import 'package:flutter/material.dart';
import 'app_colors.dart';

/// Genex Design System - Typography Tokens
///
/// 字体层级：清晰、易读、干净
/// 基于 SF Pro (iOS) / Roboto (Android) 系统字体
class AppTypography {
  AppTypography._();

  static const String _fontFamily = 'SF Pro Display';
  static const String _fontFamilyFallback = 'Roboto';

  // ============================================================
  // Display - 超大标题（启动页/空状态）
  // ============================================================
  static const TextStyle displayLarge = TextStyle(
    fontSize: 34,
    fontWeight: FontWeight.w700,
    height: 1.2,
    letterSpacing: -0.5,
    color: AppColors.textPrimary,
  );

  static const TextStyle displayMedium = TextStyle(
    fontSize: 28,
    fontWeight: FontWeight.w700,
    height: 1.25,
    letterSpacing: -0.3,
    color: AppColors.textPrimary,
  );

  // ============================================================
  // Heading - 页面标题 / 模块标题
  // ============================================================
  static const TextStyle h1 = TextStyle(
    fontSize: 24,
    fontWeight: FontWeight.w700,
    height: 1.3,
    color: AppColors.textPrimary,
  );

  static const TextStyle h2 = TextStyle(
    fontSize: 20,
    fontWeight: FontWeight.w600,
    height: 1.35,
    color: AppColors.textPrimary,
  );

  static const TextStyle h3 = TextStyle(
    fontSize: 17,
    fontWeight: FontWeight.w600,
    height: 1.4,
    color: AppColors.textPrimary,
  );

  // ============================================================
  // Body - 正文
  // ============================================================
  static const TextStyle bodyLarge = TextStyle(
    fontSize: 16,
    fontWeight: FontWeight.w400,
    height: 1.5,
    color: AppColors.textPrimary,
  );

  static const TextStyle bodyMedium = TextStyle(
    fontSize: 14,
    fontWeight: FontWeight.w400,
    height: 1.5,
    color: AppColors.textPrimary,
  );

  static const TextStyle bodySmall = TextStyle(
    fontSize: 12,
    fontWeight: FontWeight.w400,
    height: 1.5,
    color: AppColors.textSecondary,
  );

  // ============================================================
  // Label - 按钮文字/标签/Tab
  // ============================================================
  static const TextStyle labelLarge = TextStyle(
    fontSize: 16,
    fontWeight: FontWeight.w600,
    height: 1.4,
    letterSpacing: 0.2,
    color: AppColors.textPrimary,
  );

  static const TextStyle labelMedium = TextStyle(
    fontSize: 14,
    fontWeight: FontWeight.w500,
    height: 1.4,
    letterSpacing: 0.1,
    color: AppColors.textPrimary,
  );

  static const TextStyle labelSmall = TextStyle(
    fontSize: 12,
    fontWeight: FontWeight.w500,
    height: 1.4,
    letterSpacing: 0.2,
    color: AppColors.textSecondary,
  );

  // ============================================================
  // Caption - 辅助文字
  // ============================================================
  static const TextStyle caption = TextStyle(
    fontSize: 11,
    fontWeight: FontWeight.w400,
    height: 1.4,
    color: AppColors.textTertiary,
  );

  // ============================================================
  // Price - 价格专用
  // ============================================================
  static const TextStyle priceLarge = TextStyle(
    fontSize: 28,
    fontWeight: FontWeight.w700,
    height: 1.2,
    color: AppColors.primary,
  );

  static const TextStyle priceMedium = TextStyle(
    fontSize: 20,
    fontWeight: FontWeight.w700,
    height: 1.2,
    color: AppColors.primary,
  );

  static const TextStyle priceSmall = TextStyle(
    fontSize: 16,
    fontWeight: FontWeight.w600,
    height: 1.2,
    color: AppColors.primary,
  );

  static const TextStyle priceOriginal = TextStyle(
    fontSize: 13,
    fontWeight: FontWeight.w400,
    height: 1.2,
    color: AppColors.textTertiary,
    decoration: TextDecoration.lineThrough,
  );

  // ============================================================
  // Discount Badge - 折扣标签
  // ============================================================
  static const TextStyle discountBadge = TextStyle(
    fontSize: 12,
    fontWeight: FontWeight.w700,
    height: 1.0,
    color: Colors.white,
  );
}