data

/*
Minetest
Copyright (C) 2010-2017 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "serverenvironment.h"
#include "content_sao.h"
#include "settings.h"
#include "log.h"
#include "mapblock.h"
#include "nodedef.h"
#include "nodemetadata.h"
#include "gamedef.h"
#include "map.h"
#include "porting.h"
#include "profiler.h"
#include "raycast.h"
#include "remoteplayer.h"
#include "scripting_server.h"
#include "server.h"
#include "util/serialize.h"
#include "util/basic_macros.h"
#include "util/pointedthing.h"
#include "threading/mutex_auto_lock.h"
#include "filesys.h"
#include "gameparams.h"
#include "database/database-dummy.h"
#include "database/database-files.h"
#include "database/database-sqlite3.h"
#if USE_POSTGRESQL
#include "database/database-postgresql.h"
#endif
#include <algorithm>

#define LBM_NAME_ALLOWED_CHARS "abcdefghijklmnopqrstuvwxyz0123456789_:"

// A number that is much smaller than the timeout for particle spawners should/could ever be
#define PARTICLE_SPAWNER_NO_EXPIRY -1024.f

/*
	ABMWithState
*/

ABMWithState::ABMWithState(ActiveBlockModifier *abm_):
	abm(abm_)
{
	// Initialize timer to random value to spread processing
	float itv = abm->getTriggerInterval();
	itv = MYMAX(0.001, itv); // No less than 1ms
	int minval = MYMAX(-0.51*itv, -60); // Clamp to
	int maxval = MYMIN(0.51*itv, 60);   // +-60 seconds
	timer = myrand_range(minval, maxval);
}

/*
	LBMManager
*/

void LBMContentMapping::deleteContents()
{
	for (auto &it : lbm_list) {
		delete it;
	}
}

void LBMContentMapping::addLBM(LoadingBlockModifierDef *lbm_def, IGameDef *gamedef)
{
	// Add the lbm_def to the LBMContentMapping.
	// Unknown names get added to the global NameIdMapping.
	const NodeDefManager *nodedef = gamedef->ndef();

	lbm_list.push_back(lbm_def);

	for (const std::string &nodeTrigger: lbm_def->trigger_contents) {
		std::vector<content_t> c_ids;
		bool found = nodedef->getIds(nodeTrigger, c_ids);
		if (!found) {
			content_t c_id = gamedef->allocateUnknownNodeId(nodeTrigger);
			if (c_id == CONTENT_IGNORE) {
				// Seems it can't be allocated.
				warningstream << "Could not internalize node name \"" << nodeTrigger
					<< "\" while loading LBM \"" << lbm_def->name << "\"." << std::endl;
				continue;
			}
			c_ids.push_back(c_id);
		}

		for (content_t c_id : c_ids) {
			map[c_id].push_back(lbm_def);
		}
	}
}

const std::vector<LoadingBlockModifierDef *> *
LBMContentMapping::lookup(content_t c) const
{
	lbm_map::const_iterator it = map.find(c);
	if (it == map.end())
		return NULL;
	// This first dereferences the iterator, returning
	// a std::vector<LoadingBlockModifierDef *>
	// reference, then we convert it to a pointer.
	return &(it->second);
}

LBMManager::~LBMManager()
{
	for (auto &m_lbm_def : m_lbm_defs) {
		delete m_lbm_def.second;
	}

	for (auto &it : m_lbm_lookup) {
		(it.second).deleteContents();
	}
}

void LBMManager::addLBMDef(LoadingBlockModifierDef *lbm_def)
{
	// Precondition, in query mode the map isn't used anymore
	FATAL_ERROR_IF(m_query_mode,
		"attempted to modify LBMManager in query mode");

	if (!string_allowed(lbm_def->name, LBM_NAME_ALLOWED_CHARS)) {
		throw ModError("Error adding LBM \"" + lbm_def->name +
			"\": Does not follow naming conventions: "
				"Only characters [a-z0-9_:] are allowed.");
	}

	m_lbm_defs[lbm_def->name] = lbm_def;
}

void LBMManager::loadIntroductionTimes(const std::string &times,
	IGameDef *gamedef, u32 now)
{
	m_query_mode = true;

	// name -> time map.
	// Storing it in a map first instead of
	// handling the stuff directly in the loop
	// removes all duplicate entries.
	// TODO make this std::unordered_map
	std::map<std::string, u32> introduction_times;

