//returns a node that is nested somewhere inside this node, the path to the nested node
//is described by a series of node names giben in 'keys'
public TextEngineNode getNestedNodeByKey(String[] keys)
{
TextEngineNode tempNode = this;
foreach (string key in keys)
{
if (tempNode == null)
{
return(null);
}
else
{
tempNode = tempNode.getNodeByKey(key);
}
}
return(tempNode);
}
private TextEngineNode parseEngineData(ByteArray bytes, uint depth)
{
//set up the root node that is the top of the tree
TextEngineNode rootNode = new TextEngineNode();
rootNode.type = TextEngineNode.TYPE_STRUCTURE;
rootNode.key = "root";
long tempPos = bytes.Position;
while (bytes.Position < bytes.Length)
{
//find a key
String key = findKeyOrEnd(bytes); //returns null if end of structure is found
if (key == null)
{
return(rootNode);
}
//if we have reached this point we have found a key of the form "/keyname "
//what follows is either a value or a structure, the following code works out which it is
Boolean isStructure = false;
byte b = bytes.getByte();
//depending on the value of the next byte, we know what is going to follow
switch (b)
{
case 0x20: //if there is a space, then a value follows
//little hack to get structures inside of arrays working
if (bytes.bytes[bytes.Position] == 0x5b && bytes.bytes[bytes.Position + 1] == 0x0a)
{
Boolean stopBracketLoop = false;
while (!stopBracketLoop)
{
TextEngineNode node2 = parseEngineData(bytes, depth + 1);
node2.key = key;
rootNode.structure.Add(node2);
if (bytes.Position == bytes.Length)
{
return(rootNode); //massive hack just to get it working,
//basically it just ends if we run out of data
}
while (bytes.Position < bytes.Length)
{
b = bytes.getByte();
if (b != 0x09 && b != 0x3e && b != 0x0a) //its a tab, so we can skip
{
if (b == 0x5d)
{
stopBracketLoop = true;
}
else if (b == 0x3c || b == 0x2f)
{
//we have a new structure or property
}
else
{
if (bytes.Position == bytes.Length)
{
return(rootNode); //massive hack just to get it working,
//basically it just ends if we run out of data
}
Console.Out.WriteLine("unknown byte in middle of array at: " + bytes.Position);
}
break;
}
}
}
continue;
}
else
{
isStructure = false;
}
break;
case 0x0a: //if its a new line, then we have found a structure
isStructure = true;
break;
default:
Console.Out.WriteLine("unknown value after key: 0x" + b + ", at: " + bytes.Position);
break;
}
//now we can build the node
TextEngineNode node;
if (isStructure)
{
//if its a structure, we use recursion to build the node
node = parseEngineData(bytes, depth + 1);
node.key = key;
}
else
{
//if its a value, we create a new node and fill in the value manually
node = new TextEngineNode();
node.key = key;
node.value = findValue(bytes);
node.type = TextEngineNode.TYPE_VALUE;
}
rootNode.structure.Add(node);
}
return(rootNode);
}
//the text engine data format is complicated, although godden told me its the
//same as how pdf's store it
private void parseEngineDataStructure(ByteArray bytes, long endOfTag)
{
byte b;
//find the start of the data by looking for the first <
while ((b = bytes.getByte()) != 0x3c && bytes.Position < endOfTag)
{
}
//make sure we actually found one
if (bytes.Position == endOfTag)
{
throw new Exception("could not find start of text engine data");
}
long startPos = bytes.Position;
//we are at the start now, the end of the data will be 0x3e 0x3e 0x00
byte firstByte = bytes.getByte();
byte secondByte = bytes.getByte();
byte thirdByte = bytes.getByte();
//move to the start of the structure
while (bytes.Position < endOfTag)
{
// 0x3e is a >
if (firstByte == 0x3e && secondByte == 0x3e && thirdByte == 0x00)
{
break;
}
firstByte = secondByte;
secondByte = thirdByte;
thirdByte = bytes.getByte();
}
if (bytes.Position == endOfTag)
{
throw new Exception("could not find end of text engine data");
}
long endPos = bytes.Position;
//we can use the startPos and endPos to get the data in the middle
bytes.Position = startPos;
ByteArray engineData = bytes.getBytes((uint)(endPos - startPos));
//engineData now contains the engineData, this code works
TextEngineNode dataObject = parseEngineData(engineData, 0);
//now that we have parsed all of the engineData and stored it in 'dataObject', we retreive the
//nodes that we need
TextEngineNode tempNode;
tempNode = dataObject.getNestedNodeByKey(new string[] { "ResourceDict", "FontSet", "Name" });
if (tempNode != null)
{
fontName = tempNode.value;
}
tempNode = dataObject.getNestedNodeByKey(new string[] { "EngineDict", "StyleRun", "RunArray",
"StyleSheet", "StyleSheetData", "FontSize" });
if (tempNode != null)
{
fontSize = tempNode.value;
}
tempNode = dataObject.getNestedNodeByKey(new string[] { "EngineDict", "Editor", "Text" });
if (tempNode != null)
{
text = tempNode.value;
}
}
