/// <summary>
/// Here is where each cell that's changed essentially has a delegate that notifies its respective event has changed.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
public void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (e.PropertyName == "Text")
{
BasicCell temporary = sender as BasicCell;
string cellname = temporary.GetCellName();
DeleteDependency(cellname);
if (temporary.Text != "" && temporary.Text[0] == '=' && temporary.Text.Length > 1)
{
ExpressionTree tree = new ExpressionTree(temporary.Text.Substring(1));
SetDependency(cellname, tree.GetVariables());
}
EvaluateCell(sender as Cell);
}
else if (e.PropertyName == "BGColor")
{
CellPropertyChanged(sender, new PropertyChangedEventArgs("BGColor"));
}
}
/// <summary>
/// Function used to evaluate all the cells.
/// LOGIC LIVES HERE COULDN'T ENCAPSULATE FURTHER
/// </summary>
/// <param name="cell"></param>
private void EvaluateCell(Cell cell)
{
BasicCell evalCell = cell as BasicCell;
bool error = false;
if (string.IsNullOrWhiteSpace(evalCell.Text))
{
evalCell.setValue("");
CellPropertyChanged(cell, new PropertyChangedEventArgs("Value"));
}
else if (evalCell.Text.Length > 1 && evalCell.Text[0] == '=')
{
string text = evalCell.Text.Substring(1);
ExpressionTree evalTree = new ExpressionTree(text);
string[] variables = evalTree.GetVariables();
foreach (string variableName in variables)
{
if (GetCell(variableName) == null)
{
CellPropertyChanged(cell, new PropertyChangedEventArgs("Value"));
error = true;
break;
}
Cell variableCell = GetCell(variableName);
double variableValue;
if (string.IsNullOrEmpty(variableCell.Value))
{
evalTree.SetVariable(variableName, 0);
}
else if (!double.TryParse(variableCell.Value, out variableValue))
{
evalTree.SetVariable(variableName, 0);
}
else
{
evalTree.SetVariable(variableName, variableValue);
}
string cellToEval = evalCell.ColumnIndex.ToString() + evalCell.RowIndex.ToString();
if (variableName == cellToEval)
{
evalCell.setValue("!(Self Reference)");
CellPropertyChanged(cell, new PropertyChangedEventArgs("Value"));
error = true;
break;
}
}
if (error)
{
return;
}
foreach (string variableName in variables)
{
if (IsCircularReference(variableName, evalCell.GetCellName()))
{
evalCell.setValue("!(Circular Reference!)");
CellPropertyChanged(cell, new PropertyChangedEventArgs("Value"));
error = true;
break;
}
}
if (error)
{
return;
}
evalCell.setValue(evalTree.Evaluate().ToString());
CellPropertyChanged(cell, new PropertyChangedEventArgs("Value"));
}
else
{
evalCell.setValue(evalCell.Text);
CellPropertyChanged(cell, new PropertyChangedEventArgs("Value"));
}
string cellName = evalCell.GetCellName();
if (dependencyDict.ContainsKey(cellName))
{
foreach (string dependentCell in dependencyDict[cellName])
{
EvaluateCell(GetCell(dependentCell));
}
}
}