import { HashRouter as Router, Routes, Route, useNavigate } from 'react-router-dom'
import { useEffect, useState } from 'react'
import { useAuthStore } from '@/stores/state'
import { navigationService } from '@/services/navigation'
import { getAuthStatus } from '@/api/lightrag'
import { toast } from 'sonner'
import { Toaster } from 'sonner'
import App from './App'
import LoginPage from '@/features/LoginPage'
import ThemeProvider from '@/components/ThemeProvider'

interface ProtectedRouteProps {
  children: React.ReactNode
}

const ProtectedRoute = ({ children }: ProtectedRouteProps) => {
  const { isAuthenticated } = useAuthStore()
  const [isChecking, setIsChecking] = useState(true)
  const navigate = useNavigate()

  // Set navigate function for navigation service
  useEffect(() => {
    navigationService.setNavigate(navigate)
  }, [navigate])

  useEffect(() => {
    let isMounted = true; // Flag to prevent state updates after unmount

    // This effect will run when the component mounts
    // and will check if authentication is required
    const checkAuthStatus = async () => {
      try {
        // Skip check if already authenticated
        if (isAuthenticated) {
          if (isMounted) setIsChecking(false);
          return;
        }

        const status = await getAuthStatus()

        // Only proceed if component is still mounted
        if (!isMounted) return;

        if (!status.auth_configured && status.access_token) {
          // If auth is not configured, use the guest token
          useAuthStore.getState().login(status.access_token, true)
          if (status.message) {
            toast.info(status.message)
          }
        }
      } catch (error) {
        console.error('Failed to check auth status:', error)
      } finally {
        // Only update state if component is still mounted
        if (isMounted) {
          setIsChecking(false)
        }
      }
    }

    // Execute immediately
    checkAuthStatus()

    // Cleanup function to prevent state updates after unmount
    return () => {
      isMounted = false;
    }
  }, [isAuthenticated])

  // Handle navigation when authentication status changes
  useEffect(() => {
    if (!isChecking && !isAuthenticated) {
      const currentPath = window.location.hash.slice(1); // Remove the '#' from hash
      const isLoginPage = currentPath === '/login';

      if (!isLoginPage) {
        // Use navigation service for redirection
        console.log('Not authenticated, redirecting to login');
        navigationService.navigateToLogin();
      }
    }
  }, [isChecking, isAuthenticated]);

  // Show nothing while checking auth status or when not authenticated on login page
  if (isChecking || (!isAuthenticated && window.location.hash.slice(1) === '/login')) {
    return null;
  }

  // Show children only when authenticated
  if (!isAuthenticated) {
    return null;
  }

  return <>{children}</>;
}

const AppContent = () => {
  const [initializing, setInitializing] = useState(true)
  const { isAuthenticated } = useAuthStore()
  const navigate = useNavigate()

  // Set navigate function for navigation service
  useEffect(() => {
    navigationService.setNavigate(navigate)
  }, [navigate])

  // Check token validity and auth configuration on app initialization
  useEffect(() => {
    let isMounted = true; // Flag to prevent state updates after unmount

    const checkAuth = async () => {
      try {
        const token = localStorage.getItem('LIGHTRAG-API-TOKEN')

        // If we have a token, we're already authenticated
        if (token && isAuthenticated) {
          if (isMounted) setInitializing(false);
          return;
        }

        // If no token or not authenticated, check if auth is configured
        const status = await getAuthStatus()

        // Only proceed if component is still mounted
        if (!isMounted) return;

        if (!status.auth_configured && status.access_token) {
          // If auth is not configured, use the guest token
          useAuthStore.getState().login(status.access_token, true)
          if (status.message) {
            toast.info(status.message)
          }
        } else if (!token) {
          // Only logout if we don't have a token
          useAuthStore.getState().logout()
        }
      } catch (error) {
        console.error('Auth initialization error:', error)
        if (isMounted && !isAuthenticated) {
          useAuthStore.getState().logout()
        }
      } finally {
        // Only update state if component is still mounted
        if (isMounted) {
          setInitializing(false)
        }
      }
    }

    // Execute immediately
    checkAuth()

    // Cleanup function to prevent state updates after unmount
    return () => {
      isMounted = false;
    }
  }, [isAuthenticated])

  // Show nothing while initializing
  if (initializing) {
    return null
  }

  return (
    <Routes>
      <Route path="/login" element={<LoginPage />} />
      <Route
        path="/*"
        element={
          <ProtectedRoute>
            <App />
          </ProtectedRoute>
        }
      />
    </Routes>
  )
}

const AppRouter = () => {
  return (
    <ThemeProvider>
      <Router>
        <AppContent />
        <Toaster position="bottom-center" />
      </Router>
    </ThemeProvider>
  )
}

export default AppRouter