module View;
from Lecture import all;
from Draw import all;
from Roster import all except ChangeStudentName, BanStudent, SetStudentMode, AnswerStudentQuestion, AnswerStudentComment;
export all;

object StudentScreen is
   components: ls:LectureScreen, ft:FontToolbar, ct:CurrentTool, np:Notepad, cp:ColorPalette; 
   description: (*
      A StudentScreen is the student user interface.
   *);
end StudentScreen;

object FontToolbar is 
   components: fl:FontName*, cf:CurrentFontName, s:CurrentSize, b:BoldStatus, i:ItalicStatus, 
      u:UnderlinedStatus;
   operations: ChangeStyle, ChangeSize, SetBold, SetItalic, SetUnderlined;
   description:(*
      FontToolbar changes the font of text.
   *);
end FontToolbar;

object FontName is string
   description:(*
      Font is the style of text.
   *);
end FontName;

object CurrentFontName is FontName
   description:(*
      CurrentFont is the font that will be used when typing.
   *);
end CurrentFontName;

object CurrentSize is integer
   description:(*
      CurrentSize is the size of the font that will be used when typing.
   *);
end CurrentSize;

object BoldStatus is boolean
   description:(*
      Font used when typing is bold when the BoldStatus is true.
   *);
end BoldStatus;

object ItalicStatus is boolean
   description:(*
      Font used when typing is bold when the ItalicStatus is true.
   *);
end ItalicStatus;  

object UnderlinedStatus is boolean
   description:(*
      Font used when typing is bold when the UnderlinedStatus is true.
   *);
end UnderlinedStatus; 

operation ChangeStyle is 
   inputs:ft:FontToolbar, f:FontName;
   outputs:ft':FontToolbar;
   precondition:
      (*f must be a predefinded font*)
      (f != nil);
   postcondition:
      (*The current font style is changed*)
      ft'.cf = f;
   description:(*
      This operation changes the font style.
   *);
end ChangeStyle;

operation ChangeSize is 
   inputs:ft:FontToolbar, s:CurrentSize;
   outputs:ft':FontToolbar;
   precondition:
      (*s must be positive*)
      (s > 0);
   postcondition:
      (*The current font size is changed*)
      ft'.s = s;
   description:(*
      This operation changes the font size.
   *);
end ChangeSize;

operation SetBold is
   inputs:ft:FontToolbar;
   outputs:ft':FontToolbar;
   precondition:
      (*none*);
   postcondition:
      (*The bold status is changed*)
      ft'.b = not ft.b;
   description:(*
      This operation changes the font to bold.
   *);
end SetBold;
   
operation SetItalic is
   inputs:ft:FontToolbar;
   outputs:ft':FontToolbar;
   precondition:
      (*none*);
   postcondition:
      (*The italic status is changed*)
      ft'.i = not ft.i;
   description:(*
      This operation changes the font to italic.
   *);
end SetItalic;

operation SetUnderlined is
   inputs:ft:FontToolbar;
   outputs:ft':FontToolbar;
   precondition:
      (*none*);
   postcondition:
      (*The underlined status is changed*)
      ft'.u = not ft.u;
   description:(*
      This operation changes the font to underlined.
   *);
end SetUnderlined;

object Notepad is string
   description:(*
      Notes is an entry field of text.
   *);
end Notepad;

operation RequestComment is
   inputs:stu:Student, oosr:OnlineOfflineStudentRoster;
   outputs:stu':Student, oosr':OnlineOfflineStudentRoster;
   precondition:(*student's activity is set to NoActivity*)
      stu.act?noact;
   postcondition:(*student's activity is set to Comment *)
      stu.act?com;
   description:(*
      This operation notifies the teacher that a student has a comment.
   *);
end RequestComment;
   

operation AskQuestion is 
   inputs:stu:Student, oosr:OnlineOfflineStudentRoster;
   outputs:stu':Student, oosr':OnlineOfflineStudentRoster;
   precondition:(*student's activity is set to NoActivity*)
      stu.act?noact;
   postcondition:(*student's activity is set to Question *)
      stu'.act?ques;
   description:(*
      This operation notifies the teacher that a student has a question.
   *);
end RequestComment;

end View;