/*
 * Class what_if_t is the model of student what if processing.  See the spec
 * for detailed discussion of what this processing.
 */

#ifdef TESTING
#include WhatIf-test-stubs.h
#end


class what_if_t
{
  public:
    what_if_t(roster_t* current_roster);
    /*
     * Construct with the given roster.
     */

    what_if_t();
    /*
     * Construct with an intially empty roster.
     */
    
    ~what_if_t(); 
    /*
     * Destruct normally.
     */

    set_view(what_if_ui_t* what_if_ui);
    /*
     * Set the companion view pointer to that given.
     */

    void do_what_if(char* student_id);
    /*
     * Initiate the whatif computation and ensuing dialog for the given
     * student.  Display the what_if dialog view if it's not already.
     */

    void recompute(string_list_t* list);
    /*
     * Respond to the user pressing the Recompute button, which basic what if
     * computation.
     */

    void restore();
    /*
     * Respond to the user pressing the Restore button, which reinstates the
     * original row data from the roster.
     */

    void done();
    /*
     * Respond to the user pressing the Done button, which closes the display
     * window.
     */

  protected:
    roster_t* curent_roster;	/* Supporting roster process */
    what_if_ui_t* ui;		/* Companion view */    
    row_t* current_row;		/* Current working row data, as modified by the
				 * user  */
    row_t* original_row;	/* Original row data from the roster. */
};