#ifndef STATEMENT_CACHE_HPP
#define STATEMENT_CACHE_HPP

#include "matador/sql/executor.hpp"

#include "matador/sql/interface/statement_proxy.hpp"

#include <list>
#include <mutex>
#include <unordered_map>

namespace matador::sql {

class connection_pool;

class statement_cache final {
public:
  explicit statement_cache(connection_pool &pool, size_t max_size = 50);

  [[nodiscard]] utils::result<statement, utils::error> acquire(const query_context &ctx);

  [[nodiscard]] size_t size() const;
  [[nodiscard]] size_t capacity() const;
  [[nodiscard]] bool empty() const;

private:
  using list_iterator = std::list<size_t>::iterator;

  size_t max_size_{};
  std::list<size_t> usage_list_;  // LRU: front = most recent, back = least recent
  std::unordered_map<size_t, std::pair<statement, list_iterator>> cache_map_;
  std::mutex mutex_;

  connection_pool &pool_;
  const sql::dialect &dialect_;
};
}
#endif //STATEMENT_CACHE_HPP