	/*
	The introduction times string consists of name~time entries,
	with each entry terminated by a semicolon. The time is decimal.
	 */

	size_t idx = 0;
	size_t idx_new;
	while ((idx_new = times.find(';', idx)) != std::string::npos) {
		std::string entry = times.substr(idx, idx_new - idx);
		std::vector<std::string> components = str_split(entry, '~');
		if (components.size() != 2)
			throw SerializationError("Introduction times entry \""
				+ entry + "\" requires exactly one '~'!");
		const std::string &name = components[0];
		u32 time = from_string<u32>(components[1]);
		introduction_times[name] = time;
		idx = idx_new + 1;
	}

	// Put stuff from introduction_times into m_lbm_lookup
	for (std::map<std::string, u32>::const_iterator it = introduction_times.begin();
		it != introduction_times.end(); ++it) {
		const std::string &name = it->first;
		u32 time = it->second;

		std::map<std::string, LoadingBlockModifierDef *>::iterator def_it =
			m_lbm_defs.find(name);
		if (def_it == m_lbm_defs.end()) {
			// This seems to be an LBM entry for
			// an LBM we haven't loaded. Discard it.
			continue;
		}
		LoadingBlockModifierDef *lbm_def = def_it->second;
		if (lbm_def->run_at_every_load) {
			// This seems to be an LBM entry for
			// an LBM that runs at every load.
			// Don't add it just yet.
			continue;
		}

		m_lbm_lookup[time].addLBM(lbm_def, gamedef);

		// Erase the entry so that we know later
		// what elements didn't get put into m_lbm_lookup
		m_lbm_defs.erase(name);
	}

	// Now also add the elements from m_lbm_defs to m_lbm_lookup
	// that weren't added in the previous step.
	// They are introduced first time to this world,
	// or are run at every load (introducement time hardcoded to U32_MAX).

	LBMContentMapping &lbms_we_introduce_now = m_lbm_lookup[now];
	LBMContentMapping &lbms_running_always = m_lbm_lookup[U32_MAX];

	for (auto &m_lbm_def : m_lbm_defs) {
		if (m_lbm_def.second->run_at_every_load) {
			lbms_running_always.addLBM(m_lbm_def.second, gamedef);
		} else {
			lbms_we_introduce_now.addLBM(m_lbm_def.second, gamedef);
		}
	}

	// Clear the list, so that we don't delete remaining elements
	// twice in the destructor
	m_lbm_defs.clear();
}

std::string LBMManager::createIntroductionTimesString()
{
	// Precondition, we must be in query mode
	FATAL_ERROR_IF(!m_query_mode,
		"attempted to query on non fully set up LBMManager");

	std::ostringstream oss;
	for (const auto &it : m_lbm_lookup) {
		u32 time = it.first;
		const std::vector<LoadingBlockModifierDef *> &lbm_list = it.second.lbm_list;
		for (const auto &lbm_def : lbm_list) {
			// Don't add if the LBM runs at every load,
			// then introducement time is hardcoded
			// and doesn't need to be stored
			if (lbm_def->run_at_every_load)
				continue;
			oss << lbm_def->name << "~" << time << ";";
		}
	}
	return oss.str();
}

void LBMManager::applyLBMs(ServerEnvironment *env, MapBlock *block, u32 stamp)
{
	// Precondition, we need m_lbm_lookup to be initialized
	FATAL_ERROR_IF(!m_query_mode,
		"attempted to query on non fully set up LBMManager");
	v3s16 pos_of_block = block->getPosRelative();
	v3s16 pos;
	MapNode n;
	content_t c;
	lbm_lookup_map::const_iterator it = getLBMsIntroducedAfter(stamp);
	for (; it != m_lbm_lookup.end(); ++it) {
		// Cache previous version to speedup lookup which has a very high performance
		// penalty on each call
		content_t previous_c{};
		std::vector<LoadingBlockModifierDef *> *lbm_list = nullptr;

		for (pos.X = 0; pos.X < MAP_BLOCKSIZE; pos.X++)
			for (pos.Y = 0; pos.Y < MAP_BLOCKSIZE; pos.Y++)
				for (pos.Z = 0; pos.Z < MAP_BLOCKSIZE; pos.Z++) {
					n = block->getNodeNoEx(pos);
					c = n.getContent();

					// If content_t are not matching perform an LBM lookup
					if (previous_c != c) {
						lbm_list = (std::vector<LoadingBlockModifierDef *> *)
							it->second.lookup(c);
						previous_c = c;
					}

					if (!lbm_list)
						continue;
					for (auto lbmdef : *lbm_list) {
						lbmdef->trigger(env, pos + pos_of_block, n);
					}
				}
	}
}

