/*

Stockfish, a UCI chess playing engine derived from Glaurung 2.1

Copyright (C) 2004-2008 Tord Romstad (Glaurung author)

Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad

Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad

Stockfish is free software: you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation, either version 3 of the License, or

(at your option) any later version.

Stockfish is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program. If not, see <http://www.gnu.org/licenses/>.

*/

#ifndef THREAD_H_INCLUDED

#define THREAD_H_INCLUDED

#include <atomic>

#include <bitset>

#include <condition_variable>

#include <mutex>

#include <thread>

#include <vector>

#include "material.h"

#include "movepick.h"

#include "pawns.h"

#include "position.h"

#include "search.h"

#include "thread_win32.h"

/// Thread struct keeps together all the thread-related stuff. We also use

/// per-thread pawn and material hash tables so that once we get a pointer to an

/// entry its life time is unlimited and we don't have to care about someone

/// changing the entry under our feet.

class Thread {

std::thread nativeThread;

Mutex mutex;

ConditionVariable sleepCondition;

bool exit, searching;

public:

Thread();

virtual ~Thread();

virtual void search();

void idle_loop();

void start_searching(bool resume = false);

void wait_for_search_finished();

void wait(std::atomic_bool& b);

Pawns::Table pawnsTable;

Material::Table materialTable;

Endgames endgames;

size_t idx, PVIdx;

int maxPly, callsCnt;

uint64_t tbHits;

Position rootPos;

Search::RootMoves rootMoves;

Depth rootDepth;

Depth completedDepth;

std::atomic_bool resetCalls;

HistoryStats history;

MoveStats counterMoves;

FromToStats fromTo;

CounterMoveHistoryStats counterMoveHistory;

};

/// MainThread is a derived class with a specific overload for the main thread

struct MainThread : public Thread {

virtual void search();

bool easyMovePlayed, failedLow;

double bestMoveChanges;

Value previousScore;

};

/// ThreadPool struct handles all the threads-related stuff like init, starting,

/// parking and, most importantly, launching a thread. All the access to threads

/// data is done through this class.

struct ThreadPool : public std::vector<Thread*> {

void init(); // No constructor and destructor, threads rely on globals that should

void exit(); // be initialized and valid during the whole thread lifetime.

MainThread* main() { return static_cast<MainThread*>(at(0)); }

void start_thinking(Position&, StateListPtr&, const Search::LimitsType&);

void read_uci_options();

uint64_t nodes_searched() const;

uint64_t tb_hits() const;

private:

StateListPtr setupStates;

};

extern ThreadPool Threads;

#endif // #ifndef THREAD_H_INCLUDED