ic closely matches the one in plugin_basename().
		// $wp_plugin_paths contains normalized paths.
		$file = wp_normalize_path( $gateway_class_filename );

		arsort( $wp_plugin_paths );
		// Account for symlinks in the plugin paths.
		foreach ( $wp_plugin_paths as $dir => $realdir ) {
			if ( str_starts_with( $file, $realdir ) ) {
				$gateway_class_filename = $dir . substr( $gateway_class_filename, strlen( $realdir ) );
			}
		}

		// Test for regular plugins.
		if ( str_starts_with( $gateway_class_filename, wp_normalize_path( WP_PLUGIN_DIR ) ) ) {
			// For now, all plugins are considered WordPress.org plugins.
			return PaymentsProviders::EXTENSION_TYPE_WPORG;
		}

		// Test for must-use plugins.
		if ( str_starts_with( $gateway_class_filename, wp_normalize_path( WPMU_PLUGIN_DIR ) ) ) {
			return PaymentsProviders::EXTENSION_TYPE_MU_PLUGIN;
		}

		// Check if it is part of a theme.
		if ( is_array( $wp_theme_directories ) ) {
			foreach ( $wp_theme_directories as $dir ) {
				// Check if the class file is in a theme directory.
				if ( str_starts_with( $gateway_class_filename, $dir ) ) {
					return PaymentsProviders::EXTENSION_TYPE_THEME;
				}
			}
		}

		// Default to an unknown type.
		return PaymentsProviders::EXTENSION_TYPE_UNKNOWN;
	}

	/**
	 * Extract the slug from a given path.
	 *
	 * It can be a directory or file path.
	 * This should be a relative path since the top-level directory or file name will be used as the slug.
	 *
	 * @param string $path The path to extract the slug from.
	 *
	 * @return string The slug extracted from the path.
	 */
	private function extract_slug_from_path( string $path ): string {
		$path = trim( $path );
		$path = trim( $path, DIRECTORY_SEPARATOR );

		// If the path is just a file name, use it as the slug.
		if ( false === strpos( $path, DIRECTORY_SEPARATOR ) ) {
			return Utils::trim_php_file_extension( $path );
		}

		$parts = explode( DIRECTORY_SEPARATOR, $path );
		// Bail if we couldn't get the parts.
		if ( ! is_array( $parts ) ) {
			return '';
		}

		return reset( $parts );
	}
}