Fix build on .NET Framework

Author: manfromarce

README.md

@@ -31,7 +31,7 @@ You can also consider the following libraries for documents creation and manipul
 
 ### Requirements
 
-- .NET 8, 9, 10 and .NET Framework 4.6.2 and higher are supported, but tests are mostly performed on .NET 8 and above.
+- Supported targets are .NET 8, 9, 10 and .NET Framework 4.6.2 (minimum netfx version still supported).  
 - DocSharp.SystemDrawing is for Windows only (.NET Framework or net*-windows), as System.Drawing.Common is only supported on Windows; while DocSharp.ImageSharp is cross-platform for .NET 8+ (ImageSharp does not support .NET Framework).
 
 ### Usage

src/DocSharp.Epub/EpubToDocxConverter.cs

@@ -7,7 +7,7 @@
 using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 using System.Xml.Linq;
-using DocSharp.Xml;
+using DocSharp.Helpers;
 using DocumentFormat.OpenXml;
 using DocumentFormat.OpenXml.Packaging;
 using DocumentFormat.OpenXml.Wordprocessing;
@@ -96,6 +96,8 @@ public async Task BuildDocxAsync(Stream input, WordprocessingDocument targetDocu
             tempDir += Path.DirectorySeparatorChar; 
         try
         {
+            if (Directory.Exists(tempDir))
+                Directory.Delete(tempDir);
             Directory.CreateDirectory(tempDir);            
         }
         catch (Exception ex)
@@ -106,8 +108,18 @@ public async Task BuildDocxAsync(Stream input, WordprocessingDocument targetDocu
         try
         {
             // Extract EPUB to temp directory
-            ZipFile.ExtractToDirectory(input, tempDir, overwriteFiles: true);
+            using (var zip = new ZipArchive(input, ZipArchiveMode.Read, leaveOpen: true))
+            {
+                zip.ExtractToDirectory(tempDir);
+            }
+        }
+        catch (Exception ex)
+        {
+            throw new SystemException($"Unable to extract EPUB to the temp directory. This step is necessary for EPUB processing. Details: {ex.Message}");
+        }
 
+        try
+        {
             // Initialize document
             var mainPart = targetDocument.MainDocumentPart ?? targetDocument.AddMainDocumentPart();
             mainPart.Document ??= new Document();