File size: 5,042 Bytes
fab29d7 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 |
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using VersOne.Epub.Environment;
using VersOne.Epub.Options;
namespace VersOne.Epub.Internal
{
internal class EpubLocalContentLoader : EpubContentLoader
{
private readonly ContentReaderOptions contentReaderOptions;
private readonly IZipFile epubFile;
private readonly string contentDirectoryPath;
private readonly Dictionary<string, ReplacementContentFileEntry> replacementContentFileEntries;
public EpubLocalContentLoader(IEnvironmentDependencies environmentDependencies, IZipFile epubFile, string contentDirectoryPath, ContentReaderOptions? contentReaderOptions = null)
: base(environmentDependencies)
{
this.epubFile = epubFile ?? throw new ArgumentNullException(nameof(epubFile));
this.contentDirectoryPath = contentDirectoryPath ?? throw new ArgumentNullException(nameof(contentDirectoryPath));
this.contentReaderOptions = contentReaderOptions ?? new ContentReaderOptions();
replacementContentFileEntries = new Dictionary<string, ReplacementContentFileEntry>();
}
public override async Task<byte[]> LoadContentAsBytesAsync(EpubContentFileRefMetadata contentFileRefMetadata)
{
IZipFileEntry contentFileEntry = GetContentFileEntry(contentFileRefMetadata);
byte[] content = new byte[(int)contentFileEntry.Length];
using (Stream contentStream = contentFileEntry.Open())
using (MemoryStream memoryStream = new(content))
{
await contentStream.CopyToAsync(memoryStream).ConfigureAwait(false);
}
return content;
}
public override async Task<string> LoadContentAsTextAsync(EpubContentFileRefMetadata contentFileRefMetadata)
{
using Stream contentStream = GetContentFileEntry(contentFileRefMetadata).Open();
using StreamReader streamReader = new(contentStream);
return await streamReader.ReadToEndAsync().ConfigureAwait(false);
}
public override Task<Stream> GetContentStreamAsync(EpubContentFileRefMetadata contentFileRefMetadata)
{
return Task.FromResult(GetContentFileEntry(contentFileRefMetadata).Open());
}
private IZipFileEntry GetContentFileEntry(EpubContentFileRefMetadata contentFileRefMetadata)
{
if (replacementContentFileEntries.TryGetValue(contentFileRefMetadata.Key, out ReplacementContentFileEntry existingReplacementContentFileEntry))
{
return existingReplacementContentFileEntry;
}
if (epubFile.IsDisposed)
{
throw new ObjectDisposedException(nameof(epubFile), "EPUB file stored within this local content file loader has been disposed.");
}
ReplacementContentFileEntry? newReplacementContentFileEntry = null;
string contentFilePath = ContentPathUtils.Combine(contentDirectoryPath, contentFileRefMetadata.Key);
IZipFileEntry? contentFileEntry = epubFile.GetEntry(contentFilePath);
if (contentFileEntry == null)
{
newReplacementContentFileEntry = RequestReplacementContentFileEntry(contentFileRefMetadata, contentFilePath);
contentFileEntry = newReplacementContentFileEntry;
}
if (contentFileEntry == null)
{
throw new EpubContentException($"EPUB parsing error: file \"{contentFilePath}\" was not found in the EPUB file.", contentFilePath);
}
if (contentFileEntry.Length > Int32.MaxValue)
{
throw new EpubContentException($"EPUB parsing error: file \"{contentFilePath}\" is larger than 2 GB.", contentFilePath);
}
if (newReplacementContentFileEntry != null)
{
replacementContentFileEntries.Add(contentFileRefMetadata.Key, newReplacementContentFileEntry);
}
return contentFileEntry;
}
private ReplacementContentFileEntry? RequestReplacementContentFileEntry(EpubContentFileRefMetadata contentFileRefMetadata, string contentFilePath)
{
ContentFileMissingEventArgs contentFileMissingEventArgs =
new(contentFileRefMetadata.Key, contentFilePath, contentFileRefMetadata.ContentType, contentFileRefMetadata.ContentMimeType);
contentReaderOptions.RaiseContentFileMissingEvent(contentFileMissingEventArgs);
if (contentFileMissingEventArgs.ReplacementContentStream != null)
{
return new ReplacementContentFileEntry(contentFileMissingEventArgs.ReplacementContentStream);
}
else if (contentFileMissingEventArgs.SuppressException)
{
return new ReplacementContentFileEntry(new MemoryStream());
}
return null;
}
}
}
|