Start of a JavaScript Binary Search Tree

BST.js

class BST {
  constructor(value) {
    this.root = new Node(value);
  }

  insert(value) {
    var recurse = function(node) {
      if (value < node.value) {
        node.left ? recurse(node.left) : node.left = new Node(value);
      } else {
        node.right ? recurse(node.right) : node.right = new Node(value);
      }
    }
    recurse(this.root)
  }

  contains(value) {
    var recurse = function(node) {
      if (node === null) {
        return false;
      }
      if (node.value === value) {
        return node;
      }
      if(value > node.value) {
        return recurse(node.right);
      } else if (value < node.value) {
        return recurse(node.left);
      }
    }
    return recurse(this.root);
  }

  _remove(value) {
    var recurse = function(node) {
      if (node === null) {
        return false;
      }
      if (node.value === value) {
        node = null;
        return true;
      }
      if(value > node.value) {
        return recurse(node.right);
      } else if (value < node.value) {
        return recurse(node.left);
      }
    }
    return recurse(this.root);
  }

  delete(value) {
    let nodeToDelete = this.contains(value);
    var parent
    if (!nodeToDelete) {
      return false;
    }

    //if no children
    if (!nodeToDelete.left && !nodeToDelete.right) {
      this._remove(nodeToDelete.value)
    } else if (nodeToDelete.left && nodeToDelete.right) {
      // find value of successor
      // go right, then go left untill no left child
      function rightThenLeft(node) {
        var current = node.right;
        while (current.left) {
          current = current.left;
        }
        return current;
      }
      var replacement = rightThenLeft(node)
      // set value of node to delete to successor
      // delete successor node

    } else {
      //1 kiddo
    }
  }

}

class Node {
  constructor(value) {
    this.value = value;
    this.left = null;
    this.right = null;
  }


}


         4
     0      5 --> change right child
  -1   3       ?10
     1  3.5   6     12
                11  13