Squashed commit of the following:

commit 688c5426e8793b808b9c75c9a19733af0a402fcb
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 16:25:14 2024 +0300

    Switch to port 8080

commit c39249f6528ec76686a9382d1dc375c07d1d5044
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 16:24:59 2024 +0300

    Switch to alpine image

commit 5318d7ec3f4f3d205549cf6732fa5b066a1d0a36
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 15:40:14 2024 +0300

    Add docker

commit b6cd60a973da26bc92cf1fb45b4d2396b7ce56ea
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 15:00:12 2024 +0300

    Delete asynchrony

commit 44a194e6d27312f3b8dd0b9c9c02d873e06e0b22
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 14:59:29 2024 +0300

    Add Equals and GetHasCode methods overrides to ProductQuantity class

commit a274eadd313e12f11cc84d32e5030bbc5b187f8c
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 14:58:37 2024 +0300

    Add parsers tests

commit 4f969e70d9716d8ddb4f4efedd466846289d7e2b
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sun Jul 21 14:57:55 2024 +0300

    Update product tests

commit 2485e20d0e93bed562f929055b6867dc2574a95b
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sat Jul 20 19:34:19 2024 +0300

    Implement Excel parser

commit 30f2e28c87a4d961c1f1fc48fbd72334905bf4ed
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Sat Jul 20 16:58:35 2024 +0300

    Implement csv parser

commit 08e86b43c0829de341dc3d24fbe01aadbed2e173
Author: Serghei Cebotari <serghei@cebotari.ru>
Date:   Thu Jul 18 21:01:28 2024 +0300

    Edit port number

1 files changed, 76 insertions, 0 deletions

diff --git a/RhSolutions.SkuParser.Api/Services/ExcelParser.cs b/RhSolutions.SkuParser.Api/Services/ExcelParser.cs
new file mode 100644
index 0000000..27b10bd
--- /dev/null
+++ b/RhSolutions.SkuParser.Api/Services/ExcelParser.cs
@@ -0,0 +1,76 @@
+using ClosedXML.Excel;
+using RhSolutions.SkuParser.Models;
+
+namespace RhSolutions.SkuParser.Services;
+
+public class ExcelParser : ISkuParser
+{
+	public IEnumerable<ProductQuantity> ParseProducts(IFormFile file)
+	{
+		using XLWorkbook workbook = new(file.OpenReadStream());
+		IXLWorksheet ws = workbook.Worksheet(1);
+
+		var leftTop = ws.FirstCellUsed()?.Address;
+		var rightBottom = ws.LastCellUsed()?.Address;
+		if (new object?[] { leftTop, rightBottom }.Any(x => x == null))
+		{
+			throw new ArgumentException($"Таблица пуста: {file.FileName}");
+		}
+
+		var lookupRange = ws.Range(leftTop, rightBottom).RangeUsed();
+		var columns = lookupRange.Columns();
+
+		var skuColumnQuantity = columns
+			.Select(column => new
+			{
+				Column = column,
+				Products = column.CellsUsed()
+					.Select(cell => !cell.HasFormula && Product.TryParse(cell.Value.ToString(), out Product? p) ? p : null)
+			})
+			.Select(c => new { c.Column, SkuCount = c.Products.Count(p => p != null) })
+			.Aggregate((l, r) => l.SkuCount > r.SkuCount ? l : r);
+		var skuColumn = skuColumnQuantity.SkuCount > 0 ? skuColumnQuantity.Column : null;
+
+		if (skuColumn == null)
+		{
+			throw new ArgumentException($"Столбец с артикулом не определен: {file.FileName}");
+		}
+
+		var quantityColumn = lookupRange.Columns().Skip(skuColumn.ColumnNumber())
+			.Select(column => new
+			{
+				Column = column,
+				IsColumnWithNumbers = column.CellsUsed()
+					.Count(cell => cell.Value.IsNumber == true) > column.CellsUsed().Count() / 4
+			})
+			.First(x => x.IsColumnWithNumbers)
+			.Column;
+
+		if (quantityColumn == null)
+		{
+			throw new ArgumentException($"Столбец с количеством не определен: {file.FileName}");
+		}
+
+		List<ProductQuantity> result = new();
+		var rows = quantityColumn.CellsUsed().Select(x => x.Address.RowNumber);
+		
+		foreach (var row in rows)
+		{
+			var quantity = quantityColumn.Cell(row).Value;
+			var sku = skuColumn.Cell(row).Value;
+			
+			if (quantity.IsNumber 
+				&& Product.TryParse(sku.ToString(), out Product? p))
+			{
+				ProductQuantity pq = new()
+				{
+					Product = p!,
+					Quantity = quantity.GetNumber()
+				};
+				result.Add(pq);
+			}
+		}
+
+		return result;
+	}
+}