Provide compressed length information for content files

Source/VersOne.Epub.Test/Unit/Content/Loaders/EpubLocalContentLoaderTests.cs

@@ -1,4 +1,5 @@
 using System.Text;
+using VersOne.Epub.Environment;
 using VersOne.Epub.Internal;
 using VersOne.Epub.Options;
 using VersOne.Epub.Test.Unit.Mocks;
@@ -462,11 +463,15 @@ public void LoadContentWithMissingFileAndSuppressExceptionTrueTest()
         public void LoadContentWithMissingFileAndReplacementContentStreamSetTest()
         {
             ContentReaderOptions contentReaderOptions = new();
-            contentReaderOptions.ContentFileMissing += (sender, e) => e.ReplacementContentStream = new MemoryStream(Encoding.UTF8.GetBytes(TEXT_FILE_CONTENT));
+            byte[] replacementFileContent = Encoding.UTF8.GetBytes(TEXT_FILE_CONTENT);
+            contentReaderOptions.ContentFileMissing += (sender, e) => e.ReplacementContentStream = new MemoryStream(replacementFileContent);
             TestZipFile testZipFile = new();
             EpubLocalContentLoader epubLocalContentLoader = CreateEpubLocalContentLoader(testZipFile, contentReaderOptions);
             string textContent = epubLocalContentLoader.LoadContentAsText(TextFileRefMetadata);
             Assert.Equal(TEXT_FILE_CONTENT, textContent);
+            IZipFileEntry replacementFileContentEntry = epubLocalContentLoader.GetContentFileEntry(TextFileRefMetadata);
+            Assert.Equal(replacementFileContent.Length, replacementFileContentEntry.Length);
+            Assert.Equal(replacementFileContent.Length, replacementFileContentEntry.CompressedLength);
         }
 
         [Fact(DisplayName = "Using replacement content multiple times while loading the same content file should succeed")]

Source/VersOne.Epub.Test/Unit/Mocks/Test4GbZipFileEntry.cs

@@ -4,7 +4,11 @@ namespace VersOne.Epub.Test.Unit.Mocks
 {
     internal class Test4GbZipFileEntry : IZipFileEntry
     {
-        public long Length => (long)4 * 1024 * 1024 * 1024;
+        private const long SIZE_4GB = (long)4 * 1024 * 1024 * 1024;
+
+        public long Length => SIZE_4GB;
+
+        public long CompressedLength => SIZE_4GB;
 
         public Stream Open()
         {

Source/VersOne.Epub.Test/Unit/Mocks/TestZipFileEntry.cs

@@ -45,6 +45,8 @@ public long Length
             }
         }
 
+        public long CompressedLength => Length;
+
         public Stream Open()
         {
             if (memoryStream != null)

Source/VersOne.Epub/Content/Loaders/EpubLocalContentLoader.cs

@@ -47,7 +47,7 @@ public override Task<Stream> GetContentStreamAsync(EpubContentFileRefMetadata co
             return Task.FromResult(GetContentFileEntry(contentFileRefMetadata).Open());
         }
 
-        private IZipFileEntry GetContentFileEntry(EpubContentFileRefMetadata contentFileRefMetadata)
+        public IZipFileEntry GetContentFileEntry(EpubContentFileRefMetadata contentFileRefMetadata)
         {
             if (replacementContentFileEntries.TryGetValue(contentFileRefMetadata.Key, out ReplacementContentFileEntry? existingReplacementContentFileEntry))
             {

Source/VersOne.Epub/Content/Loaders/ReplacementContentFileEntry.cs

@@ -19,6 +19,8 @@ public ReplacementContentFileEntry(Stream replacementStream)
 
         public long Length => replacementStreamContent.Length;
 
+        public long CompressedLength => replacementStreamContent.Length;
+
         public Stream Open()
         {
             return new MemoryStream(replacementStreamContent);

Source/VersOne.Epub/Environment/IZipFileEntry.cs

@@ -12,6 +12,11 @@ public interface IZipFileEntry
         /// </summary>
         long Length { get; }
 
+        /// <summary>
+        /// Gets the compressed size of the entry in the ZIP archive.
+        /// </summary>
+        long CompressedLength { get; }
+
         /// <summary>
         /// Opens the entry from the ZIP archive.
         /// </summary>

Source/VersOne.Epub/Environment/Implementation/ZipFileEntry.cs

@@ -15,6 +15,8 @@ public ZipFileEntry(ZipArchiveEntry zipArchiveEntry)
 
         public long Length => zipArchiveEntry.Length;
 
+        public long CompressedLength => zipArchiveEntry.CompressedLength;
+
         public Stream Open()
         {
             return zipArchiveEntry.Open();