PixiEditor/src/PixiEditor/Models/Controllers/BrushLibrary.cs

using Avalonia.Platform;
using PixiEditor.ChangeableDocument.Changeables.Graph.Interfaces;
using PixiEditor.Helpers;
using PixiEditor.Models.BrushEngine;
using PixiEditor.Models.IO;

namespace PixiEditor.Models.Controllers;

internal class BrushLibrary
{
    private List<Brush> brushes = new List<Brush>();
    public IReadOnlyList<Brush> Brushes => brushes;

    private string pathToBrushes;
    public string PathToBrushes => pathToBrushes;

    public BrushLibrary(string pathToBrushes)
    {
        this.pathToBrushes = pathToBrushes;
    }

    private void LoadBuiltIn()
    {
        Uri brushesUri = new Uri("avares://PixiEditor/Data/Brushes/");
        var assets = AssetLoader.GetAssets(brushesUri, null);

        foreach (var asset in assets)
        {
            string localPath = asset.LocalPath;
            if (localPath.EndsWith(".pixi", StringComparison.OrdinalIgnoreCase))
            {
                try
                {
                    var fullUri = new Uri(brushesUri, asset);
                    using var stream = AssetLoader.Open(fullUri);
                    byte[] buffer = new byte[stream.Length];
                    stream.ReadExactly(buffer, 0, buffer.Length);
                    var doc = Importer.ImportDocument(buffer, null);
                    var brush = new Brush(Path.GetFileNameWithoutExtension(localPath), doc);
                    brushes.Add(brush);
                }
                catch (Exception ex)
                {
                    Console.WriteLine($"Failed to load built-in brush from {asset}: {ex.Message}");
                }
            }
        }
    }

    private void LoadBrushesFromPath(string path)
    {
        if (!Directory.Exists(path))
            return;

        var brushFiles = Directory.GetFiles(path, "*.pixi", SearchOption.AllDirectories);
        foreach (var file in brushFiles)
        {
            try
            {
                var doc = Importer.ImportDocument(file, false);
                var brush = new Brush(Path.GetFileNameWithoutExtension(file), doc);
                brushes.Add(brush);
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Failed to load brush from {file}: {ex.Message}");
            }
        }
    }

    public void LoadBrushes()
    {
        LoadBuiltIn();
        LoadBrushesFromPath(pathToBrushes);
    }

    public void Add(Brush brush)
    {
        if (!brushes.Contains(brush))
            brushes.Add(brush);
    }
}