from fastapi import FastAPI, Depends, HTTPException, WebSocket, WebSocketDisconnect
from fastapi.middleware.cors import CORSMiddleware
from typing import List
import json
from app.core.config import settings
from app.api.api import api_router

app = FastAPI(
    title=settings.project_name,
    openapi_url=f"{settings.api_v1_str}/openapi.json",
    description="Prior Permission Required (PPR) system API for aircraft operations management",
    version="2.0.0"
)

# Set up CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Configure this properly for production
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# WebSocket connection manager for real-time updates
class ConnectionManager:
    def __init__(self):
        self.active_connections: List[WebSocket] = []

    async def connect(self, websocket: WebSocket):
        await websocket.accept()
        self.active_connections.append(websocket)

    def disconnect(self, websocket: WebSocket):
        self.active_connections.remove(websocket)

    async def send_personal_message(self, message: str, websocket: WebSocket):
        await websocket.send_text(message)

    async def broadcast(self, message: dict):
        message_str = json.dumps(message)
        for connection in self.active_connections:
            try:
                await connection.send_text(message_str)
            except:
                # Connection is dead, remove it
                self.active_connections.remove(connection)

manager = ConnectionManager()

@app.websocket("/ws/tower-updates")
async def websocket_endpoint(websocket: WebSocket):
    await manager.connect(websocket)
    try:
        while True:
            # Keep connection alive
            data = await websocket.receive_text()
            # Echo back for heartbeat
            await websocket.send_text(f"Heartbeat: {data}")
    except WebSocketDisconnect:
        manager.disconnect(websocket)

@app.get("/")
async def root():
    return {
        "message": "Airfield PPR API", 
        "version": "2.0.0",
        "docs": "/docs"
    }

@app.get("/health")
async def health_check():
    return {"status": "healthy", "timestamp": "2024-01-01T00:00:00Z"}

# Include API router
app.include_router(api_router, prefix=settings.api_v1_str)

# Make connection manager available to the app
app.state.connection_manager = manager