<?php

declare(strict_types=1);

namespace App\Tests\Service;

use App\BusProNet\XmlLoader\HotelLoader;
use App\BusProNet\XmlLoader\TravelLoader;
use App\Service\TravelIndex;
use App\Service\TravelSnapshotManager;
use PHPUnit\Framework\TestCase;
use Psr\Log\LoggerInterface;

class TravelIndexTest extends TestCase
{
    private TravelIndex $service;
    private TravelLoader $travelLoader;
    private HotelLoader $hotelLoader;
    private TravelSnapshotManager $travelSnapshotService;
    private LoggerInterface $logger;

    protected function setUp(): void
    {
        $this->travelLoader = $this->createMock(TravelLoader::class);
        $this->hotelLoader = $this->createMock(HotelLoader::class);
        $this->travelSnapshotService = $this->createMock(TravelSnapshotManager::class);
        $this->logger = $this->createMock(LoggerInterface::class);

        $this->service = new TravelIndex(
            $this->travelLoader,
            $this->hotelLoader,
            $this->travelSnapshotService,
            $this->logger,
        );
    }

    // -------------------------------------------------------------------------
    // generateFilesMap
    // -------------------------------------------------------------------------

    public function testGenerateFilesMapMergesXmlAndSnapshotMappings(): void
    {
        $dateId = 100;
        $hotelId = 200;
        $snapshotOnlyDateId = 300;

        $xmlMapping = [
            $dateId => ['id' => $dateId, 'code' => 'ABC', 'hotels' => [
                $hotelId => ['id' => $hotelId],
            ]],
        ];
        $snapshotMapping = [
            $dateId => ['id' => $dateId, 'code' => 'ABC', 'hotels' => [
                999 => ['id' => 999], // extra hotel only in snapshot
            ]],
            $snapshotOnlyDateId => ['id' => $snapshotOnlyDateId, 'code' => 'XYZ', 'hotels' => []],
        ];

        $this->travelLoader->method('generateFilesMap')->willReturn($xmlMapping);
        $this->travelSnapshotService->method('generateMapping')->willReturn($snapshotMapping);

        $result = $this->service->generateFilesMap();

        // XML entry is preserved
        $this->assertArrayHasKey($dateId, $result);
        // Snapshot-only date is merged in
        $this->assertArrayHasKey($snapshotOnlyDateId, $result);
        // Extra hotel from snapshot is added to the XML date entry
        $this->assertArrayHasKey(999, $result[$dateId]['hotels']);
        // Original XML hotel is still present
        $this->assertArrayHasKey($hotelId, $result[$dateId]['hotels']);
    }

    public function testGenerateFilesMapIsMemoizedWithinRequest(): void
    {
        $mapping = [100 => ['id' => 100, 'code' => 'A', 'hotels' => []]];

        $this->travelLoader
            ->expects($this->once())
            ->method('generateFilesMap')
            ->willReturn($mapping);

        $this->travelSnapshotService
            ->expects($this->once())
            ->method('generateMapping')
            ->willReturn([]);

        // Two calls — loaders invoked only once
        $this->service->generateFilesMap();
        $result = $this->service->generateFilesMap();

        $this->assertSame($mapping, $result);
    }

    public function testGenerateFilesMapFallsBackToSnapshotsOnXmlFailure(): void
    {
        $snapshotMapping = [100 => ['id' => 100, 'code' => 'A', 'hotels' => []]];

        $this->travelLoader
            ->method('generateFilesMap')
            ->willThrowException(new \RuntimeException('Filesystem error'));

        $this->travelSnapshotService
            ->method('generateMapping')
            ->willReturn($snapshotMapping);

        $this->logger
            ->expects($this->once())
            ->method('warning')
            ->with('Failed to generate XML files mapping, fallback to snapshots only', $this->arrayHasKey('error'));

        $result = $this->service->generateFilesMap();

        $this->assertSame($snapshotMapping, $result);
    }

    // -------------------------------------------------------------------------
    // mapDateCodeToId
    // -------------------------------------------------------------------------

    public function testMapDateCodeToIdReturnsMatchingId(): void
    {
        $this->travelLoader->method('generateFilesMap')->willReturn([
            42 => ['id' => 42, 'code' => 'WI25', 'hotels' => []],
        ]);
        $this->travelSnapshotService->method('generateMapping')->willReturn([]);

        $result = $this->service->mapDateCodeToId('WI25');

        $this->assertSame(42, $result);
    }

    public function testMapDateCodeToIdReturnsNullWhenNotFound(): void
    {
        $this->travelLoader->method('generateFilesMap')->willReturn([]);
        $this->travelSnapshotService->method('generateMapping')->willReturn([]);

        $result = $this->service->mapDateCodeToId('UNKNOWN');

