/// <summary>
/// Given a book, typically one in a temporary folder made just for exporting (or testing),
/// and given the set of fonts found while creating that book and removing hidden elements,
/// find the files needed for those fonts.
/// Copy the font file for the normal style of that font family from the system font folder,
/// if permitted; or post a warning in progress if we can't embed it.
/// Create an extra css file (fonts.css) which tells the book to find the font files for those font families
/// in the local folder, and insert a link to it into the book.
/// </summary>
/// <param name="fontFileFinder">use new FontFinder() for real, or a stub in testing</param>
public static void EmbedFonts(Book.Book book, IWebSocketProgress progress, HashSet <string> fontsWanted, IFontFinder fontFileFinder)
{
const string defaultFont = "Andika New Basic"; // already in BR, don't need to embed or make rule.
fontsWanted.Remove(defaultFont);
PublishHelper.CheckFontsForEmbedding(progress, fontsWanted, fontFileFinder, out List <string> filesToEmbed, out HashSet <string> badFonts);
foreach (var file in filesToEmbed)
{
// Enhance: do we need to worry about problem characters in font file names?
var dest = Path.Combine(book.FolderPath, Path.GetFileName(file));
RobustFile.Copy(file, dest);
}
// Create the fonts.css file, which tells the browser where to find the fonts for those families.
var sb = new StringBuilder();
foreach (var font in fontsWanted)
{
if (badFonts.Contains(font))
{
continue;
}
var group = fontFileFinder.GetGroupForFont(font);
if (group != null)
{
EpubMaker.AddFontFace(sb, font, "normal", "normal", group.Normal);
}
// We don't need (or want) a rule to use Andika instead.
// The reader typically WILL use Andika, because we have a rule making it the default font
// for the whole body of the document, and BloomReader always has it available.
// However, it's possible that although we aren't allowed to embed the desired font,
// the device actually has it installed. In that case, we want to use it.
}
RobustFile.WriteAllText(Path.Combine(book.FolderPath, "fonts.css"), sb.ToString());
// Tell the document to use the new stylesheet.
book.OurHtmlDom.AddStyleSheet("fonts.css");
// Repair defaultLangStyles.css and other places in the output book if needed.
if (badFonts.Any())
{
PublishHelper.FixCssReferencesForBadFonts(book.FolderPath, defaultFont, badFonts);
PublishHelper.FixXmlDomReferencesForBadFonts(book.OurHtmlDom.RawDom, defaultFont, badFonts);
}
}
