<?php

namespace Tests\Unit\Services;

use App\Exceptions\RoutingMismatchException;
use App\Models\Feed;
use App\Models\Language;
use App\Models\PlatformChannel;
use App\Models\PlatformInstance;
use App\Services\RoutingValidationService;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Support\Collection;
use Tests\TestCase;

class RoutingValidationServiceTest extends TestCase
{
    use RefreshDatabase;

    private RoutingValidationService $service;

    protected function setUp(): void
    {
        parent::setUp();
        $this->service = new RoutingValidationService();
    }

    public function test_validate_language_compatibility_passes_when_feed_has_no_language(): void
    {
        $feed = Feed::factory()->create(['language_id' => null]);
        
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $esLanguage = Language::factory()->create(['short_code' => 'es']);
        $instance = PlatformInstance::factory()->create();
        
        $channels = collect([
            PlatformChannel::factory()->create(['language_id' => $enLanguage->id, 'platform_instance_id' => $instance->id]),
            PlatformChannel::factory()->create(['language_id' => $esLanguage->id, 'platform_instance_id' => $instance->id]),
        ]);

        $this->service->validateLanguageCompatibility($feed, $channels);

        // If we get here without exception, the test passes
        $this->assertTrue(true);
    }

    public function test_validate_language_compatibility_passes_when_channels_have_no_language(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channels = collect([
            PlatformChannel::factory()->create(['language_id' => null, 'platform_instance_id' => $instance->id]),
            PlatformChannel::factory()->create(['language_id' => null, 'platform_instance_id' => $instance->id]),
        ]);

        $this->service->validateLanguageCompatibility($feed, $channels);

        // If we get here without exception, the test passes
        $this->assertTrue(true);
    }

    public function test_validate_language_compatibility_passes_when_languages_match(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channels = collect([
            PlatformChannel::factory()->create(['language_id' => $enLanguage->id, 'platform_instance_id' => $instance->id]),
            PlatformChannel::factory()->create(['language_id' => $enLanguage->id, 'platform_instance_id' => $instance->id]),
        ]);

        $this->service->validateLanguageCompatibility($feed, $channels);

        // If we get here without exception, the test passes
        $this->assertTrue(true);
    }

    public function test_validate_language_compatibility_passes_with_mixed_null_and_matching_languages(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channels = collect([
            PlatformChannel::factory()->create(['language_id' => $enLanguage->id, 'platform_instance_id' => $instance->id]),
            PlatformChannel::factory()->create(['language_id' => null, 'platform_instance_id' => $instance->id]),
            PlatformChannel::factory()->create(['language_id' => $enLanguage->id, 'platform_instance_id' => $instance->id]),
        ]);

        $this->service->validateLanguageCompatibility($feed, $channels);

        // If we get here without exception, the test passes
        $this->assertTrue(true);
    }

    public function test_validate_language_compatibility_throws_exception_when_languages_mismatch(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $esLanguage = Language::factory()->create(['short_code' => 'es']);
        
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channel = PlatformChannel::factory()->create(['language_id' => $esLanguage->id, 'platform_instance_id' => $instance->id]);
        $channels = collect([$channel]);

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

        $this->service->validateLanguageCompatibility($feed, $channels);
    }

    public function test_validate_language_compatibility_throws_exception_on_first_mismatch(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $esLanguage = Language::factory()->create(['short_code' => 'es']);
        
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $mismatchChannel = PlatformChannel::factory()->create(['language_id' => $esLanguage->id, 'platform_instance_id' => $instance->id]);
        $matchingChannel = PlatformChannel::factory()->create(['language_id' => $enLanguage->id, 'platform_instance_id' => $instance->id]);
        
        $channels = collect([$mismatchChannel, $matchingChannel]);

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

        $this->service->validateLanguageCompatibility($feed, $channels);
    }

    public function test_validate_language_compatibility_with_empty_collection(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        $channels = collect([]);

        $this->service->validateLanguageCompatibility($feed, $channels);

        // If we get here without exception, the test passes
        $this->assertTrue(true);
    }

    public function test_validate_language_compatibility_exception_contains_correct_feed_and_channel(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $esLanguage = Language::factory()->create(['short_code' => 'es']);
        
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channel = PlatformChannel::factory()->create(['language_id' => $esLanguage->id, 'platform_instance_id' => $instance->id]);
        $channels = collect([$channel]);

        try {
            $this->service->validateLanguageCompatibility($feed, $channels);
            $this->fail('Expected RoutingMismatchException to be thrown');
        } catch (RoutingMismatchException $e) {
            // Exception should contain the feed and channel that caused the mismatch
            $this->assertInstanceOf(RoutingMismatchException::class, $e);
        }
    }

    public function test_validate_language_compatibility_with_multiple_mismatching_channels(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $esLanguage = Language::factory()->create(['short_code' => 'es']);
        $frLanguage = Language::factory()->create(['short_code' => 'fr']);
        
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channels = collect([
            PlatformChannel::factory()->create(['language_id' => $esLanguage->id, 'platform_instance_id' => $instance->id]),  // This should trigger exception
            PlatformChannel::factory()->create(['language_id' => $frLanguage->id, 'platform_instance_id' => $instance->id]),  // This won't be reached
        ]);

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

        $this->service->validateLanguageCompatibility($feed, $channels);
    }

    public function test_validate_language_compatibility_ignores_channels_after_first_mismatch(): void
    {
        $enLanguage = Language::factory()->create(['short_code' => 'en']);
        $esLanguage = Language::factory()->create(['short_code' => 'es']);
        $frLanguage = Language::factory()->create(['short_code' => 'fr']);
        
        $feed = Feed::factory()->create(['language_id' => $enLanguage->id]);
        
        $instance = PlatformInstance::factory()->create();
        $channels = collect([
            PlatformChannel::factory()->create(['language_id' => null, 'platform_instance_id' => $instance->id]),  // Should be skipped
            PlatformChannel::factory()->create(['language_id' => $esLanguage->id, 'platform_instance_id' => $instance->id]),  // Should cause exception
            PlatformChannel::factory()->create(['language_id' => $frLanguage->id, 'platform_instance_id' => $instance->id]),  // Should not be reached
        ]);

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

        $this->service->validateLanguageCompatibility($feed, $channels);
    }
}