#include "avl.h"
#include "avl-private.h"

// Perform a shallow copy of src, return the
// new tree in ret
forall(K | Comparable(K), V)
int copy(tree(K, V) * src, tree(K, V) ** ret){
  tree(K, V) * helper(tree(K, V) * t, int * worked){
    if (empty(t)){
      // given empty tree, return empty tree
      return NULL;
    }

    // otherwise, this is not an empty node,
    // create a new node
    tree(K, V) * newTree = create(t->key, t->value);
    if (empty(newTree)) {
      *worked = 1;
      return NULL;
    }

    // recursively copy the left and right branches
    newTree->left = helper(t->left, worked);
    newTree->right = helper(t->right, worked);

    setParent(newTree->left, newTree);
    setParent(newTree->right, newTree);
    return newTree;
  }

  int worked = 0;
  *ret = helper(src, &worked);
  return worked;
}

// Apply func to every value element in t, using an in order traversal
forall(K | Comparable(K), V)
void for_each(tree(K, V) * t, int (*func)(V)) {
  if (t == NULL) {
    return;
  }
  // recursively apply the function to the left,
  // apply the function to this node,
  // recursively apply the function to the right
  for_each(t->left, func);
  func(t->value);
  for_each(t->right, func);
}