package net.abhinavsarkar.algorist;

public class BinarySearchTree<K extends Comparable<K>,V>
{

    private Node<K,V> root;

    public BinarySearchTree() {
        this.root = null;
    }

    public void insert(K key, V val) {
        if (this.root == null) {
            this.root = new Node<>(key, val);
        } else {
            this.root.insert(key, val);
        }
    }

    public String toString() {
        return this.root.toString(0).toString();
    }

    public static class Node<K extends Comparable<K>,V> {
        private K key;
        private V val;
        private Node<K,V> left;
        private Node<K,V> right;

        public Node(K key, V val) {
            this.key = key;
            this.val = val;
        }
        public V getVal()
        {
            return val;
        }
        public K getKey()
        {
            return key;
        }

        public void insert(K key, V val)
        {
            if (this.key == key) {
                this.val = val;
            } else if (this.key.compareTo(key) > 0) {
                if (this.left == null) {
                    this.left = new Node<>(key, val);
                } else {
                    this.left.insert(key, val);
                }
            } else {
                if (this.right == null) {
                    this.right = new Node<>(key, val);
                } else {
                    this.right.insert(key, val);
                }
            }
        }

        public StringBuilder toString(int level) {
            StringBuilder sb = new StringBuilder()
                    .append(gutter(level))
                    .append("<" + key + ":" + val + ">\n");
            if (this.left != null) {
                sb.append(this.left.toString(level + 1));
            }
            if (this.right != null) {
                sb.append(this.right.toString(level + 1));
            }
            return sb;
        }

        private static StringBuilder gutter(int times) {
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < times; i++)
            {
                sb.append(' ');
            }
            return sb.append("|— ");
        }
    }

    public static void main(String[] args)
    {
        BinarySearchTree<String, String> bst = new BinarySearchTree<>();
        bst.insert("b", "barista");
        bst.insert("a", "abhinav");
        bst.insert("c", "carpool");
        bst.insert("d", "carl");

        System.out.println(bst);
    }

}