UCCFile.cs

using System.IO;
using System.IO.Compression;
using SkiaSharp;

namespace PangLib.UCC;

/// <summary>
/// Main UCC file class
/// </summary>
public class UCCFile
{
    /// <summary>
    /// ZIPArchive instance for the UCC file containing the self-design parts
    /// </summary>
    private ZipArchive ZIPFile;

    /// <summary>
    /// Constructor for UCC file instance
    /// </summary>
    /// <param name="data">Stream containing the UCC file data</param>
    public UCCFile(Stream data)
    {
        ZIPFile = new ZipArchive(data);
    }
        
    /// <summary>
    /// Get the specified entry of the UCC file and return it as a bitmap
    /// </summary>
    /// <param name="entryName">Name of the entry</param>
    /// <returns>Bitmap instance of the specified entry</returns>
    public SKBitmap GetBitmapFromFileEntry(string entryName)
    {
        int width;
        int height;
        int posX = 0;
        int posY = 0;

        ZipArchiveEntry entry = ZIPFile.GetEntry(entryName);

        MemoryStream memoryStream = new MemoryStream();
        entry?.Open().CopyTo(memoryStream);
        memoryStream.Position = 0;

        if (memoryStream.Length > 65536)
        {
            width = 256;
            height = 256;
        }
        else if (memoryStream.Length > 32768)
        {
            width = 128;
            height = 64;
        }
        else if (entryName == "icon")
        {
            width = 64;
            height = 84;
        }
        else
        {
            width = 128;
            height = 128;
        }

        SKBitmap bitmap = new SKBitmap(width, height);

        using (BinaryReader reader = new BinaryReader(memoryStream))
        {
            while (reader.BaseStream.Position < reader.BaseStream.Length)
            {
                int loopCount = 3;

                if (entryName == "icon")
                {
                    loopCount = 4;
                }

                byte[] hexColor = new byte[4];

                for (byte i = 0; i < loopCount; i++)
                {
                    hexColor[i] = reader.ReadByte();
                }

                SKColor color = new SKColor(hexColor[2], hexColor[1], hexColor[0], entryName == "icon" ? hexColor[3] : (byte) 255);

                bitmap.SetPixel(posX, posY, color);

                posX++;

                if (posX != width)
                {
                    continue;
                }
                    
                posY++;
                posX = 0;
            }
        }

        return bitmap;
    }
}