/*
	ActiveBlockList
*/

void fillRadiusBlock(v3s16 p0, s16 r, std::set<v3s16> &list)
{
	v3s16 p;
	for(p.X=p0.X-r; p.X<=p0.X+r; p.X++)
		for(p.Y=p0.Y-r; p.Y<=p0.Y+r; p.Y++)
			for(p.Z=p0.Z-r; p.Z<=p0.Z+r; p.Z++)
			{
				// limit to a sphere
				if (p.getDistanceFrom(p0) <= r) {
					// Set in list
					list.insert(p);
				}
			}
}

void fillViewConeBlock(v3s16 p0,
	const s16 r,
	const v3f camera_pos,
	const v3f camera_dir,
	const float camera_fov,
	std::set<v3s16> &list)
{
	v3s16 p;
	const s16 r_nodes = r * BS * MAP_BLOCKSIZE;
	for (p.X = p0.X - r; p.X <= p0.X+r; p.X++)
	for (p.Y = p0.Y - r; p.Y <= p0.Y+r; p.Y++)
	for (p.Z = p0.Z - r; p.Z <= p0.Z+r; p.Z++) {
		if (isBlockInSight(p, camera_pos, camera_dir, camera_fov, r_nodes)) {
			list.insert(p);
		}
	}
}

void ActiveBlockList::update(std::vector<PlayerSAO*> &active_players,
	s16 active_block_range,
	s16 active_object_range,
	std::set<v3s16> &blocks_removed,
	std::set<v3s16> &blocks_added)
{
	/*
		Create the new list
	*/
	std::set<v3s16> newlist = m_forceloaded_list;
	m_abm_list = m_forceloaded_list;
	for (const PlayerSAO *playersao : active_players) {
		v3s16 pos = getNodeBlockPos(floatToInt(playersao->getBasePosition(), BS));
		fillRadiusBlock(pos, active_block_range, m_abm_list);
		fillRadiusBlock(pos, active_block_range, newlist);

		s16 player_ao_range = std::min(active_object_range, playersao->getWantedRange());
		// only do this if this would add blocks
		if (player_ao_range > active_block_range) {
			v3f camera_dir = v3f(0,0,1);
			camera_dir.rotateYZBy(playersao->getPitch());
			camera_dir.rotateXZBy(playersao->getYaw());
			fillViewConeBlock(pos,
				player_ao_range,
				playersao->getEyePosition(),
				camera_dir,
				playersao->getFov(),
				newlist);
		}
	}

	/*
		Find out which blocks on the old list are not on the new list
	*/
	// Go through old list
	for (v3s16 p : m_list) {
		// If not on new list, it's been removed
		if (newlist.find(p) == newlist.end())
			blocks_removed.insert(p);
	}

	/*
		Find out which blocks on the new list are not on the old list
	*/
	// Go through new list
	for (v3s16 p : newlist) {
		// If not on old list, it's been added
		if(m_list.find(p) == m_list.end())
			blocks_added.insert(p);
	}

	/*
		Update m_list
	*/
	m_list.clear();
	for (v3s16 p : newlist) {
		m_list.insert(p);
	}
}

/*
	ServerEnvironment
*/

ServerEnvironment::ServerEnvironment(ServerMap *map,
	ServerScripting *scriptIface, Server *server,
	const std::string &path_world):
	Environment(server),
	m_map(map),
	m_script(scriptIface),
	m_server(server),
	m_path_world(path_world)
{
	// Determine which database backend to use
	std::string conf_path = path_world + DIR_DELIM + "world.mt";
	Settings conf;
	bool succeeded = conf.readConfigFile(conf_path.c_str());
	if (!succeeded || !conf.exists("player_backend")) {
		// fall back to files
		conf.set("player_backend", "files");
		warningstream << "/!\\ You are using old player file backend. "
				<< "This backend is deprecated and will be removed in next release /!\\"
				<< std::endl << "Switching to SQLite3 or PostgreSQL is advised, "
				<< "please read http://wiki.minetest.net/Database_backends." << std::endl;

		if (!conf.updateConfigFile(conf_path.c_str())) {
			errorstream << "ServerEnvironment::ServerEnvironment(): "
				<< "Failed to update world.mt!" << std::endl;
		}
	}

	std::string name;
	conf.getNoEx("player_backend", name);
	m_player_database = openPlayerDatabase(name, path_world, conf);
}

ServerEnvironment::~ServerEnvironment()
{
	// Clear active block list.
	// This makes the next one delete all active objects.
	m_active_blocks.clear();

	// Convert all objects to static and delete the active objects
	deactivateFarObjects(true);

	// Drop/delete map
	m_map->drop();

	// Delete ActiveBlockModifiers
	for (ABMWithState &m_abm : m_abms) {
		delete m_abm.abm;
	}

