import React, { useEffect, useState } from 'react';
import { StyleSheet, ActivityIndicator, TouchableOpacity } from 'react-native';
import { ThemedText, ThemedView } from '@/components/theme/Theme';
import { Countdown, Relationship, User } from '@/constants/Types';
import { getCountdown } from '@/constants/APIs';
import TextButton from '@/components/theme/buttons/TextButton';
import {
  getCountdown as getCountdownFromSecureStore,
  getUser,
  getRelationship,
  saveCountdown,
} from '@/components/services/SecureStore';
import CountdownChangeDateModal from '@/components/home/CountdownChangeDateModal';

const CountdownView = () => {
  const [countdownData, setCountdownData] = useState({
    days: 0,
    hours: 0,
    minutes: 0,
    seconds: 0,
  });
  const [countdown, setCountdown] = useState<Countdown | null>(null);
  const [isLoading, setIsLoading] = useState(true);
  const [isDateModalOpen, setIsDateModalOpen] = useState(false);
  const [user, setUser] = useState<User | null>(null);
  const [relationship, setRelationship] = useState<Relationship | null>(null);

  useEffect(() => {
    const loadData = async () => {
      setIsLoading(true);
      const userData = await getUser();
      setUser(userData);
      const relationshipData = await getRelationship();
      setRelationship(relationshipData);
      const countdownFromSecureStore = await getCountdownFromSecureStore();
      if (countdownFromSecureStore) {
        setCountdown(countdownFromSecureStore);
      } else if (userData) {
        const countdownFromServer = await getCountdown(userData.id);
        if (countdownFromServer) {
          setCountdown(countdownFromServer);
          await saveCountdown(countdownFromServer);
        }
      }
      setIsLoading(false);
    };
    loadData();
  }, []);

  useEffect(() => {
    if (countdown === null) return;
    const interval = setInterval(() => {
      const now = new Date();
      const diff = new Date(countdown.date).getTime() - now.getTime();
      const days = Math.floor(diff / (1000 * 60 * 60 * 24));
      const hours = Math.floor((diff % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
      const minutes = Math.floor((diff % (1000 * 60 * 60)) / (1000 * 60));
      const seconds = Math.floor((diff % (1000 * 60)) / 1000);
      setCountdownData({ days, hours, minutes, seconds });
      if (diff <= 0) {
        clearInterval(interval);
        setCountdownData({ days: 0, hours: 0, minutes: 0, seconds: 0 });
      }
    }, 1000);
    return () => clearInterval(interval);
  }, [countdown]);

  const handleCountdownUpdate = async (newDate: Date, newTitle: string) => {
    if (relationship) {
      const newCountdown: Countdown = countdown
        ? { ...countdown, date: newDate, title: newTitle }
        : {
            id: 0, // This will be set by the server
            relationshipId: relationship.id,
            title: newTitle ? newTitle : 'Countdown to Next Visit',
            date: newDate,
            createdAt: new Date(),
          };
      setCountdown(newCountdown);
      await saveCountdown(newCountdown);
    }
  };

  if (isLoading) {
    return (
      <ThemedView style={styles.container}>
        <ActivityIndicator size='large' color='#0000ff' />
      </ThemedView>
    );
  }
  if (!relationship) {
    return (
      <ThemedView style={styles.container}>
        <ThemedText>You are not in a relationship yet.</ThemedText>
      </ThemedView>
    );
  }

  if (!countdown) {
    return (
      <ThemedView style={styles.container}>
        <ThemedText>No countdown set yet.</ThemedText>
        <TextButton
          width={320} height={68}
          text='Set Countdown'
          fontSize={24}
          onPress={() => setIsDateModalOpen(true)}
        />
      </ThemedView>
    );
  }

  return (
    <ThemedView style={styles.innerContainer}>
      <ThemedText style={styles.title}>
        {countdown?.title ?? 'Countdown til Next Visit'}
      </ThemedText>
      <ThemedView style={styles.countdownContainer}>
        <CountdownItem
          value={countdownData.days}
          label={countdownData.days === 1 ? 'Day' : 'Days'}
        />
        <CountdownItem
          value={countdownData.hours}
          label={countdownData.hours === 1 ? 'Hour' : 'Hours'}
        />
        <CountdownItem
          value={countdownData.minutes}
          label={countdownData.minutes === 1 ? 'Minute' : 'Minutes'}
        />
        <CountdownItem
          value={countdownData.seconds}
          label={countdownData.seconds === 1 ? 'Second' : 'Seconds'}
        />
      </ThemedView>
      <TextButton
        width={160} height={48}
        text='Change Countdown'
        fontSize={18}
        onPress={() => setIsDateModalOpen(true)}
      />
      {user && countdown && (
        <CountdownChangeDateModal
          user={user}
          isVisible={isDateModalOpen}
          onClose={() => setIsDateModalOpen(false)}
          onDateChange={handleCountdownUpdate}
          currentCountdown={countdown}
        />
      )}
    </ThemedView>
  );

};
export default CountdownView;

const CountdownItem = ({value, label}: { value: number, label: string }) => {
  return (
    <ThemedView style={styles.countdownItem}>
      <ThemedText style={styles.countdownValue}>{value}</ThemedText>
      <ThemedText style={styles.countdownLabel}>{label}</ThemedText>
    </ThemedView>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: 'transparent',
  },
  innerContainer: {
    flex: 1,
    alignItems: 'center',
    paddingHorizontal: 10,
    backgroundColor: 'transparent',
  },
  title: {
    fontSize: 24,
    lineHeight: 32,
    fontWeight: '600',
    textAlign: 'center',
    marginHorizontal: 'auto',
  },
  countdownContainer: {
    flexDirection: 'row',
    justifyContent: 'space-around',
    alignItems: 'center',
    width: '90%',
    backgroundColor: 'transparent',
    marginVertical: 10,
  },
  countdownItem: {
    alignItems: 'center',
    marginHorizontal: 5,
    backgroundColor: 'transparent',
  },
  countdownValue: {
    fontSize: 28,
    lineHeight: 42,
    fontWeight: 'bold',
  },
  countdownLabel: {
    fontSize: 18,
    lineHeight: 24,
  },
});