Library.cpp

// File: Library.cpp

// Programmer: Robert Doobay

// Class: COP 2931

// Description: This program simulates the checking out and checking in of books
// from a library.  Book data and library card data is read in from books.txt
// and cards.txt and stored in separate arrays of their respective object types.
// When the program user is finished making changes to the database, the
// existing text files are deleted and new ones are created to reflect all
// changes made.

// book.h url:http://pastebin.com/DvKxhBgy
// card.h url:http://pastebin.com/yEs6USpp


// BEGIN PROGRAM

#include <iostream>
#include <fstream>
#include <string>
#include <stdio.h>
#include "card.h"
#include "book.h"
using namespace std;

// Local Functions
void ShowMenu();
Card createCard(string name, string phone, int holderID);

int main()
{
    // int i and j will be variables for loops
    int i = 0;
    int j = 0;
    // int command will be used to store the user's choice for the menu
    int command = 0;

    // These variables are used and reused for data entry/retrieval purposes
    string name;
    string phone;
    string holderID;
    string bookID;
    string title;
    string author;
    string checked;

    // These variables store important indices for the book and card arrays
    // They will be used when the loop finds the index it's looking for
    int cardnum;
    int booknum;

    // These will be used to read in data from the text files
    char lineInput[100];
    char *buffer;


    // Declare an array of 20 cards

    Card cards[20];

    // Declare an array of 20 books

    Book books[20];

    // Declare a file pointer and open the cards file

    FILE *cardlist = fopen("cards.txt", "r");
    if (cardlist == NULL) perror ("Error opening \"cards.txt\"");
    else
    {

        // Read in lines from the file


        // As long as it doesn't encounter a NULL character, this loop will
        // read in data, token by token, into the cards array.

        for (i = 0; i < 20 && fgets(lineInput, 100, cardlist) != NULL; i++)
        {
            cout << "Loading card...";

            buffer = strtok(lineInput, ","); // gets token until the first comma

            name = buffer;
            buffer = strtok(NULL, ","); // gets second token until second comma
            buffer++;                   // skips the space

            phone = buffer;
            buffer = strtok(NULL, ","); // gets third token until third comma
            buffer++;                   // skips space

            holderID = buffer;
            buffer = strtok(NULL, ","); // gets fourth token until fourth comma
            buffer++;                   // skips space, ends at last token

            bookID = buffer;            // last assignment

            // Store all assigned tokens in the array at index i

            cards[i] = Card(name, phone, stoi(holderID));

            cout << "DONE" << endl;
            // If card has a checked book, it will assign the book to the card

            if (stoi(bookID) != 0)
            {
                cards[i].changeBook(stoi(bookID));
            }
        }
    }

    // Declare a file pointer and open the books file

    FILE *booklist = fopen("books.txt", "r");
    if (booklist == NULL) perror ("Error opening \"books.txt\"");
    else
    {

        // Read the lines from the file

        // As long as it doesn't encounter a NULL character, this loop will
        // read in data, token by token, into the cards array.

        for (i = 0; i < 20 && fgets(lineInput, 100, booklist) != NULL; i++)
        {
            cout << "Loading book...";

            buffer = strtok(lineInput, ","); // gets token until the first comma

            title = buffer;
            buffer = strtok(NULL, ","); // gets second token until second comma
            buffer++;

            author = buffer;
            buffer = strtok(NULL, ","); // gets third token until third comma
            buffer++;

            bookID = buffer;
            buffer = strtok(NULL, ","); // gets fourth token until fourth comma
            buffer++;

            checked = buffer;
            buffer = strtok(NULL, ","); // gets fifth token until fifth comma
            buffer++;                   // skips space, ends at last token

            holderID = buffer;         // last assignment

            // Store all assigned tokens in the array at index i

            books[i] = Book(title, author, stoi(bookID));
            cout << "DONE" << endl;

            // If it's checked out, it will assigns the card ID to the book

            if (checked != "false")
            {
                books[i].changeHold(stoi(holderID));
            }
        }
    }

    cout << endl;

    // Display Main Menu

    while(command != 6) // Listens for value 6, which will shut down application
    {
        ShowMenu();     // Show Menu

        cin >> command; // Await user input

        switch (command)    // Switch statement to process user input
        {
            case 1:     // Display Book List

                // Parse through cards and check for absence of initialization.
                // The loop will terminate not just if i==20, it will also
                // terminate if the initialization check fails.
                // This is to prevent junk output.
                // If i==20, then the array is full of cards.

                for (i = 0; i < 20 && (cards[i].checkInit() != 0); i++)
                {
                    // Print separator
                    cout << "\n" << endl;

                    // Print card information
                    cards[i].getInfo();

                    // Check if card has checked book
                    if(cards[i].getStatus() == 0)
                    {
                        cout.width(8); cout << "Books: " << "NONE" << endl;
                    }

                    else
                    {
                        // Parse array of books and find book name
                        // If i does not reach 20, the book ID was found
                        // If i==20, then the book ID was not found
                        for (j = 0; j < 20 && books[j].getID() != cards[i].getBook(); j++);

