ReplaceRegex(pattern *regexp.Regexp, text string, replacement string) (string, bool) {
	if pattern == nil || text == "" {
		return text, false
	}
	if replacement == "" {
		replacement = "[REDACTED]"
	}
	changed := pattern.ReplaceAllString(text, replacement)
	return changed, changed != text
}

func IsMasked(value interface{}, mask string) bool {
	return fmt.Sprint(value) == mask
}