MyAvaloniaDemo/AuroraDesk.Presentation/Converters/PlinkMessageConverters.cs

using System;
using System.Globalization;
using AuroraDesk.Core.Entities;
using AuroraDesk.Presentation.ViewModels.Pages;
using Avalonia.Data.Converters;
using Avalonia.Media;

namespace AuroraDesk.Presentation.Converters;

/// <summary>
/// 根据 Plink 消息的方向与状态返回不同的背景色
/// </summary>
public sealed class PlinkMessageBackgroundConverter : IValueConverter
{
    private static readonly SolidColorBrush IncomingBrush = SolidColorBrush.Parse("#DCFCE7");
    private static readonly SolidColorBrush OutgoingBrush = SolidColorBrush.Parse("#DBEAFE");
    private static readonly SolidColorBrush ErrorBrush = SolidColorBrush.Parse("#FEE2E2");
    private static readonly SolidColorBrush SystemBrush = SolidColorBrush.Parse("#F3F4F6");

    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
    {
        if (value is PlinkMessageEntry entry)
        {
            if (entry.IsError)
            {
                return ErrorBrush;
            }

            return entry.Direction switch
            {
                PlinkMessageDirection.Incoming => IncomingBrush,
                PlinkMessageDirection.Outgoing => OutgoingBrush,
                PlinkMessageDirection.System => SystemBrush,
                _ => SystemBrush
            };
        }

        if (value is PlinkMessage message)
        {
            if (message.IsError)
            {
                return ErrorBrush;
            }

            return message.Direction switch
            {
                PlinkMessageDirection.Incoming => IncomingBrush,
                PlinkMessageDirection.Outgoing => OutgoingBrush,
                PlinkMessageDirection.System => SystemBrush,
                _ => SystemBrush
            };
        }

        return SystemBrush;
    }

    public object ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
    {
        throw new NotSupportedException();
    }
}