hw6_fncts.h

/*

Programmer: Jennifer Leopold

File: hw6_functs.h

Purpose: This file contains the function prototypes for

the HW #6 vending machine program.

*/

#ifndef HW6_H

#define HW6_H

#include <iostream>

#include <cstdlib>

#include <string>

using namespace std;

// ******************************************************

// Constants

// Menu selections

const string MENU_ITEM_1 = "Ginko Root";

const string MENU_ITEM_2 = "Mandrake Root";

const string MENU_ITEM_3 = "Ginseng Root";

const string MENU_ITEM_4 = "Square Root";

const string MENU_ITEM_5 = "Vitamin R Root";

const string MENU_ITEM_QUIT = "Quit";

const int NUM_MENU_ITEMS = 6;

// Price for each menu item

const float MENU_ITEM_1_PRICE = 4.5;

const float MENU_ITEM_2_PRICE = 1.23;

const float MENU_ITEM_3_PRICE = 2.39;

const float MENU_ITEM_4_PRICE = 99.98;

const float MENU_ITEM_5_PRICE = 0.78;

// Initial quantity of each menu item

const int MENU_ITEM_1_QTY = 5;

const int MENU_ITEM_2_QTY = 12;

const int MENU_ITEM_3_QTY = 12;

const int MENU_ITEM_4_QTY = 12;

const int MENU_ITEM_5_QTY = 12;

const string OUT_OF_STOCK = " *NO LONGER AVAILABLE* ";

const int NUM_MENU_SELECTION_COMMENTS = 7;

// Snarky error messages

const string ATTENTION_MSG = "Can't you read? It says";

const string TRY_AGAIN1 = "Sigh...let's try this again.";

const string TRY_AGAIN2 =

"Take a deep breath and think VERY carefully.";

const string TRY_AGAIN3 =

"Really...would that make sense on ANY planet?";

const string TRY_AGAIN4 =

"Out of curiosity, are you related to Ralph Wiggum?";

// Sales tax rates

const float TAX_RATE_SMALL_PURCHASES = 0.5;

const float TAX_RATE_MED_PURCHASES = 0.27;

const float TAX_RATE_LARGE_PURCHASES = 0.02;

const float SMALL_PURCHASE_LIMIT = 100;

const float MED_PURCHASE_LIMIT = 300;

// Amount that program multiplies user's desired qty by

const int QUANTITY_MULTIPLIER = 2;

// ******************************************************

// Function prototypes

// Generate a random number within a specified range.

// Preconditions: Parameter low is <= parameter high.

// Postconditions: A value >= low and <= high is returned.

int myRand(const int low, const int high);

// Display a greeting to the user and get input for his/her

// name.

// Preconditions: None

// Postconditions: The user's name is returned.

string greetUser();

// Display a sign-off message to the user.

// Preconditions: Parameter customerName contains the name of

// the customer, which will be included in the sign-off message.

// Postconditions: A sign-off message has been output to the

// screen.

void signOff(const string customerName);

// Display a menu of vending item selections.

// Preconditions: Parameters numMenu1..numMenu5 contain the

// available quantities of the respective menu items.

// Postconditions: A menu has been output to the screen. If

// an item is no longer available, a message to that effect has

// been output next to that selection.

void displayMenu(const int numMenu1, const int numMenu2,

const int numMenu3, const int numMenu4,

const int numMenu5);

// Prompt the user to enter a menu selection. This may be

// overridden by a selection randomly made by the program.

// Preconditions: None

// Postconditions: A valid menu selection is returned and a

// snarky comment randomly selected by the program has been

// displayed on the screen.

int getMenuSelection();

// Generate a snarky message about a specified menu choice.

// Preconditions: Parameter menuChoice should contain a (possibly

// invalid) menu selection.

// Postconditions: A snarky message about a menu choice

// will be returned.

string randomMenuChoiceMsg(const int menuChoice);

// Prompt the user to enter a quantity of an item. This may be

// overridden by a selection randomly made by the program.

// Preconditions: Parameter numAvailable is the amount of the

// selected item that is available, and itemName is the name

// of the selected item.

// Postconditions: An amount > 0 and <= numAvailable is returned

// and a snarky comment randomly selected by the program has

// been displayed on the screen.

int getQuantityInput(const int numAvailable,

const string itemName);

// Make a snarky comment based on comparing the quantity that

// computer is suggesting vs. the quantity that the user wants.

// Preconditions: Parameters computerQty and userQty contain

// non-negative values.

// Postconditions: A snarky comment randomly selected by the

// program has been displayed on the screen.

void commentOnQuantity(const int computerQty, const int userQty);

// Add tax to the total charges on items purchased.

// Preconditions: Parameter total contains a (non-negative)

// amount representing the total cost of items purchased.

// Postconditions: Pass-by-reference parameter total has been

// modified to include tax.

void applyTax(float &total);

// Prompt the user to enter payment for his/her total purchases

// and output change due.

// Preconditions: Parameter total should contain a non-negative

// amount representing total purchases plus tax, and customerName

// should contain the user's name.

// Postconditions: A message about change that the user is due

// (following payment) will have been displayed on the screen.

void getPaid(const float total, const string customerName);

#endif