Exemple #1
0
        public Statement DecompileConditionalJump(bool isOpt = false) // TODO: guess for loop, probably requires a large restructure
        {
            PopByte();
            var       scopeStartOffset = StartPositions.Pop();
            Statement statement        = null;
            bool      hasElse          = false;
            var       scopeStatements  = new List <Statement>();

            UInt16     scopeEndJmpOffset = 0;
            UInt16     afterScopeOffset  = 0;
            Expression conditional       = null;

            if (isOpt)
            {
                var obj      = ReadObject();
                var optCheck = Convert.ToBoolean(ReadByte());
                afterScopeOffset = ReadUInt16();

                String special = (optCheck ? "" : "!") + obj.ObjectName;
                conditional = new SymbolReference(null, null, null, special);
            }
            else
            {
                afterScopeOffset = ReadUInt16();
                conditional      = DecompileExpression();
            }

            if (conditional == null)
            {
                return(null);
            }

            if (afterScopeOffset < scopeStartOffset) // end of do_until detection
            {
                scopeStartOffset = afterScopeOffset;
                var outerScope     = Scopes[CurrentScope.Peek()];
                var startStatement = StatementLocations[afterScopeOffset];
                StatementLocations.Remove(afterScopeOffset);
                var index = outerScope.IndexOf(startStatement);
                scopeStatements = new List <Statement>(outerScope.Skip(index));
                outerScope.RemoveRange(index, outerScope.Count - index);
                statement = new DoUntilLoop(conditional, new CodeBody(scopeStatements, null, null), null, null);
            }

            Scopes.Add(scopeStatements);
            CurrentScope.Push(Scopes.Count - 1);
            while (Position < afterScopeOffset)
            {
                if (CurrentIs(StandardByteCodes.Jump))
                {
                    var contPos = (UInt16)Position;
                    PopByte();
                    scopeEndJmpOffset = ReadUInt16();
                    if (scopeEndJmpOffset == scopeStartOffset)
                    {
                        statement = new WhileLoop(conditional, new CodeBody(scopeStatements, null, null), null, null);
                        break;
                    }
                    else if (Position < afterScopeOffset) // if we are not at the end of the scope, this is a continue statement in a loop rather than an else statement
                    {
                        var cont = new ContinueStatement(null, null);
                        StatementLocations.Add(contPos, cont);
                        scopeStatements.Add(cont);
                    }
                    else if (ForEachScopes.Count != 0 && scopeEndJmpOffset == ForEachScopes.Peek())
                    {
                        var breakStatement = new BreakStatement(null, null);
                        StatementLocations.Add(contPos, breakStatement);
                        scopeStatements.Add(breakStatement);
                    }
                    else
                    {
                        hasElse = true;
                    }

                    continue;
                }

                var current = DecompileStatement();
                if (current == null)
                {
                    return(null); // ERROR ?
                }
                scopeStatements.Add(current);
            }
            CurrentScope.Pop();


            List <Statement> elseStatements = new List <Statement>();

            if (hasElse)
            {
                var endElseOffset = scopeEndJmpOffset;
                Scopes.Add(elseStatements);
                CurrentScope.Push(Scopes.Count - 1);
                while (Position < endElseOffset)
                {
                    var current = DecompileStatement();
                    if (current == null)
                    {
                        return(null); // ERROR ?
                    }
                    elseStatements.Add(current);
                }
                CurrentScope.Pop();
            }

            statement = statement ?? new IfStatement(conditional, new CodeBody(scopeStatements, null, null),
                                                     null, null, elseStatements.Count != 0 ? new CodeBody(elseStatements, null, null) : null);
            StatementLocations.Add(scopeStartOffset, statement);
            return(statement);
        }