<?php

declare(strict_types=1);

namespace App\Framework\Discovery\ValueObjects;

use ArrayIterator;
use Countable;
use IteratorAggregate;

/**
 * Type-safe collection of discovered attributes
 */
final readonly class AttributeCollection implements IteratorAggregate, Countable
{
    /** @var array<DiscoveredAttribute> */
    private array $attributes;

    public function __construct(DiscoveredAttribute ...$attributes)
    {
        $this->attributes = $attributes;
    }

    public function add(DiscoveredAttribute $attribute): self
    {
        $newAttributes = [...$this->attributes, $attribute];

        return new self(...$newAttributes);
    }

    /**
     * @return ArrayIterator<int, DiscoveredAttribute>
     */
    public function getIterator(): ArrayIterator
    {
        return new ArrayIterator($this->attributes);
    }

    public function count(): int
    {
        return count($this->attributes);
    }

    public function isEmpty(): bool
    {
        return empty($this->attributes);
    }

    /**
     * Filter by attribute class
     */
    public function filterByAttributeClass(string $attributeClass): self
    {
        $filtered = array_filter(
            $this->attributes,
            fn (DiscoveredAttribute $attr) => $attr->attributeClass === $attributeClass
        );

        return new self(...$filtered);
    }

    /**
     * Filter by target type
     */
    public function filterByTarget(AttributeTarget $target): self
    {
        $filtered = array_filter(
            $this->attributes,
            fn (DiscoveredAttribute $attr) => $attr->target === $target
        );

        return new self(...$filtered);
    }

    /**
     * Get all class attributes
     */
    public function getClassAttributes(): self
    {
        return $this->filterByTarget(AttributeTarget::TARGET_CLASS);
    }

    /**
     * Get all method attributes
     */
    public function getMethodAttributes(): self
    {
        return $this->filterByTarget(AttributeTarget::METHOD);
    }

    /**
     * Convert to array for backwards compatibility
     * @deprecated Use object methods instead
     * @return array<string, array<array<string, mixed>>>
     */
    public function toLegacyArray(): array
    {
        $result = [];

        foreach ($this->attributes as $attribute) {
            $attributeClass = $attribute->attributeClass;

            if (! isset($result[$attributeClass])) {
                $result[$attributeClass] = [];
            }

            $result[$attributeClass][] = $attribute->toArray();
        }

        return $result;
    }

    /**
     * @return array<DiscoveredAttribute>
     */
    public function toArray(): array
    {
        return $this->attributes;
    }
}