/*********************************************************************
	Ed Yakabosky  CSE 103  Section 003
	This is the second homework program for CSE 103.  Its purpose is
		to build a math tutor for a student learning basic arithmetic.
		The program will randomly generate two numbers and create
		addition, subtraction, multiplication, and division problems.
		Students will be told if their answers are correct or not.
	input: none.
	output: arithmetic problems, correct or not.
*********************************************************************/

#include <iostream>
#include <iomanip>
#include <cstdlib>

using namespace std;

bool quit = false;      //initializes a boolean that determines whether 
						//program exits or not.
bool mainmenu = false;  //initializes a boolean that determienes whether 
						//program goes to main menu.
int difficulty = 0;     //initializes an integer for selecting difficulty level.
int mathtype = 0;       //initializes an integer for selecting type of computation.
int numA = 0;           //initializes an integer that represents first number
						//in computation.
int numB = 0;           //initializes an integer that represents second number 
						//in computation.
int result = 0;         //initializes an integer that is the result of computation.
int guess = 0;          //initializes an integer that is the student inputs to 
						//guess result.

int main()
{
	while (!quit)
	{
		/* This block of code outputs the Difficulty Selection Menu to the console */
		mainmenu = false;  /* mainmenu is reset to false everytime the Difficulty Menu is
						      visited so that the cases of switch (difficulty) can run.*/
		cout<<"Ed's Math Tutor 1.0\n"<<endl;
		cout<<"Please select one of the following difficulties:\n"<<endl;
		cout<<"1 - Easy\n"<<endl;
		cout<<"2 - Medium\n"<<endl;
		cout<<"3 - Hard\n"<<endl;
		cin>>difficulty;

			switch (difficulty)
			{
			//When user inputs 1 for difficulty, easy difficulty loop runs.
			case 1: while (!mainmenu)
					{
					//This outputs the menu where student selects desired type
					//of computation.
					cout<<"Please select one of the following"<<
						cout<<" arithmetic problems:\n"<<endl;
					cout<<"1 - Addition\n"<<endl;
					cout<<"2 - Subtraction\n"<<endl;
					cout<<"3 - Back to Difficulty Menu\n"<<endl;
					cout<<"4 - Quit Program\n"<<endl;
					cin>>mathtype;

						switch (mathtype)
						{
						/* When user selects 1 for mathtype, an addition problem 
						   is generated. The student enters a guess for the sum 
						   and the program returns whether the guess is correct 
						   or not. It then calls a break and returns to the 
						   previous menu.*/
						case 1: numA = (rand() % 10) + 1;
								numB = (rand() % 10) + 1;
								result = numA + numB;
								cout<<"\n"<<numA<<" + "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						/* When user selects 2 for mathtype, a subtraction problem 
						   is generated. The student enters a guess for the 
						   difference and the program returns whether the guess is 
						   correct or not. It then calls a break and returns to the 
						   previous menu.*/
						case 2: numA = (rand() % 10) + 1;
								numB = (rand() % 10) + 1;
								result = numA - numB;
								cout<<"\n"<<numA<<" - "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						case 3: mainmenu = true; //Returns student to Difficulty Menu.
							    break;
						case 4: mainmenu = true; //Exits program.
								quit = true;
								cout<<"\nGoodbye!!!"<<endl;
								return 0;
								break;
						//Tells student to enter a choice 1-5 when they fail to do so.
						//mathtype does not meet requirments for any specific case.
						default: cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								 cout<<"Please enter a valid choice.\n"<<endl;
							     cout<<setw(80)<<setfill('-')<<"\n"<<endl;
						}
					}

