import { useAuth } from '@/assets/contexts/useAuth';
import { getCachedContacts } from '@/assets/services/offlineStorage';
import { colors } from '@/assets/styles/colors';
import { fonts } from '@/assets/styles/fonts';
import { FontAwesome } from '@expo/vector-icons';
import { useEffect, useState } from 'react';
import { Alert, Linking, Platform, StyleSheet, Text, useWindowDimensions } from 'react-native';
import { Gesture, GestureDetector } from 'react-native-gesture-handler';
import Animated, {
    runOnJS,
    useAnimatedStyle,
    useSharedValue,
    withSpring,
    withTiming,
} from 'react-native-reanimated';
import { useSafeAreaInsets } from 'react-native-safe-area-context';

const BTN_SIZE = 64;
const MARGIN = 16;

export function EmergencyButton() {
  const { isAuthenticated } = useAuth();
  const insets = useSafeAreaInsets();
  const { width: screenWidth, height: screenHeight } = useWindowDimensions();
  const [emergencyPhone, setEmergencyPhone] = useState<string | null>(null);

  const tabBarHeight = (Platform.OS === 'ios' ? 54 : 64) + insets.bottom;
  const maxX = screenWidth - BTN_SIZE - MARGIN;
  const minY = insets.top + MARGIN;
  const maxY = screenHeight - tabBarHeight - BTN_SIZE - MARGIN;

  const x = useSharedValue(screenWidth - BTN_SIZE - MARGIN);
  const y = useSharedValue(screenHeight - tabBarHeight - BTN_SIZE - MARGIN);
  const startX = useSharedValue(0);
  const startY = useSharedValue(0);
  const scale = useSharedValue(1);
  const isDragActive = useSharedValue(false);

  useEffect(() => {
    if (!isAuthenticated) return;
    getCachedContacts().then(({ contactData }) => {
      if (contactData?.emergencyPhone) {
        setEmergencyPhone(contactData.emergencyPhone);
      }
    });
  }, [isAuthenticated]);

  const handlePress = () => {
    if (!emergencyPhone) return;
    const url = `tel:${emergencyPhone.replace(/\s/g, '')}`;
    Alert.alert(
      'Linha de Emergência 24h',
      `Ligar para ${emergencyPhone}?`,
      [
        { text: 'Cancelar', style: 'cancel' },
        {
          text: 'Ligar',
          style: 'default',
          onPress: () =>
            Linking.openURL(url).catch(() =>
              Alert.alert('Erro', 'Não foi possível abrir a aplicação de chamadas.'),
            ),
        },
      ],
    );
  };

  // Toque simples → abre o Alert
  const tap = Gesture.Tap()
    .maxDuration(500)
    .onEnd(() => {
      runOnJS(handlePress)();
    });

  // Segurar 800ms → ativa modo arrasto com feedback de escala
  const longPress = Gesture.LongPress()
    .minDuration(800)
    .onStart(() => {
      isDragActive.value = true;
      scale.value = withSpring(1.2, { damping: 12, stiffness: 200 });
      startX.value = x.value;
      startY.value = y.value;
    });

  // Pan → só move quando o modo arrasto está ativo
  const pan = Gesture.Pan()
    .onUpdate((e) => {
      if (!isDragActive.value) return;
      x.value = Math.max(MARGIN, Math.min(maxX, startX.value + e.translationX));
      y.value = Math.max(minY, Math.min(maxY, startY.value + e.translationY));
    })
    .onEnd(() => {
      if (!isDragActive.value) return;
      isDragActive.value = false;
      scale.value = withSpring(1, { damping: 15, stiffness: 250 });
      // snap para a borda mais próxima sem bounce
      const snapRight = x.value + BTN_SIZE / 2 > screenWidth / 2;
      x.value = withTiming(snapRight ? maxX : MARGIN, { duration: 250 });
    });

  const composed = Gesture.Race(
    tap,
    Gesture.Simultaneous(longPress, pan),
  );

  const animatedStyle = useAnimatedStyle(() => ({
    transform: [
      { translateX: x.value },
      { translateY: y.value },
      { scale: scale.value },
    ],
  }));

  if (!isAuthenticated || !emergencyPhone) return null;

  return (
    <GestureDetector gesture={composed}>
      <Animated.View style={[styles.btn, animatedStyle]}>
        <FontAwesome name="phone" size={18} color={colors.branco} />
        <Text style={styles.label}>SOS</Text>
      </Animated.View>
    </GestureDetector>
  );
}

const styles = StyleSheet.create({
  btn: {
    position: 'absolute',
    top: 0,
    left: 0,
    width: BTN_SIZE,
    height: BTN_SIZE,
    borderRadius: BTN_SIZE / 2,
    backgroundColor: colors.vermelho,
    alignItems: 'center',
    justifyContent: 'center',
    gap: 4,
    shadowColor: '#000',
    shadowOpacity: 0.3,
    shadowRadius: 8,
    shadowOffset: { width: 0, height: 4 },
    elevation: 10,
    zIndex: 999,
  },
  label: {
    color: colors.branco,
    fontFamily: fonts.bold,
    fontSize: 11,
    letterSpacing: 0.5,
  },
});