	// Deallocate players
	for (RemotePlayer *m_player : m_players) {
		delete m_player;
	}

	delete m_player_database;
}

Map & ServerEnvironment::getMap()
{
	return *m_map;
}

ServerMap & ServerEnvironment::getServerMap()
{
	return *m_map;
}

RemotePlayer *ServerEnvironment::getPlayer(const session_t peer_id)
{
	for (RemotePlayer *player : m_players) {
		if (player->getPeerId() == peer_id)
			return player;
	}
	return NULL;
}

RemotePlayer *ServerEnvironment::getPlayer(const char* name)
{
	for (RemotePlayer *player : m_players) {
		if (strcmp(player->getName(), name) == 0)
			return player;
	}
	return NULL;
}

void ServerEnvironment::addPlayer(RemotePlayer *player)
{
	/*
		Check that peer_ids are unique.
		Also check that names are unique.
		Exception: there can be multiple players with peer_id=0
	*/
	// If peer id is non-zero, it has to be unique.
	if (player->getPeerId() != PEER_ID_INEXISTENT)
		FATAL_ERROR_IF(getPlayer(player->getPeerId()) != NULL, "Peer id not unique");
	// Name has to be unique.
	FATAL_ERROR_IF(getPlayer(player->getName()) != NULL, "Player name not unique");
	// Add.
	m_players.push_back(player);
}

void ServerEnvironment::removePlayer(RemotePlayer *player)
{
	for (std::vector<RemotePlayer *>::iterator it = m_players.begin();
		it != m_players.end(); ++it) {
		if ((*it) == player) {
			delete *it;
			m_players.erase(it);
			return;
		}
	}
}

bool ServerEnvironment::removePlayerFromDatabase(const std::string &name)
{
	return m_player_database->removePlayer(name);
}

bool ServerEnvironment::line_of_sight(v3f pos1, v3f pos2, v3s16 *p)
{
	// Iterate trough nodes on the line
	voxalgo::VoxelLineIterator iterator(pos1 / BS, (pos2 - pos1) / BS);
	do {
		MapNode n = getMap().getNodeNoEx(iterator.m_current_node_pos);

		// Return non-air
		if (n.param0 != CONTENT_AIR) {
			if (p)
				*p = iterator.m_current_node_pos;
			return false;
		}
		iterator.next();
	} while (iterator.m_current_index <= iterator.m_last_index);
	return true;
}

void ServerEnvironment::kickAllPlayers(AccessDeniedCode reason,
	const std::string &str_reason, bool reconnect)
{
	for (RemotePlayer *player : m_players) {
		m_server->DenyAccessVerCompliant(player->getPeerId(),
			player->protocol_version, reason, str_reason, reconnect);
	}
}

void ServerEnvironment::saveLoadedPlayers()
{
	std::string players_path = m_path_world + DIR_DELIM + "players";
	fs::CreateDir(players_path);

	for (RemotePlayer *player : m_players) {
		if (player->checkModified() || (player->getPlayerSAO() &&
				player->getPlayerSAO()->getMeta().isModified())) {
			try {
				m_player_database->savePlayer(player);
			} catch (DatabaseException &e) {
				errorstream << "Failed to save player " << player->getName() << " exception: "
					<< e.what() << std::endl;
				throw;
			}
		}
	}
}

void ServerEnvironment::savePlayer(RemotePlayer *player)
{
	try {
		m_player_database->savePlayer(player);
	} catch (DatabaseException &e) {
		errorstream << "Failed to save player " << player->getName() << " exception: "
			<< e.what() << std::endl;
		throw;
	}
}

PlayerSAO *ServerEnvironment::loadPlayer(RemotePlayer *player, bool *new_player,
	session_t peer_id, bool is_singleplayer)
{
	PlayerSAO *playersao = new PlayerSAO(this, player, peer_id, is_singleplayer);
	// Create player if it doesn't exist
	if (!m_player_database->loadPlayer(player, playersao)) {
		*new_player = true;
		// Set player position
		infostream << "Server: Finding spawn place for player \""
			<< player->getName() << "\"" << std::endl;
		playersao->setBasePosition(m_server->findSpawnPos());

		// Make sure the player is saved
		player->setModified(true);
	} else {
		// If the player exists, ensure that they respawn inside legal bounds
		// This fixes an assert crash when the player can't be added
		// to the environment
		if (objectpos_over_limit(playersao->getBasePosition())) {
			actionstream << "Respawn position for player \""
				<< player->getName() << "\" outside limits, resetting" << std::endl;
			playersao->setBasePosition(m_server->findSpawnPos());
		}
	}