				//When user inputs 2 for difficulty, medium difficulty loop runs.
			case 2: while (!mainmenu)
					{
					//This outputs the menu where student selects desired type
					//of computation.
					cout<<"Please select one of the following"<<
						cout<<"arithmetic problems:\n"<<endl;
					cout<<"1 - Addition\n"<<endl;
					cout<<"2 - Subtraction\n"<<endl;
					cout<<"3 - Multiplication\n"<<endl;
					cout<<"4 - Back to Difficulty Menu\n"<<endl;
					cout<<"5 - Quit Program\n"<<endl;
					cin>>mathtype;
						switch (mathtype)
						{
						/* When user selects 1 for mathtype, an addition problem
						   is generated. The student enters a guess for the sum 
						   and the program returns whether the guess is correct 
						   or not. It then calls a break and returns to the 
						   previous menu.*/
						case 1: numA = (rand() % 50) + 1;
								numB = (rand() % 50) + 1;
								result = numA + numB;
								cout<<"\n"<<numA<<" + "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						/* When user selects 2 for mathtype, a subtraction problem 
						   is generated. The student enters a guess for the 
						   difference and the program returns whether the guess is 
						   correct or not. It then calls a break and returns to the 
						   previous menu.*/
						case 2: numA = (rand() % 50) + 1;
								numB = (rand() % 50) + 1;
								result = numA - numB;
								cout<<"\n"<<numA<<" - "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						/* When user selects 3 for mathtype, a multiplication problem
						   is generated. The student enters a guess for the sum and 
						   the program returns whether the guess is correct or not. 
						   It then calls a break and returns to the previous menu.*/
						case 3: numA = (rand() % 10) + 1;
								numB = (rand() % 10) + 1;
								result = numA * numB;
								cout<<"\n"<<numA<<" * "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						case 4: mainmenu = true; //Returns student to Difficulty Menu.
							    break;
						case 5: mainmenu = true; //Exits program.
								quit = true;
								cout<<"\nGoodbye!!!"<<endl;
								return 0;
								break;
						//Tells student to enter a choice 1-5 when they fail to do so.
						//mathtype does not meet requirments for any specific case.
						default: cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								 cout<<"Please enter a valid choice.\n"<<endl;
							     cout<<setw(80)<<setfill('-')<<"\n"<<endl;
						}
					}
					
			//When user inputs 3 for difficulty, hard difficulty loop runs.
			case 3: while (!mainmenu)
					{
					//This outputs the menu where student selects desired type
					//of computation.
					cout<<"Please select one of the following"<<
						cout<<"arithmetic problems:\n"<<endl;
					cout<<"1 - Addition\n"<<endl;
					cout<<"2 - Subtraction\n"<<endl;
					cout<<"3 - Multiplication\n"<<endl;
					cout<<"4 - Back to Difficulty Menu\n"<<endl;
					cout<<"5 - Quit Program\n"<<endl;
					cin>>mathtype;
						switch (mathtype)
						{
						/* When user selects 1 for mathtype, an addition problem 
						   is generated.The student enters a guess for the sum 
						   and the program returns whether the guess is correct 
						   or not. It then calls a break and returns to the 
						   previous menu.*/
						case 1: numA = (rand() % 100) + 1;
								numB = (rand() % 100) + 1;
								result = numA + numB;
								cout<<"\n"<<numA<<" + "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						/* When user selects 2 for mathtype, a subtraction problem 
						   is generated. The student enters a guess for the 
						   difference and the program returns whether the guess is 
						   correct or not. It then calls a break and returns to the 
						   previous menu.*/
						case 2: numA = (rand() % 100) + 1;
								numB = (rand() % 100) + 1;
								result = numA - numB;
								cout<<"\n"<<numA<<" - "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						/* When user selects 3 for mathtype, a multiplication problem 
						   is generated. The student enters a guess for the sum and 
						   the program returns whether the guess is correct or not. 
						   It then calls a break and returns to the previous menu.*/
						case 3: numA = (rand() % 100) + 1;
								numB = (rand() % 100) + 1;
								result = numA * numB;
								cout<<"\n"<<numA<<" * "<<numB<<" = "<<endl;
								cin>>guess;
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								if (guess == result)
								{
									cout<<"\nYou are correct!"<<endl;
								}
								else
								{
									cout<<"\nSorry, you are incorrect.\n"<<endl;
								}
								cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								break;
						case 4: mainmenu = true; //Returns student to Difficulty Menu.
							    break;
						case 5: mainmenu = true; //Exits program.
								quit = true;
								cout<<"\nGoodbye!!!"<<endl;
								return 0;
								break;
						//Tells student to enter a choice 1-5 when they fail to do so.
						//mathtype does not meet requirments for any specific case.
						default: cout<<setw(80)<<setfill('-')<<"\n"<<endl;
								 cout<<"Please enter a valid choice.\n"<<endl;
							     cout<<setw(80)<<setfill('-')<<"\n"<<endl;
						}
					}

			//Tells student to select a difficulty again when number entered for
			//difficulty does not satisfy requirements for any specific case.
			default: cout<<setw(80)<<setfill('-')<<"\n"<<endl;
					 cout<<"\nPlease select again."<<endl;
			         cout<<setw(80)<<setfill('-')<<"\n"<<endl;
			}
	}
	return 0;
}