using System;
using System.Collections.Generic;
using System.Diagnostics;

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

namespace lab09_enumerate
{
    class Program
    {
        static void Main(string[] args)
        {
            Book b1 = new Book("A Bridge Too Near", "Bonnie", "Taylor", 2000);
            Book b2 = new Book("A Bridge Too Near 2", "Bonnie", "Taylor", 2002);
            Book b3 = new Book("A Bridge Too Near 3", "Bonnie", "Taylor", 2005);
            Book b4 = new Book("A Bridge Too Near: Even Nearer", "Bonnie", "Taylor", 2007);

            Node root = new Node(b1);
            root.Add(b2);
            root.Add(b3);
            root.Add(b4);

            foreach (Book b in root.GetBooks()) {
                if (b.Year > 2002) {
                    Console.WriteLine("({0}) {1}", b.Year, b.Title);
                }
            }
        }
    }

    class Book
    {
        public string Title { get; private set; }
        public string AuthorFirstName { get; private set; }
        public string AuthorLastName { get; private set; }
        public int Year { get; private set; }

        public Book(string title, string firstname,
            string lastname, int year)
        {
            Title = title;
            AuthorFirstName = firstname;
            AuthorLastName = lastname;
            Year = year;
        }

        public override string ToString()
        {
            return String.Format("{0}: {1}, {2} ({3})",
                Title,
                AuthorLastName,
                AuthorFirstName,
                Year);
        }
    }

    class Node
    {
        public Node Left { get; set; }
        public Node Right { get; set; }
        public Book Data { get; private set; }

        public void Add(Book b)
        {
            // if I have an open spot, add here
            if (Left == null) {
                Left = new Node(b);
                return;
            } else if (Right == null) {
                Right = new Node(b);
                return;
            }

            // otherwise, just add left (very unbalanced)
            Left.Add(b);
        }

        public void Print()
        {
            if (Left != null) Left.Print();
            Console.WriteLine(Data);
            if (Right != null) Right.Print();
        }

        public IEnumerable<Book> GetBooks()
        {
            if (Left != null)
                foreach (Book b in Left.GetBooks())
                    yield return b;

            yield return Data;

            if (Right != null)
                foreach (Book b in Right.GetBooks())
                    yield return b;
        }

        public Node(Book b) { Data = b; }
        public override string ToString() { return Data.ToString(); }
    }
}