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QWERTYkez.ExcelProcessor/Editors/CellFill.cs

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+namespace QWERTYkez.ExcelProcessor.Editors;
+
+/// <summary>
+/// Определяет заливку (фон) ячейки.
+/// </summary>
+public readonly struct CellFill : IEquatable<CellFill>
+{
+    /// <summary>Цвет фона.</summary>
+    public ExColor? BackgroundColor { get; init; }
+
+    /// <summary>Создаёт элемент Fill для Open XML.</summary>
+    public Fill? ToFill()
+    {
+        if (!BackgroundColor.HasValue || !BackgroundColor.Value.Color.HasValue)
+            return null;
+
+        var c = BackgroundColor.Value.Color.Value;
+        var fill = new Fill
+        {
+            PatternFill = new PatternFill
+            {
+                PatternType = PatternValues.Solid,
+                ForegroundColor = new ForegroundColor { Rgb = $"{c.R:X2}{c.G:X2}{c.B:X2}" }
+            }
+        };
+        return fill;
+    }
+
+    /// <summary>Создаёт CellFill из элемента Fill Open XML.</summary>
+    public static CellFill FromFill(Fill? fill)
+    {
+        if (fill?.PatternFill?.ForegroundColor?.Rgb?.Value is not string rgb || rgb.Length < 6)
+            return default;
+
+        var color = System.Drawing.Color.FromArgb(
+            Convert.ToByte(rgb.Substring(0, 2), 16),
+            Convert.ToByte(rgb.Substring(2, 2), 16),
+            Convert.ToByte(rgb.Substring(4, 2), 16)
+        );
+        return new CellFill { BackgroundColor = new ExColor(color) };
+    }
+
+    public override bool Equals(object? obj) => obj is CellFill other && Equals(other);
+    public bool Equals(CellFill other) => this == other;
+
+    public static bool operator ==(CellFill left, CellFill right) =>
+        Equals(left.BackgroundColor, right.BackgroundColor);
+
+    public static bool operator !=(CellFill left, CellFill right) => !(left == right);
+
+    public override int GetHashCode() =>
+        BackgroundColor?.GetHashCode() ?? 0;
+}