/*
Minetest
Copyright (C) 2010-2013 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 "localplayer.h"

#include "event.h"
#include "collision.h"
#include "nodedef.h"
#include "settings.h"
#include "environment.h"
#include "map.h"
#include "client.h"
#include "content_cao.h"

/*
	LocalPlayer
*/

LocalPlayer::LocalPlayer(Client *client, const char *name):
	Player(name, client->idef()),
	m_client(client)
{
}

static aabb3f getNodeBoundingBox(const std::vector<aabb3f> &nodeboxes)
{
	if (nodeboxes.empty())
		return aabb3f(0, 0, 0, 0, 0, 0);

	aabb3f b_max;

	std::vector<aabb3f>::const_iterator it = nodeboxes.begin();
	b_max = aabb3f(it->MinEdge, it->MaxEdge);

	++it;
	for (; it != nodeboxes.end(); ++it)
		b_max.addInternalBox(*it);

	return b_max;
}

bool LocalPlayer::updateSneakNode(Map *map, const v3f &position,
		const v3f &sneak_max)
{
	static const v3s16 dir9_center[9] = {
		v3s16( 0, 0,  0),
		v3s16( 1, 0,  0),
		v3s16(-1, 0,  0),
		v3s16( 0, 0,  1),
		v3s16( 0, 0, -1),
		v3s16( 1, 0,  1),
		v3s16(-1, 0,  1),
		v3s16( 1, 0, -1),
		v3s16(-1, 0, -1)
	};

	const NodeDefManager *nodemgr = m_client->ndef();
	MapNode node;
	bool is_valid_position;
	bool new_sneak_node_exists = m_sneak_node_exists;

	// We want the top of the sneak node to be below the players feet
	f32 position_y_mod = 0.05 * BS;
	if (m_sneak_node_exists)
		position_y_mod = m_sneak_node_bb_top.MaxEdge.Y - position_y_mod;

	// Get position of current standing node
	const v3s16 current_node = floatToInt(position - v3f(0, position_y_mod, 0), BS);

	if (current_node != m_sneak_node) {
		new_sneak_node_exists = false;
	} else {
		node = map->getNodeNoEx(current_node, &is_valid_position);
		if (!is_valid_position || !nodemgr->get(node).walkable)
			new_sneak_node_exists = false;
	}

	// Keep old sneak node
	if (new_sneak_node_exists)
		return true;

	// Get new sneak node
	m_sneak_ladder_detected = false;
	f32 min_distance_f = 100000.0 * BS;

	for (const auto &d : dir9_center) {
		const v3s16 p = current_node + d;
		const v3f pf = intToFloat(p, BS);
		const v2f diff(position.X - pf.X, position.Z - pf.Z);
		f32 distance_f = diff.getLength();

		if (distance_f > min_distance_f ||
				fabs(diff.X) > (.5 + .1) * BS + sneak_max.X ||
				fabs(diff.Y) > (.5 + .1) * BS + sneak_max.Z)
			continue;


		// The node to be sneaked on has to be walkable
		node = map->getNodeNoEx(p, &is_valid_position);
		if (!is_valid_position || !nodemgr->get(node).walkable)
			continue;
		// And the node(s) above have to be nonwalkable
		bool ok = true;
		if (!physics_override_sneak_glitch) {
			u16 height = ceilf(
					(m_collisionbox.MaxEdge.Y - m_collisionbox.MinEdge.Y) / BS
			);
			for (u16 y = 1; y <= height; y++) {
				node = map->getNodeNoEx(p + v3s16(0, y, 0), &is_valid_position);
				if (!is_valid_position || nodemgr->get(node).walkable) {
					ok = false;
					break;
				}
			}
		} else {
			// legacy behaviour: check just one node
			node = map->getNodeNoEx(p + v3s16(0, 1, 0), &is_valid_position);
			ok = is_valid_position && !nodemgr->get(node).walkable;
		}
		if (!ok)
			continue;

		min_distance_f = distance_f;
		m_sneak_node = p;
		new_sneak_node_exists = true;
	}

	if (!new_sneak_node_exists)
		return false;

