package utils

import (
	"regexp"
	"strings"
)

var (
	slugRegex     = regexp.MustCompile(`^[a-z0-9-]+$`)
	reservedSlugs = map[string]bool{
		"admin":      true,
		"api":        true,
		"auth":       true,
		"system":     true,
		"root":       true,
		"super":      true,
		"public":     true,
		"internal":   true,
		"baron":      true,
		"sso":        true,
		"login":      true,
		"logout":     true,
		"signup":     true,
		"register":   true,
		"tenant":     true,
		"user":       true,
		"dev":        true,
		"stage":      true,
		"prod":       true,
		"test":       true,
		"static":     true,
		"assets":     true,
		"image":      true,
		"img":        true,
		"mail":       true,
		"smtp":       true,
		"pop":        true,
		"imap":       true,
		"ns":         true,
		"mx":         true,
		"webmaster":  true,
		"security":   true,
		"support":    true,
		"help":       true,
		"billing":    true,
		"account":    true,
		"config":     true,
		"status":     true,
		"health":     true,
		"metrics":    true,
		"grafana":    true,
		"prometheus": true,
	}
)

// ValidateSlug checks if a slug meets requirements and is not reserved.
func ValidateSlug(slug string) (bool, string) {
	s := strings.ToLower(strings.TrimSpace(slug))

	if len(s) < 3 || len(s) > 32 {
		return false, "slug must be between 3 and 32 characters"
	}

	if !slugRegex.MatchString(s) {
		return false, "slug can only contain lowercase letters, numbers, and hyphens"
	}

	if strings.HasPrefix(s, "-") || strings.HasSuffix(s, "-") {
		return false, "slug cannot start or end with a hyphen"
	}

	if reservedSlugs[s] {
		return false, "slug is a reserved keyword"
	}

	return true, ""
}