public function activate_license() {

		if ( ! isset( $_POST['pum_settings'] ) ) {
			return;
		}
		if ( ! isset( $_POST['pum_settings'][ $this->item_shortname . '_license_key' ] ) ) {
			return;
		}

		// Don't activate a key when deactivating a different key
		if ( ! empty( $_POST['pum_license_deactivate'] ) ) {
			return;
		}

		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		$details = get_option( $this->item_shortname . '_license_active' );

		if ( is_object( $details ) && 'valid' === $details->license ) {
			return;
		}

		$license = sanitize_text_field( $_POST['pum_settings'][ $this->item_shortname . '_license_key' ] );

		if ( empty( $license ) && empty( $_POST['pum_license_activate'][ $this->item_shortname . '_license_key' ] ) ) {
			return;
		}

		// Data to send to the API
		$api_params = array(
			'edd_action' => 'activate_license',
			'license'    => $license,
			'item_name'  => urlencode( $this->item_name ),
			'item_id'    => $this->item_id,
			'url'        => home_url(),
		);

		// Call the API
		$response = wp_remote_post( $this->api_url, array(
			'timeout'   => 15,
			'sslverify' => false,
			'body'      => $api_params,
		) );

		// Make sure there are no errors
		if ( is_wp_error( $response ) ) {
			return;
		}

		// Tell WordPress to look for updates
		set_site_transient( 'update_plugins', null );

		// Decode license data
		$license_data = json_decode( wp_remote_retrieve_body( $response ) );

		update_option( $this->item_shortname . '_license_active', $license_data );
	}