private CMap ReadEncoding(DictionaryToken dictionary, out bool isCMapPredefined)
{
isCMapPredefined = false;
CMap result = default(CMap);
if (dictionary.TryGet(NameToken.Encoding, out var value))
{
if (value is NameToken encodingName)
{
var cmap = cMapCache.Get(encodingName.Data);
result = cmap ?? throw new InvalidOperationException("Missing CMap for " + encodingName.Data);
isCMapPredefined = true;
}
else if (value is StreamToken stream)
{
var decoded = stream.Decode(filterProvider);
var cmap = cMapCache.Parse(new ByteArrayInputBytes(decoded), false);
result = cmap ?? throw new InvalidOperationException("Could not read CMap for " + dictionary);
}
else
{
throw new InvalidOperationException("Could not read the encoding, expected a name or a stream but got a: " + value.GetType().Name);
}
}
return(result);
}
private CMap ReadEncoding(DictionaryToken dictionary, out bool isCMapPredefined)
{
isCMapPredefined = false;
CMap result;
if (dictionary.TryGet(NameToken.Encoding, scanner, out NameToken encodingName))
{
var cmap = CMapCache.Get(encodingName.Data);
result = cmap ?? throw new InvalidOperationException($"Missing CMap named {encodingName.Data}.");
isCMapPredefined = true;
}
else if (dictionary.TryGet(NameToken.Encoding, scanner, out StreamToken stream))
{
var decoded = stream.Decode(filterProvider);
var cmap = CMapCache.Parse(new ByteArrayInputBytes(decoded));
result = cmap ?? throw new InvalidOperationException($"Could not read CMap from stream in the dictionary: {dictionary}");
}
else
{
throw new InvalidOperationException(
$"Could not read the encoding, expected a name or a stream but it was not found in the dictionary: {dictionary}");
}
return(result);
}
public IFont Generate(DictionaryToken dictionary, bool isLenientParsing)
{
var baseFont = dictionary.GetNameOrDefault(NameToken.BaseFont);
var cMap = ReadEncoding(dictionary, out var isCMapPredefined);
ICidFont cidFont;
if (TryGetFirstDescendant(dictionary, out var descendantObject))
{
DictionaryToken descendantFontDictionary;
if (descendantObject is IndirectReferenceToken obj)
{
var parsed = DirectObjectFinder.Get<DictionaryToken>(obj, scanner);
descendantFontDictionary = parsed;
}
else
{
descendantFontDictionary = (DictionaryToken) descendantObject;
}
cidFont = ParseDescendant(descendantFontDictionary, isLenientParsing);
}
else
{
throw new InvalidFontFormatException("No descendant font dictionary was declared for this Type 0 font. This dictionary should contain the CIDFont for the Type 0 font. " + dictionary);
}
var (ucs2CMap, isChineseJapaneseOrKorean) = GetUcs2CMap(dictionary, isCMapPredefined, cidFont);
CMap toUnicodeCMap = null;
if (dictionary.ContainsKey(NameToken.ToUnicode))
{
var toUnicodeValue = dictionary.Data[NameToken.ToUnicode];
if (DirectObjectFinder.TryGet<StreamToken>(toUnicodeValue, scanner, out var toUnicodeStream))
{
var decodedUnicodeCMap = toUnicodeStream?.Decode(filterProvider);
if (decodedUnicodeCMap != null)
{
toUnicodeCMap = CMapCache.Parse(new ByteArrayInputBytes(decodedUnicodeCMap), isLenientParsing);
}
}
else if (DirectObjectFinder.TryGet<NameToken>(toUnicodeValue, scanner, out var toUnicodeName))
{
toUnicodeCMap = CMapCache.Get(toUnicodeName.Data);
}
else
{
throw new PdfDocumentFormatException($"Invalid type of toUnicode CMap encountered. Got: {toUnicodeValue}.");
}
}
var font = new Type0Font(baseFont, cidFont, cMap, toUnicodeCMap, ucs2CMap, isChineseJapaneseOrKorean);
return font;
}
private static (CMap, bool isChineseJapaneseOrKorean) GetUcs2CMap(DictionaryToken dictionary, bool isCMapPredefined, ICidFont cidFont)
{
if (!isCMapPredefined)
{
return(null, false);
}
/*
* If the font is a composite font that uses one of the predefined CMaps except Identity–H and Identity–V or whose descendant
* CIDFont uses the Adobe-GB1, Adobe-CNS1, Adobe-Japan1, or Adobe-Korea1 character collection use a UCS2 CMap.
*/
var encodingName = dictionary.GetNameOrDefault(NameToken.Encoding);
if (encodingName == null)
{
return(null, false);
}
var isChineseJapaneseOrKorean = false;
if (cidFont != null && string.Equals(cidFont.SystemInfo.Registry, "Adobe", StringComparison.OrdinalIgnoreCase))
{
isChineseJapaneseOrKorean = string.Equals(cidFont.SystemInfo.Ordering, "GB1", StringComparison.OrdinalIgnoreCase) ||
string.Equals(cidFont.SystemInfo.Ordering, "CNS1", StringComparison.OrdinalIgnoreCase) ||
string.Equals(cidFont.SystemInfo.Ordering, "Japan1", StringComparison.OrdinalIgnoreCase) ||
string.Equals(cidFont.SystemInfo.Ordering, "Korea1", StringComparison.OrdinalIgnoreCase);
}
var isPredefinedIdentityMap = encodingName.Equals(NameToken.IdentityH) || encodingName.Equals(NameToken.IdentityV);
if (isPredefinedIdentityMap && !isChineseJapaneseOrKorean)
{
return(null, false);
}
if (!isChineseJapaneseOrKorean)
{
return(null, false);
}
var fullCmapName = cidFont.SystemInfo.ToString();
var nonUnicodeCMap = CMapCache.Get(fullCmapName);
if (nonUnicodeCMap == null)
{
return(null, true);
}
var unicodeCMapName = $"{nonUnicodeCMap.Info.Registry}-{nonUnicodeCMap.Info.Ordering}-UCS2";
return(CMapCache.Get(unicodeCMapName), true);
}