public override BaseNode GetNextNode(Executer exec, BaseNode alreadyUsedChildNode, object nodesResult)
{
//Hmm, could I execute the if-statement directly here? Must I really wait
//for executer to execute it and then proceed based on the result??
//I'll go for direct if-clause execution for now:
if (alreadyUsedChildNode == null)
{
// if (this.m_ifExpression==null || Convert.ToInt32(this.m_ifExpression.Evaluate(exec)) != 0)
if (this.m_ifExpression==null ||
Convert.ToInt32(this.m_ifExpression.Evaluate(exec).GetUnboxed(exec)) != 0)
return (BaseNode)this.FirstChild;
if (this.m_nextIfNode!=null)
return this.m_nextIfNode;
return null;
}
return base.GetNextNode(exec, alreadyUsedChildNode, nodesResult);
// int nIndex = this.ChildNodes.IndexOfValue(alreadyUsedChildNode);
// if (nIndex == 0) //it was the "if" clause
// {
// if ((int)((Types.Object)nodesResult).GetUnboxed() != 0)
// return (BaseNode)this.ChildNodes.GetByIndex(2); //this is where the statements begin if it's true
// if (this.ChildNodes.Count > 1)
// return (BaseNode)this.ChildNodes.GetByIndex(1);
// }
// return null;
}
public virtual BaseNode GetNextNode(Executer exec, BaseNode alreadyUsedChildNode, object nodesResult)
{
if (alreadyUsedChildNode != null)
return (BaseNode)alreadyUsedChildNode.NextSibling;
if (this.HasChildNodes)
return (BaseNode)this.FirstChild;
return null;
}
public void Rewind()
{
//EH.Put("Rewind called");
MethodNode nodeToExecute = null;
if (this.m_callStack != null)
{
//find first item in stack (i.e., the first called method)
while (this.m_callStack.Count > 1)
this.m_callStack.Pop();
nodeToExecute = (MethodNode)this.m_callStack.Pop();
}
this.m_callStack = new System.Collections.Stack();
this.m_valueStack = new System.Collections.ArrayList();
this.m_currentNode = null;
if (nodeToExecute != null)
this.m_callStack.Push(nodeToExecute);
}
private static bool HandleNodeBorderChars(string sDividerChar, ref BaseNode currentNode)
{
if (sDividerChar == "{" || sDividerChar == "}")
{
if (sDividerChar == "{")
{
bool bCreateNewUndefinedNode = true;
//if there's a { in the middle of the code, with nothing special preceding it, (if,for etc)
//let's just create a chunkNode for it.
// if (currentNode.GetType() == typeof(MethodNode))
// //Metho
// bCreateNewUndefinedNode = false;
// else
// {
try
{
//if we're in a chunk node which is supposed to close automatically after one line, like:
// if(true) x=1;
//and instead we encounter a {, like:
// if(true) {
//that means it should NOT close automatically.
ChunkNode chunkNode = (ChunkNode)currentNode;
if (chunkNode.CloseNodeAfterNextLine)
{
chunkNode.CloseNodeAfterNextLine = false;
bCreateNewUndefinedNode = false;
}
}
catch
{}
// }
if (bCreateNewUndefinedNode)
{
ChunkNode newChunkNode = new ChunkNode();
currentNode.AppendChild("undef", newChunkNode);
currentNode = newChunkNode;
}
}
else // "}"
currentNode = (BaseNode)currentNode.ParentNode;
return true;
}
return false;
}
public static ClassNode Parse(string sScript)
{
ArrayList aAllLines = new ArrayList();
string[] aKeywords = new string[]{"for", "else if", "if", "else", "while", "goto", "gosub", "return"};
//TODO: I don't handle keyword and a statement on the same line right now-
//e.g. "if (true) blabla();" or "for (;;) put(1);"
BaseNode rootNode = new BaseNode();
ClassNode classNode = new ClassNode();
rootNode.AppendChild("Class_01", classNode);
BaseNode currentNode = classNode;
//easier parsing if \r\n is replaced by \n
sScript = sScript.Replace("\r\n", "\n");
//also a little easier if script always ends with a \n
if (!sScript.EndsWith("\n"))
sScript+="\n";
//structure will be [ScriptName:[MethodName:[LabelName:[clause:[clause]]]]]
//Labels must be on top level in a method (e.g. not inside an if(){} clause)
while (sScript.Length > 0)
{
//first divide into "lines" - EndOfLine represented by: return ; { or }
string sLine = "";
string sDividerChar = "";
MatchCollection matches = Regex.Matches(sScript, "[^{};\\n]*[{};\\n]");
foreach (Match m in matches)
{
sLine = sScript.Substring(0, m.Index+m.Length);
sDividerChar = m.Value.Substring(m.Value.Length-1,1);
if (sDividerChar == ";")
{
//must check if the ";" is inside parenthesis - if so, it doesn't count (e.g. "for(;;)")
//only when the number of "(" is the same as the number of ")", the ";" is outside
string sCheck = sLine.Replace("(", "");
int nNumRight = sLine.Length-sCheck.Length;
sCheck = sLine.Replace(")", "");
int nNumLeft = sLine.Length-sCheck.Length;
if (nNumRight != nNumLeft)
continue;
}
sScript = sScript.Remove(0, sLine.Length);
sLine = sLine.Remove(sLine.Length-1,1);
break;
}
sLine = sLine.Trim();
//handle if the line only consists of a { or }
if (sLine.Length == 0)
{
