frontend/src/screens/message/components/ChatScreen/ChatHeader.tsx

/**
 * 聊天头部组件
 * 支持响应式布局（宽屏下显示更多信息）
 */

import React, { useMemo } from 'react';
import { View, TouchableOpacity, StyleSheet } from 'react-native';
import { SafeAreaView } from 'react-native-safe-area-context';
import { MaterialCommunityIcons } from '@expo/vector-icons';
import { Avatar, Text } from '../../../../components/common';
import { colors, spacing } from '../../../../theme';
import { chatScreenStyles as baseStyles } from './styles';
import { useResponsive, useBreakpointGTE } from '../../../../hooks/useResponsive';
import { ChatHeaderProps } from './types';

export const ChatHeader: React.FC<ChatHeaderProps> = ({
  isGroupChat,
  groupInfo,
  otherUser,
  routeGroupName,
  typingHint,
  onBack,
  onTitlePress,
  onMorePress,
  onGroupInfoPress,
  isWideScreen: propIsWideScreen,
}) => {
  // 响应式布局
  const { width } = useResponsive();
  // 使用 768px 作为大屏幕和小屏幕的分界线
  const isWideScreenHook = useBreakpointGTE('lg');
  // 优先使用 props 传入的 isWideScreen，否则使用 hook
  const isWideScreen = propIsWideScreen !== undefined ? propIsWideScreen : isWideScreenHook;
  
  // 合并样式
  const styles = useMemo(() => {
    return StyleSheet.create({
      ...baseStyles,
      headerContainer: {
        ...baseStyles.headerContainer,
        maxWidth: isWideScreen ? 1200 : undefined,
        alignSelf: isWideScreen ? 'center' : undefined,
        width: isWideScreen ? '100%' : undefined,
      },
      header: {
        ...baseStyles.header,
        paddingHorizontal: isWideScreen ? spacing.xl : spacing.md,
      },
      headerName: {
        ...baseStyles.headerName,
        fontSize: isWideScreen ? 19 : 17,
      },
      memberCount: {
        ...baseStyles.memberCount,
        fontSize: isWideScreen ? 14 : 13,
      },
      typingHint: {
        ...baseStyles.typingHint,
        fontSize: isWideScreen ? 13 : 12,
      },
    });
  }, [isWideScreen]);

  // 获取显示标题
  const getDisplayTitle = () => {
    if (isGroupChat) {
      return routeGroupName || groupInfo?.name || '群聊';
    }
    return otherUser?.nickname || '用户';
  };

  return (
    <SafeAreaView edges={['top']} style={styles.headerContainer}>
      <View style={styles.header}>
        {/* 大屏幕（>= 768px）时隐藏返回按钮 */}
        {!isWideScreen ? (
          <TouchableOpacity
            style={styles.backButton}
            onPress={onBack}
          >
            <MaterialCommunityIcons name="arrow-left" size={22} color={colors.primary.dark} />
          </TouchableOpacity>
        ) : (
          <View style={styles.backButton} />
        )}
        
        <View style={styles.headerCenter}>
          <TouchableOpacity
            style={styles.titleRow}
            onPress={onTitlePress}
            activeOpacity={0.75}
          >
            {isGroupChat ? (
              <>
                <View style={styles.titleLeading}>
                  <MaterialCommunityIcons name="account-group" size={20} color={colors.primary.main} />
                </View>
                <View style={styles.titleContent}>
                  <Text style={styles.headerName} numberOfLines={1}>{getDisplayTitle()}</Text>
                  <View style={styles.subtitleRow}>
                    <Text style={styles.memberCount}>{groupInfo?.member_count || 0}位成员</Text>
                    {typingHint && (
                      <Text style={styles.typingHint} numberOfLines={1}>{typingHint}</Text>
                    )}
                  </View>
                </View>
              </>
            ) : (
              <>
                <Avatar
                  source={otherUser?.avatar || null}
                  size={32}
                  name={otherUser?.nickname || ''}
                />
                <View style={styles.titleContent}>
                  <Text style={styles.headerName} numberOfLines={1}>{getDisplayTitle()}</Text>
                  {typingHint && (
                    <View style={styles.subtitleRow}>
                      <Text style={styles.typingHint} numberOfLines={1}>{typingHint}</Text>
                    </View>
                  )}
                </View>
              </>
            )}
          </TouchableOpacity>
        </View>
        
        {/* 大屏幕 + 群聊时显示群信息按钮，否则显示三点菜单 */}
        {isWideScreen && isGroupChat && onGroupInfoPress ? (
          <TouchableOpacity
            style={styles.moreButton}
            onPress={onGroupInfoPress}
          >
            <MaterialCommunityIcons name="dots-horizontal" size={22} color="#667085" />
          </TouchableOpacity>
        ) : (
          <TouchableOpacity
            style={styles.moreButton}
            onPress={onMorePress}
          >
            <MaterialCommunityIcons name="dots-horizontal" size={22} color="#667085" />
          </TouchableOpacity>
        )}
      </View>
    </SafeAreaView>
  );
};

export default ChatHeader;