	// Add player to environment
	addPlayer(player);

	/* Clean up old HUD elements from previous sessions */
	player->clearHud();

	/* Add object to environment */
	addActiveObject(playersao);

	return playersao;
}

void ServerEnvironment::saveMeta()
{
	std::string path = m_path_world + DIR_DELIM "env_meta.txt";

	// Open file and serialize
	std::ostringstream ss(std::ios_base::binary);

	Settings args;
	args.setU64("game_time", m_game_time);
	args.setU64("time_of_day", getTimeOfDay());
	args.setU64("last_clear_objects_time", m_last_clear_objects_time);
	args.setU64("lbm_introduction_times_version", 1);
	args.set("lbm_introduction_times",
		m_lbm_mgr.createIntroductionTimesString());
	args.setU64("day_count", m_day_count);
	args.writeLines(ss);
	ss<<"EnvArgsEnd\n";

	if(!fs::safeWriteToFile(path, ss.str()))
	{
		infostream<<"ServerEnvironment::saveMeta(): Failed to write "
			<<path<<std::endl;
		throw SerializationError("Couldn't save env meta");
	}
}

void ServerEnvironment::loadMeta()
{
	// If file doesn't exist, load default environment metadata
	if (!fs::PathExists(m_path_world + DIR_DELIM "env_meta.txt")) {
		infostream << "ServerEnvironment: Loading default environment metadata"
			<< std::endl;
		loadDefaultMeta();
		return;
	}

	infostream << "ServerEnvironment: Loading environment metadata" << std::endl;

	std::string path = m_path_world + DIR_DELIM "env_meta.txt";

	// Open file and deserialize
	std::ifstream is(path.c_str(), std::ios_base::binary);
	if (!is.good()) {
		infostream << "ServerEnvironment::loadMeta(): Failed to open "
			<< path << std::endl;
		throw SerializationError("Couldn't load env meta");
	}

	Settings args;

	if (!args.parseConfigLines(is, "EnvArgsEnd")) {
		throw SerializationError("ServerEnvironment::loadMeta(): "
			"EnvArgsEnd not found!");
	}

	try {
		m_game_time = args.getU64("game_time");
	} catch (SettingNotFoundException &e) {
		// Getting this is crucial, otherwise timestamps are useless
		throw SerializationError("Couldn't load env meta game_time");
	}

	setTimeOfDay(args.exists("time_of_day") ?
		// set day to early morning by default
		args.getU64("time_of_day") : 5250);

	m_last_clear_objects_time = args.exists("last_clear_objects_time") ?
		// If missing, do as if clearObjects was never called
		args.getU64("last_clear_objects_time") : 0;

	std::string lbm_introduction_times;
	try {
		u64 ver = args.getU64("lbm_introduction_times_version");
		if (ver == 1) {
			lbm_introduction_times = args.get("lbm_introduction_times");
		} else {
			infostream << "ServerEnvironment::loadMeta(): Non-supported"
				<< " introduction time version " << ver << std::endl;
		}
	} catch (SettingNotFoundException &e) {
		// No problem, this is expected. Just continue with an empty string
	}
	m_lbm_mgr.loadIntroductionTimes(lbm_introduction_times, m_server, m_game_time);

	m_day_count = args.exists("day_count") ?
		args.getU64("day_count") : 0;
}

/**
 * called if env_meta.txt doesn't exist (e.g. new world)
 */
void ServerEnvironment::loadDefaultMeta()
{
	m_lbm_mgr.loadIntroductionTimes("", m_server, m_game_time);
}

struct ActiveABM
{
	ActiveBlockModifier *abm;
	int chance;
	std::vector<content_t> required_neighbors;
	bool check_required_neighbors; // false if required_neighbors is known to be empty
};

class ABMHandler
{
private:
	ServerEnvironment *m_env;
	std::vector<std::vector<ActiveABM> *> m_aabms;
public:
	ABMHandler(std::vector<ABMWithState> &abms,
		float dtime_s, ServerEnvironment *env,
		bool use_timers):
		m_env(env)
	{
		if(dtime_s < 0.001)
			return;
		const NodeDefManager *ndef = env->getGameDef()->ndef();
		for (ABMWithState &abmws : abms) {
			ActiveBlockModifier *abm = abmws.abm;
			float trigger_interval = abm->getTriggerInterval();
			if(trigger_interval < 0.001)
				trigger_interval = 0.001;
			float actual_interval = dtime_s;
			if(use_timers){
				abmws.timer += dtime_s;
				if(abmws.timer < trigger_interval)
					continue;
				abmws.timer -= trigger_interval;
				actual_interval = trigger_interval;
			}
			float chance = abm->getTriggerChance();
			if(chance == 0)
				chance = 1;
			ActiveABM aabm;
			aabm.abm = abm;
			if (abm->getSimpleCatchUp()) {
				float intervals = actual_interval / trigger_interval;
				if(intervals == 0)
					continue;
				aabm.chance = chance / intervals;
				if(aabm.chance == 0)
					aabm.chance = 1;
			} else {
				aabm.chance = chance;
			}

