gui-cs.Terminal.Gui/Terminal.Gui/Drawing/Cell.cs

namespace Terminal.Gui;

/// <summary>
///     Represents a single row/column in a Terminal.Gui rendering surface (e.g. <see cref="LineCanvas"/> and
///     <see cref="ConsoleDriver"/>).
/// </summary>
public record struct Cell ()
{

    /// <summary>The attributes to use when drawing the Glyph.</summary>
    public Attribute? Attribute { get; set; } = null;

    /// <summary>
    ///     Gets or sets a value indicating whether this <see cref="T:Terminal.Gui.Cell"/> has been modified since the
    ///     last time it was drawn.
    /// </summary>
    public bool IsDirty { get; set; } = false;

    private Rune _rune = default;

    /// <summary>The character to display. If <see cref="Rune"/> is <see langword="null"/>, then <see cref="Rune"/> is ignored.</summary>
    public Rune Rune
    {
        get => _rune;
        set
        {
            CombiningMarks.Clear ();
            _rune = value;
        }
    }

    /// <summary>
    ///     The combining marks for <see cref="Rune"/> that when combined makes this Cell a combining sequence. If
    ///     <see cref="CombiningMarks"/> empty, then <see cref="CombiningMarks"/> is ignored.
    /// </summary>
    /// <remarks>
    ///     Only valid in the rare case where <see cref="Rune"/> is a combining sequence that could not be normalized to a
    ///     single Rune.
    /// </remarks>
    internal List<Rune> CombiningMarks { get; } = new ();

    /// <inheritdoc/>
    public override string ToString () { return $"[{Rune}, {Attribute}]"; }
}