public void ResolveRelativePathTests()
{
var chapter = new EbookChapter("", "", "Text/text0001.html");
Assert.AreEqual("Text/text0002.html", chapter.ResolveRelativePath("text0002.html"));
Assert.AreEqual("text0002.html", chapter.ResolveRelativePath("../text0002.html"));
Assert.AreEqual("Text/text0002.html", chapter.ResolveRelativePath("../Text/text0002.html"));
Assert.AreEqual("Imgs/cover.png", chapter.ResolveRelativePath("../Imgs/cover.png"));
Assert.AreEqual("cover.png", chapter.ResolveRelativePath("../cover.png"));
chapter = new EbookChapter("", "", "text0001.html");
Assert.AreEqual("text0002.html", chapter.ResolveRelativePath("text0002.html"));
Assert.AreEqual("text0002.html", chapter.ResolveRelativePath("../text0002.html"));
Assert.AreEqual("Text/text0002.html", chapter.ResolveRelativePath("../Text/text0002.html"));
Assert.AreEqual("Imgs/cover.png", chapter.ResolveRelativePath("../Imgs/cover.png"));
Assert.AreEqual("cover.png", chapter.ResolveRelativePath("../cover.png"));
Assert.AreEqual("cover.png", chapter.ResolveRelativePath("/cover.png"));
}
/// <summary>
/// Enumerates all img tags and svg.image tags and extracts image paths. Each image is
/// converted to base64, and inserted directly into the HTML code.
/// </summary>
/// <param name="data"></param>
/// <param name="doc"></param>
/// <param name="chapter"></param>
/// <returns></returns>
private void InlineImages(EpubEbook book, HtmlDocument doc, EbookChapter chapter)
{
var imageData = book.Data.Resources.Images.ToDictionary(k => k.FileName, v => v);
// Find all img and image nodes, and extract their source path
var images = doc.DocumentNode.Descendants("img")
.Select(p => new { Node = p, Src = p.Attributes.FirstOrDefault(c => c.Name == "src") })
.Union(doc.DocumentNode.Descendants("image")
.Select(p => new { Node = p, Src = p.Attributes.FirstOrDefault(c => c.Name == "xlink:href") }))
// Remove images without source
.Where(p => p.Src != null)
// Convert the relative HTML path to an absolute (inside local folder) path
.Select(p => new
{
p.Node,
p.Src,
Path = chapter.ResolveRelativePath(p.Src.Value)
})
// Group by image path to avoid loading and transferring the same image more than once
.GroupBy(p => p.Path);
foreach (var image in images)
{
var imgData = imageData[image.Key];
//var base64 = Base64Helper.Encode(imgData.Content);
//var ctype = imgData.ContentType.ToString().ToLower().Replace("image", "image/"); // From enum "ImageJpeg" to "image/jpeg".
foreach (var element in image)
{
//element.Node.Attributes["src"].Value = $"data:{ctype};base64,{base64}";
var tempPath = book.Info.GetTempPath(imgData.FileName);
if (!System.IO.File.Exists(tempPath))
{
var dir = Path.GetDirectoryName(tempPath);
Directory.CreateDirectory(dir);
System.IO.File.WriteAllBytes(tempPath, imgData.Content);
}
if (element.Node.Attributes.Contains("src"))
{
element.Node.Attributes["src"].Value = tempPath;
}
if (element.Node.Attributes.Contains("xlink:href"))
{
element.Node.Attributes["xlink:href"].Value = tempPath;
}
}
}
}
private void InlineCss(EpubEbook book, HtmlDocument doc, EbookChapter chapter)
{
var internalStyles = doc.DocumentNode.Descendants("style").ToList();
var body = HtmlHelper.GetBody(doc);
foreach (var s in internalStyles)
{
s.Remove();
body.PrependChild(s);
}
var externalStyles = doc.DocumentNode
.Descendants("link")
.Where(p => p.Attributes["rel"].Value.ToLower() == "stylesheet")
.Select(p => p.Attributes["href"].Value)
.ToList();
foreach (var s in externalStyles)
{
var style = book.Data.Resources.Css.FirstOrDefault(p => p.FileName == chapter.ResolveRelativePath(s));
if (style != null)
{
var css = style.TextContent;
foreach (var font in book.Data.Resources.Fonts.Union(book.Data.Resources.Other))
{
var fontPath = PathHelper.CombinePath(style.FileName, font.FileName);
var extractedFontPath = book.Info.GetTempPath(fontPath);
css = css.Replace(fontPath, extractedFontPath);
}
body.PrependChild(HtmlNode.CreateNode("<style>" + css + "</style>"));
}
}
}