        $this->assertNull($result);
    }

    // -------------------------------------------------------------------------
    // mapHotelCodeToId
    // -------------------------------------------------------------------------

    public function testMapHotelCodeToIdDelegatesToHotelLoader(): void
    {
        $this->hotelLoader
            ->expects($this->once())
            ->method('mapCodeToId')
            ->with('HTL001')
            ->willReturn(77);

        $result = $this->service->mapHotelCodeToId('HTL001');

        $this->assertSame(77, $result);
    }

    public function testMapHotelCodeToIdReturnsNullOnException(): void
    {
        $this->hotelLoader
            ->method('mapCodeToId')
            ->willThrowException(new \RuntimeException('Not found'));

        $result = $this->service->mapHotelCodeToId('MISSING');

        $this->assertNull($result);
    }

    // -------------------------------------------------------------------------
    // mapDateIdToProductId
    // -------------------------------------------------------------------------

    public function testMapDateIdToProductIdPrefersSnapshot(): void
    {
        $this->travelSnapshotService
            ->expects($this->once())
            ->method('findProductIdByDateId')
            ->with(100)
            ->willReturn(999);

        $this->travelLoader
            ->expects($this->never())
            ->method('mapDateIdToProductId');

        $result = $this->service->mapDateIdToProductId(100);

        $this->assertSame(999, $result);
    }

    public function testMapDateIdToProductIdFallsBackToLoaderWhenSnapshotReturnsNull(): void
    {
        $this->travelSnapshotService
            ->expects($this->once())
            ->method('findProductIdByDateId')
            ->with(100)
            ->willReturn(null);

        $this->travelLoader
            ->expects($this->once())
            ->method('mapDateIdToProductId')
            ->with(100)
            ->willReturn(42);

        $result = $this->service->mapDateIdToProductId(100);

        $this->assertSame(42, $result);
    }

    // -------------------------------------------------------------------------
    // existsLocally
    // -------------------------------------------------------------------------

    public function testExistsLocallyTrueFromSnapshot(): void
    {
        $dateId = 12345;
        $hotelId = 67890;

        $this->travelSnapshotService
            ->expects($this->once())
            ->method('exists')
            ->with($dateId, $hotelId)
            ->willReturn(true);

        $this->travelLoader
            ->expects($this->never())
            ->method('generateFilesMap');

        $this->assertTrue($this->service->existsLocally($dateId, $hotelId));
    }

    public function testExistsLocallyTrueFromXmlMap(): void
    {
        $dateId = 12345;
        $hotelId = 67890;
        $mapping = [
            $dateId => [
                'id' => $dateId,
                'hotels' => [$hotelId => ['id' => $hotelId]],
            ],
        ];

        $this->travelSnapshotService->method('exists')->willReturn(false);
        $this->travelLoader->method('generateFilesMap')->willReturn($mapping);
        $this->travelSnapshotService->method('generateMapping')->willReturn([]);

        $this->assertTrue($this->service->existsLocally($dateId, $hotelId));
    }

    public function testExistsLocallyFalseNoTravel(): void
    {
        $this->travelSnapshotService->method('exists')->willReturn(false);
        $this->travelLoader->method('generateFilesMap')->willReturn([]);
        $this->travelSnapshotService->method('generateMapping')->willReturn([]);

        $this->assertFalse($this->service->existsLocally(12345, 67890));
    }

    public function testExistsLocallyFalseNoHotel(): void
    {
        $dateId = 12345;
        $hotelId = 67890;
        $mapping = [
            $dateId => ['id' => $dateId, 'hotels' => []],
        ];

        $this->travelSnapshotService->method('exists')->willReturn(false);
        $this->travelLoader->method('generateFilesMap')->willReturn($mapping);
        $this->travelSnapshotService->method('generateMapping')->willReturn([]);

        $this->assertFalse($this->service->existsLocally($dateId, $hotelId));
    }

    // -------------------------------------------------------------------------
    // getAvailableSources
    // -------------------------------------------------------------------------

    public function testGetAvailableSourcesReturnsBothFlags(): void
    {
        $dateId = 12345;
        $hotelId = 67890;
        $mapping = [
            $dateId => ['id' => $dateId, 'hotels' => [$hotelId => []]],
        ];

        $this->travelSnapshotService->method('exists')->willReturn(false);
        $this->travelSnapshotService->method('generateMapping')->willReturn([]);
        $this->travelSnapshotService->method('findProductIdByDateId')->willReturn(null);
        $this->travelLoader->method('generateFilesMap')->willReturn($mapping);
        $this->travelLoader->method('mapDateIdToProductId')->with($dateId)->willReturn(555);

        $result = $this->service->getAvailableSources($dateId, $hotelId);

        $this->assertEquals(['local' => true, 'remote' => true], $result);
    }
}