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#ifndef IMPALA_RUNTIME_TEST_ENV
#define IMPALA_RUNTIME_TEST_ENV

#include "runtime/io/disk-io-mgr.h"
#include "runtime/exec-env.h"
#include "runtime/fragment-instance-state.h"
#include "runtime/mem-tracker.h"
#include "runtime/runtime-state.h"

namespace impala {

class QueryState;

/// Helper testing class that creates an environment with runtime memory management
/// similar to the one used by the Impala runtime. Only one TestEnv can be active at a
/// time, because it modifies the global ExecEnv singleton.
class TestEnv {
 public:
  TestEnv();
  ~TestEnv();

  /// Set custom configuration for TmpFileMgr. Only has effect if called before Init().
  /// If not called, the default configuration is used.
  void SetTmpFileMgrArgs(
      const std::vector<std::string>& tmp_dirs, bool one_dir_per_device);

  /// Disables creation of a BufferPool instance as part of this TestEnv in Init().
  void DisableBufferPool() { enable_buffer_pool_ = false; }

  /// Set configuration for BufferPool. Only has effect if called before Init().
  /// If not called, a buffer pool with no capacity is created.
  void SetBufferPoolArgs(int64_t min_buffer_len, int64_t capacity);

  /// Set configuration for the process memory tracker. Only has effect if called before
  /// Init(). If 'use_metrics' is true, the usual process memory tracker that uses
  /// memory consumption metrics is created, otherwise no metrics are used.
  /// If not called, a process memory tracker with no limit is created.
  void SetProcessMemTrackerArgs(int64_t bytes_limit, bool use_metrics);

  /// Initialize the TestEnv with the specified arguments.
  Status Init();

  /// Create a QueryState and a RuntimeState for a query with the given query options.
  /// The states are owned by the TestEnv. Returns an error if CreateQueryState() has
  /// been called with the same query ID already. 'runtime_state' is set to the newly
  /// created RuntimeState. The QueryState can be obtained via 'runtime_state'.
  Status CreateQueryState(
      int64_t query_id, const TQueryOptions* query_options, RuntimeState** runtime_state);

  /// Destroy all query states and associated RuntimeStates, etc, that were created since
  /// the last TearDownQueries() call.
  void TearDownQueries();

  /// Calculate memory limit accounting for overflow and negative values.
  /// If max_buffers is -1, no memory limit will apply.
  int64_t CalculateMemLimit(int max_buffers, int page_len);

  /// Return total of mem tracker consumption for all queries.
  int64_t TotalQueryMemoryConsumption();

  ExecEnv* exec_env() { return exec_env_.get(); }
  MetricGroup* metrics() { return exec_env_->metrics(); }
  TmpFileMgr* tmp_file_mgr() { return exec_env_->tmp_file_mgr(); }

 private:
  /// Recreate global metric groups.
  void InitMetrics();

  /// Arguments for TmpFileMgr, used in Init().
  bool have_tmp_file_mgr_args_;
  std::vector<std::string> tmp_dirs_;
  bool one_tmp_dir_per_device_;

  /// Whether a buffer pool should be created in Init().
  bool enable_buffer_pool_ = true;

  /// Arguments for BufferPool, used in Init().
  int64_t buffer_pool_min_buffer_len_;
  int64_t buffer_pool_capacity_;

  /// Arguments for process memory tracker, used in Init().
  int64_t process_mem_limit_ = -1;
  bool process_mem_tracker_use_metrics_ = false;

  /// Global state for test environment.
  static boost::scoped_ptr<MetricGroup> static_metrics_;
  boost::scoped_ptr<ExecEnv> exec_env_;

  /// Per-query states. TestEnv holds 1 refcount per QueryState in this map.
  std::vector<QueryState*> query_states_;

  /// One runtime state per query with an associated block manager. Each is owned
  /// by one of the 'query_states_'.
  std::vector<RuntimeState*> runtime_states_;
};
}

#endif