private static CalculateExpression Parse(Dictionary <string, MoneyColumnMetadataJsModel> columns, MoneyColumnMetadataJsModel column, string function)
{
CalculateExpression currentExpression = new EmptyExpression(column);
try
{
while (function.Length > 0)
{
function = function.Trim();
if (function[0] == '[')
{
var referenceName = function.Substring(1, function.IndexOf(']') - 1);
function = function.Remove(0, function.IndexOf(']') + 1);
var matchingColumn = columns[referenceName];
currentExpression = currentExpression.TryApply(new ReferenceExpression(matchingColumn));
}
else if (function[0] == '(')
{
var counter = 1;
int i;
for (i = 1; i < function.Length && counter > 0; i++)
{
if (function[i] == '(')
{
counter++;
}
if (function[i] == ')')
{
counter--;
}
}
var sub = function.Substring(0, i);
var subExp = Parse(columns, column, sub.TrimStart('(').TrimEnd(')'));
currentExpression = currentExpression.TryApply(new ParenthesisExpression(subExp));
function = function.Substring(i);
}
else if (function[0] == '{')
{
var constant = function.Substring(1, function.IndexOf('}') - 1);
function = function.Remove(0, function.IndexOf('}') + 1);
currentExpression = currentExpression.TryApply(new ConstantExpression(column, constant));
}
else
{
var symbol = BinaryExpression.Symbols.FirstOrDefault(function.StartsWith);
if (symbol != null)
{
currentExpression = new BinaryExpression(column, symbol).TryApply(currentExpression);
function = function.Substring(symbol.Length);
}
else
{
return(new FailedToParseExpression(column, function));
}
}
}
}
catch
{
return(new FailedToParseExpression(column, function));
}
return(currentExpression);
}