using System.Text;
using System.Text.RegularExpressions;

namespace opg1
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine($"AddAndMultiply: {AddAndMultiply(2, 4, 5)}");
            Console.WriteLine($"CToF(0): {CtoF(0)}");
            Console.WriteLine($"CToF(100): {CtoF(100)}");
            Console.WriteLine($"CToF(-300): {CtoF(-300)}");
            Console.WriteLine($"ElementaryOperations(3, 8): {string.Join(", ", ElementaryOperations(3, 8))}");
            Console.WriteLine($"IsResultTheSame(2+2, 2*2): {IsResultTheSame(2 + 2, 2 * 2)}");
            Console.WriteLine($"IsResultTheSame(9/3, 16-1): {IsResultTheSame(9 / 3, 16 - 1)}");
            Console.WriteLine($"ModuloOperations(8, 5, 2): {ModuloOperations(8, 5, 2)}");
            Console.WriteLine($"CubeOf(2): {CubeOf(2)}");
            Console.WriteLine($"CubeOf(-5.5): {CubeOf(-5.5)}");
            Console.WriteLine($"SwapTwoNumbers(87, 45): {string.Join(", ", SwapTwoNumbers(87, 45))}");
            Console.WriteLine($"SwapTwoNumbers(-13, 2): {string.Join(", ", SwapTwoNumbers(-13, 2))}");
            Console.WriteLine($"====== Conditional Statements ======");
            Console.WriteLine($"AbsoluteValue(6832): {AbsoluteValue(6832)}");
            Console.WriteLine($"AbsoluteValue(-392): {AbsoluteValue(-392)}");
            Console.WriteLine($"DivisibleBy2Or3(15, 30): {DivisibleBy2Or3(15, 30)}");
            Console.WriteLine($"DivisibleBy2Or3(2, 90): {DivisibleBy2Or3(2, 90)}");
            Console.WriteLine($"DivisibleBy2Or3(7, 12): {DivisibleBy2Or3(7, 12)}");
            Console.WriteLine($"IfConsistsOfUppercaseLetters('xyz'): {IfConsistsOfUppercaseLetters("xyz")}");
            Console.WriteLine($"IfConsistsOfUppercaseLetters('DOG'): {IfConsistsOfUppercaseLetters("DOG")}");
            Console.WriteLine($"IfConsistsOfUppercaseLetters('L9#'): {IfConsistsOfUppercaseLetters("L9#")}");
            Console.WriteLine($"IfGreaterThanThirdOne([2, 7, 12]) : {IfGreaterThanThirdOne([2, 7, 12])}");
            Console.WriteLine($"IfGreaterThanThirdOne([-5, -8, 50]): {IfGreaterThanThirdOne([-5, -8, 50])}");
            Console.WriteLine($"IfNumberIsEven(721): {IfNumberIsEven(721)}");
            Console.WriteLine($"IfNumberIsEven(1248): {IfNumberIsEven(1248)}");
            Console.WriteLine($"IfSortedAscending([3, 7, 10]): {IfSortedAscending([3, 7, 10])}");
            Console.WriteLine($"IfSortedAscending([74, 62, 99]): {IfSortedAscending([74, 62, 99])}");
            Console.WriteLine($"PositiveNegativeOrZero(5.24): {PositiveNegativeOrZero(5.24)}");
            Console.WriteLine($"PositiveNegativeOrZero(0.0): {PositiveNegativeOrZero(0.0)}");
            Console.WriteLine($"PositiveNegativeOrZero(-994.53): {PositiveNegativeOrZero(-994.53)}");
            Console.WriteLine($"IfYearIsLeap(2016): {IfYearIsLeap(2016)}");
            Console.WriteLine($"IfYearIsLeap(2018): {IfYearIsLeap(2018)}");
        }

        static int AddAndMultiply(int a, int b, int c)
        {
            return (a + b) * c;
        }

        static string CtoF(int celcius)
        {
            if (celcius <= -271.15)
                return "Temperature below absolute zero!";

            double fahrenheit = (celcius * 1.8) + 32;

            return $"T = {fahrenheit}F";
        }

        static List<double> ElementaryOperations(double a, double b)
        {
            List<double> retval = [a + b, a - b, a * b];
            if (a > 0 && b > 0)
                retval.Add(a / b);

            return retval;
        }

        static bool IsResultTheSame(double a, double b)
        {
            return a == b;
        }

        static int ModuloOperations(int a, int b, int c)
        {
            return (a % b) % c;
        }

        static double CubeOf(double a)
        {
            return a * a * a;
        }

        static List<int> SwapTwoNumbers(int a, int b)
        {
            return [b, a];
        }

        static int AbsoluteValue(int a)
        {
            return Math.Abs(a);
        }

        static int DivisibleBy2Or3(int a, int b)
        {
            if (_DivisibleBy2Or3(a) && _DivisibleBy2Or3(b))
            {
                return a * b;
            }


            static bool _DivisibleBy2Or3(int x)
            {
                return (x % 3) == 0 || (x % 2) == 0;
            }

            return a + b;
        }

        static bool IfConsistsOfUppercaseLetters(string str)
        {
            return str.Equals(Regex.Match(str, "[A-Z]+").Value);
        }

        static bool IfGreaterThanThirdOne(List<int> ints)
        {
            if (ints.Count < 3)
            {
                throw new Exception("Must have 3 or more ints");
            }

            return (ints[0] * ints[1]) > ints[2];
        }

        static bool IfNumberIsEven(int a)
        {
            return a % 2 == 0;
        }

        static bool IfSortedAscending(List<int> ints)
        {
            int lastNumber = 0;
            bool retval = true;

            ints.ForEach(x =>
            {
                if (lastNumber < x)
                {
                    lastNumber = x;
                }
                else
                {
                    retval = false;
                }
            });

            return retval;
        }

        static string PositiveNegativeOrZero(double a)
        {
            switch (a)
            {
                case > 0:
                    return "positive";
                case < 0:
                    return "negative";
                default:
                    return "zero";
            }
        }

        static bool IfYearIsLeap(int year)
        {
            return DateTime.IsLeapYear(year);
        }
    }
}