<?php

declare(strict_types=1);

namespace KTXC\Resource;

use KTXC\Server;
use KTXF\Resource\Provider\ProviderInterface;

/**
 * Provider Registry
 * 
 * Manages registration and resolution of authentication providers.
 */
class ProviderManager
{
    private array $registeredProviders = [];
    private array $resolvedProviders = [];

    public function __construct(
    ) {}

    /**
     * Register an authentication provider (called from module boot)
     *
     * @param string $type Provider type (e.g., 'authentication', 'storage', 'notification')
     * @param string $identifier Provider ID (e.g., 'default', 'oidc', 'totp')
     * @param string $class Fully qualified class name
     */
    public function register(string $type, string $identifier, string $class): void
    {
        $this->registeredProviders[$type][$identifier] = $class;
    }

    /**
     * Unregister a provider
     */
    public function unregister(string $type, string $identifier): void
    {
        unset($this->registeredProviders[$type][$identifier]);
        unset($this->resolvedProviders[$type][$identifier]);
    }

    /**
     * Resolve a provider by ID
     */
    public function resolve(string $type, string $identifier): ?ProviderInterface
    {
        if (isset($this->resolvedProviders[$type][$identifier])) {
            return $this->resolvedProviders[$type][$identifier];
        }

        if (!isset($this->registeredProviders[$type][$identifier])) {
            return null;
        }

        try {
            $provider = Server::runtimeContainer()->get($this->registeredProviders[$type][$identifier]);
            $this->resolvedProviders[$type][$identifier] = $provider;
            return $provider;
        } catch (\Exception $e) {
            error_log("Failed to resolve provider {$identifier}: " . $e->getMessage());
            return null;
        }
    }

    /**
     * Resolve multiple providers
     *
     * @param array|null $filter Optional list of provider IDs to return
     * @return array<string, ProviderInterface>
     */
    public function providers(string $type, ?array $filter = null): array
    {
        $requestedProviders = $filter ?? array_keys($this->registeredProviders[$type] ?? []);
        $result = [];

        foreach ($requestedProviders as $identifier) {
            $provider = $this->resolve($type, $identifier);
            if ($provider !== null) {
                $result[$identifier] = $provider;
            }
        }

        return $result;
    }

}