// lbook.cpp
// ----------------------------------------------------------------------
// Do not modify this file.
// defines class LibraryBook
// 
// CSE 143
// Homework 2, 3
// http://www.cs.washington.edu/education/courses/143/00su/homework/
// 25 Jun 2000; Ken Yasuhara


#include <iostream.h>
#include <string.h>
#include <assert.h>

#include "lbook.h"

//////////////////////////////////////////////////////////////////////
// constructors

LibraryBook::LibraryBook() 
{
  strcpy(title, "");
  strcpy(author, "");

  ID = 0;
  borrowerID = 0;
}


LibraryBook::LibraryBook(int newID,
			 char newTitle[MAX_TITLE_LENGTH], 
			 char newAuthor[MAX_AUTHOR_LENGTH]) 
{
  assert(strlen(newTitle) > 0);
  assert(strlen(newAuthor) > 0);
  assert(newID > 0);

  strcpy(title, newTitle);
  strcpy(author, newAuthor);

  ID = newID;
  borrowerID = 0;
}


//////////////////////////////////////////////////////////////////////
// accessors

int LibraryBook::getBorrowerID() 
{
  assert(isCheckedOut());
  return borrowerID;
}


void LibraryBook::getTitle(char copiedTitle[]) 
{
  strcpy(copiedTitle, title);
}


void LibraryBook::getAuthor(char copiedAuthor[]) 
{
  strcpy(copiedAuthor, author);
}


int LibraryBook::getID() 
{
  return ID;
}


bool LibraryBook::isCheckedOut() 
{ 
  return (borrowerID != 0); 
}


//////////////////////////////////////////////////////////////////////
// I/O

void LibraryBook::printRecord()
{
  cout << "book #" << getID() << endl;

  cout << "title:\t" << title << endl;
  cout << "author:\t" << author << endl;

  cout << "out:\t";
  if (isCheckedOut()) {
    cout << "yes" << endl;
    cout << "user:\t" << getBorrowerID() << endl;
    cout << "due:\t" << getDueDate().getMonth() << "-"
	 << getDueDate().getDay() << "-"
	 << getDueDate().getYear() << endl;
  } else {
    cout << "no" << endl;
  }
}


//////////////////////////////////////////////////////////////////////
// recording book-borrowing 

// preconditions:  this book is checked out 

bool LibraryBook::isOverdue(Date today) 
{
  assert(isCheckedOut());

  if (today.compare(dueDate) < 0) {
    return true;
  }

  return false;	
}


// preconditions:  this book is overdue
//
// given current date, returns number of days by which this book is
// overdue

int LibraryBook::daysOverdue(Date today) 
{
  assert(isOverdue(today));
  int days = dueDate.dayDifference(today);
  assert(dueDate.dayDifference(today) == today.dayDifference(dueDate));
  assert(days > 0);

  return days;
}


// preconditions:  this book is checked out 

Date LibraryBook::getDueDate() 
{
  assert(isCheckedOut());
  return dueDate;
}


// preconditions:  this book is not checked out; loan duration is positive;
// borrower has not reached limit on allowed number of borrowed books

void LibraryBook::checkOut(Date today, LibraryPatron &borrower, int loanDuration) 
{
  assert(!isCheckedOut());
  assert(loanDuration > 0);
  assert(borrower.canCheckOutMore());

  borrowerID = borrower.getID();
  borrower.registerCheckOut(ID);

  dueDate = today;
  dueDate.addDays(loanDuration);
}


// preconditions: this book must be checked out; patron must be the
// one who has this book checked out, i.e. you can only return a book
// that you previousl8y borrowed

void LibraryBook::checkIn(LibraryPatron &returner)
{
  assert(isCheckedOut());
  assert(returner.hasCheckedOut(ID));
  
  borrowerID = 0;
  returner.registerCheckIn(ID);
}