public CodeExpression GetExpression(InstructionForm frm, int argIdx, WriteOperation wrOp)
{
int curIdx = 0;
Token tok = toks[curIdx];
if (tok.Type != TokenType.Identifier)
throw new Exception("Expected an identifier!");
if (tok.Value == "ToString")
{
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.LParen)
throw new Exception("Expected an opening parenthesis!");
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Identifier)
throw new Exception("Expected an identifier for the expression to convert to a string!");
CodeExpression ldExpr = GetExpressionFromIdentifier(tok.Value, frm, argIdx, wrOp);
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.RParen)
throw new Exception("Expected the closing parenthesis!");
curIdx++;
return new CodeMethodInvokeExpression(
ldExpr,
"ToString"
);
}
else if (tok.Value == "DirectCast")
{
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.LParen)
throw new Exception("Expected an opening parenthesis!");
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Identifier)
throw new Exception("Expected an identifier representing the argument to cast!");
CustomInstructionArgParameter param;
if (!ParentArg.Parameters.TryGetValue(tok.Value, out param))
throw new Exception("Unknown parameter '" + tok.Value + "'!");
CodeExpression argLoadExpression = param.GetLoadExpression(frm, argIdx);
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Comma)
throw new Exception("Expected a comma before the destination type!");
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Identifier)
throw new Exception("Expected an identifier representing the type to cast to!");
CodeTypeReference destType;
switch(tok.Value.ToLower())
{
case "byte":
destType = StaticTypeReferences.Byte;
break;
case "sbyte":
destType = StaticTypeReferences.SByte;
break;
case "ushort":
destType = StaticTypeReferences.UShort;
break;
case "short":
destType = StaticTypeReferences.Short;
break;
case "uint":
destType = StaticTypeReferences.UInt;
break;
case "int":
destType = StaticTypeReferences.Int;
break;
case "ulong":
destType = StaticTypeReferences.ULong;
break;
case "long":
destType = StaticTypeReferences.Long;
break;
default:
destType = new CodeTypeReference(tok.Value);
break;
}
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.RParen)
throw new Exception("Expected closing parenthesis!");
curIdx++;
return new CodeCastExpression(
destType,
argLoadExpression
);
}
else
{
CodeExpression sourceExpression;
bool NamedArgNeedsCast = false;
if (tok.Value == "Stream")
{
sourceExpression = StaticTypeReferences.Emit_StreamArg;
}
else
{
if (tok.Value == "BitPatterns")
NamedArgNeedsCast = true;
sourceExpression = new CodeTypeReferenceExpression(tok.Value);
}
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Dot)
throw new Exception("Expected a dot!");
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Identifier)
throw new Exception("Expected an identifier!");
CodeMethodReferenceExpression methodRef = new CodeMethodReferenceExpression(
sourceExpression,
NamedArgNeedsCast ? BitPatternRegistry.GetPattern(tok.Value).Name : tok.Value
);
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.LParen)
throw new Exception("Expected an opening parenthesis!");
curIdx++;
List<CodeExpression> parms = new List<CodeExpression>(8);
tok = toks[curIdx];
bool expectsAnotherArg = true;
while (tok.Type != TokenType.RParen)
{
if (!expectsAnotherArg)
throw new Exception("Didn't expect another arg!");
switch (tok.Type)
{
case TokenType.Identifier:
parms.Add(GetExpressionFromIdentifier(tok.Value, frm, argIdx, wrOp, NamedArgNeedsCast));
break;
case TokenType.Number:
if (tok.NumberValue.Format == NumberFormat.Decimal)
{
parms.Add(new CodePrimitiveExpression((int)tok.NumberValue.Value));
}
else
{
parms.Add(new CodePrimitiveExpression(tok.NumberValue.Value));
}
break;
default:
throw new Exception("Unknown token type!");
}
curIdx++;
tok = toks[curIdx];
if (tok.Type != TokenType.Comma)
{
expectsAnotherArg = false;
}
else
{
curIdx++;
tok = toks[curIdx];
}
}
if (expectsAnotherArg)
throw new Exception("Expected another arg!");
return new CodeMethodInvokeExpression(
methodRef,
parms.ToArray()
);
}
}
private CodeExpression GetExpressionFromIdentifier(string val, InstructionForm frm, int argIdx, WriteOperation wrOp, bool namedParamNeedsCast = false)
{
CustomInstructionArgParameter param;
if (ParentArg.Parameters.TryGetValue(val, out param))
{
if (namedParamNeedsCast)
{
return frm[argIdx].ArgType.AsArgOperation.GetExpression(frm, argIdx, wrOp);
}
else
{
return param.GetLoadExpression(frm, argIdx);
}
}
else if (val == "Segment")
{
return new CodeFieldReferenceExpression(
new CodeThisReferenceExpression(),
frm.GetArgName(FieldTypeRegistry.Segment.ID, 1, InstructionArgSet.TotalArgs_Max)
);
}
else if (val == "ParentAssembler")
{
return StaticTypeReferences.ParentAssemblerExpression;
}
else if (val == "Stream")
{
return StaticTypeReferences.Emit_StreamArg;
}
else if (val.StartsWith("arg"))
{
int fArg = Utils.SingleDigitParse(val[3]) - 1;
return wrOp.WriteArguments[fArg].GetLoadExpression(frm);
}
else
{
return new CodeTypeReferenceExpression(val);
}
}