			// Trigger neighbors
			const std::vector<std::string> &required_neighbors_s =
				abm->getRequiredNeighbors();
			for (const std::string &required_neighbor_s : required_neighbors_s) {
				ndef->getIds(required_neighbor_s, aabm.required_neighbors);
			}
			aabm.check_required_neighbors = !required_neighbors_s.empty();

			// Trigger contents
			const std::vector<std::string> &contents_s = abm->getTriggerContents();
			for (const std::string &content_s : contents_s) {
				std::vector<content_t> ids;
				ndef->getIds(content_s, ids);
				for (content_t c : ids) {
					if (c >= m_aabms.size())
						m_aabms.resize(c + 256, NULL);
					if (!m_aabms[c])
						m_aabms[c] = new std::vector<ActiveABM>;
					m_aabms[c]->push_back(aabm);
				}
			}
		}
	}

	~ABMHandler()
	{
		for (auto &aabms : m_aabms)
			delete aabms;
	}

	// Find out how many objects the given block and its neighbours contain.
	// Returns the number of objects in the block, and also in 'wider' the
	// number of objects in the block and all its neighbours. The latter
	// may an estimate if any neighbours are unloaded.
	u32 countObjects(MapBlock *block, ServerMap * map, u32 &wider)
	{
		wider = 0;
		u32 wider_unknown_count = 0;
		for(s16 x=-1; x<=1; x++)
			for(s16 y=-1; y<=1; y++)
				for(s16 z=-1; z<=1; z++)
				{
					MapBlock *block2 = map->getBlockNoCreateNoEx(
						block->getPos() + v3s16(x,y,z));
					if(block2==NULL){
						wider_unknown_count++;
						continue;
					}
					wider += block2->m_static_objects.m_active.size()
						+ block2->m_static_objects.m_stored.size();
				}
		// Extrapolate
		u32 active_object_count = block->m_static_objects.m_active.size();
		u32 wider_known_count = 3*3*3 - wider_unknown_count;
		wider += wider_unknown_count * wider / wider_known_count;
		return active_object_count;

	}
	void apply(MapBlock *block, int &blocks_scanned, int &abms_run, int &blocks_cached)
	{
		if(m_aabms.empty() || block->isDummy())
			return;

		// Check the content type cache first
		// to see whether there are any ABMs
		// to be run at all for this block.
		if (block->contents_cached) {
			blocks_cached++;
			bool run_abms = false;
			for (content_t c : block->contents) {
				if (c < m_aabms.size() && m_aabms[c]) {
					run_abms = true;
					break;
				}
			}
			if (!run_abms)
				return;
		} else {
			// Clear any caching
			block->contents.clear();
		}
		blocks_scanned++;

		ServerMap *map = &m_env->getServerMap();

		u32 active_object_count_wider;
		u32 active_object_count = this->countObjects(block, map, active_object_count_wider);
		m_env->m_added_objects = 0;

		v3s16 p0;
		for(p0.X=0; p0.X<MAP_BLOCKSIZE; p0.X++)
		for(p0.Y=0; p0.Y<MAP_BLOCKSIZE; p0.Y++)
		for(p0.Z=0; p0.Z<MAP_BLOCKSIZE; p0.Z++)
		{
			const MapNode &n = block->getNodeUnsafe(p0);
			content_t c = n.getContent();
			// Cache content types as we go
			if (!block->contents_cached && !block->do_not_cache_contents) {
				block->contents.insert(c);
				if (block->contents.size() > 64) {
					// Too many different nodes... don't try to cache
					block->do_not_cache_contents = true;
					block->contents.clear();
				}
			}

			if (c >= m_aabms.size() || !m_aabms[c])
				continue;

			v3s16 p = p0 + block->getPosRelative();
			for (ActiveABM &aabm : *m_aabms[c]) {
				if (myrand() % aabm.chance != 0)
					continue;

