import React, { useState, useEffect, useCallback } from 'react';
import {
  Box,
  VStack,
  HStack,
  Text,
  Badge,
  Button,
  Icon,
  Center,
  Spinner,
  LinkBox,
  LinkOverlay,
  Tooltip,
  Tag,
  TagLabel,
  Wrap,
  WrapItem,
  useColorModeValue,
  useToast,
} from '@chakra-ui/react';
import { Link } from 'react-router-dom';
import {
  FiCalendar,
  FiClock,
  FiStar,
  FiTrendingUp,
  FiAlertCircle,
} from 'react-icons/fi';
import { eventService } from '../../../services/eventService';
import moment from 'moment';

export default function MyFutureEvents({ limit = 5 }) {
  const [futureEvents, setFutureEvents] = useState([]);
  const [loading, setLoading] = useState(true);
  const toast = useToast();

  // 颜色主题
  const borderColor = useColorModeValue('gray.200', 'gray.600');
  const hoverBg = useColorModeValue('gray.50', 'gray.700');
  const secondaryText = useColorModeValue('gray.600', 'gray.400');
  const importanceBg = useColorModeValue('yellow.50', 'yellow.900');
  const importanceColor = useColorModeValue('yellow.600', 'yellow.300');

  // 加载关注的未来事件
  const loadFutureEvents = useCallback(async () => {
    try {
      setLoading(true);
      const response = await eventService.calendar.getFollowingEvents();
      if (response.success) {
        // 按时间排序，最近的在前
        const sortedEvents = (response.data || []).sort((a, b) => 
          moment(a.calendar_time).valueOf() - moment(b.calendar_time).valueOf()
        );
        setFutureEvents(sortedEvents);
      }
    } catch (error) {
      console.error('加载未来事件失败:', error);
      toast({
        title: '加载失败',
        description: '无法加载关注的未来事件',
        status: 'error',
        duration: 3000,
        isClosable: true,
      });
    } finally {
      setLoading(false);
    }
  }, [toast]);

  useEffect(() => {
    loadFutureEvents();
  }, [loadFutureEvents]);

  // 取消关注
  const handleUnfollow = async (eventId) => {
    try {
      const response = await eventService.calendar.toggleFollow(eventId);
      if (response.success) {
        setFutureEvents(prev => prev.filter(event => event.id !== eventId));
        toast({
          title: '取消关注成功',
          status: 'success',
          duration: 2000,
          isClosable: true,
        });
      }
    } catch (error) {
      console.error('取消关注失败:', error);
      toast({
        title: '操作失败',
        description: '取消关注失败，请重试',
        status: 'error',
        duration: 3000,
        isClosable: true,
      });
    }
  };

  // 格式化时间
  const formatEventTime = (time) => {
    const eventTime = moment(time);
    const now = moment();
    const daysDiff = eventTime.diff(now, 'days');
    
    if (daysDiff === 0) {
      return {
        date: '今天',
        time: eventTime.format('HH:mm'),
        color: 'red',
        urgent: true
      };
    } else if (daysDiff === 1) {
      return {
        date: '明天',
        time: eventTime.format('HH:mm'),
        color: 'orange',
        urgent: true
      };
    } else if (daysDiff <= 7) {
      return {
        date: `${daysDiff}天后`,
        time: eventTime.format('MM/DD HH:mm'),
        color: 'yellow',
        urgent: false
      };
    } else {
      return {
        date: eventTime.format('MM月DD日'),
        time: eventTime.format('HH:mm'),
        color: 'gray',
        urgent: false
      };
    }
  };

