# -----------------------------------------------------------------------------
# Engine .env example (safe template)
# Notes:
# - Never commit real API keys.
# - Start with defaults below, then tune from logs.
# -----------------------------------------------------------------------------

# Server
HOST=0.0.0.0
PORT=8000
# EXTERNAL_IP=1.2.3.4

# Backend bridge (optional)
BACKEND_URL=http://127.0.0.1:8100
BACKEND_TIMEOUT_SEC=10
HISTORY_DEFAULT_USER_ID=1

# Audio
SAMPLE_RATE=16000
# 20ms is recommended for VAD stability and latency.
# 100ms works but usually worsens start-of-speech accuracy.
CHUNK_SIZE_MS=20
DEFAULT_CODEC=pcm
MAX_AUDIO_BUFFER_SECONDS=30

# VAD / EOU
VAD_TYPE=silero
VAD_MODEL_PATH=data/vad/silero_vad.onnx
# Higher = stricter speech detection (fewer false positives, more misses).
VAD_THRESHOLD=0.5
# Require this much continuous speech before utterance can be valid.
VAD_MIN_SPEECH_DURATION_MS=100
# Silence duration required to finalize one user turn.
VAD_EOU_THRESHOLD_MS=800

# LLM
OPENAI_API_KEY=your_openai_api_key_here
# Optional for OpenAI-compatible providers.
# OPENAI_API_URL=https://api.openai.com/v1
LLM_MODEL=gpt-4o-mini
LLM_TEMPERATURE=0.7

# TTS
# edge: no API key needed
# openai_compatible: compatible with SiliconFlow-style endpoints
TTS_PROVIDER=openai_compatible
TTS_VOICE=anna
TTS_SPEED=1.0

# SiliconFlow (used by TTS and/or ASR when provider=openai_compatible)
SILICONFLOW_API_KEY=your_siliconflow_api_key_here
SILICONFLOW_TTS_MODEL=FunAudioLLM/CosyVoice2-0.5B
SILICONFLOW_ASR_MODEL=FunAudioLLM/SenseVoiceSmall

# ASR
ASR_PROVIDER=openai_compatible
# Interim cadence and minimum audio before interim decode.
ASR_INTERIM_INTERVAL_MS=500
ASR_MIN_AUDIO_MS=300
# ASR start gate: ignore micro-noise, then commit to one turn once started.
ASR_START_MIN_SPEECH_MS=160
# Pre-roll protects beginning phonemes.
ASR_PRE_SPEECH_MS=240
# Tail silence protects ending phonemes.
ASR_FINAL_TAIL_MS=120

# Duplex behavior
DUPLEX_ENABLED=true
# DUPLEX_GREETING=Hello! How can I help you today?
DUPLEX_SYSTEM_PROMPT=You are a helpful, friendly voice assistant. Keep your responses concise and conversational.

# Barge-in (user interrupting assistant)
# Min user speech duration needed to interrupt assistant audio.
BARGE_IN_MIN_DURATION_MS=200
# Allowed silence during potential barge-in (ms) before reset.
BARGE_IN_SILENCE_TOLERANCE_MS=60

# Logging
LOG_LEVEL=INFO
# json is better for production/observability; text is easier locally.
LOG_FORMAT=json

# WebSocket behavior
INACTIVITY_TIMEOUT_SEC=60
HEARTBEAT_INTERVAL_SEC=50
WS_PROTOCOL_VERSION=v1
# WS_API_KEY=replace_with_shared_secret
WS_REQUIRE_AUTH=false

# CORS / ICE (JSON strings)
CORS_ORIGINS=["http://localhost:3000","http://localhost:8080"]
ICE_SERVERS=[{"urls":"stun:stun.l.google.com:19302"}]