using System;
using System.IO;
using Avalonia.Platform;

namespace Avalonia.Android
{
    internal class WindowingPlatformStub : IWindowingPlatform
    {
        public IWindowImpl CreateWindow() => throw new NotSupportedException();
        public ITopLevelImpl CreateEmbeddableTopLevel() => CreateEmbeddableWindow();

        public IWindowImpl CreateEmbeddableWindow() => throw new NotSupportedException();

        public ITrayIconImpl? CreateTrayIcon() => null;

        public void GetWindowsZOrder(ReadOnlySpan<IWindowImpl> windows, Span<long> zOrder) => throw new NotSupportedException();
    }

    internal class PlatformIconLoaderStub : IPlatformIconLoader
    {
        public IWindowIconImpl LoadIcon(IBitmapImpl bitmap)
        {
            using (var stream = new MemoryStream())
            {
                bitmap.Save(stream);
                return LoadIcon(stream);
            }
        }

        public IWindowIconImpl LoadIcon(Stream stream)
        {
            var ms = new MemoryStream();
            stream.CopyTo(ms);
            return new IconStub(ms);
        }

        public IWindowIconImpl LoadIcon(string fileName)
        {
            using (var file = File.Open(fileName, FileMode.Open))
                return LoadIcon(file);
        }
    }

    internal class IconStub : IWindowIconImpl
    {
        private readonly MemoryStream _ms;

        public IconStub(MemoryStream stream)
        {
            _ms = stream;
        }

        public void Save(Stream outputStream)
        {
            _ms.Position = 0;
            _ms.CopyTo(outputStream);
        }
    }
}