import java.math.BigInteger;

public class Calculator
{
    public static void  runCommandLoop() {
        Display display = new Display();

        Memory memory = new Memory();
        memory.resetMemory();

        DisplayMode conversion = new DisplayMode();
        int modeOrdinal = 0;
        int trigMode = 0; //0 - degrees (default); 1 - radians

        String initial = Console.getStringInput("Enter number");
        display.setDisplay(initial);

        while (true) {  
            String command = Console.getStringInput("Choose a command");
            if (command.equalsIgnoreCase("off") || command.equalsIgnoreCase("exit")) {
                Console.println("Thank you for using our product!");
                break;
            }
            if (command.equalsIgnoreCase("c") || command.equalsIgnoreCase("clear")) {
                display.setDisplay("0");
                Console.println(display.getDisplay());
                String resetValue = Console.getStringInput("Enter number");
                display.setDisplay(resetValue);
            }
            if (command.equalsIgnoreCase("+") || command.equalsIgnoreCase("add")) {
                double first = Double.parseDouble(display.getDisplay());
                double second = Console.getDoubleInput("Enter number");
                double out = Core.add(first, second);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("-") || command.equalsIgnoreCase("subtract")) {
                double first = Double.parseDouble(display.getDisplay());
                double second = Console.getDoubleInput("Enter number");
                double out = Core.subtract(first, second);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("*") || command.equalsIgnoreCase("multiply")) {
                double first = Double.parseDouble(display.getDisplay());
                double second = Console.getDoubleInput("Enter number");
                double out = Core.multiply(first, second);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("/") || command.equalsIgnoreCase("divide")) {
                double first = Double.parseDouble(display.getDisplay());
                double second = Console.getDoubleInput("Enter number");
                double out = Core.divide(first, second);
                if (Double.toString(out) == "NaN" || Double.toString(out) == "Infinity" || Double.toString(out) == "-Infinity") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("sq")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Core.multiply(first, first);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("sqrt")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Core.squareRoot(first);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("^") || command.equalsIgnoreCase("pow")) {
                double first = Double.parseDouble(display.getDisplay());
                double second = Console.getDoubleInput("Enter number");
                double out = Core.exponentiation(first, second);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("/x") || command.equalsIgnoreCase("inverse")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Core.inverse(first);
                if (Double.toString(out) == "NaN" || Double.toString(out) == "Infinity" || Double.toString(out) == "-Infinity") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("+-") || command.equalsIgnoreCase("reverse")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Core.reverse(first);
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("m+")) {
                memory.addMemory(display.getDisplay());
                display.setDisplay(memory.recallMemory());
                Console.println(display.getDisplay());
            }
            if (command.equalsIgnoreCase("mrc")) {
                Console.println(memory.recallMemory());
                display.setDisplay(memory.recallMemory());
            }
            if (command.equalsIgnoreCase("mc")) {
                memory.resetMemory();
                Console.println(display.getDisplay());
            }
            if (command.equalsIgnoreCase("bin") || command.equalsIgnoreCase("binary")) {
                Console.println(conversion.switchDisplayMode(DisplayMode.Mode.Binary, display.getDisplay()));
            }
            if (command.equalsIgnoreCase("hex") || command.equalsIgnoreCase("hexadecimal")) {
                Console.println(conversion.switchDisplayMode(DisplayMode.Mode.Hexadecimal, display.getDisplay()));
            }
            if (command.equalsIgnoreCase("oct") || command.equalsIgnoreCase("octal")) {
                Console.println(conversion.switchDisplayMode(DisplayMode.Mode.Octal, display.getDisplay()));
            }
            if (command.equalsIgnoreCase("dec") || command.equalsIgnoreCase("decimal")) {
                Console.println(conversion.switchDisplayMode(DisplayMode.Mode.Decimal, display.getDisplay()));
            }
            if (command.equalsIgnoreCase("switch")) {
                Console.println(conversion.switchDisplayMode(DisplayMode.Mode.values()[modeOrdinal], display.getDisplay()));
                if (modeOrdinal < 3) {
                    modeOrdinal++; 
                } else  
                {
                    modeOrdinal = 0;
                }
            }
            if (command.equalsIgnoreCase("round") || command.equalsIgnoreCase("R")) {
                double out = Custom.round(Double.parseDouble(display.getDisplay()));
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("abs")) {
                double out = Custom.abs(Double.parseDouble(display.getDisplay()));
                Console.println(Double.toString(out));
                display.setDisplay(Double.toString(out));
            }
            if (command.equalsIgnoreCase("deg")) {
                    trigMode = 0;
                    Console.println("Trigonometric units are degrees");
            }
            if (command.equalsIgnoreCase("rad")) {
                    trigMode = 1;
                    Console.println("Trigonometric units are radians");
            }
            if (command.equalsIgnoreCase("trigSwitch")) {
                if (trigMode == 0) {
                    trigMode = 1;
                    Console.println("Trigonometric units are radians");
                } else  
                {
                    trigMode = 0;
                    Console.println("Trigonometric units are degrees");
                }
            }
            if (command.equalsIgnoreCase("sin")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Scientific.sine(first, trigMode);
                if (Double.toString(out) == "NaN") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("cos")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Scientific.cosine(first, trigMode);
                if (Double.toString(out) == "NaN") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("tan")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Scientific.tangent(first, trigMode);
                if (Double.toString(out) == "NaN") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("asin")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Scientific.inverseSin(first, trigMode);
                if (Double.toString(out) == "NaN") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("acos")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Scientific.inverseCosine(first, trigMode);
                if (Double.toString(out) == "NaN") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("atan")) {
                double first = Double.parseDouble(display.getDisplay());
                double out = Scientific.inverseTangent(first, trigMode);
                if (Double.toString(out) == "NaN") {
                    display.errorDisplay();
                } else {
                    Console.println(Double.toString(out));
                    display.setDisplay(Double.toString(out));
                }
            }
            if (command.equalsIgnoreCase("fact") || command.equalsIgnoreCase("x!")) {
                double first = Custom.round(Double.parseDouble(display.getDisplay()));
                BigInteger out = Scientific.factorial(first);
                Console.println(out.toString());
                display.setDisplay(out.toString());
            }
        }
    }
}