				// Check neighbors
				if (aabm.check_required_neighbors) {
					v3s16 p1;
					for(p1.X = p0.X-1; p1.X <= p0.X+1; p1.X++)
					for(p1.Y = p0.Y-1; p1.Y <= p0.Y+1; p1.Y++)
					for(p1.Z = p0.Z-1; p1.Z <= p0.Z+1; p1.Z++)
					{
						if(p1 == p0)
							continue;
						content_t c;
						if (block->isValidPosition(p1)) {
							// if the neighbor is found on the same map block
							// get it straight from there
							const MapNode &n = block->getNodeUnsafe(p1);
							c = n.getContent();
						} else {
							// otherwise consult the map
							MapNode n = map->getNodeNoEx(p1 + block->getPosRelative());
							c = n.getContent();
						}
						if (CONTAINS(aabm.required_neighbors, c))
							goto neighbor_found;
					}
					// No required neighbor found
					continue;
				}
				neighbor_found:

				abms_run++;
				// Call all the trigger variations
				aabm.abm->trigger(m_env, p, n);
				aabm.abm->trigger(m_env, p, n,
					active_object_count, active_object_count_wider);

				// Count surrounding objects again if the abms added any
				if(m_env->m_added_objects > 0) {
					active_object_count = countObjects(block, map, active_object_count_wider);
					m_env->m_added_objects = 0;
				}
			}
		}
		block->contents_cached = !block->do_not_cache_contents;
	}
};

void ServerEnvironment::activateBlock(MapBlock *block, u32 additional_dtime)
{
	// Reset usage timer immediately, otherwise a block that becomes active
	// again at around the same time as it would normally be unloaded will
	// get unloaded incorrectly. (I think this still leaves a small possibility
	// of a race condition between this and server::AsyncRunStep, which only
	// some kind of synchronisation will fix, but it at least reduces the window
	// of opportunity for it to break from seconds to nanoseconds)
	block->resetUsageTimer();

	// Get time difference
	u32 dtime_s = 0;
	u32 stamp = block->getTimestamp();
	if (m_game_time > stamp && stamp != BLOCK_TIMESTAMP_UNDEFINED)
		dtime_s = m_game_time - stamp;
	dtime_s += additional_dtime;

	/*infostream<<"ServerEnvironment::activateBlock(): block timestamp: "
			<<stamp<<", game time: "<<m_game_time<<std::endl;*/

	// Remove stored static objects if clearObjects was called since block's timestamp
	if (stamp == BLOCK_TIMESTAMP_UNDEFINED || stamp < m_last_clear_objects_time) {
		block->m_static_objects.m_stored.clear();
		// do not set changed flag to avoid unnecessary mapblock writes
	}

	// Set current time as timestamp
	block->setTimestampNoChangedFlag(m_game_time);

	/*infostream<<"ServerEnvironment::activateBlock(): block is "
			<<dtime_s<<" seconds old."<<std::endl;*/

	// Activate stored objects
	activateObjects(block, dtime_s);

	/* Handle LoadingBlockModifiers */
	m_lbm_mgr.applyLBMs(this, block, stamp);

	// Run node timers
	std::vector<NodeTimer> elapsed_timers =
		block->m_node_timers.step((float)dtime_s);
	if (!elapsed_timers.empty()) {
		MapNode n;
		for (const NodeTimer &elapsed_timer : elapsed_timers) {
			n = block->getNodeNoEx(elapsed_timer.position);
			v3s16 p = elapsed_timer.position + block->getPosRelative();
			if (m_script->node_on_timer(p, n, elapsed_timer.elapsed))
				block->setNodeTimer(NodeTimer(elapsed_timer.timeout, 0,
					elapsed_timer.position));
		}
	}
}

