//static private List<InstructorExample> AllInstructors = new List<InstructorExample>();

        public Lesson(int id, string title, Instructor instructor, Chapter chapter,Double diff_fac)
        {
            this.Id = id;
            this.Title = title;
            this.Instructor = instructor;
            this.difficultyfactor = diff_fac;
            this.Chapter = chapter;
            this.totalPlayTime = 0;
            this.playedTime = 0;

        }
 public Lesson(string title, Instructor instructor, Chapter chapter, string videopath, long sizeInBytes, DateTime lastPlayed)
 {
     this.Title = title;
     this.Instructor = instructor;
     this.LastPlayed = lastPlayed;
     this.SizeInBytes = sizeInBytes;
     this.Chapter = chapter;
     this.videoPath = videopath;
     this.totalPlayTime = 0;
     this.playedTime = 0;
     this.isFinished = false;
 }
        public static List<Lesson> InitializeLessons()
        {
            List<Lesson> lessons = new List<Lesson>();
            Chapter ch1 = new Chapter("Matrices", 1);
            Chapter ch2 = new Chapter("Kinametics", 2);
            Chapter ch3 = new Chapter("Dynamics", 3);
            Chapter ch4 = new Chapter("Turning Effect of Force", 4);
            Chapter ch5 = new Chapter("Gravitation", 5);
            Chapter ch6 = new Chapter("Work and Energy", 6);
            Chapter ch7 = new Chapter("Properties of Matter", 7);
            Chapter ch8 = new Chapter("Thermal Properties of Matter", 8);
            Chapter ch9 = new Chapter("Transfer of Heat", 9);
            Instructor ph = new Instructor("Dr.Pervaiz HoodBhoy");


            lessons.Add(new Lesson(1, "1.Definition of Matrix", ph, ch1,0.8));
            lessons.Add(new Lesson(2, "2.Order of Matrix", ph, ch1, 0.8));
            lessons.Add(new Lesson(3, "3.Row Matrix and Coloumn Matrix", ph, ch1,0.6));
            lessons.Add(new Lesson(4, "4.Square and Rectangular Matrices", ph, ch1,0.8));
            lessons.Add(new Lesson(5, "5.Null or Zero Matrix", ph, ch1,0.8));
            lessons.Add(new Lesson(6, "6.Transpose of a Matrix", ph, ch1,0.7));
            lessons.Add(new Lesson(7, "7.Negative of a Matrix", ph, ch1, 0.6));
            lessons.Add(new Lesson(8, "8.Symmetric and Skew-symmetric Matrices", ph, ch1,0.7));
            lessons.Add(new Lesson(9, "9.Diagonal Matrix", ph, ch1, 0.4));
            lessons.Add(new Lesson(10, "10.Scalar Matrix", ph, ch1,0.5));
            lessons.Add(new Lesson(11, "11.Identity Matrix", ph, ch1, 0.4));
            lessons.Add(new Lesson(12, "12.Addition of Matrices", ph, ch1, 0.4));
            lessons.Add(new Lesson(13, "13.Subtraction of Matrices", ph, ch1,0.5));
            lessons.Add(new Lesson(14, "14.Multiplication of a Matrix by a Real number", ph, ch1, 0.5));
            lessons.Add(new Lesson(15, "15.Commutative Law under Addition of Matrices", ph, ch1, 0.3));
            lessons.Add(new Lesson(16, "16.Associative Law under Addition of Matrices", ph, ch1, 0.5));
            lessons.Add(new Lesson(17, "17.Additive Identity of a Matrix", ph, ch1, 0.3));
            lessons.Add(new Lesson(18, "18.Additive Inverse of a Matrix", ph, ch1,0.34));
            lessons.Add(new Lesson(19, "19.Multiplication of Matrices", ph, ch1, 0.4));
            lessons.Add(new Lesson(20, "20.Associative Law under Multiplication of Matrices", ph, ch1,0.35));
            lessons.Add(new Lesson(21, "21.Distributive Law of Multiplication over Addition for Matrices", ph, ch1, 0.54));
            lessons.Add(new Lesson(22, "22.Commutative Law of Multiplication of Matrices for Matrices", ph, ch1,0.2));

            lessons.Add(new Lesson(1, "Rest and Motion", ph, ch2, 0.2));
            lessons.Add(new Lesson(2, "Types of Motion", ph, ch2, 0.2));
            lessons.Add(new Lesson(3, "Terms associated with Motion", ph, ch2, 0.2));
            lessons.Add(new Lesson(4, "Scalars and Vectors", ph, ch2, 0.2));
            lessons.Add(new Lesson(5, "Graphical Analysis of Motion", ph, ch2, 0.2));
            lessons.Add(new Lesson(6, "Equations of Motions", ph, ch2, 0.2));
            lessons.Add(new Lesson(7, "Motion due to Gravity", ph, ch2, 0.2));

