// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module ash.babelorca.mojom;

import "sandbox/policy/mojom/sandbox.mojom";

// Represents a segment of the sender transcription. Should be kept in sync with
// //chromeos/ash/components/boca/babelorca/proto/babel_orca_message.proto
struct TranscriptPart {
  int64 transcript_id;
  int64 text_index;
  string text;
  bool is_final;
  string language;
};

// Represents BabelOrcaMessage sent from the captions sender in addition to the
// sender email for verification. Should be kept in sync with
// //chromeos/ash/components/boca/babelorca/proto/babel_orca_message.proto
struct BabelOrcaMessage {
  string? sender_email;
  string session_id;
  int64 init_timestamp_ms;
  int64 order;
  TranscriptPart? previous_transcript;
  TranscriptPart current_transcript;
};

// Stream status when the server ends the connection.
struct StreamStatus {
  int32 code;
  string message;
};

// Current parsing state. Parser won't process new data for a stream that has
// ParsingState not equal to kOk.
enum ParsingState {
  kOk,
  kError,
  kClosed,
};

// Sandboxed service to parse received Tachyon data stream, should be used only
// by BabelOrca clients.
[ServiceSandbox=sandbox.mojom.Sandbox.kService]
interface TachyonParsingService {
  // Parse the stream data. `messages` can be empty if no data could be parsed
  // either because of error, if data is incomplete, or the received data is
  // not a `BabelOrcaMessage`. `stream_status` is received at the end of the
  // stream indicating that the stream is closed, `state` will be `kClosed` in
  // this case.
  Parse(string stream_data) => (ParsingState state,
                                array<BabelOrcaMessage> messages,
                                StreamStatus? stream_status);
};