private static void KeepFonts(HashSet <string> fontsToKeep, Atom atomDA)
{
string da = Atom.GetText(atomDA);
ArrayAtom array = ArrayAtom.FromContentStream(ASCIIEncoding.ASCII.GetBytes(da));
var items = OpAtom.Find(array, new string[] { "Tf" });
foreach (var pair in items)
{
Atom[] args = OpAtom.GetParameters(array, pair.Item2);
Debug.Assert(args != null); // shouldn't really happen
if (args != null)
{
fontsToKeep.Add(Atom.GetName(args[0]));
}
}
}
public ArrayAtom GetTextOperator()
{
Debug.Assert(_text != null);
// get data and widths
byte[] section = new byte[_text.StreamLength];
Array.Copy(_data, _text.StreamOffset, section, 0, _text.StreamLength);
IDictionary <char, int> widths = _text.Font.Widths;
// convert to atoms
ArrayAtom textOp = ArrayAtom.FromContentStream(section);
string srcOp = ((OpAtom)textOp[1]).Text;
int numParams = srcOp == "\"" ? 4 : 2;
Debug.Assert(textOp.Count == numParams);
ArrayAtom srcParams = textOp[numParams == 4 ? 2 : 0] as ArrayAtom;
if (srcParams == null)
{
Debug.Assert(srcOp != "TJ");
srcParams = new ArrayAtom();
srcParams.Add(textOp[0]);
}
ArrayAtom dstParams = new ArrayAtom();
// copy items
int textSpanIndex = 0;
for (int i = 0; i < srcParams.Count; i++)
{
Atom item = srcParams[i];
if (item is StringAtom)
{
StringAtom str = (StringAtom)item;
Tuple <string, bool[]> redaction = null;
_redactions.TryGetValue(textSpanIndex++, out redaction);
if (redaction == null)
{
dstParams.Add(item.Clone());
}
else
{
string encoded = str.Text;
string whole = redaction.Item1;
bool[] redacted = redaction.Item2;
Debug.Assert((encoded.Length == whole.Length) || (encoded.Length == whole.Length * 2));
int bytesPerChar = encoded.Length / whole.Length;
int p1 = 0;
while (p1 < redacted.Length)
{
bool hidden = redacted[p1];
int width1000ths = 0;
int p2;
for (p2 = p1; p2 < redacted.Length; p2++)
{
if (hidden != redacted[p2])
{
break;
}
if (hidden)
{
width1000ths += widths[whole[p2]];
}
}
if (hidden)
{
dstParams.Add(new NumAtom(-width1000ths));
}
else
{
string sub1 = encoded.Substring(p1 * bytesPerChar, (p2 - p1) * bytesPerChar);
if (sub1.Length > 0)
{
dstParams.Add(new StringAtom(sub1));
}
}
p1 = p2;
}
}
}
else if (item is NumAtom)
{
NumAtom num = (NumAtom)item;
dstParams.Add(item.Clone());
}
else
{
Debug.Assert(false);
}
}
// make new operators
ArrayAtom newTextOp = new ArrayAtom();
if (srcOp == "\'")
{
newTextOp.Add(new OpAtom("T*"));
}
else if (srcOp == "\"")
{
newTextOp.Add(textOp[0].Clone());
newTextOp.Add(new OpAtom("Tw"));
newTextOp.Add(textOp[1].Clone());
newTextOp.Add(new OpAtom("Tc"));
newTextOp.Add(new OpAtom("T*"));
}
newTextOp.Add(dstParams);
newTextOp.Add(new OpAtom("TJ"));
return(newTextOp);
}