<?php

namespace App\Tests\MyEp\Import;

use App\MyEp\Api\AccessTokenProvider;
use App\MyEp\Api\ApiClient;
use App\MyEp\Api\ApiException;
use App\MyEp\Import\TravelExportClient;
use PHPUnit\Framework\TestCase;
use Psr\Log\NullLogger;
use Symfony\Component\Cache\Adapter\ArrayAdapter;
use Symfony\Component\HttpClient\MockHttpClient;
use Symfony\Component\HttpClient\Response\MockResponse;

class TravelExportClientTest extends TestCase
{
    public function testEveryPageIsRead(): void
    {
        $httpClient = $this->mockClient([
            $this->page([$this->row(1, 100), $this->row(2, 200)], 1, 2),
            $this->page([$this->row(3, 300)], 2, 2),
        ]);

        $rows = $this->getClientInstance($httpClient)->fetchAll()->rows;

        $this->assertCount(3, $rows);
        $this->assertEquals([1, 2, 3], array_map(fn ($row) => $row->busProId, $rows));
        $this->assertEquals(2, $httpClient->getRequestsCount());
    }

    public function testASinglePageIsNotFollowedByAnother(): void
    {
        $httpClient = $this->mockClient([$this->page([$this->row(1, 100)], 1, 1)]);

        $this->getClientInstance($httpClient)->fetchAll();

        $this->assertEquals(1, $httpClient->getRequestsCount());
    }

    public function testTheRequestedPageIsPassedOn(): void
    {
        $urls = [];
        $httpClient = new MockHttpClient(function (string $method, string $url) use (&$urls) {
            $urls[] = $url;

            return $this->page([$this->row(count($urls), 100)], count($urls), 2);
        }, 'https://myep.example/');

        $this->getClientInstance($httpClient)->fetchAll();

        $this->assertStringContainsString('page=1', $urls[0]);
        $this->assertStringContainsString('page=2', $urls[1]);
        $this->assertStringContainsString('perPage=500', $urls[0]);
    }

    public function testAnUnusableRowIsSkippedRatherThanFatal(): void
    {
        $httpClient = $this->mockClient([
            $this->page([
                ['busProId' => 1],
                $this->row(2, 200),
            ], 1, 1),
        ]);

        $rows = $this->getClientInstance($httpClient)->fetchAll()->rows;

        $this->assertCount(1, $rows);
        $this->assertEquals(2, $rows[0]->busProId);
    }

    public function testAnEmptyExportYieldsNoRows(): void
    {
        $httpClient = $this->mockClient([$this->page([], 1, 1)]);

        $this->assertEquals([], $this->getClientInstance($httpClient)->fetchAll()->rows);
    }

    public function testAPayloadWithoutADataListFails(): void
    {
        $httpClient = $this->mockClient([new MockResponse('{"meta":{"totalPages":1}}')]);

        $this->expectException(ApiException::class);

        $this->getClientInstance($httpClient)->fetchAll();
    }

    private function row(int $busProId, int $hotelBusProId): array
    {
        return [
            'busProId' => $busProId,
            'code' => 'CODE'.$busProId,
            'product' => 'Produkt '.$busProId,
            'dateFrom' => '2026-04-04',
            'dateTo' => '2026-04-11',
            'hotel' => [
                'busProId' => $hotelBusProId,
                'code' => 'AAA',
                'name' => 'Haus',
                'costUnit' => null,
                'country' => 'CH',
                'countryCode' => 'ch',
            ],
            'pickups' => [],
        ];
    }

    /**
     * Both counters are losses MyE&P made on its side - a dropped travel, a boarding point with no
     * town - and the import is the only place they surface, so the client has to carry them out.
     */
    public function testTheCountersMyEpReportsAreCarriedOut(): void
    {
        $httpClient = $this->mockClient([$this->page([$this->row(1, 100)], 1, 1, skipped: 3, pickupsWithoutMasterData: 21)]);

        $export = $this->getClientInstance($httpClient)->fetchAll();

        $this->assertSame(3, $export->skipped);
        $this->assertSame(21, $export->pickupsWithoutMasterData);
        $this->assertSame('2026-09-29T03:20:00+02:00', $export->generatedAt);
    }

    /**
     * They describe the whole export rather than the page, so they repeat unchanged and the first
     * page answers for the run. Reading the last one instead would be just as correct today and
     * wrong the moment a page is served from a newer build.
     */
    public function testTheCountersAreReadFromTheFirstPage(): void
    {
        $httpClient = $this->mockClient([
            $this->page([$this->row(1, 100)], 1, 2, skipped: 3, pickupsWithoutMasterData: 21),
            $this->page([$this->row(2, 200)], 2, 2, skipped: 99, pickupsWithoutMasterData: 99),
        ]);

        $export = $this->getClientInstance($httpClient)->fetchAll();

        $this->assertSame(3, $export->skipped);
        $this->assertSame(21, $export->pickupsWithoutMasterData);
    }

    /**
     * An export whose meta block says nothing must not read as one that dropped nothing by
     * accident of a missing key, but zero is the only honest default available here.
     */
    public function testAMetaBlockWithoutCountersReadsAsZero(): void
    {
        $httpClient = new MockHttpClient(
            [new MockResponse(json_encode(['data' => [$this->row(1, 100)], 'meta' => ['totalPages' => 1]]))],
            'https://myep.example/',
        );

        $export = $this->getClientInstance($httpClient)->fetchAll();

        $this->assertSame(0, $export->skipped);
        $this->assertSame(0, $export->pickupsWithoutMasterData);
        $this->assertNull($export->generatedAt);
    }

    private function page(
        array $rows,
        int $page,
        int $totalPages,
        int $skipped = 0,
        int $pickupsWithoutMasterData = 0,
    ): MockResponse {
        return new MockResponse(json_encode([
            'data' => $rows,
            'meta' => [
                'page' => $page,
                'perPage' => 500,
                'total' => count($rows),
                'totalPages' => $totalPages,
                'skipped' => $skipped,
                'pickupsWithoutMasterData' => $pickupsWithoutMasterData,
                'generatedAt' => '2026-09-29T03:20:00+02:00',
            ],
        ]));
    }

    private function mockClient(array $responses): MockHttpClient
    {
        return new MockHttpClient($responses, 'https://myep.example/');
    }

    private function getClientInstance(MockHttpClient $httpClient): TravelExportClient
    {
        $tokenClient = new MockHttpClient(
            fn () => new MockResponse('{"access_token":"token","expires_in":600}'),
            'https://myep.example/',
        );

        $tokens = new AccessTokenProvider($tokenClient, new ArrayAdapter(), new NullLogger(), [
            'client_id' => 'team-app',
            'client_secret' => 'secret',
        ]);

        return new TravelExportClient(new ApiClient($httpClient, $tokens, new NullLogger()), new NullLogger());
    }
}