public static ConditionalExpression Parse(ref string[] program)
{
ConditionalExpression ret = null;
Expression expr = null;
string token1 = ParseUtils.PeekToken(program);
TokenType type1 = WooScript.GetTokenType(token1);
if (token1.Equals("(", StringComparison.Ordinal))
{
ret = new ConditionalBrackets();
(ret as ConditionalBrackets).Parse(ref program);
}
else if (type1 == TokenType.UnaryBooleanOp)
{
ret = WooScript.GetUnaryBooleanOp(token1);
(ret as UnaryBooleanOp).Parse(ref program);
}
else if (type1 == TokenType.floatVar ||
type1 == TokenType.floatNum ||
type1 == TokenType.floatFunction)
{
expr = ExpressionBuilder.Parse(ref program);
}
else
{
throw new ParseException("Unrecognised expression \"" + token1 + "\"");
}
string token2 = ParseUtils.GetToken(ref program);
TokenType type2 = WooScript.GetTokenType(token2);
if (type2 == TokenType.ConditionalOp)
{
if (type1 != TokenType.floatNum && type1 != TokenType.floatVar && type1 != TokenType.floatFunction)
{
throw new ParseException("Conditional operation only takes floating point parameters");
}
ConditionalOp condOp = WooScript.GetConditionalOp(token2);
condOp._Arg1 = expr;
Expression arg2 = ExpressionBuilder.Parse(ref program);
if (arg2.GetExpressionType() != VarType.varFloat)
{
throw new ParseException("Conditional operation only takes floating point parameters");
}
condOp._Arg2 = arg2;
// no need for precedence check on conditional operator
ret = condOp;
string token3 = ParseUtils.PeekToken(program);
TokenType type3 = WooScript.GetTokenType(token3);
if (type3 == TokenType.BooleanOp)
{
BooleanOp boolOp = WooScript.GetBooleanOp(token3);
boolOp._Arg1 = condOp;
ConditionalExpression condArg2 = ConditionBuilder.Parse(ref program);
boolOp._Arg2 = condArg2;
// operator precedence check
if (condArg2 is BooleanOp)
{
if ((condArg2 as BooleanOp).GetPrecedence() < boolOp.GetPrecedence())
{
// shuffle args
boolOp._Arg2 = (condArg2 as BooleanOp)._Arg1;
(condArg2 as BooleanOp)._Arg1 = boolOp;
boolOp = (condArg2 as BooleanOp);
}
}
ret = boolOp;
}
}
if (ret == null)
{
throw new ParseException("Malformed conditional expression, expected conditional operation");
}
return(ret);
}