public ForMachineState GetNext(Token token)
{
ForMachineState nextState = this.CurrentState;
ForStateTransition transition = new ForStateTransition(CurrentState, token.Type);
if (this.CurrentState == ForMachineState.EQUALS && token.Type == TokenType.TO)
{
this.exp.Reset(); //valor inicial a ser atribuido na variavel esta em r0
this.command.ReceivedLoopedVariable(this.loopedVariable);
}
else if (this.CurrentState == ForMachineState.TO && token.Type == TokenType.STEP)
{
this.exp.Reset(); //valor maximo para parada do loop esta em r0
this.command.SaveMaxValueForLoop(this.loopedVariable);
}
else if (this.CurrentState == ForMachineState.STEP && token.Type == TokenType.END)
{
this.exp.Reset(); //valor de passo do loop esta em r0
this.command.SaveStepValueForLoop(this.loopedVariable);
}
if ((this.CurrentState == ForMachineState.EQUALS && token.Type != TokenType.TO) ||
(this.CurrentState == ForMachineState.TO && token.Type != TokenType.STEP) ||
(this.CurrentState == ForMachineState.STEP && token.Type != TokenType.END))
{
this.exp.MoveToNextState(token);
}
else if (!transitions.TryGetValue(transition, out nextState))
{
throw new Exception("For: Invalid transition: " + CurrentState + " -> " + nextState + "\n" + token.Text + " " + token.Type);
}
if (this.CurrentState == ForMachineState.FOR && (token.Type == TokenType.VAR || token.Type == TokenType.ARRAY))
{
this.loopedVariable = token;
}
Console.WriteLine("FOR: " + this.CurrentState + " -> " + nextState + ": " + token.Text);
return(nextState);
}
public ForStateMachine(VariableTable variables, FileManager fileManager)
{
CurrentState = ForMachineState.START;
transitions = new Dictionary <ForStateTransition, ForMachineState>
{
{ new ForStateTransition(ForMachineState.START, TokenType.END), ForMachineState.START },
{ new ForStateTransition(ForMachineState.START, TokenType.FOR), ForMachineState.FOR },
// guarda variavel a ser loopada
{ new ForStateTransition(ForMachineState.FOR, TokenType.VAR), ForMachineState.VAR },
{ new ForStateTransition(ForMachineState.FOR, TokenType.ARRAY), ForMachineState.VAR },
// recebe token que indica a atribuicao do valor a seguir a variavel recebida
{ new ForStateTransition(ForMachineState.VAR, TokenType.EQUALS), ForMachineState.EQUALS },
// calcula valor da expressao a ser usada como valor inicial -> atribui a variavel a ser loopada armazenada anteriormente (guarda na memoria)
{ new ForStateTransition(ForMachineState.EQUALS, TokenType.TO), ForMachineState.TO },
// calcula valor da expressao a ser usada como valor final -> guarda na memoria esse valor para futuras comparacoes
{ new ForStateTransition(ForMachineState.TO, TokenType.STEP), ForMachineState.STEP },
// calcula valor da expressao a ser usada como passo -> guarda na memoria esse valor para futuro uso na hora de executar o passo
{ new ForStateTransition(ForMachineState.STEP, TokenType.END), ForMachineState.START },
};
this.variables = variables;
this.command = new ForCommand(variables, fileManager);
this.exp = new ArithmeticStateMachine(variables, fileManager);
}
public void MoveToNextState(Token token)
{
ForMachineState nextState = GetNext(token);
this.CurrentState = nextState;
}
public ForStateTransition(ForMachineState currentState, TokenType token)
{
this.CurrentState = currentState;
this.Token = token;
}
