private static void getNote(Tokenizer t, Diagram d)
{
// a NOTE takes the form: NOTE Actor: the note is here....
Token id = t.NextToken();
if (id.type != TokenType.TOK_IDENTIFIER) { d.HasErrors = true; return; }
var actor = d.MaybeNewActor(id.data);
Token str = t.NextToken();
string desc = null;
switch(str.type) {
case TokenType.TOK_STRING:
desc = str.data;
break;
case TokenType.TOK_EOL:
desc = "";
break;
default:
d.HasErrors = true;
return;
}
var ln = d.AddLine(actor, actor);
ln.Desc = desc;
ln.Note = true;
}
public static Diagram Parse(Tokenizer t)
{
var ans = new Diagram();
while( !(ans.HasErrors || t.OutOfChars) )
{
Token next = t.NextToken();
switch (next.type)
{
case TokenType.TOK_EOL: // empty lines are ok
break;
case TokenType.TOK_TITLE: // we have a title
getTitle(t,ans);
break;
case TokenType.TOK_NOTE: // we have a note
getNote(t, ans);
break;
case TokenType.TOK_IDENTIFIER:
parseIdentifier(t, ans, next);
break;
default: // anything else is a problem!
ans.HasErrors = true;
break;
}
}
return ans;
}
private static void getTitle(Tokenizer t, Diagram d)
{
Token str = t.NextToken();
if(str.type == TokenType.TOK_STRING) {
d.Title = str.data;
}
else
{
d.HasErrors = true;
}
}
private static void parseArrow(Tokenizer t, Diagram d, Actor left)
{
Token rightID = t.NextToken();
// this should be an identifier... or SELF...
Actor right = null;
switch (rightID.type)
{
case TokenType.TOK_IDENTIFIER:
right = d.MaybeNewActor(rightID.data);
break;
case TokenType.TOK_SELF:
right = left;
break;
default:
d.HasErrors = true;
return;
}
// we definitely have a line now...
var line = d.AddLine(left, right);
// OK, now we have a possible DASHED and STRING...
Token rest = t.NextToken();
while (rest.type != TokenType.TOK_EOL)
{
switch (rest.type)
{
case TokenType.TOK_DASHED:
line.Dashed = true;
break;
case TokenType.TOK_STRING:
line.Desc = rest.data;
break;
default:
d.HasErrors = true;
return;
}
rest = t.NextToken();
}
}
private static void parseIdentifier(Tokenizer t, Diagram d, Token first)
{
// OK, we got an identifier... let's make sure the Diagram knows about it...
Actor left = d.MaybeNewActor(first.data);
// Valid continuations are:
// EOL ... just define the actor so we have a good order
// STRING EOL ... define the actor with a display name
// TO ID [DASHED] [STRING] EOL ... define an arrow
Token second = t.NextToken();
switch (second.type)
{
case TokenType.TOK_EOL: // no problem here...
break;
case TokenType.TOK_STRING: // giving a display name...
left.DisplayName = second.data;
break;
case TokenType.TOK_TO: // defining an arrow...
parseArrow(t, d, left);
break;
default: // something went wrong here...
d.HasErrors = true;
break;
}
}