using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace samm2
{
    class QueuingSystem
    {
        private double _lambda, _mu;
        private Random _random;
        private double tempTimeInput = 0;
        private double tempTimeFirst = 0;
        private double tempTimeSecond = 0;
        private Calculator calculator = new Calculator();
        private double inputTime = 0;
        private double outputTime = 0;
        private double firstStageTime = 0;
        private double secondStageTime = 0;
        private double tempMuGl = 0;
        private List<double> times = new List<double>();
        private int[] t = new int[3];

        private int inputStep = 1;
        private int outputStep = 0;
        private int queueCounter = 0;

        public QueuingSystem(double lambda, double mu)
        {
            _lambda = lambda;
            _mu = 2 * mu;
            _random = new Random();
            inputTime = getTime(_lambda);
            outputTime = getTime(_mu);
        }

        public double Lambda { get => _lambda; }
        public double Mu { get => _mu; }

        public string Imitate(int numberTacts)
        {
            calculator.Clear();

            for (double i = 0; i < numberTacts; i += 0.01)
            {
                GetNextState(i);
            }

            var a = calculator.getA(numberTacts);
            var l = calculator.getL(numberTacts);

            return "A = " + a.ToString() + ";\r\n Lоч = " + l.ToString() + ";";
        }

        private double getTime(double intensity)
        {
            return (double)((-1 / intensity) * Math.Log(_random.NextDouble()));
        }

        private void GetNextState(double currentTime)
        {
            if (inputTime <= currentTime)
            {
                inputTime = getTime(_lambda) + currentTime;
                if (inputStep == 4)
                {
                    inputStep = 1;

                    if (outputStep == 0) // not processes
                    {
                        outputStep = 1;
                        outputTime = getTime(_mu) + currentTime;
                    }
                    else
                    {
                        queueCounter++;
                    }
                }
                else // inputStep = 1..3
                {
                    inputStep++;
                }
            }
            if (outputTime <= currentTime && outputStep != 0)
            {
                if (outputStep == 3)
                {

                    if (queueCounter > 0)
                    {
                        outputTime = getTime(_mu) + currentTime;
                        outputStep = 1;
                        queueCounter--;
                    }
                    else
                    {
                        outputStep = 0;
                    }
                }
                else // outputStep = 1..2
                {
                    outputTime = getTime(_mu) + currentTime;
                    outputStep++;
                }
            }
        }
    }
}