Fix installment payment when admin manually pay for order (#388)

* [MIT-1562]: Total amount for payment is pulled from order instead of cart when the payment page is triggered from admin.

* Fixed the issue with Japanese language Support in the secure form.

* Added unit test for installment

* Added unit test for installment

* Updated test

* Fix indentation

* Fix the tests after code chagne.

* Fix the spelling mistake.

* Reverted secure form changes.

---------

Co-authored-by: Aashish <[email protected]>

includes/gateway/class-omise-payment-installment.php

@@ -70,7 +70,8 @@ public function payment_fields()
 		parent::payment_fields();
 
 		$currency   = get_woocommerce_currency();
-		$cart_total = WC()->cart->total;
+		$cart_total = $this->getTotalAmount();
+
 		$capabilities = $this->backend->capabilities();
 		$installmentMinLimit = $capabilities->getInstallmentMinLimit();
 
@@ -84,6 +85,26 @@ public function payment_fields()
 		);
 	}
 
+	/**
+	 * Get the total amount of an order
+	 */
+	public function getTotalAmount()
+	{
+		global $wp;
+
+		if (
+			isset($wp->query_vars['order-pay']) &&
+			(int)$wp->query_vars['order-pay'] > 0
+		) {
+			$order_id = (int)$wp->query_vars['order-pay'];
+			$order = wc_get_order( $order_id );
+			return $order->get_total();
+		}
+
+		// if not an order page then get total from the cart
+		return WC()->cart->total;
+	}
+
 	/**
 	 * @inheritdoc
 	 */

tests/unit/includes/gateway/class-omise-payment-installment-test.php

@@ -0,0 +1,85 @@
+<?php
+
+use PHPUnit\Framework\TestCase;
+use Mockery;
+
+class Omise_Payment_Installment_Test extends TestCase
+{
+    public function setUp(): void
+    {
+        // Mocking the parent class
+        $offsite = Mockery::mock('overload:Omise_Payment_Offsite');
+        $offsite->shouldReceive('init_settings');
+        $offsite->shouldReceive('get_option');
+
+        // mocking WP built-in functions
+        if (!function_exists('wp_kses')) {
+            function wp_kses() {}
+        }
+
+        if (!function_exists('add_action')) {
+            function add_action() {}
+        }
+
+        require_once __DIR__ . '/../../../../includes/gateway/class-omise-payment-installment.php';
+    }
+
+    /**
+     * close mockery after tests are done
+     */
+    public function teardown(): void
+    {
+        Mockery::close();
+    }
+
+    /**
+     * @test
+     */
+    public function getTotalAmountFromAdminOrderpage()
+    {
+        // mocking built-in WooCommerce function
+        if (!function_exists('wc_get_order')) {
+            function wc_get_order() {
+                $class = new class {
+                    public $property;
+
+                    public function get_total() { 
+                        return 999999;
+                    }
+                };
+                return $class;
+            }
+        }
+
+        // mocking the WP global variable $wp
+        $wp = new stdClass();
+        $wp->query_vars = ['order-pay' => 123];
+        $GLOBALS['wp'] = $wp;
+
+        $installment = new Omise_Payment_Installment();
+        $total = $installment->getTotalAmount();
+
+        $this->assertEquals($total, 999999);
+    }
+
+    /**
+     * @test
+     */
+    public function getTotalAmountFromCart()
+    {
+        // mocking WC() method
+        if (!function_exists('WC')) {
+            function WC() {
+                $class = new stdClass();
+                $class->cart = new stdClass();
+                $class->cart->total = 999999;
+                return $class;
+            }
+        }
+
+        $installment = new Omise_Payment_Installment();
+        $total = $installment->getTotalAmount();
+
+        $this->assertEquals($total, 999999);
+    }
+}