<?php

declare(strict_types=1);

namespace App\Tests\Unit\Service;

use App\Service\ContributionAggregator;
use App\Service\ProviderInterface;
use PHPUnit\Framework\Attributes\CoversClass;
use PHPUnit\Framework\Attributes\Test;
use PHPUnit\Framework\TestCase;
use Psr\Log\LoggerInterface;

#[CoversClass(ContributionAggregator::class)]
final class ContributionAggregatorTest extends TestCase
{
    private LoggerInterface $logger;

    protected function setUp(): void
    {
        $this->logger = $this->createStub(LoggerInterface::class);
    }

    #[Test]
    public function it_returns_empty_array_when_no_providers_are_given(): void
    {
        $aggregator = new ContributionAggregator([], $this->logger);

        $result = $aggregator->aggregate();

        $this->assertSame([], $result);
    }

    #[Test]
    public function it_skips_unconfigured_providers(): void
    {
        $provider = $this->createStub(ProviderInterface::class);
        $provider->method('isConfigured')->willReturn(false);

        $aggregator = new ContributionAggregator([$provider], $this->logger);

        $result = $aggregator->aggregate();

        $this->assertSame([], $result);
    }

    #[Test]
    public function it_returns_contributions_from_a_configured_provider(): void
    {
        $provider = $this->createStub(ProviderInterface::class);
        $provider->method('isConfigured')->willReturn(true);
        $provider->method('fetch')->willReturn(['2024-01-01' => 3]);

        $aggregator = new ContributionAggregator([$provider], $this->logger);

        $result = $aggregator->aggregate();

        $this->assertSame(['2024-01-01' => 3], $result);
    }

    #[Test]
    public function it_sums_contributions_from_multiple_providers_on_the_same_date(): void
    {
        $providerA = $this->createStub(ProviderInterface::class);
        $providerA->method('isConfigured')->willReturn(true);
        $providerA->method('fetch')->willReturn(['2024-01-01' => 3, '2024-01-02' => 1]);

        $providerB = $this->createStub(ProviderInterface::class);
        $providerB->method('isConfigured')->willReturn(true);
        $providerB->method('fetch')->willReturn(['2024-01-01' => 2, '2024-01-03' => 5]);

        $aggregator = new ContributionAggregator([$providerA, $providerB], $this->logger);

        $result = $aggregator->aggregate();

        $this->assertSame(['2024-01-01' => 5, '2024-01-02' => 1, '2024-01-03' => 5], $result);
    }

    #[Test]
    public function it_continues_fetching_remaining_providers_when_one_throws(): void
    {
        $failing = $this->createStub(ProviderInterface::class);
        $failing->method('isConfigured')->willReturn(true);
        $failing->method('fetch')->willThrowException(new \RuntimeException('Network error'));

        $healthy = $this->createStub(ProviderInterface::class);
        $healthy->method('isConfigured')->willReturn(true);
        $healthy->method('fetch')->willReturn(['2024-01-01' => 7]);

        $aggregator = new ContributionAggregator([$failing, $healthy], $this->logger);

        $result = $aggregator->aggregate();

        $this->assertSame(['2024-01-01' => 7], $result);
    }

    #[Test]
    public function it_logs_a_warning_when_a_provider_fetch_throws(): void
    {
        $logger = $this->createMock(LoggerInterface::class);
        $logger->expects($this->once())->method('warning');

        $provider = $this->createStub(ProviderInterface::class);
        $provider->method('isConfigured')->willReturn(true);
        $provider->method('fetch')->willThrowException(new \RuntimeException('fail'));

        (new ContributionAggregator([$provider], $logger))->aggregate();
    }
}