Record Database

#ifndef Scholarship_h
#define Scholarship_h
#include <cstring>
 /**
 * The Scholarship class holds a c-string up to length 100, and a double,
 * which correspond to the name of a scholarship, and its payout, respectively.
 *
 * @author A. Mackey
 * @version 07.05.15
 */
#define MAX_LENGTH 101
class Scholarship {
    private:
        char name[MAX_LENGTH];  // name of Scholarship
        double payout;          // payout of Scholarship
    public:
        //document these constructors properly
        Scholarship () {}
        Scholarship (char n[], double p) {
            strcpy(name, n);
            payout = p;
        }
        /**
         * Getter function for Scholarship name.
         *
         * @return <code>name</code>
         */
        char* getName();

        /**
         * Getter function for Scholarship payout.
         *
         * @return <code>payout</code>
         */
        double getPayout();

        /**
         * Setter function for Scholarship name.
         *
         * @param sname     the given name to which <code>name</code> is set.
         * @param n         the length of sname.
         */
        void setName(char sname[], int n);

        /**
         * Setter function for Scholarship payout.
         *
         * @param p     the given payout to which <code>payout</code> is set.
         */
        void setPayout(double p);
};

char* Scholarship::getName() {
    return name;
}

double Scholarship::getPayout() {
    return payout;
}

void Scholarship::setName(char sname[], int n) {
    strcpy(name, sname);
    name[n] = '\0';
}

void Scholarship::setPayout(double p) {
    payout = p;
}
#endif // Scholarship_h


/**
 * A program which takes record of given scholarships and stores them in a database.
 * The user selects from a menu of options, each of which allows them to access and
 * utilise the database through a variety of functions.
 *
 * @author A. Mackey
 * @author B. Ginther
 * @author A. Rossi
 * @author A. Westvik
 * @version 12.05.15
 */
#include "Scholarship.h"
#include <cstdlib>
#include <fstream>
#include <iostream>
using namespace std;

/*
 * note(s):
 *
 * recommend possibly adding count of spots to be filled by new records in order to
 * cut down on database management of indices
 *
 * additionally, add sort file by name/payout function(s).
 *
 * possibly reference objects instead of passing by value for add/delete functions
 *
 * add data type validation for num values
 */

/**
 * Writes <code>n</code> to the given <code>file</code>.
 *
 * @param file      database file containing (n) record(s).
 * @param n         number of records.
 */
void addToFile(fstream& file, int n);
/**
 * Appends a <code>record</code> to the given <code>file</code>.
 *
 * @param file      database file containing (n) record(s).
 * @param record    given Scholarship record object to write to file.
 */
void addToFile(fstream& file, Scholarship record);
/**
 * Allows for the deletion of a <code>record</code> within the database file.
 *
 * @param file      database file containing (n) record(s).
 * @param n         number of records.
 */
void deleteRecord(fstream& file, int& n);
/**
 * Displays all <code>record</code>s held within the database file.
 *
 * @param file      database file containing (n) record(s).
 */
void displayAllRecords(fstream& file, int n);
/**
 * Displays a <code>record</code>.
 *
 * @param record    given Scholarship record object to write to file.
 */
void displayRecord(Scholarship record);
/**
 * Adds records the database from a user-provided file.
 * <p>
 * Sequential access input file structure (by line; repeats until EOF):
 *   Scholarship name
 *   Scholarship payout
 *
 * @param file      database file containing (n) record(s).
 * @param n         number of records.
 */
void fileAddRecord(fstream& file, int& n);
/**
 * Prompts the user to select a number between 1 and <code>n</code>.
 *
 * @param i         index variable.
 * @param n         number of records.
 */
void getIndex(int& i, int n);
/**
 * Gathers input for all fields for a given <code>record</code>.
 *
 * @param record    given Scholarship record object.
 */
void setNameAndPayForRecord(Scholarship& record);
/**
 * Reports a user-based input-error.
 */
void invalidSelection();
/**
 * Prompts user to add a <code>record</code> within the database file.
 *
 * @param file      database file containing (n) record(s).
 */
void manualAddRecord(fstream& file, int& n);
/**
 * This function displays a list of menu options which allow a user access to a
 * database of records.
 *
 * @param file          database file containing (n) record(s).
 * @param countFile     file containing count (n) of records in <code>file</code>.
 */
void menu(fstream& file, fstream& countFile);
/**
 * Prompts user to modify a <code>record</code> within the database file at a
 * user-given index.
 *
 * @param file      database file containing (n) record(s).
 * @param n         number of records.
 */
void modifyRecordAtIndex(fstream& file, int n);
/**
 * Attempts to open necessary files for program operation.
 */
void openAndValidateFiles();
/**
 * Removes a <code>record</code> from the given <code>file</code>.
 *
 * @param file          database file containing (n) record(s).
 * @param record        given Scholarship record object to write to file.
 * @param sizeOfRecord  size of Scholarship object
 * @param i             index of record.
 */
void readRecord(fstream& file, Scholarship& record, int sizeOfRecord, int i);
/**
 * Removes a <code>record</code> from the given <code>file</code>.
 *
 * @param file      database file containing (n) record(s).
 * @param record    given Scholarship record object to write to file.
 * @param n         index of record.
 */
void removeFromFile(fstream& file, Scholarship record, int i);
/**
 * Searches for record(s) within the database file matching user-given fields.
 *
 * @param file      database file containing (n) record(s).
 */
void searchAndDisplayRecordByField(fstream& file, int n);
/**
 * Searches for record within the database file at user-given index.
 *
 * @param file      database file containing (n) record(s).
 * @param n         number of records.
 */
void searchAndDisplayRecordByIndex(fstream& file, int n);

