// Operation.pp
//
// Created by Cristina Videira Lopes on 12/20/94.
//
// This file contains the set of propagation patterns whose source vertex
// is the Operation class; the operations defined here apply to objects
// of this class. These are the current propagation patterns:
//
//   *operation* void execute (IN LibrarySystem* ls)
//


//
// *operation* void execute (LibrarySystem* ls)
//
// Execute the operation correspondent to a given operation-object within
// a LibrarySystem. The LibrarySystem-object is given as input for possible
// calls to it.
//
*operation* void execute (LibrarySystem* ls)
  *traverse*
    *from* Operation *to* 
           {Exit, ShowBooks, SearchBook, ShowUsers, SearchUser, CheckOut, CheckIn, Invalid}

  *carry* *in* User *u = (@ NULL @),
               CheckedOut_List* col = (@ NULL @),
               Book_List *bl = (@ new Book_List @), 
               Copy_List *cl = (@ new Copy_List @)
    *along* *from* CheckBook *to* {CheckOut, CheckIn}


  *wrapper* ShowBooks *prefix*
  (@ ls->show_books(); @)

  *wrapper* SearchBook *prefix*
  (@ 
   char keyword[256];
   Book_List *bl = new Book_List;
   cout << " Enter keyword: ";
   cin >> keyword;

   ls->search_book (keyword, bl);
   bl->print();
  @)

  *wrapper* ShowUsers *prefix*
  (@ ls->show_users(); @)

  *wrapper* SearchUser *prefix*
  (@ 
   char key[256];
   User_List *ul = new User_List;
   cout << " Enter part of name or address: ";
   cin >> key;

   ls->search_user (key, ul);
   ul->print();

  @)

  *wrapper* CheckBook *prefix*
  (@ 
   char uid[30], isbn[30], copy[30];

   // ATTENTION! set user u
   cout << " Checking books.\n Enter user id: ";
   cin >> uid;
   u = ls->get_users()->search_user(atoi(uid));
   if (u == NULL) {
     cout << " Invalid user id.\n";
     return;
   }

   // ATTENTION! set checked out list col
   col = u->get_checkedoutlist();

   for (;;) {
     cout << " Enter book isbn (or 0 to terminate): ";
     cin >> isbn;
     if (atoi (isbn) <= 0) break;
     Book *b = ls->get_books()->search_book (atoi (isbn));
     if (b == NULL) {
       cout << " Invalid isbn.\n";
       continue;
     }

     cout << " Enter copy #: ";
     cin >> copy;
     Copy *c = b->search_copy (atoi(copy));
     if (c == NULL) {
       cout << " Invalid copy for this book.\n";
       continue;
     }

     // ATTENTION! update booklist bl and copylist cl
     bl->append (b);
     cl->append (c);
   }
  @)

  *wrapper* CheckOut *prefix*
  (@
   // Here we have all the necessary information:
   // User (u), list of books checked out by user (col), list of books to be
   // checked out (bl) and their copies (cl).

   Book_list_iterator next_book (*bl);
   Copy_list_iterator next_copy (*cl);
   Book *b; Copy *c; CheckedOut *co;
   int i = 0;

   while (b = next_book()) {
     c = next_copy();
     // Check the status
     if (u->quota() == col->list_length ()) {
       cout << " Quota exceeded by this user. "
            << "Can't check out the last "
            << (bl->list_length() - i) << " books:\n";
       break;
     }
     c->set_borrower (u);
     co = new CheckedOut;
     co->set_book (b);
     co->set_copy (c);
     col->append (co);
     i++;
   }

  @)

  *wrapper* CheckIn *prefix*
  (@

   // Here we have all the necessary information:
   // User (u), list of books checked in by user (col), list of books to be
   // checked in (bl) and their copies (cl).

   Book_list_iterator next_book (*bl);
   Copy_list_iterator next_copy (*cl);
   Book *b; Copy *c; CheckedOut *co;
   CheckedOut_List *new_col = NULL;
   int found;

   while (b = next_book()) {
     c = next_copy();

     new_col = new CheckedOut_List;
     found = 0;

     CheckedOut_list_iterator next_co (*col);
     while (co = next_co()) {
       if ((co->get_book() == b) && (co->get_copy() == c)) { /* found */
	 c->set_borrower (NULL);
	 delete co;
	 found = 1;
       }
       else new_col->append (co);
     }
     col = new_col;
     if (!found) {
       cout << " Book " << *b->get_isbn()->get_n() 
            << " not borrowed by user " << *u->get_uid() << "\n";
     }
     else col = new_col;
   }

   u->set_checkedoutlist (new_col);

  @)

  *wrapper* Invalid *prefix*
  (@ cout << " Invalid operation. Please try again.\n"; @)