	// Update saved top bounding box of sneak node
	node = map->getNodeNoEx(m_sneak_node);
	std::vector<aabb3f> nodeboxes;
	node.getCollisionBoxes(nodemgr, &nodeboxes);
	m_sneak_node_bb_top = getNodeBoundingBox(nodeboxes);

	if (physics_override_sneak_glitch) {
		// Detect sneak ladder:
		// Node two meters above sneak node must be solid
		node = map->getNodeNoEx(m_sneak_node + v3s16(0, 2, 0),
			&is_valid_position);
		if (is_valid_position && nodemgr->get(node).walkable) {
			// Node three meters above: must be non-solid
			node = map->getNodeNoEx(m_sneak_node + v3s16(0, 3, 0),
				&is_valid_position);
			m_sneak_ladder_detected = is_valid_position &&
				!nodemgr->get(node).walkable;
		}
	}
	return true;
}

void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d,
		std::vector<CollisionInfo> *collision_info)
{
	if (!collision_info || collision_info->empty()) {
		// Node below the feet, update each ClientEnvironment::step()
		m_standing_node = floatToInt(m_position, BS) - v3s16(0, 1, 0);
	}

	// Temporary option for old move code
	if (!physics_override_new_move) {
		old_move(dtime, env, pos_max_d, collision_info);
		return;
	}

	Map *map = &env->getMap();
	const NodeDefManager *nodemgr = m_client->ndef();

	v3f position = getPosition();

	// Copy parent position if local player is attached
	if (isAttached) {
		setPosition(overridePosition);
		return;
	}

	// Skip collision detection if noclip mode is used
	bool fly_allowed = m_client->checkLocalPrivilege("fly");
	bool noclip = m_client->checkLocalPrivilege("noclip") &&
		g_settings->getBool("noclip");
	bool free_move = g_settings->getBool("free_move") && fly_allowed;

	if (noclip && free_move) {
		position += m_speed * dtime;
		setPosition(position);
		return;
	}

	/*
		Collision detection
	*/

	bool is_valid_position;
	MapNode node;
	v3s16 pp;

	/*
		Check if player is in liquid (the oscillating value)
	*/

	// If in liquid, the threshold of coming out is at higher y
	if (in_liquid)
	{
		pp = floatToInt(position + v3f(0,BS*0.1,0), BS);
		node = map->getNodeNoEx(pp, &is_valid_position);
		if (is_valid_position) {
			in_liquid = nodemgr->get(node.getContent()).isLiquid();
			liquid_viscosity = nodemgr->get(node.getContent()).liquid_viscosity;
		} else {
			in_liquid = false;
		}
	}
	// If not in liquid, the threshold of going in is at lower y
	else
	{
		pp = floatToInt(position + v3f(0,BS*0.5,0), BS);
		node = map->getNodeNoEx(pp, &is_valid_position);
		if (is_valid_position) {
			in_liquid = nodemgr->get(node.getContent()).isLiquid();
			liquid_viscosity = nodemgr->get(node.getContent()).liquid_viscosity;
		} else {
			in_liquid = false;
		}
	}


	/*
		Check if player is in liquid (the stable value)
	*/
	pp = floatToInt(position + v3f(0,0,0), BS);
	node = map->getNodeNoEx(pp, &is_valid_position);
	if (is_valid_position) {
		in_liquid_stable = nodemgr->get(node.getContent()).isLiquid();
	} else {
		in_liquid_stable = false;
	}

	/*
	        Check if player is climbing
	*/


	pp = floatToInt(position + v3f(0,0.5*BS,0), BS);
	v3s16 pp2 = floatToInt(position + v3f(0,-0.2*BS,0), BS);
	node = map->getNodeNoEx(pp, &is_valid_position);
	bool is_valid_position2;
	MapNode node2 = map->getNodeNoEx(pp2, &is_valid_position2);

	if (!(is_valid_position && is_valid_position2)) {
		is_climbing = false;
	} else {
		is_climbing = (nodemgr->get(node.getContent()).climbable
				|| nodemgr->get(node2.getContent()).climbable) && !free_move;
	}

	/*
		Collision uncertainty radius
		Make it a bit larger than the maximum distance of movement
	*/
	//f32 d = pos_max_d * 1.1;
	// A fairly large value in here makes moving smoother
	f32 d = 0.15*BS;

	// This should always apply, otherwise there are glitches
	sanity_check(d > pos_max_d);

	// Player object property step height is multiplied by BS in
	// /src/script/common/c_content.cpp and /src/content_sao.cpp
	float player_stepheight = (m_cao == nullptr) ? 0.0f :
		(touching_ground ? m_cao->getStepHeight() : (0.2f * BS));

