@startuml
!theme mono

title STT Service - 음성녹음시작 내부 시퀀스

participant "RecordingController" as Controller
participant "RecordingService" as Service
participant "RecordingRepository" as Repository
participant "AzureSpeechClient" as AzureClient
database "STT DB" as DB
database "Azure Blob Storage<<E>>" as BlobStorage
queue "Azure Event Hubs<<E>>" as EventHub

== MeetingStarted 이벤트 수신 ==

EventHub -> Controller: MeetingStarted 이벤트 수신\n(meetingId, sessionId)
activate Controller

Controller -> Service: prepareRecording(meetingId, sessionId)
activate Service

Service -> Service: 녹음 세션 검증
note right
  - 중복 녹음 방지 체크
  - meetingId 유효성 검증
end note

Service -> Repository: createRecording(meetingId, sessionId)
activate Repository

Repository -> DB: INSERT INTO recordings\n(recording_id, meeting_id, session_id,\nstatus='READY', created_at)
activate DB
DB --> Repository: recordingId 반환
deactivate DB

Repository --> Service: RecordingEntity 반환
deactivate Repository

== Azure Speech Service 초기화 ==

Service -> AzureClient: initializeRecognizer(recordingId, sessionId)
activate AzureClient

AzureClient -> AzureClient: 음성 인식기 설정
note right
  - 언어: ko-KR
  - 샘플레이트: 16kHz
  - 화자 식별 활성화
  - 실시간 스트리밍 모드
end note

AzureClient -> BlobStorage: 녹음 파일 저장 경로 생성\n(path: recordings/{meetingId}/{sessionId}.wav)
activate BlobStorage
BlobStorage --> AzureClient: 저장 경로 URL 반환
deactivate BlobStorage

AzureClient --> Service: RecognizerConfig 반환
deactivate AzureClient

== 녹음 상태 업데이트 ==

Service -> Repository: updateRecordingStatus(recordingId, "RECORDING")
activate Repository

Repository -> DB: UPDATE recordings\nSET status='RECORDING',\nstarted_at=NOW(),\nstorage_path='{blobUrl}'\nWHERE recording_id='{recordingId}'
activate DB
DB --> Repository: 업데이트 완료
deactivate DB

Repository --> Service: 업데이트 완료
deactivate Repository

Service --> Controller: RecordingResponse(recordingId, status, storagePath)
deactivate Service

Controller --> EventHub: RecordingStarted 이벤트 발행\n(recordingId, meetingId, status)
deactivate Controller

note over Controller, EventHub
처리 시간:
- DB 녹음 생성: ~100ms
- Azure 인식기 초기화: ~500ms
- Blob 경로 생성: ~200ms
- 총 처리 시간: ~800ms
end note

@enduml