fix(payment): re-pay with fresh provider out_trade_no

WeChat/Alipay/Epay reject reusing the same merchant order number when
params change. Allocate attempt-suffixed out_trade_no on resume pay,
map callbacks back to the local order, and best-effort close prior trades.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/AKSRT/Payment/Gateways/EpayGateway.php

@@ -44,9 +44,15 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 		}
 
 		$order_number = (string) ($order['order_number'] ?? '');
+		$out_trade_no = (string) ($order['out_trade_no'] ?? '');
+		if ($out_trade_no === '') {
+			$out_trade_no = class_exists('\AKSRT\Payment\OrderRepository')
+				? \AKSRT\Payment\OrderRepository::provider_out_trade_no($order)
+				: $order_number;
+		}
 		$amount       = (float) ($order['amount'] ?? 0);
 		$subject      = (string) ($order['subject'] ?? __('订单支付', 'aksrt'));
-		if ($order_number === '' || $amount <= 0) {
+		if ($order_number === '' || $out_trade_no === '' || $amount <= 0) {
 			return ['success' => false, 'message' => __('订单参数无效', 'aksrt')];
 		}
 
@@ -54,7 +60,7 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 		$params = [
 			'pid'          => $config['pid'],
 			'type'         => $this->channel,
-			'out_trade_no' => $order_number,
+			'out_trade_no' => $out_trade_no,
 			'notify_url'   => rest_url('aksrt/v1/payment/' . $this->get_id() . '/notify'),
 			'return_url'   => rest_url('aksrt/v1/payment/' . $this->get_id() . '/return'),
 			'name'         => mb_substr(wp_strip_all_tags($subject), 0, 127),
@@ -78,7 +84,7 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 			$body = json_decode((string) wp_remote_retrieve_body($response), true);
 			if (!is_array($body)) {
 				// Fall back to browser submit if mapi is unavailable.
-				return $this->browser_submit_result($config['apiurl'], $params, $order_number);
+				return $this->browser_submit_result($config['apiurl'], $params, $order_number, $out_trade_no);
 			}
 			$code = (int) ($body['code'] ?? 0);
 			if ($code !== 1) {
@@ -94,6 +100,7 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 				'success'      => true,
 				'payment_data' => [
 					'order_number' => $order_number,
+					'out_trade_no' => $out_trade_no,
 					'code_url'     => $qrcode,
 					'channel'      => $this->channel,
 				],
@@ -107,7 +114,7 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 			return $result;
 		}
 
-		return $this->browser_submit_result($config['apiurl'], $params, $order_number);
+		return $this->browser_submit_result($config['apiurl'], $params, $order_number, $out_trade_no);
 	}
 
 	public function verify_callback(\WP_REST_Request $request): array {
@@ -177,13 +184,14 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 			return ['success' => false, 'message' => __('易支付未配置', 'aksrt')];
 		}
 
+		$out_trade_no = $this->resolve_out_trade_no($order_number);
 		$config = $this->get_config();
 		// Common compatible query: api.php?act=order&pid&key&out_trade_no
 		$url = add_query_arg([
 			'act'          => 'order',
 			'pid'          => $config['pid'],
 			'key'          => $config['key'],
-			'out_trade_no' => $order_number,
+			'out_trade_no' => $out_trade_no,
 		], $this->endpoint($config['apiurl'], 'api.php'));
 
 		$response = wp_remote_get($url, ['timeout' => 20]);
@@ -205,7 +213,7 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 
 		return [
 			'success'        => true,
-			'order_number'   => (string) ($body['out_trade_no'] ?? $order_number),
+			'order_number'   => (string) ($body['out_trade_no'] ?? $out_trade_no),
 			'amount'         => $amount,
 			'transaction_id' => $tx,
 			'status'         => $paid ? 'paid' : 'pending',
@@ -297,16 +305,34 @@ class EpayGateway implements \AKSRT\Payment\GatewayInterface {
 	 * @param array<string,string> $params
 	 * @return array{success:bool,payment_url?:string,payment_data?:array,message?:string}
 	 */
-	private function browser_submit_result(string $apiurl, array $params, string $order_number): array {
+	/**
+	 * @param array<string,string> $params
+	 * @return array{success:bool,payment_url?:string,payment_data?:array,message?:string}
+	 */
+	private function browser_submit_result(string $apiurl, array $params, string $order_number, string $out_trade_no = ''): array {
 		$url = add_query_arg($params, $this->endpoint($apiurl, 'submit.php'));
 		return [
 			'success'      => true,
 			'payment_url'  => $url,
 			'payment_data' => [
 				'order_number' => $order_number,
+				'out_trade_no' => $out_trade_no !== '' ? $out_trade_no : $order_number,
 				'channel'      => $this->channel,
 			],
 			'message'      => __('易支付支付链接已生成', 'aksrt'),
 		];
 	}
+
+	/**
+	 * Map local order_number → provider out_trade_no (supports resume attempts).
+	 */
+	private function resolve_out_trade_no(string $order_number): string {
+		if (class_exists('\AKSRT\Payment\OrderRepository')) {
+			$order = \AKSRT\Payment\OrderRepository::get_instance()->get($order_number);
+			if ($order) {
+				return \AKSRT\Payment\OrderRepository::provider_out_trade_no($order);
+			}
+		}
+		return $order_number;
+	}
 }