<?php

namespace Tests\Feature\Concurrency;

use App\Models\FinanceDocument;
use App\Models\Member;
use App\Models\MembershipPayment;
use App\Models\User;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Storage;
use Tests\TestCase;
use Tests\Traits\CreatesFinanceData;
use Tests\Traits\CreatesMemberData;
use Tests\Traits\SeedsRolesAndPermissions;

/**
 * Concurrency Tests
 *
 * Tests concurrent access and race condition handling.
 */
class ConcurrencyTest extends TestCase
{
    use RefreshDatabase, SeedsRolesAndPermissions, CreatesMemberData, CreatesFinanceData;

    protected function setUp(): void
    {
        parent::setUp();
        Storage::fake('private');
        Storage::fake('local');
        $this->seedRolesAndPermissions();
    }

    /**
     * Test concurrent payment approval attempts
     */
    public function test_concurrent_payment_approval_attempts(): void
    {
        $cashier1 = $this->createCashier();
        $cashier2 = $this->createCashier(['email' => 'cashier2@test.com']);

        $data = $this->createMemberWithPendingPayment();
        $payment = $data['payment'];

        // First cashier approves
        $response1 = $this->actingAs($cashier1)->post(
            route('admin.membership-payments.approve', $payment)
        );

        // Refresh to simulate concurrent access
        $payment->refresh();

        // Second cashier tries to approve (should be blocked)
        $response2 = $this->actingAs($cashier2)->post(
            route('admin.membership-payments.approve', $payment)
        );

        // Only one should succeed
        $this->assertTrue(
            $response1->isRedirect() || $response2->isRedirect()
        );
    }

    /**
     * Test concurrent member status update
     */
    public function test_concurrent_member_status_update(): void
    {
        $admin = $this->createAdmin();
        $member = $this->createPendingMember();

        // Load same member twice
        $member1 = Member::find($member->id);
        $member2 = Member::find($member->id);

        // Update from first instance
        $member1->membership_status = Member::STATUS_ACTIVE;
        $member1->save();

        // Update from second instance (stale data)
        $member2->membership_status = Member::STATUS_SUSPENDED;
        $member2->save();

        // Final state should be the last update
        $member->refresh();
        $this->assertEquals(Member::STATUS_SUSPENDED, $member->membership_status);
    }

    /**
     * Test concurrent finance document approval
     */
    public function test_concurrent_finance_document_approval(): void
    {
        $cashier = $this->createCashier();
        $accountant = $this->createAccountant();

        $document = $this->createFinanceDocument([
            'status' => FinanceDocument::STATUS_PENDING,
        ]);

        // Cashier approves
        $this->actingAs($cashier)->post(
            route('admin.finance-documents.approve', $document)
        );

        $document->refresh();
        $this->assertEquals(FinanceDocument::STATUS_APPROVED_CASHIER, $document->status);

        // Accountant tries to approve same document at pending status
        // This should work since status has changed
        $response = $this->actingAs($accountant)->post(
            route('admin.finance-documents.approve', $document)
        );

        $document->refresh();
        $this->assertEquals(FinanceDocument::STATUS_APPROVED_ACCOUNTANT, $document->status);
    }

    /**
     * Test transaction rollback on failure
     */
    public function test_transaction_rollback_on_failure(): void
    {
        $admin = $this->createAdmin();
        $initialCount = Member::count();

        try {
            DB::transaction(function () use ($admin) {
                Member::factory()->create();
                throw new \Exception('Simulated failure');
            });
        } catch (\Exception $e) {
            // Expected
        }

        // Count should remain unchanged
        $this->assertEquals($initialCount, Member::count());
    }

    /**
     * Test unique constraint handling
     */
    public function test_unique_constraint_handling(): void
    {
        $existingUser = User::factory()->create(['email' => 'unique@test.com']);

        // Attempt to create user with same email
        $this->expectException(\Illuminate\Database\QueryException::class);

        User::factory()->create(['email' => 'unique@test.com']);
    }

    /**
     * Test sequential number generation under load
     */
    public function test_sequential_number_generation_under_load(): void
    {
        $admin = $this->createAdmin();

        // Create multiple documents rapidly
        $numbers = [];
        for ($i = 0; $i < 10; $i++) {
            $document = $this->createFinanceDocument();
            $numbers[] = $document->document_number;
        }

        // All numbers should be unique
        $this->assertEquals(count($numbers), count(array_unique($numbers)));
    }

    /**
     * Test member number uniqueness under concurrent creation
     */
    public function test_member_number_uniqueness_under_concurrent_creation(): void
    {
        $members = [];
        for ($i = 0; $i < 10; $i++) {
            $members[] = $this->createMember([
                'full_name' => 'Test Member '.$i,
            ]);
        }

        $memberNumbers = array_map(fn ($m) => $m->member_number, $members);

        // All member numbers should be unique
        $this->assertEquals(count($memberNumbers), count(array_unique($memberNumbers)));
    }

    /**
     * Test optimistic locking for updates
     */
    public function test_optimistic_locking_scenario(): void
    {
        $document = $this->createFinanceDocument();
        $originalAmount = $document->amount;

        // Load same document twice
        $doc1 = FinanceDocument::find($document->id);
        $doc2 = FinanceDocument::find($document->id);

        // First update
        $doc1->amount = $originalAmount + 100;
        $doc1->save();

        // Second update (should overwrite)
        $doc2->amount = $originalAmount + 200;
        $doc2->save();

        $document->refresh();
        $this->assertEquals($originalAmount + 200, $document->amount);
    }

    /**
     * Test deadlock prevention
     */
    public function test_deadlock_prevention(): void
    {
        $this->assertTrue(true);
        // Note: Actual deadlock testing requires specific database conditions
        // This placeholder confirms the test infrastructure is in place
    }

    /**
     * Test race condition in approval workflow
     */
    public function test_race_condition_in_approval_workflow(): void
    {
        $cashier = $this->createCashier();
        $document = $this->createFinanceDocument([
            'status' => FinanceDocument::STATUS_PENDING,
        ]);

        // Simulate multiple approval attempts
        $approvalCount = 0;
        for ($i = 0; $i < 3; $i++) {
            $doc = FinanceDocument::find($document->id);
            if ($doc->status === FinanceDocument::STATUS_PENDING) {
                $this->actingAs($cashier)->post(
                    route('admin.finance-documents.approve', $doc)
                );
                $approvalCount++;
            }
        }

        // Only first approval should change status
        $document->refresh();
        $this->assertEquals(FinanceDocument::STATUS_APPROVED_CASHIER, $document->status);
    }
}