translations_api( string $type, array|object $args = null )

function translations_api( $type, $args = null ) {
	include( ABSPATH . WPINC . '/version.php' ); // include an unmodified $wp_version

	if ( ! in_array( $type, array( 'plugins', 'themes', 'core' ) ) ) {
		return new WP_Error( 'invalid_type', __( 'Invalid translation type.' ) );
	}

	/**
	 * Allows a plugin to override the ClassicPress.net Translation Installation API entirely.
	 *
	 * @since WP-4.0.0
	 *
	 * @param bool|array  $result The result object. Default false.
	 * @param string      $type   The type of translations being requested.
	 * @param object      $args   Translation API arguments.
	 */
	$res = apply_filters( 'translations_api', false, $type, $args );

	if ( false === $res ) {
		$stats = array(
			'locale'  => get_locale(),
			'version' => $args['version'], // Version of plugin, theme or core
		);
		$options = array(
			'timeout' => 3,
			'method'  => 'POST',
		);
		if ( 'core' === $type ) {
			// Get ClassicPress core translations from the ClassicPress.net API.
			$stats['cp_version'] = $cp_version;
			$options['method'] = 'GET';
			$url = add_query_arg(
				$stats,
				'https://api-v1.classicpress.net/translations/core/1.0.0/translations.json'
			);
			$request = wp_remote_request( $url, $options );
		} else {
			// Get plugin and theme translations from the WP.org API.
			$stats['wp_version'] = $wp_version;
			$options['body'] = $stats;
			$options['body']['slug'] = $args['slug']; // Plugin or theme slug
			$url = 'https://api.wordpress.org/translations/' . $type . '/1.0/';
			$request = wp_remote_request( $url, $options );
		}

		if ( is_wp_error( $request ) ) {
			trigger_error(
				sprintf(
					/* translators: %s: support forums URL */
					__( 'An unexpected error occurred. Something may be wrong with ClassicPress.net or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
					__( 'https://forums.classicpress.net/c/support' )
				) . ' ' . __( '(ClassicPress could not establish a secure connection to ClassicPress.net. Please contact your server administrator.)' ),
				headers_sent() || WP_DEBUG ? E_USER_WARNING : E_USER_NOTICE
			);

			// Retry request
			$request = wp_remote_request( $url, $options );
		}

		if ( is_wp_error( $request ) ) {
			$res = new WP_Error( 'translations_api_failed',
				sprintf(
					/* translators: %s: support forums URL */
					__( 'An unexpected error occurred. Something may be wrong with ClassicPress.net or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
					__( 'https://forums.classicpress.net/c/support' )
				),
				$request->get_error_message()
			);
		} else {
			$res = json_decode( wp_remote_retrieve_body( $request ), true );
			if ( ! is_object( $res ) && ! is_array( $res ) ) {
				$res = new WP_Error( 'translations_api_failed',
					sprintf(
						/* translators: %s: support forums URL */
						__( 'An unexpected error occurred. Something may be wrong with ClassicPress.net or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
						__( 'https://forums.classicpress.net/c/support' )
					),
					wp_remote_retrieve_body( $request )
				);
			}
		}
	}

	/**
	 * Filters the Translation Installation API response results.
	 *
	 * @since WP-4.0.0
	 *
	 * @param object|WP_Error $res  Response object or WP_Error.
	 * @param string          $type The type of translations being requested.
	 * @param object          $args Translation API arguments.
	 */
	return apply_filters( 'translations_api_result', $res, $type, $args );
}