#ifndef MATADOR_BASIC_REPOSITORY_HPP
#define MATADOR_BASIC_REPOSITORY_HPP

#include "matador/object/error_code.hpp"
#include "matador/object/object_info.hpp"
#include "matador/object/repository_node_iterator.hpp"

#include "matador/logger/logger.hpp"

#include "matador/utils/error.hpp"
#include "matador/utils/result.hpp"

#include <typeindex>
#include <unordered_map>

namespace matador::object {
utils::error make_error(error_code ec, const std::string &msg);

class repository_node;
class const_repository_node_iterator;

class basic_repository {
public:
  typedef const_repository_node_iterator const_iterator; /**< Shortcut for the list const iterator. */

  explicit basic_repository(std::string name = "");
  ~basic_repository();

  /**
   *
   * @param node Node to attach
   * @param parent Name of parent node
   * @return Attached node
   */
  [[nodiscard]] utils::result<repository_node*, utils::error> attach_node(repository_node *node, const std::string &parent);

  /**
   * Detaches a given node from the schema. If the
   * node is a parent of other nodes, these nodes  are
   * detached as well.
   *
   * @param node Node to detach from schema
   * @return Result object indicating success or failure
   */
  [[nodiscard]] utils::result<void, utils::error> detach(repository_node *node);

  /**
   * Return the first schema node.
   *
   * @return The first schema node iterator.
   */
  [[nodiscard]] const_iterator begin() const;

  /**
   * Return the last schema node.
   *
   * @return The last schema node iterator.
   */
  [[nodiscard]] const_iterator end() const;

  /**
   * Returns true if the schema contains
   * no schema nodes.
   *
   * @return True if the schema is empty
   */
  [[nodiscard]] bool empty() const;

  /**
   * Returns the current number of the schema node.
   *
   * @return Number of schema nodes
   */
  [[nodiscard]] size_t size() const;

  /**
   * Returns the name of the schema.
   *
   * @return The name of the schema
   */
  [[nodiscard]] std::string name() const;

  [[nodiscard]] bool contains(const std::string &name) const;
  [[nodiscard]] bool contains(const std::type_index &index) const;
  template < typename Type >
  [[nodiscard]] bool contains() const {
    return contains(std::type_index(typeid(Type)));
  }


  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::type_index& ti) const;
  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info(const std::string &name) const;
  template<typename Type>
  [[nodiscard]] utils::result<basic_object_info_ref, utils::error> basic_info() const {
    return basic_info(std::type_index(typeid(Type)));
  }

  [[nodiscard]] utils::result<attribute*, utils::error> primary_key_attribute(const std::type_index &ti) const;

  void dump(std::ostream &os) const;
  static void dump(std::ostream &os, const repository_node& node);

protected:
  using t_node_map = std::unordered_map<std::string, repository_node*>;
  using t_type_index_node_map = std::unordered_map<std::type_index, repository_node*>;

protected:
  [[nodiscard]] const_iterator find_node(const std::string &name) const;
  [[nodiscard]] const_iterator find_node(const std::type_index &type_index) const;
  template<typename Type>
  [[nodiscard]] const_iterator find_node() const {
    return find_node(std::type_index(typeid(Type)));
  }

  [[nodiscard]] bool has_node(const std::string &name) const;
  [[nodiscard]] bool has_node(const std::type_index &index) const;
  [[nodiscard]] bool has_node(const repository_node* node) const;

  static void insert_node(repository_node *parent, repository_node *child);
  void remove_node(repository_node *node);

  [[nodiscard]] bool expecting_relation_node(const std::string &name) const;
  void expect_relation_node(const std::string &name, const std::type_index &ti);
  void remove_expected_relation_node(const std::string &name);

  [[nodiscard]] std::shared_ptr<object> provide_object_in_advance(const std::type_index &ti, const std::shared_ptr<object>& obj);
  [[nodiscard]] bool has_object_for_type(const std::type_index &ti) const;
  [[nodiscard]] std::shared_ptr<object> object_for_type(const std::type_index &ti) const;
  void remove_object_for_type(const std::type_index &ti);

  [[nodiscard]] bool is_node_announced(const std::type_index &ti) const;
  void push_announce_node(const std::type_index &ti, std::unique_ptr<repository_node> &&node);
  [[nodiscard]] repository_node* announce_node(const std::type_index &ti) const;
  [[nodiscard]] std::unique_ptr<repository_node> pop_announce_node(const std::type_index &ti);

protected:
  friend class object_generator;
  template < typename NodeType, template<typename> typename ...Observers >
  friend class foreign_node_completer;
  template < typename NodeType, template<typename> typename ...Observers >
  friend class relation_completer;

  std::string name_;
  repository_node* root_{nullptr};

  t_node_map nodes_by_name_;
  t_type_index_node_map nodes_by_type_;
  logger::logger log_;

  std::unordered_map<std::type_index, std::unique_ptr<repository_node>> announced_node_;
  std::unordered_map<std::type_index, attribute*> missing_references_{};
  std::unordered_map<std::string, std::type_index> expected_relation_nodes_;
  std::unordered_map<std::type_index, std::shared_ptr<object>> object_by_type_{};
};
}
#endif //MATADOR_BASIC_REPOSITORY_HPP