// src/components/EventCommentSection/EventCommentSection.js
/**
 * 事件评论区主组件
 * 功能：整合评论列表 + 评论输入框，管理评论数据
 */

import React, { useState, useEffect, useCallback } from 'react';
import {
  Box,
  VStack,
  Heading,
  Badge,
  HStack,
  Divider,
  useColorModeValue,
  useToast,
} from '@chakra-ui/react';
import { useAuth } from '../../contexts/AuthContext';
import { eventService } from '../../services/eventService';
import { logger } from '../../utils/logger';
import CommentList from './CommentList';
import CommentInput from './CommentInput';

/**
 * 事件评论区组件
 * @param {Object} props
 * @param {number} props.eventId - 事件 ID
 */
const EventCommentSection = ({ eventId }) => {
  const { user } = useAuth();
  const toast = useToast();
  const dividerColor = useColorModeValue('gray.200', 'gray.600');
  const headingColor = useColorModeValue('gray.700', 'gray.200');
  const sectionBg = useColorModeValue('gray.50', 'gray.750');

  // 状态管理
  const [comments, setComments] = useState([]);
  const [loading, setLoading] = useState(false);
  const [commentText, setCommentText] = useState('');
  const [submitting, setSubmitting] = useState(false);
  const [totalCount, setTotalCount] = useState(0); // 总评论数（从后端获取）

  // 加载评论列表
  const loadComments = useCallback(async () => {
    if (!eventId) return;

    setLoading(true);
    try {
      // 加载第1页，每页5条评论
      const result = await eventService.getPosts(eventId, 'latest', 1, 5);
      if (result.success) {
        setComments(result.data || []);
        // 保存总评论数（从 pagination.total 读取）
        setTotalCount(result.pagination?.total || result.data?.length || 0);
        logger.info('EventCommentSection', '评论加载成功', {
          eventId,
          count: result.data?.length || 0,
          total: result.pagination?.total || 0,
        });
      }
    } catch (error) {
      logger.error('EventCommentSection', 'loadComments', error, { eventId });
      toast({
        title: '加载评论失败',
        description: error.message || '请稍后重试',
        status: 'error',
        duration: 3000,
        isClosable: true,
      });
    } finally {
      setLoading(false);
    }
  }, [eventId, toast]);

  // 发表评论
  const handleSubmitComment = useCallback(async () => {
    if (!commentText.trim()) {
      toast({
        title: '请输入评论内容',
        status: 'warning',
        duration: 2000,
        isClosable: true,
      });
      return;
    }

    setSubmitting(true);
    try {
      const result = await eventService.createPost(eventId, {
        content: commentText.trim(),
        content_type: 'text',
      });

      if (result.success) {
        // 乐观更新：立即将新评论添加到本地 state，避免重新加载导致的闪烁
        const newComment = {
          id: result.data?.id || `comment_optimistic_${Date.now()}`,
          content: commentText.trim(),
          content_type: 'text',
          author: {
            id: user?.id || 'current_user',
            username: user?.username || '当前用户',
            avatar: user?.avatar || null,
          },
          created_at: new Date().toISOString(),
          likes_count: 0,
          is_liked: false,
        };

        // 将新评论追加到列表末尾（最新评论在底部）
        setComments([...comments, newComment]);
        // 总评论数 +1
        setTotalCount(totalCount + 1);

        toast({
          title: '评论发布成功',
          status: 'success',
          duration: 2000,
          isClosable: true,
        });
        setCommentText(''); // 清空输入框
        // ✅ 不再调用 loadComments()，避免 loading 状态导致高度闪烁

        logger.info('EventCommentSection', '评论发布成功（乐观更新）', {
          eventId,
          content: commentText.trim(),
          commentId: newComment.id,
        });
      } else {
        throw new Error(result.message || '评论发布失败');
      }
    } catch (error) {
      logger.error('EventCommentSection', 'handleSubmitComment', error, { eventId });
      toast({
        title: '评论发布失败',
        description: error.message || '请稍后重试',
        status: 'error',
        duration: 3000,
        isClosable: true,
      });
    } finally {
      setSubmitting(false);
    }
  }, [eventId, commentText, toast, comments, user, totalCount]);

  // 初始加载评论
  useEffect(() => {
    loadComments();
  }, [loadComments]);

  return (
    <Box>
      {/* 标题栏 */}
      <HStack
        spacing={3}
        mb={4}
        p={3}
        bg={sectionBg}
        borderRadius="md"
      >
        <Heading size="sm" color={headingColor}>
          讨论区
        </Heading>
        <Badge colorScheme="blue" fontSize="sm" borderRadius="full" px={2}>
          {totalCount} 条评论
        </Badge>
      </HStack>

      <Divider borderColor={dividerColor} mb={4} />

      {/* 评论列表 */}
      <Box mb={4}>
        <CommentList comments={comments} loading={loading} />
      </Box>

      {/* 评论输入框（仅登录用户显示） */}
      {user && (
        <Box>
          <Divider borderColor={dividerColor} mb={4} />
          <CommentInput
            value={commentText}
            onChange={(e) => setCommentText(e.target.value)}
            onSubmit={handleSubmitComment}
            isSubmitting={submitting}
            maxLength={500}
            placeholder="说点什么..."
          />
        </Box>
      )}
    </Box>
  );
};

export default EventCommentSection;