	// TODO this is a problematic hack.
	// Use a better implementation for autojump, or apply a custom stepheight
	// to all players, as this currently creates unintended special movement
	// abilities and advantages for Android players on a server.
#ifdef __ANDROID__
	if (touching_ground)
		player_stepheight += (0.6f * BS);
#endif

	v3f accel_f = v3f(0,0,0);

	collisionMoveResult result = collisionMoveSimple(env, m_client,
		pos_max_d, m_collisionbox, player_stepheight, dtime,
		&position, &m_speed, accel_f);

	bool could_sneak = control.sneak && !free_move && !in_liquid &&
		!is_climbing && physics_override_sneak;

	// Add new collisions to the vector
	if (collision_info && !free_move) {
		v3f diff = intToFloat(m_standing_node, BS) - position;
		f32 distance = diff.getLength();
		// Force update each ClientEnvironment::step()
		bool is_first = collision_info->empty();

		for (const auto &colinfo : result.collisions) {
			collision_info->push_back(colinfo);

			if (colinfo.type != COLLISION_NODE ||
					colinfo.new_speed.Y != 0 ||
					(could_sneak && m_sneak_node_exists))
				continue;

			diff = intToFloat(colinfo.node_p, BS) - position;

			// Find nearest colliding node
			f32 len = diff.getLength();
			if (is_first || len < distance) {
				m_standing_node = colinfo.node_p;
				distance = len;
			}
		}
	}

	/*
		If the player's feet touch the topside of any node, this is
		set to true.

		Player is allowed to jump when this is true.
	*/
	bool touching_ground_was = touching_ground;
	touching_ground = result.touching_ground;
	bool sneak_can_jump = false;

	// Max. distance (X, Z) over border for sneaking determined by collision box
	// * 0.49 to keep the center just barely on the node
	v3f sneak_max = m_collisionbox.getExtent() * 0.49;

	if (m_sneak_ladder_detected) {
		// restore legacy behaviour (this makes the m_speed.Y hack necessary)
		sneak_max = v3f(0.4 * BS, 0, 0.4 * BS);
	}

	/*
		If sneaking, keep on top of last walked node and don't fall off
	*/
	if (could_sneak && m_sneak_node_exists) {
		const v3f sn_f = intToFloat(m_sneak_node, BS);
		const v3f bmin = sn_f + m_sneak_node_bb_top.MinEdge;
		const v3f bmax = sn_f + m_sneak_node_bb_top.MaxEdge;
		const v3f old_pos = position;
		const v3f old_speed = m_speed;
		f32 y_diff = bmax.Y - position.Y;
		m_standing_node = m_sneak_node;

		// (BS * 0.6f) is the basic stepheight while standing on ground
		if (y_diff < BS * 0.6f) {
			// Only center player when they're on the node
			position.X = rangelim(position.X,
				bmin.X - sneak_max.X, bmax.X + sneak_max.X);
			position.Z = rangelim(position.Z,
				bmin.Z - sneak_max.Z, bmax.Z + sneak_max.Z);

			if (position.X != old_pos.X)
				m_speed.X = 0;
			if (position.Z != old_pos.Z)
				m_speed.Z = 0;
		}

		if (y_diff > 0 && m_speed.Y < 0 &&
				(physics_override_sneak_glitch || y_diff < BS * 0.6f)) {
			// Move player to the maximal height when falling or when
			// the ledge is climbed on the next step.
			position.Y = bmax.Y;
			m_speed.Y = 0;
		}

		// Allow jumping on node edges while sneaking
		if (m_speed.Y == 0 || m_sneak_ladder_detected)
			sneak_can_jump = true;

		if (collision_info &&
				m_speed.Y - old_speed.Y > BS) {
			// Collide with sneak node, report fall damage
			CollisionInfo sn_info;
			sn_info.node_p = m_sneak_node;
			sn_info.old_speed = old_speed;
			sn_info.new_speed = m_speed;
			collision_info->push_back(sn_info);
		}
	}

	/*
		Find the next sneak node if necessary
	*/
	bool new_sneak_node_exists = false;

	if (could_sneak)
		new_sneak_node_exists = updateSneakNode(map, position, sneak_max);

	/*
		Set new position but keep sneak node set
	*/
	setPosition(position);
	m_sneak_node_exists = new_sneak_node_exists;

