Automattic/php-push

<?php
declare( strict_types = 1 );

class APNSConfiguration {

    public const APNS_ENVIRONMENT_PRODUCTION = 'production';
    public const APNS_ENDPOINT_PRODUCTION    = 'https://api.push.apple.com/3/device/';

    public const APNS_ENVIRONMENT_SANDBOX = 'sandbox';
    public const APNS_ENDPOINT_SANDBOX    = 'https://api.development.push.apple.com/3/device/';

    /** @var APNSCredentials */
    private $credentials;

    /** @var string|null */
    private $user_agent = null;

    /** @var string */
    private $environment;

    /** @var string|null */
    private $current_token = null;

    /** @var int */
    private $expires = 0;

    /**
     * How frequently to refresh the auth token. Specified in seconds.
     *
     * @var int
     */
    private $token_refresh_interval = 1800;

    /** @var APNSTokenFactory */
    private $token_factory;

    protected function __construct( APNSCredentials $credentials, string $environment, ?APNSTokenFactory $factory ) {
        $this->credentials   = $credentials;
        $this->environment   = $environment;
        $this->token_factory = $factory ?? new APNSDefaultTokenFactory();
    }

    public static function production( APNSCredentials $credentials, ?APNSTokenFactory $factory = null ): self {
        return new APNSConfiguration( $credentials, self::APNS_ENVIRONMENT_PRODUCTION, $factory );
    }

    public static function sandbox( APNSCredentials $credentials, ?APNSTokenFactory $factory = null ): self {
        return new APNSConfiguration( $credentials, self::APNS_ENVIRONMENT_SANDBOX, $factory );
    }

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

    public function get_provider_token(): string {

        if ( ! is_null( $this->current_token ) && $this->expires > time() ) {
            return $this->current_token;
        }

        $current_token = $this->token_factory->get_token(
            $this->credentials->get_team_id(),
            $this->credentials->get_key_id(),
            $this->credentials->get_key_bytes()
        );

        $this->expires       = time() + $this->token_refresh_interval;
        $this->current_token = $current_token;

        return $current_token;
    }

    public function get_user_agent(): ?string {
        return $this->user_agent;
    }

    public function set_user_agent( string $user_agent ): self {
        $this->user_agent = $user_agent;
        return $this;
    }

    public function get_token_refresh_interval(): int {
        return $this->token_refresh_interval;
    }

    // Must be between 20 and 60 minutes:
    // Refresh your token no more than once every 20 minutes and no less than once every 60 minutes. APNs rejects any request whose token contains a timestamp that is more than one hour old. Similarly, APNs reports an error if you recreate your tokens more than once every 20 minutes.
    // Source: https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/establishing_a_token-based_connection_to_apns
    public function set_token_refresh_interval( int $interval ): self {

        if ( $interval < 1260 ) {
            throw new InvalidArgumentException( 'Invalid Token Refresh interval: ' . $interval . '. It must be greater than 21 minutes and less than 59 minutes (specified in seconds)' );
        }

        if ( $interval > 3540 ) {
            throw new InvalidArgumentException( 'Invalid Token Refresh interval: ' . $interval . '. It must be less than 59 minutes and greater than 21 minutes (specified in seconds)' );
        }

        $this->token_refresh_interval = $interval;

        return $this;
    }

    public function get_endpoint(): string {
        if ( self::APNS_ENVIRONMENT_PRODUCTION === $this->environment ) {
            return self::APNS_ENDPOINT_PRODUCTION;
        }

        if ( self::APNS_ENVIRONMENT_SANDBOX === $this->environment ) {
            return self::APNS_ENDPOINT_SANDBOX;
        }

        throw new OutOfBoundsException( 'Unable to determine endpoint for environment' );
    }
}