fix(order): prevent duplicate subscriptions and repair invite gifts

internal/logic/auth/trialEmailWhitelist.go

@@ -2,6 +2,7 @@ package auth
 
 import (
 	"context"
+	"net/mail"
 	"strings"
 
 	"github.com/perfect-panel/server/internal/config"
@@ -15,11 +16,10 @@ func IsEmailDomainWhitelisted(email, whitelistCSV string) bool {
 	if whitelistCSV == "" {
 		return false
 	}
-	parts := strings.SplitN(email, "@", 2)
-	if len(parts) != 2 {
+	_, domain, ok := parseStrictEmail(email)
+	if !ok {
 		return false
 	}
-	domain := strings.ToLower(strings.TrimSpace(parts[1]))
 	for _, d := range strings.Split(whitelistCSV, ",") {
 		if strings.ToLower(strings.TrimSpace(d)) == domain {
 			return true
@@ -32,10 +32,16 @@ func ShouldGrantTrialForEmail(register config.RegisterConfig, email string) bool
 	if !register.EnableTrial {
 		return false
 	}
+	if !IsValidTrialEmail(email) {
+		return false
+	}
 	// 无论白名单是否启用，泛域名邮箱（含 + 别名或 Gmail 点号）始终拒绝赠送
 	if IsDisposableAlias(email) {
 		return false
 	}
+	if isConfusableGmailDomain(emailDomain(email)) {
+		return false
+	}
 	if !register.EnableTrialEmailWhitelist {
 		return true
 	}
@@ -52,11 +58,10 @@ func ShouldGrantTrialForEmail(register config.RegisterConfig, email string) bool
 // For Gmail-like domains, local part containing "." or "+" is rejected.
 // For all other domains, only "+" alias is rejected.
 func IsDisposableAlias(email string) bool {
-	parts := strings.SplitN(strings.ToLower(strings.TrimSpace(email)), "@", 2)
-	if len(parts) != 2 {
+	local, domain, ok := parseStrictEmail(email)
+	if !ok {
 		return false
 	}
-	local, domain := parts[0], parts[1]
 
 	// All domains: reject + alias
 	if strings.ContainsRune(local, '+') {
@@ -74,11 +79,10 @@ func IsDisposableAlias(email string) bool {
 // Removes dots from local part for Gmail-like providers (gmail.com, googlemail.com).
 func NormalizeEmail(email string) string {
 	email = strings.ToLower(strings.TrimSpace(email))
-	parts := strings.SplitN(email, "@", 2)
-	if len(parts) != 2 {
+	local, domain, ok := parseStrictEmail(email)
+	if !ok {
 		return email
 	}
-	local, domain := parts[0], parts[1]
 
 	// Strip + alias
 	if idx := strings.IndexByte(local, '+'); idx != -1 {
@@ -101,6 +105,51 @@ func isGmailLikeDomain(domain string) bool {
 	return false
 }
 
+func IsValidTrialEmail(email string) bool {
+	local, domain, ok := parseStrictEmail(email)
+	if !ok {
+		return false
+	}
+	return local != "" && domain != ""
+}
+
+func parseStrictEmail(email string) (local, domain string, ok bool) {
+	email = strings.ToLower(strings.TrimSpace(email))
+	if email == "" || strings.ContainsAny(email, " \t\r\n") {
+		return "", "", false
+	}
+	addr, err := mail.ParseAddress(email)
+	if err != nil || addr.Address != email || addr.Name != "" {
+		return "", "", false
+	}
+	parts := strings.Split(addr.Address, "@")
+	if len(parts) != 2 {
+		return "", "", false
+	}
+	local = strings.TrimSpace(parts[0])
+	domain = strings.Trim(strings.TrimSpace(parts[1]), ".")
+	if local == "" || domain == "" || strings.Contains(domain, "..") || !strings.Contains(domain, ".") {
+		return "", "", false
+	}
+	return local, domain, true
+}
+
+func emailDomain(email string) string {
+	_, domain, ok := parseStrictEmail(email)
+	if !ok {
+		return ""
+	}
+	return domain
+}
+
+func isConfusableGmailDomain(domain string) bool {
+	switch strings.ToLower(strings.TrimSpace(domain)) {
+	case "gmaial.com", "gmial.com", "gmai.com", "gamil.com", "gmal.com", "gmail.co", "gmail.con":
+		return true
+	}
+	return false
+}
+
 // NormalizedEmailHasTrial returns true if any user with the same normalized email
 // already holds a trial subscription. Only performs the cross-user DB check when
 // normalization actually changes the email (i.e., dots removed or + alias stripped).