import os
from pathlib import Path
from dotenv import load_dotenv

# Load environment variables from .env file
load_dotenv()

# Project root - can be overridden by environment variable
PROJECT_ROOT = Path(
    os.getenv("PROJECT_ROOT", Path(__file__).parent.parent.parent)
).resolve()

# Directory paths
SPEAKER_DATA_BASE_DIR = Path(
    os.getenv("SPEAKER_DATA_BASE_DIR", str(PROJECT_ROOT / "speaker_data"))
)
SPEAKER_SAMPLES_DIR = Path(
    os.getenv("SPEAKER_SAMPLES_DIR", str(SPEAKER_DATA_BASE_DIR / "speaker_samples"))
)
SPEAKERS_YAML_FILE = Path(
    os.getenv("SPEAKERS_YAML_FILE", str(SPEAKER_DATA_BASE_DIR / "speakers.yaml"))
)

# TTS temporary output path (used by DialogProcessorService)
TTS_TEMP_OUTPUT_DIR = Path(
    os.getenv("TTS_TEMP_OUTPUT_DIR", str(PROJECT_ROOT / "tts_temp_outputs"))
)

# Final dialog output path (used by Dialog router and served by main app)
# These are stored within the 'backend' directory to be easily servable.
DIALOG_OUTPUT_PARENT_DIR = PROJECT_ROOT / "backend"
DIALOG_GENERATED_DIR = Path(
    os.getenv(
        "DIALOG_GENERATED_DIR", str(DIALOG_OUTPUT_PARENT_DIR / "tts_generated_dialogs")
    )
)

# Alias for clarity and backward compatibility
DIALOG_OUTPUT_DIR = DIALOG_GENERATED_DIR

# Server configuration
HOST = os.getenv("HOST", "0.0.0.0")
PORT = int(os.getenv("PORT", "8000"))
RELOAD = os.getenv("RELOAD", "true").lower() == "true"

# CORS configuration: determine allowed origins based on env & frontend binding
_cors_env = os.getenv("CORS_ORIGINS", "")
_frontend_host = os.getenv("FRONTEND_HOST")
_frontend_port = os.getenv("FRONTEND_PORT")

# If the dev server is bound to 0.0.0.0 (all interfaces), allow all origins
if _frontend_host == "0.0.0.0":  # dev convenience when binding wildcard
    CORS_ORIGINS = ["*"]
elif _cors_env:
    # parse comma-separated origins, strip whitespace
    CORS_ORIGINS = [origin.strip() for origin in _cors_env.split(",") if origin.strip()]
else:
    # default to allow all origins in development
    CORS_ORIGINS = ["*"]

# Auto-include specific frontend origin when not using wildcard CORS
if CORS_ORIGINS != ["*"] and _frontend_host and _frontend_port:
    _frontend_origin = f"http://{_frontend_host.strip()}:{_frontend_port.strip()}"
    if _frontend_origin not in CORS_ORIGINS:
        CORS_ORIGINS.append(_frontend_origin)

# Device configuration
DEVICE = os.getenv("DEVICE", "auto")
 
# Concurrency configuration
# Max number of concurrent TTS generation tasks per dialog request
TTS_MAX_CONCURRENCY = int(os.getenv("TTS_MAX_CONCURRENCY", "3"))

# Model idle eviction configuration
# Enable/disable idle-based model eviction
MODEL_EVICTION_ENABLED = os.getenv("MODEL_EVICTION_ENABLED", "true").lower() == "true"
# Unload model after this many seconds of inactivity (0 disables eviction)
MODEL_IDLE_TIMEOUT_SECONDS = int(os.getenv("MODEL_IDLE_TIMEOUT_SECONDS", "900"))
# How often the reaper checks for idleness
MODEL_IDLE_CHECK_INTERVAL_SECONDS = int(os.getenv("MODEL_IDLE_CHECK_INTERVAL_SECONDS", "60"))

# Ensure directories exist
SPEAKER_SAMPLES_DIR.mkdir(parents=True, exist_ok=True)
TTS_TEMP_OUTPUT_DIR.mkdir(parents=True, exist_ok=True)
DIALOG_GENERATED_DIR.mkdir(parents=True, exist_ok=True)