from fastapi import FastAPI
from contextlib import asynccontextmanager
import logging

from database import DatabaseManager, PostgresSessionLocal
from models import DataSource
from scheduler import scheduler_manager
from api import router

# Логирование
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)


@asynccontextmanager
async def lifespan(app: FastAPI):
    """Управление жизненным циклом приложения"""
    # Startup
    logger.info("Starting Data Replication Service...")
    
    # Инициализировать БД
    DatabaseManager.init_postgres_db()
    logger.info("PostgreSQL database initialized")
    
    # Проверить подключение к целевой БД
    postgres_ok = DatabaseManager.test_postgres_connection()
    
    if not postgres_ok:
        logger.warning("Target PostgreSQL connection failed! Replication service requires target database.")
    else:
        logger.info("Target PostgreSQL connection successful")
    
    # Проверить доступные источники данных
    session = PostgresSessionLocal()
    try:
        data_sources = session.query(DataSource).filter(DataSource.is_active == True).all()
        if not data_sources:
            logger.warning("No active data sources configured. Add data sources via API before replication.")
        else:
            logger.info(f"Found {len(data_sources)} active data source(s):")
            for source in data_sources:
                is_ok = DatabaseManager.test_source_connection(source.id)
                status = "✓" if is_ok else "✗"
                logger.info(f"  {status} {source.name} ({source.source_type.value})")
    finally:
        session.close()
    
    # Запустить планировщик
    scheduler_manager.start()
    logger.info("Scheduler started")
    
    yield
    
    # Shutdown
    logger.info("Shutting down Data Replication Service...")
    scheduler_manager.stop()
    logger.info("Scheduler stopped")


app = FastAPI(
    title="Data Replication Service",
    description="Service for replicating data from multiple sources (MSSQL, PostgreSQL) to target PostgreSQL database using DLT. Configure data sources dynamically without restart.",
    version="1.0.0",
    lifespan=lifespan
)

# Подключить маршруты API
app.include_router(router)


@app.get("/")
def read_root():
    """Root endpoint"""
    return {
        "message": "Data Replication Service is running",
        "docs": "/docs",
        "openapi": "/openapi.json",
        "features": [
            "Dynamic data source management",
            "Multiple source types (MSSQL, PostgreSQL)",
            "Cron-based scheduling",
            "DLT-powered data transfer",
            "Real-time monitoring"
        ]
    }


if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)