private float ObjectToFloat(ParseObjectBase obj)
{
// Might be an integer if the value has no fractional part
if (obj is ParseInteger)
{
return((obj as ParseInteger).Value);
}
else if (obj is ParseReal)
{
return((obj as ParseReal).Value);
}
else
{
throw new ApplicationException($"Array does not contain numbers that can be converted to a rectangle.");
}
}
public ParseDictionary ParseTrailer()
{
Tokenizer.IgnoreComments = true;
TokenObject t = Tokenizer.GetToken();
ThrowOnError(t);
// Cross-reference table ends when we find a 'trailer' keyword instead of another section
if (!(t is TokenKeyword) || (((TokenKeyword)t).Value != ParseKeyword.Trailer))
{
throw new ApplicationException($"Trailer section must start with the 'trailer' keyword.");
}
ParseObjectBase obj = ParseObject();
if ((obj == null) || !(obj is ParseDictionary))
{
throw new ApplicationException($"Trailer section must contain a dictionary.");
}
return((ParseDictionary)obj);
}
public byte[] DecodeBytes(byte[] bytes)
{
if (HasFilter)
{
// Get the filtering as an array to be applied in order (if a single filter then convert from Name to an Array of one entry)
ParseObjectBase obj = Dictionary["Filter"];
ParseArray filters = obj as ParseArray;
if ((filters == null) && (obj is ParseName))
{
filters = new ParseArray(new List <ParseObjectBase>()
{
obj
});
}
foreach (ParseName filter in filters.Objects)
{
switch (filter.Value)
{
case "Fl":
case "FlateDecode":
bytes = FlateDecode(bytes);
break;
case "DCT":
case "DCTDecode":
break;
default:
throw new NotImplementedException($"Cannot process unrecognized stream filter '{filter.Value}'.");
}
}
}
return(bytes);
}
public ParseObjectBase ParseObject(bool allowEmpty = false)
{
Tokenizer.IgnoreComments = true;
TokenObject t = Tokenizer.GetToken();
if (allowEmpty && (t is TokenEmpty))
{
return(null);
}
else
{
ThrowOnEmptyOrError(t);
}
if (t is TokenName)
{
// Store one instance of each unique name to minimize memory footprint
TokenName tokenName = (TokenName)t;
return(ParseName.GetParse(tokenName.Value));
}
else if (t is TokenInteger)
{
TokenObject t2 = Tokenizer.GetToken();
ThrowOnError(t2);
// An object reference has a second integer, the generation number
if (t2 is TokenInteger)
{
TokenObject t3 = Tokenizer.GetToken();
ThrowOnError(t3);
// An object reference has a third value which is the 'R' keyword
if ((t3 is TokenKeyword) && (((TokenKeyword)t3).Value == ParseKeyword.R))
{
return(new ParseObjectReference(t as TokenInteger, t2 as TokenInteger));
}
Tokenizer.PushToken(t3);
}
Tokenizer.PushToken(t2);
return(new ParseInteger(t as TokenInteger));
}
else if (t is TokenReal)
{
return(new ParseReal(t as TokenReal));
}
else if (t is TokenStringHex)
{
return(new ParseString(t as TokenStringHex));
}
else if (t is TokenStringLiteral)
{
return(new ParseString(t as TokenStringLiteral));
}
else if (t is TokenArrayOpen)
{
List <ParseObjectBase> objects = new List <ParseObjectBase>();
ParseObjectBase entry = null;
while (true)
{
entry = ParseObject();
if (entry == null)
{
break;
}
else
{
ThrowOnEmptyOrError(t);
}
objects.Add(entry);
}
ThrowIfNot <TokenArrayClose>(Tokenizer.GetToken());
return(new ParseArray(objects));
}
else if (t is TokenDictionaryOpen)
{
List <string> names = new List <string>();
List <ParseObjectBase> entries = new List <ParseObjectBase>();
ParseObjectBase value1 = null;
ParseObjectBase value2 = null;
while (true)
{
value1 = ParseObject();
if (value1 == null)
{
break;
}
else
{
ThrowOnEmptyOrError(t);
}
// Key value must be a Name
ParseName name = value1 as ParseName;
if (name == null)
{
throw new ApplicationException($"Dictionary key must be a name instead of {name.GetType().Name}.");
}
value2 = ParseObject();
if (value2 == null)
{
throw new ApplicationException($"Dictionary value missing for key {name.Value}.");
}
else
{
ThrowOnEmptyOrError(t);
}
names.Add(name.Value);
entries.Add(value2);
}
ThrowIfNot <TokenDictionaryClose>(Tokenizer.GetToken());
return(new ParseDictionary(names, entries));
}
else if (t is TokenKeyword)
{
switch ((t as TokenKeyword).Value)
{
case ParseKeyword.True:
return(ParseObjectBase.True);