if (HandleNodeBorderChars(sDividerChar, ref currentNode))
continue;
}
//empty and remmed lines are ignored:
if (sLine.Length == 0 || sLine.IndexOf("//") == 0)
{
continue;
}
if (currentNode.GetType() == typeof(ClassNode)) //.Depth == 1) //class level, i.e. where methods are defined
{
//search for "on method([args])"
Match m = Regex.Match(sLine, "on\\s*\\w*\\s*[(][^()]*[)]");
if (m.Success)
{
string sMethod = m.Value.Replace("on ", "").Trim();
string sArgs = sMethod.Remove(0,sMethod.IndexOf("("));
sMethod = sMethod.Substring(0,sMethod.IndexOf("("));
MethodNode methodNode = new MethodNode();
methodNode.DefineArguments(sArgs.Substring(1,sArgs.Length-2));
currentNode.AppendChild(sMethod, methodNode);
currentNode = methodNode;
continue;
}
}
//separate code flow keywords/tokens from expressions
if (sLine.IndexOf(":") == sLine.Length-1)
{
//it's a label. Labels can currently only occur on Method level
if (currentNode.GetType() != typeof(MethodNode))
throw new Exception("Labels must be defined in Method scope!");
//TODO: Labels can't be nodes - they're not defined with {}'s... More like an HTML anchor
//sLine.Substring(0,sLine.Length-2)
}
#region Check for keywords
foreach (string sKeyword in aKeywords)
{
//[^\\w]+*[( ]*
Match m = Regex.Match(sLine+" ", sKeyword+"[^\\w]+[( ]*"); //"\\s*[(]*");
if (m.Success)
{
ChunkNode newNode = null;
string sArgs = GetStringWithinParenthesis(sLine);
switch (sKeyword)
{
case "for":
ForNode forNode = new ForNode();
forNode.SetConditions(sArgs);
newNode = forNode;
//With the current line seek method, the ";" in for(;;) forces us to look ahead in script
//TODO: lookahead for(;;)
break;
case "if":
if (sArgs == null)
throw new Exception("If statement incomplete");
IfNode ifNode = new IfNode();
ifNode.SetIfStatement(sArgs);
newNode = ifNode;
break;
case "else if":
case "else":
//is the current node an IfNode?
if (currentNode.GetType() != typeof(IfNode))
throw new Exception("\""+sKeyword+"\" must come after an \"if\" statement");
IfNode elseifNode = new IfNode();
if (sKeyword == "else if")
{
//TODO: don't understand C# scopes... Why can't I define sArgs here too? Can't see any risk for confusion or mistakes!?
//And sometimes it's too slack:
//a member variable can have the same name as a variable in a method with no complaits,
//although that is clearly a mistake in most cases?
if (sArgs == null)
throw new Exception("Else if statement incomplete");
elseifNode.SetIfStatement(sArgs);
}
IfNode oldIfNode = (IfNode)currentNode;
oldIfNode.SetNextIfNode(elseifNode);
newNode = elseifNode;
break;
}
if (newNode!=null)
{
newNode.CloseNodeAfterNextLine = true;
currentNode.AppendChild(sKeyword, newNode);
currentNode = newNode;
}
break;
}
}
#endregion
if (HandleNodeBorderChars(sDividerChar, ref currentNode))
continue;
string sStatement = sLine;
ExpressionNode expNode = new ExpressionNode();
expNode.SetExpression(sStatement);
currentNode.AppendChild(sStatement, expNode);
//TODO: how to check nicely if ChunkNode is one of the base classes of currentNode?? This is ugly (?):
try
{
ChunkNode chunkNode = (ChunkNode)currentNode;
if (chunkNode.CloseNodeAfterNextLine)
currentNode = (BaseNode)currentNode.ParentNode;
}
catch
{}
}
// System.Xml.XmlDocument doc = new System.Xml.XmlDocument();
// rootNode.AddToXml(doc);
// doc.Save("Testing.xml");
return classNode;
}
//returns false when finished
public bool Step()
{
bool bDebug = false;
BaseNode owningNode = (BaseNode)this.m_callStack.Peek();
BaseNode nextNode = owningNode.GetNextNode(this, this.m_currentNode, null);
if (nextNode == null)
{
if (bDebug) EH.Put("No more nodes on that depth");
//that node is finished. Go up one level or quit!
if (this.m_callStack.Count <= 1) //there has to be two nodes above the current!
{
//fire event! Quit!
return false;
}
//step up one level, and find next node there:
this.m_currentNode = (BaseNode)this.m_callStack.Pop();
this.Step();
}
else
{
if (nextNode.ParentNode != owningNode) //when going down one level (always just one)
{
this.m_callStack.Push(nextNode.ParentNode);
this.m_currentNode = nextNode;
if (bDebug) EH.Put("Entering childnode: "+nextNode.Name);
}
else //new node is at same level
{
this.m_currentNode = nextNode;
if (bDebug) EH.Put("Nextsibling : "+nextNode.Name); //nextNode.GetType().ToString()
}
}
// if (this.m_currentNode.GetType() == typeof(IfNode))
// this.m_currentNode = this.m_currentNode;
//only ExpressionNodes can be executed, the others are only asked for next node.
if (this.m_currentNode.GetType() != typeof(ExpressionNode))
{
this.m_callStack.Push(this.m_currentNode);
this.m_currentNode = null;
return this.Step();
}
else
{
this.m_currentNode.Execute(this); //object oVal =
return true;
}
}