/*
 * Kyle Pierce
 * CSE 143
 *
 * This class represents a generic binary search tree
 */
public class SearchTree<E extends Comparable<E>> {
   private TreeNode<E> overallRoot;

   // post: constructs an empty tree
   public SearchTree() {
      overallRoot = null; 
   }

   // pre:  tree is a binary search tree
   // post: value added to overall tree to preserve
   //       binary search tree property
   public void add(E value) {
      overallRoot = add(overallRoot, value);
   }

   // pre:  tree is a binary search tree
   // post: value added to tree with given root to preserve
   //       binary search tree property
   public TreeNode<E> add(TreeNode<E> root, E value) {
      if (root == null) {
         root = new TreeNode<E>(value);
      } else if (value.compareTo(root.data) < 0) {
         root.left = add(root.left, value);
      } else if (value.compareTo(root.data) > 0) {
         root.right = add(root.right, value);
      }
      return root;
   }

   // pre:  tree is a binary search tree
   // post: returns true if the given value is in the tree, false otherwise
   public boolean contains(E value) {
      return contains(overallRoot, value);
   }

   // pre:  tree is a binary search tree
   // post: returns true if the given value is in given tree, false otherwise
   private boolean contains(TreeNode<E> root, E value) {
      if (root == null) {
         return false;
      } else if (root.data.equals(value)) {
         return true;
      } else if (root.data.compareTo(value) < 0) {
         return contains(root.left, value);
      } else {
         return contains(root.right, value);
      }
   }

   // post: returns a String representation of the tree
   public String toString() {
      String s = toString(overallRoot);
      return "[" + s.substring(0, s.length() - 2) + "]";
   }

   // post: returns a String representation of the given tree
   private String toString(TreeNode<E> root) {
      if (root == null) {
         return "";
      } else {
         return toString(root.left) + 
                root.data + ", " +
                toString(root.right);
      }
   }
}