<?php

declare(strict_types=1);

namespace Phpml\Tests\NeuralNetwork;

use Phpml\Exception\InvalidArgumentException;
use Phpml\NeuralNetwork\Layer;
use Phpml\NeuralNetwork\Node\Bias;
use Phpml\NeuralNetwork\Node\Neuron;
use PHPUnit\Framework\TestCase;
use stdClass;

class LayerTest extends TestCase
{
    public function testLayerInitialization(): void
    {
        $layer = new Layer();

        self::assertEquals([], $layer->getNodes());
    }

    public function testLayerInitializationWithDefaultNodesType(): void
    {
        $layer = new Layer($number = 5);

        self::assertCount($number, $layer->getNodes());
        foreach ($layer->getNodes() as $node) {
            self::assertInstanceOf(Neuron::class, $node);
        }
    }

    public function testLayerInitializationWithExplicitNodesType(): void
    {
        $layer = new Layer($number = 5, $class = Bias::class);

        self::assertCount($number, $layer->getNodes());
        foreach ($layer->getNodes() as $node) {
            self::assertInstanceOf($class, $node);
        }
    }

    public function testThrowExceptionOnInvalidNodeClass(): void
    {
        $this->expectException(InvalidArgumentException::class);
        new Layer(1, stdClass::class);
    }

    public function testAddNodesToLayer(): void
    {
        $layer = new Layer();
        $layer->addNode($node1 = new Neuron());
        $layer->addNode($node2 = new Neuron());

        self::assertEquals([$node1, $node2], $layer->getNodes());
    }
}