xianyan/lib/core/utils/extensions.dart

/// ============================================================
/// 闲言APP — 通用扩展方法
/// 创建时间: 2026-04-20
/// 更新时间: 2026-05-16
/// 作用: String / BuildContext / Color 等常用扩展
/// 上次更新: RegExp() → regex() 消除 Dart 3.11 废弃警告
/// ============================================================

import 'package:flutter/material.dart';
import 'package:xianyan/core/utils/pattern_utils.dart';

import 'device_detection.dart';

// ============================================================
// String 扩展
// ============================================================

/// 字符串扩展方法
extension StringX on String {
  /// 是否为空白 (null 或纯空格)
  bool get isBlank => trim().isEmpty;

  /// 是否非空白
  bool get isNotBlank => trim().isNotEmpty;

  /// 截断到指定长度
  String ellipsis(int maxLength, {String suffix = '…'}) {
    if (length <= maxLength) return this;
    return '${substring(0, maxLength)}$suffix';
  }

  /// 首字母大写
  String get capitalize {
    if (isEmpty) return this;
    return '${this[0].toUpperCase()}${substring(1)}';
  }

  /// 去除HTML标签，保留纯文本
  String get stripHtml {
    if (isEmpty) return this;
    var result = this;
    result = result.replaceAll(regex(r'<br\s*/?>', caseSensitive: false), '\n');
    result = result.replaceAll(regex(r'<p\s*/?>', caseSensitive: false), '\n');
    result = result.replaceAll(regex(r'</p>', caseSensitive: false), '');
    result = result.replaceAll(
      regex(r'<strong[^>]*>(.*?)</strong>', caseSensitive: false, dotAll: true),
      r'$1',
    );
    result = result.replaceAll(
      regex(r'<em[^>]*>(.*?)</em>', caseSensitive: false, dotAll: true),
      r'$1',
    );
    result = result.replaceAll(regex(r'<[^>]*>'), '');
    result = result.replaceAll(regex(r'\n{3,}'), '\n\n');
    return result.trim();
  }

  /// 解码HTML实体
  String get decodeHtmlEntities {
    if (isEmpty) return this;
    return replaceAll('&amp;', '&')
        .replaceAll('&lt;', '<')
        .replaceAll('&gt;', '>')
        .replaceAll('&quot;', '"')
        .replaceAll('&#39;', "'")
        .replaceAll('&nbsp;', ' ');
  }

  /// 去除HTML标签 + 解码HTML实体
  String get cleanHtml => stripHtml.decodeHtmlEntities;
}

// ============================================================
// BuildContext 扩展
// ============================================================

/// BuildContext 扩展方法
extension BuildContextX on BuildContext {
  /// 获取主题
  ThemeData get theme => Theme.of(this);

  /// 获取颜色方案
  ColorScheme get colorScheme => Theme.of(this).colorScheme;

  /// 获取 TextTheme
  TextTheme get textTheme => Theme.of(this).textTheme;

  /// 获取屏幕尺寸
  Size get screenSize => MediaQuery.sizeOf(this);

  /// 获取屏幕宽度
  double get screenWidth => screenSize.width;

  /// 获取屏幕高度
  double get screenHeight => screenSize.height;

  /// 获取底部安全区域
  double get bottomPadding => MediaQuery.paddingOf(this).bottom;

  /// 获取顶部安全区域
  double get topPadding => MediaQuery.paddingOf(this).top;

  /// 是否为小屏 (< mobile断点)
  bool get isSmallScreen => screenWidth < Breakpoints.mobile;

  /// 是否为中屏 (mobile - desktop断点)
  bool get isMediumScreen =>
      screenWidth >= Breakpoints.mobile && screenWidth < Breakpoints.desktop;

  /// 是否为大屏 (>= desktop断点)
  bool get isLargeScreen => screenWidth >= Breakpoints.desktop;

  /// 是否横屏
  bool get isLandscape => screenWidth > screenHeight;

  /// 是否竖屏
  bool get isPortrait => screenWidth < screenHeight;

  /// 屏幕尺寸分类
  ScreenSizeClass get sizeClass =>
      DeviceDetection.sizeClassFromWidth(screenWidth);

  /// 布局列数
  int get layoutColumns => sizeClass.layoutColumns;
}

// ============================================================
// Color 扩展
// ============================================================

/// Color 扩展方法
extension ColorX on Color {
  /// 调整透明度 (0.0 - 1.0)
  Color withAlpha(double alpha) {
    return withValues(alpha: alpha.clamp(0.0, 1.0));
  }
}

// ============================================================
// DateTime 扩展
// ============================================================

/// DateTime 扩展方法
extension DateTimeX on DateTime {
  /// 友好时间文本 (如 "3分钟前")
  String get timeAgo {
    final now = DateTime.now();
    final diff = now.difference(this);

    if (diff.inSeconds < 60) return '刚刚';
    if (diff.inMinutes < 60) return '${diff.inMinutes}分钟前';
    if (diff.inHours < 24) return '${diff.inHours}小时前';
    if (diff.inDays < 30) return '${diff.inDays}天前';
    if (diff.inDays < 365) return '${diff.inDays ~/ 30}个月前';
    return '${diff.inDays ~/ 365}年前';
  }

  /// 格式化日期 yyyy-MM-dd
  String get formatDate =>
      '$year-${month.toString().padLeft(2, '0')}-${day.toString().padLeft(2, '0')}';

  /// 格式化时间 HH:mm
  String get formatTime =>
      '${hour.toString().padLeft(2, '0')}:${minute.toString().padLeft(2, '0')}';
}