<?php

declare(strict_types=1);

namespace KTXF\Event;

/**
 * Base event class for the event bus system
 */
class Event
{
    private bool $propagationStopped = false;
    private readonly array $context;
    private readonly float $timestamp;
    private readonly string $identifier;

    public function __construct(
        private readonly string $label,
        array $context = [],
        private readonly ?string $tenantIdentifier = null,
        private readonly ?string $actorIdentity = null,
    ) {
        self::validateContext($context);

        $this->context = $context;
        $this->timestamp = microtime(true);
        $this->identifier = bin2hex(random_bytes(16));
    }

    /**
     * Get the event label
     */
    public function label(): string
    {
        return $this->label;
    }

    /**
     * Get a context value by key
     */
    public function get(string $key, mixed $default = null): mixed
    {
        return $this->context[$key] ?? $default;
    }

    /**
     * Check if a context key exists
     */
    public function has(string $key): bool
    {
        return array_key_exists($key, $this->context);
    }

    /**
     * Get the event context
     */
    public function context(): array
    {
        return $this->context;
    }

    /**
     * Get all event context
     */
    public function all(): array
    {
        return $this->context;
    }

    /**
     * Get the event timestamp
     */
    public function timestamp(): float
    {
        return $this->timestamp;
    }

    public function identifier(): string
    {
        return $this->identifier;
    }

    /**
     * Stop event propagation to subsequent listeners
     */
    public function stopPropagation(): void
    {
        $this->propagationStopped = true;
    }

    /**
     * Check if propagation is stopped
     */
    public function isPropagationStopped(): bool
    {
        return $this->propagationStopped;
    }

    /**
     * Get tenant ID for multi-tenant context
     */
    public function tenantIdentifier(): ?string
    {
        return $this->tenantIdentifier;
    }

    /**
     * Get the identity of the actor who triggered the event
     */
    public function actorIdentity(): ?string
    {
        return $this->actorIdentity;
    }

    private static function validateContext(array $context): void
    {
        foreach ($context as $value) {
            if (is_array($value)) {
                self::validateContext($value);
                continue;
            }
            if ($value !== null && !is_scalar($value)) {
                throw new \InvalidArgumentException(
                    'Event context must contain only scalar, null, or array values.',
                );
            }
        }
    }
}