#include <sstream>
#include <utility>

#include "absl/synchronization/mutex.h"
#include "tensorflow/c/experimental/filesystem/plugins/gcs/cleanup.h"

namespace tf_gcs_filesystem {

bool RamFileBlockCache::BlockNotStale(const std::shared_ptr<Block>& block) {
  absl::MutexLock l(&block->mu);
  if (block->state != FetchState::FINISHED) {
    return true;  // No need to check for staleness.
  }

  typedef std::map<Key, std::shared_ptr<Block>> BlockMap;

  /// Prune the cache by removing files with expired blocks.
  void Prune() ABSL_LOCKS_EXCLUDED(mu_);

  bool BlockNotStale(const std::shared_ptr<Block>& block)
      ABSL_EXCLUSIVE_LOCKS_REQUIRED(mu_);

  /// Look up a Key in the block cache.
  std::shared_ptr<Block> Lookup(const Key& key) ABSL_LOCKS_EXCLUDED(mu_);