case ParseKeyword.False:
return(ParseObjectBase.False);
case ParseKeyword.Null:
return(ParseObjectBase.Null);
}
}
else if (t is TokenIdentifier)
{
// Store one instance of each unique identifier to minimize memory footprint
TokenIdentifier tokenIdentifier = (TokenIdentifier)t;
return(ParseIdentifier.GetParse(tokenIdentifier.Value));
}
// Token is not one that starts an object, so put the token back
Tokenizer.PushToken(t);
return(null);
}
public ParseIndirectObject ParseIndirectObject()
{
Tokenizer.IgnoreComments = true;
TokenObject t = Tokenizer.GetToken();
ThrowOnEmptyOrError(t);
// Indirect object starts with an integer, the object identifier
if (!(t is TokenInteger))
{
Tokenizer.PushToken(t);
return(null);
}
// Second is another integer, the generation number
TokenObject u = Tokenizer.GetToken();
ThrowOnEmptyOrError(u);
if (!(u is TokenInteger))
{
Tokenizer.PushToken(t);
Tokenizer.PushToken(u);
return(null);
}
// This is the keyword 'obj'
TokenObject v = Tokenizer.GetToken();
ThrowOnEmptyOrError(v);
if (!(v is TokenKeyword) || ((v as TokenKeyword).Value != ParseKeyword.Obj))
{
Tokenizer.PushToken(t);
Tokenizer.PushToken(u);
Tokenizer.PushToken(v);
return(null);
}
// Get actual object that is the content
ParseObjectBase obj = ParseObject();
if (obj == null)
{
throw new ApplicationException($"Indirect object has missing content.");
}
// Must be followed by either 'endobj' or 'stream'
v = Tokenizer.GetToken();
ThrowOnEmptyOrError(v);
TokenKeyword keyword = v as TokenKeyword;
if (keyword == null)
{
// PH: FIXME:
//throw new ApplicationException($"Indirect object has missing 'endobj or 'stream'.");
return(new ParseIndirectObject(t as TokenInteger, u as TokenInteger, new ParseInteger(0)));
}
if (keyword.Value == ParseKeyword.EndObj)
{
return(new ParseIndirectObject(t as TokenInteger, u as TokenInteger, obj));
}
else if (keyword.Value == ParseKeyword.Stream)
{
ParseDictionary dictionary = obj as ParseDictionary;
if (dictionary == null)
{
throw new ApplicationException($"Stream must be preceded by a dictionary.");
}
if (!dictionary.ContainsName("Length"))
{
throw new ApplicationException($"Stream dictionary must contain a 'Length' entry.");
}
ParseObjectBase lengthObj = dictionary["Length"];
// Resolve any object reference
ParseObjectReference reference = lengthObj as ParseObjectReference;
if (reference != null)
{
lengthObj = OnResolveReference(reference);
}
ParseInteger length = lengthObj as ParseInteger;
if (length == null)
{
throw new ApplicationException($"Stream dictionary has a 'Length' entry that is not an integer entry.");
}
if (length.Value < 0)
{
throw new ApplicationException($"Stream dictionary has a 'Length' less than 0.");
}
byte[] bytes = Tokenizer.GetBytes(length.Value);
if (bytes == null)
{
throw new ApplicationException($"Cannot read in expected {length.Value} bytes from stream.");
}
// Stream contents must be followed by 'endstream'
v = Tokenizer.GetToken();
ThrowOnEmptyOrError(v);
keyword = v as TokenKeyword;
if (keyword == null)
{
throw new ApplicationException($"Stream has missing 'endstream' after content.");
}
if (keyword.Value != ParseKeyword.EndStream)
{
throw new ApplicationException($"Stream has unexpected keyword {keyword.Value} instead of 'endstream'.");
}
// Stream contents must be followed by 'endobj'
v = Tokenizer.GetToken();
ThrowOnEmptyOrError(v);
keyword = v as TokenKeyword;
if (keyword == null)
{
throw new ApplicationException($"Indirect object has missing 'endobj'.");
}
if (keyword.Value != ParseKeyword.EndObj)
{
throw new ApplicationException($"Indirect object has unexpected keyword {keyword.Value} instead of 'endobj'.");
}
return(new ParseIndirectObject(t as TokenInteger, u as TokenInteger, new ParseStream(dictionary, bytes)));
}
else
{
throw new ApplicationException($"Indirect object has unexpected keyword {keyword.Value}.");
}
}
public ParseIndirectObject(TokenInteger id, TokenInteger gen, ParseObjectBase obj)
{
Id = id.Value;
Gen = gen.Value;
Object = obj;
}
public PdfObject(PdfObject parent, ParseObjectBase parse)
{
Parent = parent;
ParseObject = parse;
}
