<?php

namespace Tests\Unit\Services;

use App\Events\PerceptronTrainingIteration;
use App\Services\IterationEventBuffer\PerceptronIterationEventBuffer;
use App\Services\IterationEventBuffer\PerceptronLimitedEpochEventBuffer;
use Illuminate\Support\Facades\Event;
use Tests\TestCase;

class IterationEventBufferTest extends TestCase
{
    public function test_iterations_are_sent_as_a_single_batch(): void
    {
        Event::fake();
        $buffer = new PerceptronIterationEventBuffer('session', 'training');

        $buffer->addIteration(1, 0, 0.5, []);
        $buffer->addIteration(1, 1, 0.25, []);
        $buffer->flush();

        Event::assertDispatched(PerceptronTrainingIteration::class, function (PerceptronTrainingIteration $event): bool {
            return count($event->iterations) === 2;
        });
    }

    public function test_limited_buffer_sends_the_latest_non_selected_epoch_on_final_flush(): void
    {
        Event::fake();
        $buffer = new PerceptronLimitedEpochEventBuffer('session', 'training', 2);

        $buffer->addIteration(1, 0, 0.5, []);
        $buffer->addIteration(2, 0, 0.25, []);
        $buffer->addIteration(2, 1, 0.125, []);
        $buffer->flush();

        Event::assertDispatchedTimes(PerceptronTrainingIteration::class, 2);
        Event::assertDispatched(PerceptronTrainingIteration::class, function (PerceptronTrainingIteration $event): bool {
            return count($event->iterations) === 2
                && $event->iterations[0]['epoch'] === 2;
        });
    }

    public function test_non_finite_values_are_normalized_before_broadcasting(): void
    {
        $event = new PerceptronTrainingIteration([
            [
                'epoch' => 1,
                'exampleIndex' => 0,
                'error' => NAN,
                'weights' => [[[INF]]],
            ],
        ], 'session', 'training');

        $payload = $event->broadcastWith();

        $this->assertNull($payload['iterations'][0]['error']);
        $this->assertNull($payload['iterations'][0]['weights'][0][0][0]);
        $this->assertJson(json_encode($payload, JSON_THROW_ON_ERROR));
    }
}