using System;

public class Program
{
	public static string input_selection;
	public static string output_selection;

	public static void Main()
	{
		//Where the code actually starts
		menu_input();
	}

	public static void menu_draw()
	{
		Console.WriteLine("Hi, What data type you want to input?");
		Console.WriteLine("");
		Console.WriteLine("   +---------------[OPTION]-----------[EXAMPLE]-----[FUNCTIONALITY]-----+");
		Console.WriteLine("   | 1)     Base 10:   Decimal         '42'         (FULLY WORKING)     |");
		Console.WriteLine("   | 2)     Base 16:   Hexadecimal     '2A'         (NEARLY)            |");
		Console.WriteLine("   | 3)     Base 2:    Binary          '101010'     (NO)                |");
		Console.WriteLine("   +--------------------------------------------------------------------+");
	}

	public static void menu_input()
	{
		menu_draw();
		//Variable assignment
		string string_input = Console.ReadLine();
		//Checks if the user input is a valid option
		switch (string_input.ToUpper())
		{
			case "1":
			case "BASE 10":
			case "DECIMAL":
			case "DENARY":
				input_selection = "decimal";
				Console.WriteLine("Okay, " + input_selection + " it is:");
				menu_output();
				break;
			case "2":
			case "BASE 16":
			case "HEX":
			case "HEXADECIMAL":
				input_selection = "hex";
				Console.WriteLine("Okay, " + input_selection + " it is:");
				menu_output();
				break;
			case "3":
			case "BASE 2":
			case "BINARY":
				input_selection = "binary";
				Console.WriteLine("Okay, " + input_selection + " it is:");
				menu_output();
				break;
			default:
				Console.WriteLine("Invalid input, try again.\n\n");
				menu_input();
				break;
		}
	}

	public static void menu_output()
	{
		menu_draw();
		//Variable assign
		string string_output = Console.ReadLine();
		//Variable assign
		//Checks if the user input is a valid option
		switch (string_output.ToUpper())
		{
			case "1":
			case "BASE 10":
			case "DECIMAL":
			case "DENARY":
				Console.WriteLine("Okay, converting " + input_selection + " to decimal:");
				output_selection = "decimal";
				forward_onto();
				break;
			case "2":
			case "BASE 16":
			case "HEX":
			case "HEXADECIMAL":
				Console.WriteLine("Okay, converting " + input_selection + " to hexadecimal:");
				output_selection = "hex";
				forward_onto();
				break;
			case "3":
			case "BASE 2":
			case "BINARY":
				Console.WriteLine("Okay, converting " + input_selection + " to binary:");
				output_selection = "binary";
				forward_onto();
				break;
			default:
				Console.WriteLine("Invalid input, try again.\n\n");
				menu_output();
				break;
		}
	}

	public static string data_input()
	{
		Console.WriteLine("Enter a " + input_selection + " value:");
		string data_input = Console.ReadLine();
		return data_input;
	}

	public static void forward_onto()
	{
		switch (input_selection)
		{
			case "decimal":
				switch (output_selection)
				{
					case "decimal":
						decimal2decimal();
						break;
					case "hex":
						decimal2hex();
						break;
					case "binary":
						decimal2binary();
						break;
					default:
						Console.Write("Error");
						break;
				}

				break;
			case "hex":
				switch (output_selection)
				{
					case "decimal":
						hex2decimal();
						break;
					case "hex":
						hex2hex();
						break;
					case "binary":
						hex2binary();
						break;
					default:
						Console.Write("Error");
						break;
				}

				break;
			case "binary":
				switch (output_selection)
				{
					case "decimal":
						binary2decimal();
						break;
					case "hex":
						binary2hex();
						break;
					case "binary":
						binary2binary();
						break;
					default:
						Console.Write("Error");
						break;
				}

				break;
			default:
				Console.Write("Error");
				break;
		}
	}

	public static void decimal2decimal()
	{
		Console.Write("Wow you're an idiot, " + input_selection + " and " + output_selection + " are the same thing!\nTry again!");
		Console.WriteLine("\n\n\n");
		menu_draw();
		menu_input();
	}

	public static void decimal2hex()
	{
		char[] hex = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
		string input = "";
		input = data_input();
		decimal_check(input);
		//Variable assign
		long hexinput = 0;
		string hex_finalstring = "";
		//char[] output = new char[20];
		try
		{
			hexinput = Convert.ToInt64(input);
		}
		catch (FormatException)
		{
		}

		//Variable assign
		//Do all the maths stuff to get the hex value and append it to a string
		for (int i = 0; (i > 10) | (hexinput != 0); i++)
		{
			hex_finalstring += (hex[hexinput % 16]);
			hexinput = hexinput / 16;
		}

