import os
os.environ["NUMEXPR_MAX_THREADS"] = "12"

from fastapi import FastAPI, HTTPException, Depends, Body, status, Response
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse, FileResponse
from fastapi.staticfiles import StaticFiles
from fastapi.security import OAuth2PasswordRequestForm
from contextlib import asynccontextmanager

from typing import Dict, Any
import logging
from logging.handlers import RotatingFileHandler
from datetime import timedelta
import pathlib

from modules.configuration import APP_CONFIG

def initLogging():
    # Get log level from config (default to INFO if not found)
    logLevelName = APP_CONFIG.get("APP_LOGGING_LOG_LEVEL", "WARNING")
    logLevel = getattr(logging, logLevelName)

    # Configure handlers based on config
    handlers = []

    # Add console handler if enabled
    if APP_CONFIG.get("APP_LOGGING_CONSOLE_ENABLED", True):
        consoleHandler = logging.StreamHandler()
        handlers.append(consoleHandler)

    # Add file handler if enabled
    if APP_CONFIG.get("APP_LOGGING_FILE_ENABLED", True):
        logFile = APP_CONFIG.get("APP_LOGGING_LOG_FILE", "app.log")
        rotationSize = int(APP_CONFIG.get("APP_LOGGING_ROTATION_SIZE", 10485760))  # Default: 10MB
        backupCount = int(APP_CONFIG.get("APP_LOGGING_BACKUP_COUNT", 5))
        
        fileHandler = RotatingFileHandler(
            logFile, 
            maxBytes=rotationSize, 
            backupCount=backupCount
        )
        handlers.append(fileHandler)

    # Configure the logger
    logging.basicConfig(
        level=logLevel,
        format=APP_CONFIG.get("APP_LOGGING_FORMAT", "%(asctime)s - %(levelname)s - %(name)s - %(message)s"),
        datefmt=APP_CONFIG.get("APP_LOGGING_DATE_FORMAT", "%Y-%m-%d %H:%M:%S"),
        handlers=handlers
    )

    # Silence noisy third-party libraries - use the same level as the root logger
    noisyLoggers = ["httpx", "urllib3", "asyncio", "fastapi.security.oauth2"]
    for loggerName in noisyLoggers:
        logging.getLogger(loggerName).setLevel(logLevel)


# Initialize logging
initLogging()
logger = logging.getLogger(__name__)
instanceLabel = APP_CONFIG.get("APP_ENV_LABEL")

# Import auth module
from modules.auth import (
    createAccessToken,
    getCurrentActiveUser, 
    getUserContext,
    ACCESS_TOKEN_EXPIRE_MINUTES
)

# Import models - import generically for INITIALIZATION
import modules.gatewayModel as gatewayModel
from modules.gatewayInterface import getGatewayInterface
gateway = getGatewayInterface()


# Define lifespan context manager for application startup/shutdown events
@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup logic (if any)
    logger.info("Application is starting up")
    yield
    # Shutdown logic
    logger.info("Application has been shut down")

# Parse CORS origins from environment variable
def get_allowed_origins():
    origins_str = APP_CONFIG.get("APP_ALLOWED_ORIGINS", "http://localhost:8080")
    # Split by comma and strip whitespace
    origins = [origin.strip() for origin in origins_str.split(",")]
    logger.info(f"CORS allowed origins: {origins}")
    return origins

# START APP
app = FastAPI(
    title="PowerOn | Data Platform API", 
    description=f"Backend API for the Multi-Agent Platform by ValueOn AG ({instanceLabel})",
    lifespan=lifespan
)

# CORS configuration using environment variables
app.add_middleware(
    CORSMiddleware,
    allow_origins= get_allowed_origins(),
    allow_credentials=True,
    allow_methods=["GET", "POST", "PUT", "DELETE", "OPTIONS"],
    allow_headers=["*"],
    expose_headers=["*"],
    max_age=86400  # Increased caching for preflight requests
)

# Static folder for frontend - work with absolute path
baseDir = pathlib.Path(__file__).parent
staticFolder = baseDir / "static"
os.makedirs(staticFolder, exist_ok=True)

# Mount static files with proper configuration
app.mount("/static", StaticFiles(directory=str(staticFolder), html=True), name="static")

# Include all routers
from routes.routeGeneral import router as generalRouter
app.include_router(generalRouter)

from routes.routeAttributes import router as attributesRouter
app.include_router(attributesRouter)

from routes.routeMandates import router as mandateRouter
app.include_router(mandateRouter)

from routes.routeUsers import router as userRouter
app.include_router(userRouter)

from routes.routeFiles import router as fileRouter
app.include_router(fileRouter)

from routes.routePrompts import router as promptRouter
app.include_router(promptRouter)

from routes.routeWorkflows import router as workflowRouter
app.include_router(workflowRouter)

from routes.routeMsft import router as msftRouter
app.include_router(msftRouter)