import React, { useEffect, useState, Component } from 'react';
import { View, StatusBar, Text, ScrollView } from 'react-native';
import { NavigationContainer, DarkTheme } from '@react-navigation/native';
import { createBottomTabNavigator } from '@react-navigation/bottom-tabs';
import { createStackNavigator } from '@react-navigation/stack';
import { SafeAreaProvider } from 'react-native-safe-area-context';
import { GestureHandlerRootView } from 'react-native-gesture-handler';
import { Ionicons } from '@expo/vector-icons';
import TrackPlayer, { Event, State } from 'react-native-track-player';
import { setupPlayer } from './src/audio/player';
import { useStore } from './src/store';

import HomeScreen         from './src/screens/Home';
import { ArtistsScreen, AlbumsScreen } from './src/screens/Library';
import ArtistDetailScreen from './src/screens/ArtistDetail';
import AlbumDetailScreen  from './src/screens/AlbumDetail';
import SearchScreen       from './src/screens/Search';
import LoginScreen        from './src/screens/Login';
import NowPlayingScreen   from './src/screens/NowPlaying';
import PlayerBar          from './src/components/PlayerBar';

// ─── ERROR BOUNDARY ───
class ErrorBoundary extends Component {
  state = { error: null };
  static getDerivedStateFromError(e) { return { error: e }; }
  render() {
    if (this.state.error) {
      return (
        <ScrollView style={{ flex: 1, backgroundColor: '#121212', padding: 24, paddingTop: 60 }}>
          <Text style={{ color: '#e05252', fontSize: 16, fontWeight: '700', marginBottom: 12 }}>
            Fehler beim Starten
          </Text>
          <Text style={{ color: '#fff', fontSize: 13, fontFamily: 'monospace' }}>
            {this.state.error?.message || String(this.state.error)}
          </Text>
          <Text style={{ color: '#aaa', fontSize: 12, marginTop: 16 }}>
            {this.state.error?.stack}
          </Text>
        </ScrollView>
      );
    }
    return this.props.children;
  }
}

const Tab   = createBottomTabNavigator();
const Stack = createStackNavigator();

function HomeTabs() {
  return (
    <Tab.Navigator
      screenOptions={({ route }) => ({
        headerShown: false,
        tabBarStyle: { backgroundColor: '#1e1e1e', borderTopColor: '#2a2a2a' },
        tabBarActiveTintColor: '#1db954',
        tabBarInactiveTintColor: '#888',
        tabBarIcon: ({ color, size }) => {
          const icons = { Home: 'home', Artists: 'person', Albums: 'disc', Search: 'search', Settings: 'settings-outline' };
          return <Ionicons name={icons[route.name] || 'ellipse'} size={size} color={color} />;
        },
      })}
    >
      <Tab.Screen name="Home"     component={HomeScreen}    options={{ title: 'Start' }} />
      <Tab.Screen name="Artists"  component={ArtistsScreen} options={{ title: 'Künstler' }} />
      <Tab.Screen name="Albums"   component={AlbumsScreen}  options={{ title: 'Alben' }} />
      <Tab.Screen name="Search"   component={SearchScreen}  options={{ title: 'Suche' }} />
      <Tab.Screen name="Settings" component={LoginScreen}   options={{ title: 'Einstellungen' }} />
    </Tab.Navigator>
  );
}

function RootNavigator() {
  const currentTrack = useStore(s => s.currentTrack);
  return (
    <View style={{ flex: 1 }}>
      <Stack.Navigator screenOptions={{ headerShown: false }}>
        <Stack.Screen name="Tabs"         component={HomeTabs} />
        <Stack.Screen name="NowPlaying"   component={NowPlayingScreen} options={{ presentation: 'modal' }} />
        <Stack.Screen name="AlbumDetail"  component={AlbumDetailScreen} />
        <Stack.Screen name="ArtistDetail" component={ArtistDetailScreen} />
      </Stack.Navigator>
      {currentTrack && <PlayerBar />}
    </View>
  );
}

export default function App() {
  const { loadConfig } = useStore();
  const [ready, setReady] = useState(false);
  const [initError, setInitError] = useState(null);

  useEffect(() => {
    (async () => {
      try {
        await loadConfig();
        await setupPlayer();
      } catch (e) {
        setInitError(e?.message || String(e));
      }
      setReady(true);
    })();
  }, []);

  useEffect(() => {
    const sub1 = TrackPlayer.addEventListener(Event.PlaybackActiveTrackChanged, e => {
      if (e.track) useStore.getState().setCurrentTrack(e.track._song || e.track);
    });
    const sub2 = TrackPlayer.addEventListener(Event.PlaybackState, e => {
      useStore.getState().setIsPlaying(e.state === State.Playing);
    });
    return () => { sub1.remove(); sub2.remove(); };
  }, []);

  if (!ready) return (
    <View style={{ flex: 1, backgroundColor: '#121212' }} />
  );

  if (initError) return (
    <ScrollView style={{ flex: 1, backgroundColor: '#121212', padding: 24, paddingTop: 60 }}>
      <Text style={{ color: '#e05252', fontSize: 16, fontWeight: '700', marginBottom: 12 }}>Init-Fehler</Text>
      <Text style={{ color: '#fff', fontSize: 13 }}>{initError}</Text>
    </ScrollView>
  );

  return (
    <ErrorBoundary>
      <GestureHandlerRootView style={{ flex: 1 }}>
        <SafeAreaProvider>
          <StatusBar barStyle="light-content" backgroundColor="#121212" />
          <NavigationContainer theme={{
            ...DarkTheme,
            colors: {
              ...DarkTheme.colors,
              primary:      '#1db954',
              background:   '#121212',
              card:         '#1e1e1e',
              text:         '#ffffff',
              border:       '#2a2a2a',
              notification: '#1db954',
            },
          }}>
            <RootNavigator />
          </NavigationContainer>
        </SafeAreaProvider>
      </GestureHandlerRootView>
    </ErrorBoundary>
  );
}