feat: 组合支付

packages/toolkit/src/Payment/Payment.ts

@@ -148,7 +148,7 @@ export class Payment {
                     return this.balance > 0 && this.balance < totalAmount && !Utils.isWechat()
             }
         }).map(item => {
-            const {payBalance} = this.computeAmount(totalAmount, this.balance)
+            const {payBalance} = this.computeAmountForCombination(totalAmount, this.balance)
             switch (item.value) {
                 case PayType.BALANCE:
                     return {
@@ -174,6 +174,19 @@ export class Payment {
         return {payAmount, payBalance}
     }
 
+    computeAmountForCombination(totalAmount: number, balance: number = 0): { payAmount: number, payBalance: number } {
+        let payBalance = 0, payAmount = 0
+        if (balance === 0) {
+            payAmount = totalAmount
+        } else if (balance > 0 && balance < totalAmount) {
+            payBalance = balance;
+            payAmount = totalAmount - balance;
+        } else {
+            payBalance = totalAmount
+        }
+        return {payAmount, payBalance}
+    } 
+
     async toPay(params: ToPayParams): Promise<ToPayReturns> {
         const {totalAmount, payType, returnUrl, orderId, redirectUrl, payId} = params
         let quitUrl = params.quitUrl
@@ -237,13 +250,15 @@ export class Payment {
         if (payChannel === PayChannel.WX_MWEB || payChannel === PayChannel.WX_JSAPI) {
             quitUrl = redirectUrl
         }
+        const { payAmount, payBalance } = this.supportCombination ? this.computeAmountForCombination(totalAmount, this.balance) : this.computeAmount(totalAmount, payType);
         const doUnifiedParams: DoUnifiedParams = {
             returnUrl,
             quitUrl,
             orderId,
             payType,
             payId,
-            ...this.computeAmount(totalAmount, payType)
+            payAmount, 
+            payBalance
         }
         if (payChannel !== null) {
             doUnifiedParams.payChannel = payChannel