                        if (j == 20)
                        {
                            cout.width(8); cout << "Error: Unknown Book" << endl;
                        }

                        // Print book name
                        else
                        {
                            cout.width(8); cout << "ON HAND: " <<  books[j].getTitle() << endl;
                        }
                    }
                }

                // Print separator
                cout << "\n" << endl;

                // Throw alert if card array is full
                if (i == 20) cout << "\nCARD LIST FULL\n" << endl;

                break;

            case 2:     // Display Card List

                // Parse through books and check for absence of initialization.
                // The loop will terminate not just if i==20, it will also
                // terminate if the initialization check fails.
                // This is to prevent junk output.
                // If i==20, then the array is full of cards.

                for (i = 0; i < 20 && books[i].checkInit() != 0; i++)
                {
                    // Print separator
                    cout << "\n" << endl;

                    // Print book information
                    books[i].getInfo();
                }

                // Print Separator
                cout << "\n\n" << endl;
                break;

            case 3:     // Check Out A Book

                // Await user input for card ID and book ID
                cout << "Please enter the ID of the person checking out: ";
                cin >> holderID;
                cout << "Please enter the ID of the book to check out: ";
                cin >> bookID;

                cout << endl;

                // Parse through cards and check for matching IDs.
                // If i==20, then the card ID was not found.
                // If loop breaks before i==20, then the card ID was found

                for (i = 0; i < 20 && cards[i].getID() != stoi(holderID); i++);

                if (i == 20)
                {
                    cout << "Error: Person ID not found.\n" << endl;
                    break;
                }

                // Store index if person is found
                cardnum = i;

                // Parse through books and check for matching IDs.
                // If i==20, then the book ID was not found.
                // If loop breaks before i==20, then the book ID was found

                for (i = 0; i < 20 && books[i].getID() != stoi(bookID); i++);

                // Throw alert if book not found
                if (i == 20)
                {
                    cout << "Error: Book ID not found.\n" << endl;
                    break;
                }

                // Store index if book is found
                booknum = i;

                // Check if book is already checked out
                if (books[booknum].getStatus() != 0)
                {
                    // Parse through cards to find person who checked out book
                    // by comparing book holder ID with card ID
                    // If i==20, then an unknown user has the book.
                    // If loop breaks before 20, then the card ID was found

                    for (i = 0; i < 20 && cards[i].getID() != books[booknum].whoHas(); i++);

                    if (i == 20)
                    {
                        // Throw error if card ID not found
                        cout << "Error: This book is checked out by UNKNOWN\n" << endl;
                    }

                    // Print name of person who checked out the book
                    else cout << cards[i].getName() << " currently has this book." << endl;

                    cout << "Please try again after this book is checked back in." << endl;
                    cout << "\n";
                    break;
                }

                // Check if person attempting to check out book has a book
                // he needs to return by checking his card status
                if (cards[cardnum].getStatus() != 0)
                {
                    // Throw error if he has already has checked out book
                    cout << cards[cardnum].getName() << " must return his book before "
                    << "checking out a new one.\n" << endl;
                    break;
                }

                // If no errors were encountered, proceed with book checkout.
                // Assign book ID to card, and card ID to book.
                books[booknum].changeHold(stoi(holderID));
                cards[cardnum].changeBook(stoi(bookID));

                // Print success message with name
                cout << "Book checkout to " << cards[cardnum].getName() << " successful.\n" << endl;

                break;

            case 4:     // Return A Book

                // Await user input
                cout << "Please enter the ID of the person returning: ";
                cin >> holderID;

                cout << "Please enter the ID of the book to return: ";
                cin >> bookID;

                cout << endl;

                // Parse through cards and check for matching IDs.
                // If i==20, then the card ID was not found.
                // If loop breaks before i==20, then the card ID was found

                for (i = 0; i < 20 && cards[i].getID() != stoi(holderID); i++);

                // Throw error if ID is not found
                if (i == 20)
                {
                    cout << "Error: Person ID not found\n" << endl;
                    break;
                }

                // Store index if card is found
                cardnum = i;

                // Parse through books and check for matching IDs.
                // If i==20, then the book ID was not found.
                // If loop breaks before i==20, then the book ID was found
                for (i = 0; i < 20 && books[i].getID() != stoi(bookID); i++);

                // Throw error if book is not found
                if (i == 20)
                {
                    cout << "Error: Book ID not found.\n" << endl;
                    break;
                }

                // Store index if book is found
                booknum = i;

                // Check if book is already checked in
                if (books[booknum].getStatus() != 1)
                {
                    cout << "That book is already in our inventory.\n" << endl;
                }

                // Check if user has any books checked out
                if (cards[cardnum].getStatus() != 1)
                {
                    cout << "You do not have any checked books to return.\n" << endl;
                }

