fix: 参照company项目重写BepUsdt支付：amount用%.2f格式化，请求体直接序列化map

backend/internal/api/handlers/payment.go

@@ -25,16 +25,6 @@ func NewPaymentHandler() *PaymentHandler {
 	return &PaymentHandler{}
 }
 
-type BepUsdtCreateRequest struct {
-	TradeType   string  `json:"trade_type,omitempty"`
-	OrderID     string  `json:"order_id"`
-	Amount      float64 `json:"amount"`
-	NotifyURL   string  `json:"notify_url"`
-	RedirectURL string  `json:"redirect_url,omitempty"`
-	Signature   string  `json:"signature"`
-	Timestamp   int64   `json:"timestamp"`
-}
-
 func (h *PaymentHandler) CreatePayment(c *gin.Context) {
 	userID := c.GetUint("user_id")
 	orderID, _ := strconv.Atoi(c.Param("id"))
@@ -76,39 +66,35 @@ func (h *PaymentHandler) CreatePayment(c *gin.Context) {
 
 	notifyURL := fmt.Sprintf("%s/api/payment/bepusdt/notify", baseURL)
 	redirectURL := fmt.Sprintf("%s/orders/%d", baseURL, order.ID)
-	timestamp := time.Now().Unix()
-
-	amountStr := fmt.Sprint(order.TotalAmount)
 
 	params := map[string]string{
 		"order_id":     strconv.Itoa(int(order.ID)),
-		"amount":       amountStr,
+		"amount":       fmt.Sprintf("%.2f", order.TotalAmount),
 		"notify_url":   notifyURL,
 		"redirect_url": redirectURL,
-		"timestamp":    strconv.FormatInt(timestamp, 10),
 	}
 	if tradeType != "" {
 		params["trade_type"] = tradeType
 	}
 
 	signature := signBepUsdt(params, apiToken)
+	params["signature"] = signature
 
 	log.Printf("[BepUsdt] signature params: %v", params)
 	log.Printf("[BepUsdt] signature: %s, token: %s", signature, apiToken)
 
-	reqBody := BepUsdtCreateRequest{
-		TradeType:   tradeType,
-		OrderID:     strconv.Itoa(int(order.ID)),
-		Amount:      order.TotalAmount,
-		NotifyURL:   notifyURL,
-		RedirectURL: redirectURL,
-		Signature:   signature,
-		Timestamp:   timestamp,
-	}
-
-	body, _ := json.Marshal(reqBody)
+	body, _ := json.Marshal(params)
 	log.Printf("[BepUsdt] request body: %s", string(body))
-	resp, err := http.Post(apiURL+"/api/v1/order/create-transaction", "application/json", strings.NewReader(string(body)))
+
+	req, err := http.NewRequest("POST", apiURL+"/api/v1/order/create-transaction", strings.NewReader(string(body)))
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create request"})
+		return
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	client := &http.Client{Timeout: 30 * time.Second}
+	resp, err := client.Do(req)
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to connect payment gateway"})
 		return
@@ -116,7 +102,6 @@ func (h *PaymentHandler) CreatePayment(c *gin.Context) {
 	defer resp.Body.Close()
 
 	respBody, _ := io.ReadAll(resp.Body)
-
 	log.Printf("[BepUsdt] response: %s", string(respBody))
 
 	var result map[string]interface{}
@@ -252,7 +237,7 @@ func (h *PaymentHandler) CheckPaymentStatus(c *gin.Context) {
 func signBepUsdt(params map[string]string, token string) string {
 	keys := make([]string, 0, len(params))
 	for k := range params {
-		if params[k] != "" {
+		if params[k] != "" && k != "signature" && k != "sign_type" {
 			keys = append(keys, k)
 		}
 	}