int main() {
    openAndValidateFiles();

    return 0;
}

void addToFile(fstream& file, int n) {
    file.write(reinterpret_cast<char*>(&n), sizeof(int));
}

void addToFile(fstream& file, Scholarship record) {
    file.write(reinterpret_cast<char*>(&record), sizeof(Scholarship));
}

void deleteRecord(fstream& file, int& n) {
    Scholarship record;
    char chooseDelete;
    int recordNumber;

    getIndex(recordNumber, n);

    //display record
    if(n > 0) {
        file.seekg((recordNumber-1) * sizeof(record), ios::beg);
        file.read(reinterpret_cast<char*>(&record), sizeof(record));
        displayRecord(record);

        //check for deletion confirmation
        cout << "Are you sure you wish to delete this record? [Y/N]: " << endl;
        cin >> chooseDelete;
        chooseDelete = toupper(chooseDelete);
        if(chooseDelete == 'Y') {
            //delete record
            n--;
        }
        cout << endl;
    }
}

void displayAllRecords(fstream& file, int n) {
    Scholarship record;
    int recordNumber = 1;

    //read and display the records in reverse
    if(n > 0) {
        while(!file.eof()) {
            readRecord(file, record, sizeof(record), recordNumber);
            displayRecord(record);
            recordNumber++;
        }
    } else {
        cout << "There are no records to display." << endl;
    }
}

void displayRecord(Scholarship record) {
    cout << "Name: " << record.getName() << endl;
    cout << "Payout: " << record.getPayout() << endl << endl;
}

void fileAddRecord(fstream& file, int& n) {
    Scholarship record;             //object holding Scholarship record data
    char val[MAX_LENGTH];           //temporary variable to hold next line of file
    char filename[FILENAME_MAX];    //user filename
    fstream userFile;               //user file

    //get user filename and attempt to open file
    cout << "Enter a filename (Ex: file.txt): ";
    cin >> filename;
    userFile.open(filename, ios::in);

    //tests if user file exists; if it doesn't, throws error
    if(!userFile) {
        cout << "File not found.";
    }

    while(!userFile.eof() && userFile) {
        file.getline(val, MAX_LENGTH-1, '\n'); //get name line from file; set to val
        record.setName(val, strlen(val));      //set name to name stored in val
        file.getline(val, MAX_LENGTH-1, '\n'); //get pay line from file; set to val
        record.setPayout(atof(val));           //set payout to name stored in val
        addToFile(file, record);               //write record into database file
        n++;                                   //increment counter for new record
    }
    cout << endl;
}

void getIndex(int& i, int n) {
    bool invalidEntry;
    if(n > 0) {
        do {
            invalidEntry = false;
            cout << "Enter a number [1 to " << n << "]: ";
            cin >> i;
            if(cin.fail()) {
                invalidEntry = true;    //entry is invalid
                cin.clear();            //clear stream
                cin.ignore();           //ignore left over data
                invalidSelection();     //display error message
            }
        } while((i < 1 || i > n) || invalidEntry);
    } else {
        cout << "There are no records to display." << endl;
    }
}

void setNameAndPayForRecord(Scholarship& record) {
    static char name[MAX_LENGTH];
    static double payout;

    cout << "Enter name: ";
    cin >> name;
    record.setName(name, strlen(name));

    cout << "Enter payout:";
    cin >> payout;
    record.setPayout(payout);
}

void invalidSelection() {
    cout << "Invalid entry. Press any key to continue: ";
    cin.get();
    cout << endl;
}

