from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi.exceptions import RequestValidationError
from starlette.exceptions import HTTPException as StarletteHTTPException

from app.config.settings import settings
from app.database.connection import init_db
from app.middleware.error_handler import (
    http_exception_handler,
    validation_exception_handler,
    general_exception_handler
)
from app.routes import auth, chat, sessions, documents, news, admin_policies, reports
from app.routes import settings as settings_router

# Create FastAPI app
app = FastAPI(
    title="Builder's AI API",
    description="Construction AI Assistant API with Multi-Agent RAG System",
    version="1.0.0"
)

# CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=settings.cors_origins,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Exception handlers
app.add_exception_handler(StarletteHTTPException, http_exception_handler)
app.add_exception_handler(RequestValidationError, validation_exception_handler)
app.add_exception_handler(Exception, general_exception_handler)

# Include routers
app.include_router(auth.router)
app.include_router(chat.router)
app.include_router(sessions.router)
app.include_router(documents.router)
app.include_router(news.router)
app.include_router(admin_policies.router)
app.include_router(reports.router)
app.include_router(settings_router.router)


@app.on_event("startup")
async def startup_event():
    """Initialize database on startup."""
    print("Initializing database...")
    init_db()
    print("Database initialized successfully!")


@app.on_event("shutdown")
async def shutdown_event():
    """Cleanup on shutdown."""
    print("Shutting down...")


@app.get("/")
async def root():
    """Root endpoint."""
    return {
        "message": "Welcome to Builder's AI API",
        "version": "1.0.0",
        "docs": "/docs"
    }


@app.get("/health")
async def health_check():
    """Health check endpoint."""
    return {"status": "healthy"}


if __name__ == "__main__":
    import uvicorn
    from app.config.settings import settings as app_settings
    uvicorn.run(app, host="0.0.0.0", port=app_settings.PORT)