                // If either error was thrown, then break operation
                if (books[booknum].getStatus() != 1 || cards[cardnum].getStatus() != 1) break;

                // If no errors were encountered, then proceed with book return
                // Assign both card ID and book ID to 0
                cards[cardnum].resetHold();
                books[booknum].resetHold();

                // Print success message with name
                cout << "Book return from " <<  cards[cardnum].getName() << " successful.\n" << endl;

                break;

            case 5:     // Create A Card

                // Await user input
                cout << "Please enter the name for the card: ";

                // Flush stream
                cin.ignore();
                getline(cin, name);
                cout << "Please enter the phone number for the card: ";
                cin >> phone;
                cout << "Please enter the user ID desired: ";
                cin >> holderID;

                cout << endl;

                // Parse through cards and check for matching IDs.
                // If i==20, then no matching IDs were found.
                // If loop breaks before i==20, then the card ID was found
                // If a card ID is found, then it will throw an error, since
                // there cannot be two matching IDs.

                for (i = 0; i < 20 && cards[i].getID() != stoi(holderID); i++);

                // Throw error if ID is found
                if (i != 20)
                {
                    cout << "Error: That ID is already taken.\n" << endl;
                    break;
                }

                // Parse through cards and stop when uninitialized space
                // is encounered.
                // If i==20, then the array is full.
                // If loop breaks before i==20, then a space was found to
                // store the new card.

                for(i = 0; i < 20 && cards[i].checkInit() != 0; i++);

                // Throw alert if array is full
                if (i == 20)
                {
                    cout << "Error: no more cards can be added." << endl;
                    cout << "Please try again later.\n" << endl;
                    break;
                }

                // If no errors were encountered, then append new card to array
                cards[i] = createCard(name, phone, stoi(holderID));

                // Print success message with name
                cout << "Card successfuly created." << endl;
                cout << cards[i].getName() << " may now check out books using their ID.\n" << endl;

                break;

            case 6:     // Quit Application
                cout << "Library Application Shutting Down...\n\n" << endl;
                break;

            default:    // Default Case
                cout << "Error: Bad Request. Select a number from the list:\n"
                << endl;
                break;
        }
    }

    // Close file pointers

    fclose(cardlist);
    fclose(booklist);

    // Create string to store concatenated lines for output

    string lineOutput;

    // Remove existing cards file and write new cards file

    if (remove("cards.txt") != 0) // Throw error message if cannot remove file
    {
        cout << "Error overwriting \"cards.txt\". Lost all changes.\n" << endl;
    }

    else
    {

        // Parse array of cards and write contents to file cardlist
        // Loop will stop if improperly initialized card is encountered or if
        // end of the array is encountered.

        cout << "Writing \"books.txt\"..."; // Alert message
        ofstream cardout("cards.txt", ios_base::app); // Create output stream

        for (i = 0; i < 20 && cards[i].checkInit() != 0; i++)
        {

            // Read card data to string with delimiters
            lineOutput = cards[i].getName() + ", "
            + cards[i].getPhone() + ", "
            + to_string(cards[i].getID()) + ", "
            + to_string(cards[i].getBook()) + "\n";

            // Write to file
            cardout << lineOutput;
        }

        // Close card file
        cardout.close();

        cout << "DONE" << endl;
    }

    // Remove existing books file and write new books file

    if (remove("books.txt") != 0) // Throw error message if cannot remove file
    {
        cout << "Error overwriting \"books.txt\". Lost all changes.\n" << endl;
    }

    else
    {

        // Parse array of books and write contents to file booklist
        // Loop will stop if improperly initialized book is encountered or if
        // end of the array is encountered.

        cout << "Writing \"books.txt\"..."; // Alert message
        ofstream bookout("books.txt", ios_base::app); // Create output stream

        for (i = 0; i < 20 && books[i].checkInit() != 0; i++)
        {

            // Read card data to string with delimiters
            lineOutput = books[i].getTitle() + ", "
            + books[i].getAuthor() + ", "
            + to_string(books[i].getID()) + ", "
            + ((books[i].getStatus() == 0)? "false" : "true") + ", "
            + to_string(books[i].whoHas()) + "\n";

            // Write to file
            bookout << lineOutput;
        }

        // Close book file
        bookout.close();

        cout << "DONE" << endl;
    }

    // End of main function

    return 0;

}

void ShowMenu()
{
    // Display Library Application menu

    cout << "    MENU\n"
    << endl;

    // List choices
    cout << "1 - Show All Library Cards" << endl;
    cout << "2 - Show All Books" << endl;
    cout << "3 - Check Out A Book" << endl;
    cout << "4 - Return A Book" << endl;
    cout << "5 - Create A New Library Card" << endl;
    cout << "6 - Exit The System" << endl;
    cout << "\n    Option: ";

}

Card createCard(string name, string phone, int holderID)
{
    // Create new card object using arguments and return object
    Card newcard = Card(name, phone, holderID);
    return newcard;
}

// END PROGRAM