void manualAddRecord(fstream& file, int& n) {
    Scholarship record;

    setNameAndPayForRecord(record);
    addToFile(file, record);

    n++;
}

void menu(fstream& file, fstream& countFile) {
    int menuSelection,
        counter;
    char val[MAX_LENGTH];

    if(!countFile.eof()) {
        countFile.getline(val, MAX_LENGTH-1, '\n');
        counter = atof(val);
    }

    do {

        //menu options
        cout << "Select an option from the following:" << endl;
        cout << "[1] Input file name with list of scholarships to add." << endl;
        cout << "[2] Search for record by number [1 to n] and display." << endl;
        cout << "[3] Search for record by one or more fields. Multiple records may be displayed." << endl;
        cout << "[4] Modify record [1 to n] (must enter values for each field)." << endl;
        cout << "[5] Display all records." << endl;
        cout << "[6] Add a record manually." << endl;
        cout << "[7] Delete record [1 to n]." << endl;
        cout << "[0] Quit." << endl;
        cin >> menuSelection;

        //corresponding menu actions based on selection
        switch(menuSelection) {
            case 1:
                fileAddRecord(file, counter);
                break;
            case 2:
                searchAndDisplayRecordByIndex(file, counter);
                break;
            case 3:
                searchAndDisplayRecordByField(file, counter);
                break;
            case 4:
                modifyRecordAtIndex(file, counter);
                break;
            case 5:
                displayAllRecords(file, counter);
                break;
            case 6:
                manualAddRecord(file, counter);
                break;
            case 7:
                deleteRecord(file, counter);
                break;
            case 0:
                cout << "You selected Quit. Exiting ... ";
                break;
            default:
                invalidSelection();
                break;
        }
        addToFile(countFile, counter);
        cout << endl;
    } while(menuSelection != 0);
}

void modifyRecordAtIndex(fstream& file, int n) {
    Scholarship record;
    int recordNumber;

    getIndex(recordNumber, n);
    readRecord(file, record, sizeof(record), recordNumber);
    displayRecord(record);

    if(n > 0) {
        setNameAndPayForRecord(record);
        file.seekp(recordNumber * sizeof(record), ios:: beg);
        file.write(reinterpret_cast<const char *>(&record), sizeof(record));
    }
}

void openAndValidateFiles() {
    //opens files
    fstream file;
    fstream countFile;

    file.open("sappdbase.bin", ios::in|ios::out|ios::app|ios::binary);
    countFile.open("countfile.bin", ios::in|ios::out|ios::app|ios::binary);

    //tests if database file exists; if it doesn't, creates the file
    if(!file) {
        file.close();
        file.open("sappdbase.bin", ios::in|ios::out|ios::app|ios::binary);
    }

    //tests if count file exists; if it doesn't, creates the file
    if(!countFile) {
        countFile.close();
        countFile.open("countfile.bin", ios::in|ios::out|ios::binary);
        addToFile(countFile, 0);
    }

    //continues to the menu if all necessary files are presents; exits otherwise.
    if(file && countFile) {
        menu(file, countFile);
    } else {
        cout << "Failed to locate necessary database file(s). Exiting ...";
    }

    file.close();
    countFile.close();
}

void readRecord(fstream& file, Scholarship& record, int sizeOfRecord, int i) {
    file.seekg((i-1)*sizeof(record), ios::beg);
    file.read(reinterpret_cast<char *>(&record), sizeof(record));
}

void removeFromFile(fstream& file, Scholarship record, int n) {
    //remove <code>record</code> #n from <code>file</code>
    //shift all other records down one?
}

void searchAndDisplayRecordByField(fstream& file, int n) {
    bool invalid = false;
    int fieldSelection;

    if(n > 0) {
        do {
            cout << "Search by:" << endl;
            cout << "[1] Name." << endl;
            cout << "[2] Payout." << endl;
            cout << "[3] Both." << endl;
            cin >> fieldSelection;

            switch(fieldSelection) {
                case 1:
                    //search by name
                    break;
                case 2:
                    //search by payout
                    break;
                case 3:
                    //search by both
                    break;
                default:
                    invalidSelection();
                    break;
            }
        } while(invalid);
    } else {
        cout << "There are no records to display.";
    }
    cout << endl;
}

void searchAndDisplayRecordByIndex(fstream& file, int n) {
    Scholarship record;
    int recordNumber;

    getIndex(recordNumber, n);

    if(!(recordNumber < 1 || recordNumber > n)) {
        readRecord(file, record, sizeof(record), recordNumber);
        displayRecord(record);
    }
}