// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

library fuchsia.castconfig;

using fuchsia.mem;

/// Error codes for the Watch operation.
enum ErrorCode {
    /// Error when there is no cast config available.
    NO_CAST_CONFIG = 1;
    /// Generic error.
    INTERNAL = 2;
};

/// Interface that provides cast config data.
[Discoverable]
protocol Provider {
    /// Requests a buffer containing cast config data.
    /// This call implements the Hanging Get protocol as detailed in
    /// https://fuchsia.dev/fuchsia-src/development/api/fidl.md#delay-responses-using-hanging-gets
    ///
    /// All error cases are terminal, clients should not retry on error.
    Watch() -> (fuchsia.mem.Buffer config) error ErrorCode;

    /// Notifies the config provider of the config status.
    ///
    /// `processed`: `true` if successfully recieved and processed
    /// `retry`: If `processed` is `false` config provider determines if a retry
    ///  is appropriate.
    Notify(bool processed) -> (bool retry);
};