#include <sstream>

#include "vfs.h"

/* Create a new node. */
vfs_node* new_node(std::string name, vfs_node_type type, vfs_node* parent) {
  vfs_node* node  = new vfs_node();
  node->name      = name;
  node->type      = type;
  node->parent    = parent;
  return node;
}

std::string get_full_path(vfs_node* node) {
  if(node->parent == nullptr) {
    return "/";
  }
  if(node->parent->parent == nullptr) { /* If parent is root. */
    return "/" + node->name;
  }
  return get_full_path(node->parent) + "/" + node->name;
}

void delete_vfs_tree(vfs_node* node) {
  if(!node) {
    return;
  }

  if(node->type == DIR_NODE) {
    for(auto const& [key, val] : node->children) {
      delete_vfs_tree(val);
    }
  }
  delete node;
}

/* Find a VFS node by it's absolute path. */
vfs_node* find_node_by_path(vfs_node* root, const std::string& path) {
  if(path == "/") {
    return root;
  }
  vfs_node* current = root;
  std::stringstream ss(path);
  std::string segment;

  /* Discard the first empty segment that comes form the leading '/'. */
  if(path[0] == '/') {
    std::getline(ss, segment, '/');
  }

  while(std::getline(ss, segment, '/')) {
    if(current->type == DIR_NODE && current->children.count(segment)) {
      current = current->children[segment];
    } else {
      return nullptr; /* Path segmenet not found. */
    }
  }
  return current;
}