#include <iostream>
#include <iomanip>
using namespace std;
 
const int floor_size = 20;
 
void mainMenu(void);
void turtleGraphics(int [][floor_size], int []);
 
int main(void)
{
    const int max_command = 256;
 
    int floor[floor_size][floor_size] = {{false},{false}};
    int command[max_command] = {false};
 
	mainMenu();
 
    cout << "\nEnter commands(max " << max_command << "): ";
    int i = 0;
    while (command[i - 1] != 9){
        cin >> command[i];
        i++;
    }
	cout << "\n" << endl;
	turtleGraphics(floor, command);
 
    return 0;
}
 
void mainMenu(void)
{
	cout << "*****" << setw(20) << "Turtle Graphics" << setw(10) << "*****" << endl;
	cout << "\nCommand" << setw(20) << "Meaning" << endl;
	cout << setw(7) << "1" << setw(20) << "Pen up" << endl;
	cout << setw(7) << "2" << setw(20) << "Pen down" << endl;
	cout << setw(7) << "3" << setw(20) << "Turn right" << endl;
	cout << setw(7) << "4" << setw(20) << "Turn left" << endl;
	cout << setw(7) << "5,10" << setw(20) << "Move forward 10"
		 << "\n" << setw(27) << "spaces (or a number" << "\n"
		 << setw(27) << "other than 10)" << endl;
	cout << setw(7) << "6" << setw(20) << "Print the" << "\n"
		 << setw(15) << floor_size << "-by-" << floor_size
		 << " array" << endl;
	cout << setw(7) << "9" << setw(20) << "End of data" << "\n"
		 << setw(27) << "(sentinel)" << endl;
}
 
void turtleGraphics(int flr[][floor_size], int cmd[])
{
	int coord_x = 0, coord_y = 0, move = 0, 
		row, column, i = 0;
	bool pen = false;
 
	while (cmd[i] != 9){
		//Uncoment next line to show coord_x and coord_y
		//cout << "X: " << coord_x << "\nY: " << coord_y << endl;
		switch(cmd[i]){
			case 1: //Don't write
				pen = false;
				break;
			case 2: //Write
				pen = true;
				break;
			case 3: //Turn rigth
				if (move == 3)
					move = 0;
				else
					move++;
				break;
			case 4: //Turn left
				if (move == 0)
					move = 3;
				else
					move--;
				break;
			case 5: // Move turtle
				i++;
				switch(move){ //Nested switch (control direction)
					case 0: //Move down
						if ((cmd[i] + coord_y) > floor_size) //Check if it is in floor limits
							cmd[i] = floor_size - coord_y - 1; //If not, set move to the limit
 
						for (row = coord_y; row < (cmd[i] + coord_y); row++)
							for (column = coord_x; column < coord_x + 1; column++)
								flr[row][column] = pen;
						coord_y = row;
						break;
					case 1: //Move rigth
						if ((cmd[i] + coord_x) > floor_size) //Check if it is in floor limits
							cmd[i] = floor_size - coord_x - 1; //If not, set move to the limit
 
						for (row = coord_y; row < coord_y + 1; row++)
							for (column = coord_x; column < (cmd[i] + coord_x); column++)
								flr[row][column] = pen;
						coord_x = column;
						break;
					case 2: //Move up
						if (cmd[i] > coord_y) //Check if it is in floor limits
							cmd[i] = floor_size - 1; //If not, set move to the limit
 
						for (row = coord_y; row > (coord_y - cmd[i]); row--)
							for (column = coord_x; column < coord_x + 1; column++)
								flr[row][column] = pen;
						coord_y = row;
						break;
					case 3: //Move left
						if (cmd[i] > coord_x) //Check if it is in floor limits
							cmd[i] = floor_size - 1; //If not, set move to the limit
 
						for (row = coord_y; row < coord_y + 1; row++)
							for (column = coord_x; column > (coord_x - cmd[i]); column--)
								flr[row][column] = pen;
						coord_x = column;
						break;
					default:
						;
				} //End nested switch
				break;
			case 6: // Print floor
				for (int i = 0; i < 20; i++){
					for (int j = 0; j < 20; j++){
						if (flr[i][j] == true)
							cout << setw(2) << "*";
						else
							cout << setw(2) << " ";
					}
				cout << endl;
				}
				break;
			default:
				;
		}
		i++;
	}
}