import { useEffect, useRef } from 'react';
import { Badge, List, Popover, Button, Empty, Typography } from 'antd';
import { BellOutlined } from '@ant-design/icons';
import { useNavigate } from 'react-router-dom';
import { useMessageStore } from '../stores/message';
import { useThemeMode } from '../hooks/useThemeMode';

const { Text } = Typography;

export default function NotificationPanel() {
  const navigate = useNavigate();
  const unreadCount = useMessageStore((s) => s.unreadCount);
  const recentMessages = useMessageStore((s) => s.recentMessages);
  const markAsRead = useMessageStore((s) => s.markAsRead);
  const isDark = useThemeMode();
  const initializedRef = useRef(false);

  useEffect(() => {
    if (initializedRef.current) return;
    initializedRef.current = true;

    const { fetchUnreadCount, fetchRecentMessages, connectSSE } = useMessageStore.getState();
    fetchUnreadCount();
    fetchRecentMessages();

    const disconnectSSE = connectSSE();

    const interval = setInterval(() => {
      fetchUnreadCount();
      fetchRecentMessages();
    }, 60000);

    return () => {
      clearInterval(interval);
      disconnectSSE();
      initializedRef.current = false;
    };
  }, []);

  const content = (
    <div style={{ width: 360 }}>
      <div style={{
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'space-between',
        marginBottom: 12,
        padding: '4px 0',
      }}>
        <span style={{ fontWeight: 600, fontSize: 14 }}>通知</span>
        {unreadCount > 0 && (
          <Button
            type="text"
            size="small"
            style={{ fontSize: 12, color: '#2563eb' }}
            onClick={() => navigate('/messages')}
          >
            查看全部
          </Button>
        )}
      </div>

      {recentMessages.length === 0 ? (
        <Empty
          description="暂无消息"
          image={Empty.PRESENTED_IMAGE_SIMPLE}
          style={{ padding: '24px 0' }}
        />
      ) : (
        <List
          dataSource={recentMessages.slice(0, 5)}
          renderItem={(item) => (
            <List.Item
              style={{
                padding: '10px 12px',
                margin: '2px 0',
                borderRadius: 8,
                cursor: 'pointer',
                transition: 'background 0.15s ease',
                border: 'none',
                background: !item.is_read ? (isDark ? '#0f172a' : '#eff6ff') : 'transparent',
              }}
              onClick={() => {
                if (!item.is_read) {
                  markAsRead(item.id);
                }
                navigate('/messages');
              }}
              onMouseEnter={(e) => {
                if (item.is_read) {
                  e.currentTarget.style.background = isDark ? '#0f172a' : '#f1f5f9';
                }
              }}
              onMouseLeave={(e) => {
                if (item.is_read) {
                  e.currentTarget.style.background = 'transparent';
                }
              }}
            >
              <div style={{ flex: 1, minWidth: 0 }}>
                <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
                  <Text
                    strong={!item.is_read}
                    ellipsis
                    style={{ maxWidth: 260, fontSize: 13 }}
                  >
                    {item.title}
                  </Text>
                  {!item.is_read && (
                    <span style={{
                      display: 'inline-block',
                      width: 6,
                      height: 6,
                      borderRadius: '50%',
                      background: '#2563eb',
                      flexShrink: 0,
                    }} />
                  )}
                </div>
                <Text
                  type="secondary"
                  ellipsis
                  style={{ maxWidth: 300, fontSize: 12, display: 'block', marginTop: 2 }}
                >
                  {item.body}
                </Text>
              </div>
            </List.Item>
          )}
        />
      )}

      {recentMessages.length > 0 && (
        <div style={{
          textAlign: 'center',
          paddingTop: 8,
          marginTop: 4,
          borderTop: `1px solid ${isDark ? '#0f172a' : '#f8fafc'}`,
        }}>
          <Button
            type="text"
            onClick={() => navigate('/messages')}
            style={{ fontSize: 13, color: '#2563eb', fontWeight: 500 }}
          >
            查看全部消息
          </Button>
        </div>
      )}

    </div>
  );

  return (
    <Popover
      content={content}
      trigger="click"
      placement="bottomRight"
      overlayStyle={{ padding: 0 }}
    >
      <div
        style={{
          width: 36,
          height: 36,
          borderRadius: 8,
          display: 'flex',
          alignItems: 'center',
          justifyContent: 'center',
          cursor: 'pointer',
          transition: 'all 0.15s ease',
          position: 'relative',
        }}
        onMouseEnter={(e) => {
          e.currentTarget.style.background = isDark ? '#0f172a' : '#f8fafc';
        }}
        onMouseLeave={(e) => {
          e.currentTarget.style.background = 'transparent';
        }}
      >
        <Badge count={unreadCount} size="small" offset={[4, -4]}>
          <BellOutlined style={{
            fontSize: 16,
            color: isDark ? '#94a3b8' : '#475569',
          }} />
        </Badge>
      </div>
    </Popover>
  );
}
