// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module bluetooth.mojom;

import "device/bluetooth/public/mojom/device.mojom";

// Possible errors sent as a response by Adapter.ConnectToDevice on a Device
// connection request.
enum ConnectResult {
  SUCCESS,
  AUTH_CANCELED,
  AUTH_FAILED,
  AUTH_REJECTED,
  AUTH_TIMEOUT,
  FAILED,
  INPROGRESS,
  UNKNOWN,
  UNSUPPORTED_DEVICE,
  DEVICE_NO_LONGER_IN_RANGE,
};

struct AdapterInfo {
  string address;
  string name;
  bool initialized;
  bool present;
  bool powered;
  bool discoverable;
  bool discovering;
};

interface DiscoverySession {
  // Returns true if the session is active, false otherwise. If false, the
  // adapter might still be discovering as there might still be other active
  // sessions; this just means that this instance no longer has a say in
  // whether or not discovery should continue. In this case, a new
  // DiscoverySession should be started to make sure that device discovery
  // continues.
  IsActive() => (bool active);

  // Requests this discovery session instance to stop. If this instance is
  // active, the session will stop. After a successful invocation, the
  // adapter may or may not stop device discovery, depending on whether or not
  // other active discovery sessions are present. Users are highly encouraged
  // to call this method to end a discovery session, instead of relying on
  // disconnecting the message pipe, so that they can respond to the result.
  // Returns true on success. Returns false if this session is inactive or an
  // error occurs while stopping the session.
  Stop() => (bool success);
};

interface Adapter {
  // Creates a GATT connection to the device with |address| and returns a
  // Device if the connection was succesful. The GATT connection is tied to the
  // the lifetime of the Device message pipe.
  ConnectToDevice(string address) => (ConnectResult result, Device? device);

  // Retrieves the list of the devices known by the adapter including Connected
  // Devices, GATT Connected Devices, Paired Devices and Devices discovered
  // during a classic or low-energy scan.
  GetDevices() => (array<DeviceInfo> devices);

  // Gets basic information about the adapter.
  GetInfo() => (AdapterInfo info);

  // Sets the client that listens for the adapter's events.
  SetClient(AdapterClient client);

  // Requests the adapter to start a new discovery session. Returns null if
  // session not created successfully.
  StartDiscoverySession() => (DiscoverySession? session);
};

interface AdapterClient {
  // Called when the presence of the adapter changes.
  PresentChanged(bool present);

  // Called when the radio power state of the adapter changes.
  PoweredChanged(bool powered);

  // Called when the discoverability state of the adapter changes.
  DiscoverableChanged(bool discoverable);

  // Called when the discovering state of the adapter changes.
  DiscoveringChanged(bool discovering);

  // Called the first time a device is discovered.
  DeviceAdded(DeviceInfo device);

  // Called when one of the following properties of a device changes:
  //   Address, appearance, Bluetooth class, Inquiry RSSI, Inquiry TX Power,
  //   Service UUIDs, Connectionable state, Connection state, Pairing state,
  //   Trustable state.
  // Generally called for each advertisement packet recevied, but this is not
  // guaranteed on ChromeOS or Linux. Because the RSSI is always changing,
  // it's very likely this will be called for each advertising packet.
  DeviceChanged(DeviceInfo device);

  // Called after the device hasn't been seen for 3 minutes.
  DeviceRemoved(DeviceInfo device);
};