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QWERTYkez.ExcelProcessor/Editors/ExcelBook.cs

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+namespace QWERTYkez.ExcelProcessor.Editors;
+
+/// <summary>
+/// Внутренняя реализация <see cref="IBook"/>, которая делегирует вызовы к <see cref="ExcelWriter"/>.
+/// Используется в ситуациях, когда требуется отдельный объект книги (например, в <see cref="IExcelWriter.Edit"/>).
+/// </summary>
+internal sealed class ExcelBook : IBook
+{
+    internal readonly ExcelWriter Writer;
+
+    /// <summary>
+    /// Инициализирует обёртку книги.
+    /// </summary>
+    /// <param name="writer">Реальный процессор Excel (реализует IBook).</param>
+    internal ExcelBook(ExcelWriter writer)
+    {
+        Writer = writer;
+    }
+
+    /// <inheritdoc />
+    public IReadOnlyList<ISheet> GetSheets() => Writer.GetSheets();
+
+    /// <inheritdoc />
+    public ISheet? Sheet(string name) => Writer.Sheet(name);
+
+    /// <inheritdoc />
+    public bool TryGetSheet(string name, out ISheet sheet) => Writer.TryGetSheet(name, out sheet);
+
+    /// <inheritdoc />
+    public bool TryAddSheet(string name, Action<ISheet>? edit = null) => Writer.TryAddSheet(name, edit);
+
+    /// <inheritdoc />
+    public bool TryRemoveSheet(string name) => Writer.TryRemoveSheet(name);
+
+    /// <inheritdoc />
+    public bool TryRemoveSheet(ISheet sheet) => Writer.TryRemoveSheet(sheet);
+
+    /// <inheritdoc />
+    public IReadOnlyList<NumberFormatPattern> GetNumberFormats() => Writer.GetNumberFormats();
+
+    /// <inheritdoc />
+    public NumberFormatPattern CreateNumberFormat(string format) => Writer.CreateNumberFormat(format);
+}