import React, { useState, useEffect } from 'react';
import axios from 'axios';
import Login from './components/Auth/Login';
import Register from './components/Auth/Register';
import LevelList from './components/Levels/LevelList';
import LevelEditor from './components/Levels/LevelEditor';
import GamePlayer from './components/Game/GamePlayer';
import { authAPI } from './api';
import { Level } from './types';
import './App.css';

type AppState = 'login' | 'register' | 'levels' | 'playing' | 'editing';

const App: React.FC = () => {
    const [appState, setAppState] = useState<AppState>('login');
    const [currentLevelId, setCurrentLevelId] = useState<number | null>(null);
    const [loading, setLoading] = useState(true);
    const [authStatusMessage, setAuthStatusMessage] = useState<string | null>(null);

    useEffect(() => {
        // Check if user is already logged in via cookie
        validateAuth();
    }, []);

    const validateAuth = async () => {
        try {
            await authAPI.whoami();
            setAppState('levels');
            setAuthStatusMessage(null);
        } catch (error: unknown) {
            const message = axios.isAxiosError(error) && error.response?.status === 400
                ? (typeof error.response.data === 'string' ? error.response.data : error.response.data?.message || 'Bad Request')
                : null;
            setAuthStatusMessage(message ? `Auth check failed: ${message}` : null);
            setAppState('login');
        } finally {
            setLoading(false);
        }
    };

    const handleAuthSuccess = () => {
        setAppState('levels');
        setAuthStatusMessage(null);
    };

    const handleLogout = async () => {
        try {
            await authAPI.logout();
        } catch (error) {
            console.error('Logout failed:', error);
        } finally {
            setAppState('login');
            setCurrentLevelId(null);
            setAuthStatusMessage(null);
        }
    };

    const handlePlayLevel = (levelId: number) => {
        setCurrentLevelId(levelId);
        setAppState('playing');
    };

    const handleCreateLevel = () => {
        setAppState('editing');
    };

    const handleCancelEditor = () => {
        setAppState('levels');
    };

    const handleLevelSaved = (level: Level) => {
        console.log('Level saved:', level);
        setAppState('levels');
    };

    const handleBackToLevels = () => {
        setCurrentLevelId(null);
        setAppState('levels');
    };

    if (loading) {
        return (
            <div className="app-loading">
                <div className="loading-spinner"></div>
                <p>Loading Block Game...</p>
            </div>
        );
    }

    switch (appState) {
        case 'login':
            return (
                <Login
                    onLogin={handleAuthSuccess}
                    authStatusMessage={authStatusMessage ?? undefined}
                    onSwitchToRegister={() => {
                        setAuthStatusMessage(null);
                        setAppState('register');
                    }}
                />
            );

        case 'register':
            return (
                <Register
                    onRegister={handleAuthSuccess}
                    onSwitchToLogin={() => setAppState('login')}
                />
            );

        case 'levels':
            return (
                <LevelList
                    onPlayLevel={handlePlayLevel}
                    onCreateLevel={handleCreateLevel}
                    onLogout={handleLogout}
                />
            );

        case 'editing':
            return (
                <LevelEditor
                    onCancel={handleCancelEditor}
                    onSaved={handleLevelSaved}
                />
            );

        case 'playing':
            if (!currentLevelId) {
                setAppState('levels');
                return null;
            }
            return (
                <GamePlayer
                    levelId={currentLevelId}
                    onBack={handleBackToLevels}
                />
            );

        default:
            return (
                <div className="app-error">
                    <h1>Something went wrong</h1>
                    <button onClick={() => setAppState('login')}>
                        Go to Login
                    </button>
                </div>
            );
    }
};

export default App;