		//Do all the maths stuff to get the hex value and append it to a string
		//Return value to the main method
		result(hex_finalstring);
	}

	public static void decimal2binary()
	{
		string input = data_input();
		decimal_check(input);
		//variable assign
		string binary_finalstring = "";
		long[] binary = new long[32];
		long seperator = 1073741824;
		long int_input = 0;
		try
		{
			int_input = Convert.ToInt64(input);
		}
		catch (FormatException)
		{
		}

		bool start_binary = false;
		//variable assign
		//Do all the maths stuff to get the binary value and put it in an array
		for (int arraypos = 0; arraypos <= 31;)
		{
			if (int_input >= seperator)
			{
				int_input = int_input - seperator;
				binary[arraypos] = 1;
			}
			else
			{
				binary[arraypos] = 0;
			}

			seperator /= 2;
			arraypos++;
		}

		//Do all the maths stuff to get the binary value and put it in an array
		//Check where the binary actually starts (we want 1101 not 000000001101)
		for (int i = 0; i < 31; i++)
		{
			if (start_binary == false)
			{
				if (binary[i] == 1)
				{
					start_binary = true;
				}
			}

			if (start_binary == true)
			{
				//Append a string with the binary value of the value in each array slot
				binary_finalstring += binary[i].ToString();
			//Append a string with the binary value of the value in each array slot
			}
		}

		result(binary_finalstring);
	//Convert to an integer and return the value back to the main method
	}

	public static void hex2decimal()
	{
		char[] hex = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
		string input = data_input();
		char[] hex_char = input.ToUpper().ToCharArray();
		int[] hex_final = new int[hex_char.Length];
		bool done = false;
		bool clear = true;
		double final_hex_value = 0;
		int position = 0;
		int exponent = hex_final.Length - 1;
		for (int hex_letter = 0; hex_letter < hex_char.Length && done == false;)
		{
			for (int hex_alpha = 0; hex_alpha < hex.Length && done == false;)
			{
				/*
				Console.Write("\n\n hex_char(input): ");
				for (int i = 0; i < hex_char.Length; i++)
				{
					Console.Write(hex_char[i]);
				}

				Console.Write("\n hex_final: ");
				for (int i = 0; i < hex_final.Length; i++)
				{
					Console.Write(hex_final[i]);
				}

				Console.WriteLine("\n"+hex_char.Length + "\n" + hex_letter + "\n hex_alpha: " + hex_alpha + "\n hex_letter: " + hex_letter);
				*/
				if (hex_char[hex_letter].Equals(hex[hex_alpha]))
				{
					hex_final[hex_letter] = hex_alpha;
					hex_alpha = -1;
					hex_letter++;
				}

				if (hex_letter == hex_char.Length)
				{
					done = true;
				}

				hex_alpha++;
			}

			hex_letter++;
		}

		for (int i = hex_final.Length - 1; i != 0; i--)
		{
			if (hex_final[i] == 0)
			{
				clear = false;
				Array.Clear(hex_final, 0, hex_final.Length);
			}
		}

		if (clear == true)
		{
			for (position = 0; position != hex_final.Length; position++)
			{
				final_hex_value += hex_final[position] * (Math.Pow(16, exponent));
				exponent--;
			}

			Console.WriteLine(final_hex_value);
		}
		else
		{
			Console.WriteLine("Incorrect character entered, try again\n\n");
			hex2decimal();
		}
	}

	public static void hex2hex()
	{
		Console.Write("Wow you're an idiot, " + input_selection + " and " + output_selection + " are the same thing!\nTry again!");
		Console.WriteLine("\n\n\n");
		menu_draw();
		menu_input();
	}

	public static void hex2binary()
	{
	}

	public static void binary2decimal()
	{
	}

	public static void binary2hex()
	{
	}

	public static void binary2binary()
	{
		Console.Write("Wow you're an idiot, " + input_selection + " and " + output_selection + " are the same thing!\nTry again!");
		Console.WriteLine("\n\n\n");
		menu_draw();
		menu_input();
	}

	public static void decimal_check(string input)
	{
		long parse_check;
		if (long.TryParse(input, out parse_check) == false)
		{
			Console.WriteLine("Invalid input, try again.\n\n");
			forward_onto();
		}
		else
		{
			if ((Convert.ToInt64(input) < 1))
			{
				Console.WriteLine("Invalid input, try again.\n\n");
				forward_onto();
			}
		}
	}

	public static void result(string final)
	{
		Console.Write(final);
	}
}