  // 获取重要性颜色
  const getImportanceColor = (star) => {
    if (star >= 5) return 'red';
    if (star >= 4) return 'orange';
    if (star >= 3) return 'yellow';
    return 'blue';
  };

  if (loading) {
    return (
      <Center py={4}>
        <Spinner size="sm" />
      </Center>
    );
  }

  if (futureEvents.length === 0) {
    return (
      <Center py={8}>
        <VStack spacing={3}>
          <Icon as={FiCalendar} boxSize={12} color="gray.300" />
          <Text color={secondaryText} fontSize="sm">
            暂无关注的未来事件
          </Text>
          <Button
            size="sm"
            variant="outline"
            colorScheme="blue"
            as={Link}
            to="/community"
          >
            探索投资日历
          </Button>
        </VStack>
      </Center>
    );
  }

  return (
    <VStack align="stretch" spacing={3}>
      {futureEvents.slice(0, limit).map((event) => {
        const timeInfo = formatEventTime(event.calendar_time);
        
        return (
          <LinkBox
            key={event.id}
            p={4}
            borderRadius="lg"
            border="1px"
            borderColor={borderColor}
            bg={timeInfo.urgent ? importanceBg : 'transparent'}
            _hover={{ shadow: 'md', transform: 'translateY(-2px)' }}
            transition="all 0.2s"
            position="relative"
          >
            {/* 紧急标记 */}
            {timeInfo.urgent && (
              <Box
                position="absolute"
                top={2}
                right={2}
              >
                <Badge colorScheme={timeInfo.color} variant="solid" fontSize="xs">
                  即将发生
                </Badge>
              </Box>
            )}

            <VStack align="stretch" spacing={3}>
              {/* 标题 */}
              <LinkOverlay as={Link} to="/community">
                <Text fontWeight="medium" fontSize="md" noOfLines={2}>
                  {event.title}
                </Text>
              </LinkOverlay>

              {/* 时间和重要性 */}
              <HStack justify="space-between">
                <HStack spacing={3}>
                  <Badge colorScheme={timeInfo.color} variant="subtle">
                    <HStack spacing={1}>
                      <Icon as={FiClock} boxSize={3} />
                      <Text>{timeInfo.date}</Text>
                    </HStack>
                  </Badge>
                  <Text fontSize="sm" color={secondaryText}>
                    {timeInfo.time}
                  </Text>
                </HStack>
                
                {/* 重要性星级 */}
                <HStack spacing={0}>
                  {[...Array(5)].map((_, i) => (
                    <Icon
                      key={i}
                      as={FiStar}
                      boxSize={3}
                      color={i < event.star ? importanceColor : 'gray.300'}
                      fill={i < event.star ? 'currentColor' : 'none'}
                    />
                  ))}
                </HStack>
              </HStack>

              {/* 标签和相关信息 */}
              <HStack justify="space-between" flexWrap="wrap">
                <HStack spacing={2}>
                  {event.type && (
                    <Tag size="sm" variant="subtle" colorScheme={event.type === 'event' ? 'blue' : 'green'}>
                      <TagLabel>{event.type === 'event' ? '事件' : '数据'}</TagLabel>
                    </Tag>
                  )}
                  {event.related_stocks && event.related_stocks.length > 0 && (
                    <Tag size="sm" variant="subtle" colorScheme="purple">
                      <Icon as={FiTrendingUp} boxSize={3} mr={1} />
                      <TagLabel>{event.related_stocks.length}只相关股票</TagLabel>
                    </Tag>
                  )}
                </HStack>

                {/* 操作按钮 */}
                <Button
                  size="xs"
                  variant="ghost"
                  colorScheme="red"
                  onClick={(e) => {
                    e.preventDefault();
                    handleUnfollow(event.id);
                  }}
                >
                  取消关注
                </Button>
              </HStack>

              {/* 预测信息 */}
              {event.forecast && (
                <Box>
                  <HStack spacing={1} mb={1}>
                    <Icon as={FiAlertCircle} boxSize={3} color={secondaryText} />
                    <Text fontSize="xs" color={secondaryText}>
                      预测
                    </Text>
                  </HStack>
                  <Text fontSize="sm" color={secondaryText} noOfLines={2}>
                    {event.forecast}
                  </Text>
                </Box>
              )}
            </VStack>
          </LinkBox>
        );
      })}

      {/* 查看更多 */}
      {futureEvents.length > limit && (
        <Button
          size="sm"
          variant="ghost"
          as={Link}
          to="/community"
        >
          查看全部 ({futureEvents.length})
        </Button>
      )}
    </VStack>
  );
}