            lessons.Add(new Lesson(1, "Momentum", ph, ch3, 0.2));
            lessons.Add(new Lesson(2, "Newtons laws of motion", ph, ch3, 0.2));
            lessons.Add(new Lesson(3, "Friction", ph, ch3, 0.2));
            lessons.Add(new Lesson(4, "Uniform Circular Motion", ph, ch3, 0.2));

            lessons.Add(new Lesson(1, "Forces on Bodies", ph, ch4, 0.2));
            lessons.Add(new Lesson(2, "Addition of Forces", ph, ch4, 0.2));
            lessons.Add(new Lesson(3, "Resolution of Forces", ph, ch4, 0.2));
            lessons.Add(new Lesson(4, "Momentum of a Force", ph, ch4, 0.2));
            lessons.Add(new Lesson(5, "Principle of Moments", ph, ch4, 0.2));
            lessons.Add(new Lesson(6, "Center of Mass", ph, ch4, 0.2));
            lessons.Add(new Lesson(7, "Couple", ph, ch4, 0.2));
            lessons.Add(new Lesson(8, "Couple", ph, ch4, 0.2));
            lessons.Add(new Lesson(9, "Stability", ph, ch4, 0.2));

            lessons.Add(new Lesson(1, "Law of Gravitation", ph, ch5, 0.2));
            lessons.Add(new Lesson(2, "Measurment of mass of Erth", ph, ch5, 0.2));
            lessons.Add(new Lesson(3, "Variation of g with Altitude", ph, ch5, 0.2));
            lessons.Add(new Lesson(4, "Motion of Artificial satellites", ph, ch5, 0.2));

            lessons.Add(new Lesson(1, "Work", ph, ch6, 0.2));
            lessons.Add(new Lesson(2, "Energy", ph, ch6, 0.2));
            lessons.Add(new Lesson(3, "Kinetic Energy", ph, ch6, 0.2));
            lessons.Add(new Lesson(4, "Potential Energy", ph, ch6, 0.2));
            lessons.Add(new Lesson(5, "Forms of Energy", ph, ch6, 0.2));
            lessons.Add(new Lesson(6, "Interconversion of Energy", ph, ch6, 0.2));
            lessons.Add(new Lesson(7, "Major sources of Energy", ph, ch6, 0.2));
            lessons.Add(new Lesson(8, "Effiency", ph, ch6, 0.2));
            lessons.Add(new Lesson(9, "Power", ph, ch6, 0.2));

            lessons.Add(new Lesson(1, "Kinetic Molecular Model of Matter", ph, ch7, 0.2));
            lessons.Add(new Lesson(2, "Density", ph, ch7, 0.2));
            lessons.Add(new Lesson(3, "Pressure", ph, ch7, 0.2));
            lessons.Add(new Lesson(4, "Atmosphere Pressure", ph, ch7, 0.2));
            lessons.Add(new Lesson(5, "Pressure in Liquids", ph, ch7, 0.2));
            lessons.Add(new Lesson(6, "Upthrust", ph, ch7, 0.2));
            lessons.Add(new Lesson(7, "Principle of Floatation", ph, ch7, 0.2));
            lessons.Add(new Lesson(8, "Elasticity", ph, ch7, 0.2));
            lessons.Add(new Lesson(9, "Stress, Strain and Young Modulus", ph, ch7, 0.2));

            lessons.Add(new Lesson(1, "Temperature and Heat", ph, ch8, 0.2));
            lessons.Add(new Lesson(2, "Thermometer", ph, ch8, 0.2));
            lessons.Add(new Lesson(3, "Specific Heat Capacity", ph, ch8, 0.2));
            lessons.Add(new Lesson(4, "Latent heat of Fusion", ph, ch8, 0.2));
            lessons.Add(new Lesson(5, "Latent Heat of Vaporization", ph, ch8, 0.2));
            lessons.Add(new Lesson(6, "Evaporation", ph, ch8, 0.2));
            lessons.Add(new Lesson(7, "Thermal Expansion", ph, ch8, 0.2));

            lessons.Add(new Lesson(1, "The Three Processes of Heat Transfer", ph, ch9, 0.2));
            lessons.Add(new Lesson(2, "Conduction", ph, ch9, 0.2));
            lessons.Add(new Lesson(3, "Convection", ph, ch9, 0.2));
            lessons.Add(new Lesson(4, "Radiation", ph, ch9, 0.2));
            lessons.Add(new Lesson(5, "Consequences and everyday\nApplications of Heat Transfer", ph, ch9, 0.2));

            int i = 0;
            foreach (Lesson s in lessons)
            {
                s.VideoPath = getVideoPath(i);
                i++;
                //s.VideoPath = @"C:\videos\1.mp4";
                s.getQuizes();
                Console.WriteLine(s.VideoPath);
            }

            Controller.selectedLesson = lessons.ElementAt(0);

            return lessons;
        }