void ServerEnvironment::addActiveBlockModifier(ActiveBlockModifier *abm)
{
	m_abms.emplace_back(abm);
}
Mode	Name	Size
-rw-r--r--	apple.png	203	log plain
-rw-r--r--	apple_iron.png	207	log plain
-rw-r--r--	book.png	292	log plain
-rw-r--r--	bookshelf.png	597	log plain
-rw-r--r--	brick.png	604	log plain
-rw-r--r--	cactus_side.png	279	log plain
-rw-r--r--	cactus_top.png	236	log plain
-rw-r--r--	chest_front.png	167	log plain
-rw-r--r--	chest_side.png	151	log plain
-rw-r--r--	chest_top.png	142	log plain
-rw-r--r--	clay.png	613	log plain
-rw-r--r--	clay_brick.png	249	log plain
-rw-r--r--	cloud.png	118	log plain
-rw-r--r--	cobble.png	830	log plain
-rw-r--r--	cooked_rat.png	239	log plain
-rw-r--r--	crack.png	1076	log plain
-rw-r--r--	fence.png	539	log plain
-rw-r--r--	firefly.png	116	log plain
-rw-r--r--	fontlucida.png	17284	log plain
-rw-r--r--	furnace_front.png	246	log plain
-rw-r--r--	furnace_side.png	236	log plain
-rw-r--r--	glass.png	1309	log plain
-rw-r--r--	grass.png	874	log plain
-rw-r--r--	grass_footsteps.png	856	log plain
-rw-r--r--	grass_side.png	878	log plain
-rw-r--r--	gravel.png	591	log plain
-rw-r--r--	heart.png	308	log plain
-rw-r--r--	junglegrass.png	672	log plain
-rw-r--r--	jungletree.png	502	log plain
-rw-r--r--	jungletree_top.png	507	log plain
-rw-r--r--	ladder.png	395	log plain
-rw-r--r--	lava.png	357	log plain
-rw-r--r--	leaves.png	1689	log plain
-rw-r--r--	lump_of_clay.png	210	log plain
-rw-r--r--	lump_of_coal.png	933	log plain
-rw-r--r--	lump_of_iron.png	936	log plain
-rw-r--r--	menulogo.png	498	log plain
-rw-r--r--	mese.png	203	log plain
-rw-r--r--	mineral_coal.png	952	log plain
-rw-r--r--	mineral_iron.png	1614	log plain
-rw-r--r--	mossycobble.png	965	log plain
-rw-r--r--	mud.png	1586	log plain
-rw-r--r--	nc_back.png	303	log plain
-rw-r--r--	nc_front.png	410	log plain
-rw-r--r--	nc_rb.png	203	log plain
-rw-r--r--	nc_side.png	260	log plain
-rw-r--r--	oerkki1.png	250	log plain
-rw-r--r--	oerkki1_damaged.png	341	log plain
-rw-r--r--	paper.png	242	log plain
-rw-r--r--	papyrus.png	366	log plain
-rw-r--r--	player.png	212	log plain
-rw-r--r--	player_back.png	201	log plain
-rw-r--r--	rail.png	507	log plain
-rw-r--r--	rail_crossing.png	555	log plain
-rw-r--r--	rail_curved.png	545	log plain
-rw-r--r--	rail_t_junction.png	542	log plain
-rw-r--r--	rat.png	920	log plain
-rw-r--r--	sand.png	1381	log plain
-rw-r--r--	sandstone.png	772	log plain
-rw-r--r--	scorched_stuff.png	233	log plain
-rw-r--r--	sign.png	1374	log plain
-rw-r--r--	sign_back.png	1312	log plain
-rw-r--r--	sign_wall.png	489	log plain
-rw-r--r--	skybox1.png	236	log plain
-rw-r--r--	skybox1_dawn.png	598	log plain
-rw-r--r--	skybox1_night.png	2247	log plain
-rw-r--r--	skybox2.png	231	log plain
-rw-r--r--	skybox2_dawn.png	199	log plain
-rw-r--r--	skybox2_night.png	2583	log plain
-rw-r--r--	skybox3.png	190	log plain
-rw-r--r--	skybox3_dawn.png	190	log plain
-rw-r--r--	skybox3_night.png	190	log plain
-rw-r--r--	steel_block.png	219	log plain
-rw-r--r--	steel_ingot.png	207	log plain
-rw-r--r--	stick.png	182	log plain
-rw-r--r--	stone.png	806	log plain
-rw-r--r--	tool_mesepick.png	252	log plain
-rw-r--r--	tool_steelaxe.png	209	log plain
-rw-r--r--	tool_steelpick.png	271	log plain
-rw-r--r--	tool_steelshovel.png	216	log plain
-rw-r--r--	tool_steelsword.png	291	log plain
-rw-r--r--	tool_stoneaxe.png	193	log plain
-rw-r--r--	tool_stonepick.png	262	log plain
-rw-r--r--	tool_stoneshovel.png	203	log plain
-rw-r--r--	tool_stonesword.png	301	log plain
-rw-r--r--	tool_woodaxe.png	190	log plain
-rw-r--r--	tool_woodpick.png	245	log plain
-rw-r--r--	tool_woodshovel.png	203	log plain
-rw-r--r--	tool_woodsword.png	255	log plain
-rw-r--r--	torch.png	925	log plain
-rw-r--r--	torch_on_ceiling.png	913	log plain
-rw-r--r--	torch_on_floor.png	917	log plain
-rw-r--r--	tree.png	1445	log plain
-rw-r--r--	tree_top.png	1024	log plain
-rw-r--r--	treeprop.png	1055	log plain
-rw-r--r--	unknown_block.png	582	log plain
-rw-r--r--	water.png	518	log plain
-rw-r--r--	wood.png	1400	log plain