fix is_active student flag logic and make moving with enrollment status

tests/app/Services/EnrollmentStatusServiceTest.php

@@ -0,0 +1,45 @@
+<?php
+
+namespace Tests\App\Services;
+
+use App\Services\EnrollmentStatusService;
+use CodeIgniter\Database\BaseConnection;
+use InvalidArgumentException;
+use PHPUnit\Framework\TestCase;
+
+final class EnrollmentStatusServiceTest extends TestCase
+{
+    /**
+     * @dataProvider statusMappingProvider
+     */
+    public function testEnrollmentStatusMapsToStudentActivity(string $status, int $expected): void
+    {
+        $service = new EnrollmentStatusService($this->createMock(BaseConnection::class));
+
+        $this->assertSame($expected, $service->activeFlagForStatus($status));
+    }
+
+    public static function statusMappingProvider(): array
+    {
+        return [
+            ['admission under review', 1],
+            ['review & decision', 1],
+            ['payment pending', 1],
+            ['enrolled', 1],
+            ['withdraw under review', 1],
+            ['refund pending', 1],
+            ['denied', 0],
+            ['withdrawn', 0],
+            ['waitlist', 0],
+        ];
+    }
+
+    public function testUnknownStatusIsRejected(): void
+    {
+        $service = new EnrollmentStatusService($this->createMock(BaseConnection::class));
+
+        $this->expectException(InvalidArgumentException::class);
+
+        $service->activeFlagForStatus('accepted');
+    }
+}