class Containers::CRBTreeMap

static VALUE rbtree_delete(VALUE self, VALUE key) {
        VALUE deleted_value;
        rbtree *tree = get_tree_from_self(self);
        if(!tree->root)
                return Qnil;
        
        tree->root = delete(tree, tree->root, key, &deleted_value);
        if(tree->root)
                tree->root->color = BLACK;
        
        if(deleted_value) {
                return deleted_value;
        }
                
        return Qnil;
}

static VALUE rbtree_delete_max(VALUE self) {
        VALUE deleted_value;
        rbtree *tree = get_tree_from_self(self);
        if(!tree->root)
                return Qnil;
        
        tree->root = delete_max(tree->root, &deleted_value);
        if(tree->root)
                tree->root->color = BLACK;
        
        if(deleted_value) {
                return deleted_value;
        }
                
        return Qnil;
}

static VALUE rbtree_delete_min(VALUE self) {
        VALUE deleted_value;
        rbtree *tree = get_tree_from_self(self);
        if(!tree->root)
                return Qnil;
        
        tree->root = delete_min(tree->root, &deleted_value);
        if(tree->root)
                tree->root->color = BLACK;
        
        if(deleted_value) {
                return deleted_value;
        }
                
        return Qnil;
}

static VALUE rbtree_each(VALUE self) {
        rbtree *tree = get_tree_from_self(self);
        rbt_each(tree, &rbtree_each_helper, NULL);
        return self;
}

static VALUE rbtree_is_empty(VALUE self) {
        rbtree *tree = get_tree_from_self(self);
        return (tree->root ? Qfalse : Qtrue);
}

static VALUE rbtree_get(VALUE self, VALUE key) {
        rbtree *tree = get_tree_from_self(self);
        return get(tree, tree->root, key);
}

static VALUE rbtree_has_key(VALUE self, VALUE key) {
        rbtree *tree = get_tree_from_self(self);
        if(!tree->root) { return Qfalse; }
        if(get(tree, tree->root, key) == Qnil)
                return Qfalse;
        
        return Qtrue;
}

static VALUE rbtree_height(VALUE self) {
        rbtree *tree = get_tree_from_self(self);
        return INT2NUM(height(tree->root));
}

static VALUE rbtree_max_key(VALUE self) {
        rbtree *tree = get_tree_from_self(self);
        if(!tree->root)
                return Qnil;
        
        return max_key(tree->root);
}

static VALUE rbtree_min_key(VALUE self) {
        rbtree *tree = get_tree_from_self(self);
        if(!tree->root)
                return Qnil;
        
        return min_key(tree->root);
}

static VALUE rbtree_push(VALUE self, VALUE key, VALUE value) {
        rbtree *tree = get_tree_from_self(self);
        tree->root = insert(tree, tree->root, key, value);
        return value;
}

static VALUE rbtree_size(VALUE self) {
        rbtree *tree = get_tree_from_self(self);
        return INT2NUM(size(tree->root));
}