	/*
		Report collisions
	*/

	if(!result.standing_on_object && !touching_ground_was && touching_ground) {
		MtEvent *e = new SimpleTriggerEvent("PlayerRegainGround");
		m_client->event()->put(e);

		// Set camera impact value to be used for view bobbing
		camera_impact = getSpeed().Y * -1;
	}

	{
		camera_barely_in_ceiling = false;
		v3s16 camera_np = floatToInt(getEyePosition(), BS);
		MapNode n = map->getNodeNoEx(camera_np);
		if(n.getContent() != CONTENT_IGNORE){
			if(nodemgr->get(n).walkable && nodemgr->get(n).solidness == 2){
				camera_barely_in_ceiling = true;
			}
		}
	}

	/*
		Check properties of the node on which the player is standing
	*/
	const ContentFeatures &f = nodemgr->get(map->getNodeNoEx(m_standing_node));
	// Determine if jumping is possible
	m_can_jump = (touching_ground && !in_liquid && !is_climbing)
			|| sneak_can_jump;
	if (itemgroup_get(f.groups, "disable_jump"))
		m_can_jump = false;

	// Jump key pressed while jumping off from a bouncy block
	if (m_can_jump && control.jump && itemgroup_get(f.groups, "bouncy") &&
		m_speed.Y >= -0.5 * BS) {
		float jumpspeed = movement_speed_jump * physics_override_jump;
		if (m_speed.Y > 1) {
			// Reduce boost when speed already is high
			m_speed.Y += jumpspeed / (1 + (m_speed.Y / 16 ));
		} else {
			m_speed.Y += jumpspeed;
		}
		setSpeed(m_speed);
		m_can_jump = false;
	}
}

void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d)
{
	move(dtime, env, pos_max_d, NULL);
}

void LocalPlayer::applyControl(float dtime, Environment *env)
{
	// Clear stuff
	swimming_vertical = false;

	setPitch(control.pitch);
	setYaw(control.yaw);

	// Nullify speed and don't run positioning code if the player is attached
	if(isAttached)
	{
		setSpeed(v3f(0,0,0));
		return;
	}

	v3f move_direction = v3f(0,0,1);
	move_direction.rotateXZBy(getYaw());

	v3f speedH = v3f(0,0,0); // Horizontal (X, Z)
	v3f speedV = v3f(0,0,0); // Vertical (Y)

	bool fly_allowed = m_client->checkLocalPrivilege("fly");
	bool fast_allowed = m_client->checkLocalPrivilege("fast");

	bool free_move = fly_allowed && g_settings->getBool("free_move");
	bool fast_move = fast_allowed && g_settings->getBool("fast_move");
	// When aux1_descends is enabled the fast key is used to go down, so fast isn't possible
	bool fast_climb = fast_move && control.aux1 && !g_settings->getBool("aux1_descends");
	bool continuous_forward = g_settings->getBool("continuous_forward");
	bool always_fly_fast = g_settings->getBool("always_fly_fast");

	// Whether superspeed mode is used or not
	bool superspeed = false;

	if (always_fly_fast && free_move && fast_move)
		superspeed = true;

	// Old descend control
	if(g_settings->getBool("aux1_descends"))
	{
		// If free movement and fast movement, always move fast
		if(free_move && fast_move)
			superspeed = true;

		// Auxiliary button 1 (E)
		if(control.aux1)
		{
			if(free_move)
			{
				// In free movement mode, aux1 descends
				if(fast_move)
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_walk;
			}
			else if(in_liquid || in_liquid_stable)
			{
				speedV.Y = -movement_speed_walk;
				swimming_vertical = true;
			}
			else if(is_climbing)
			{
				speedV.Y = -movement_speed_climb;
			}
			else
			{
				// If not free movement but fast is allowed, aux1 is
				// "Turbo button"
				if(fast_move)
					superspeed = true;
			}
		}
	}
	// New minecraft-like descend control
	else
	{
		// Auxiliary button 1 (E)
		if(control.aux1)
		{
			if(!is_climbing)
			{
				// aux1 is "Turbo button"
				if(fast_move)
					superspeed = true;
			}
		}

		if(control.sneak)
		{
			if(free_move)
			{
				// In free movement mode, sneak descends
				if (fast_move && (control.aux1 || always_fly_fast))
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_walk;
			}
			else if(in_liquid || in_liquid_stable)
			{
				if(fast_climb)
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_walk;
				swimming_vertical = true;
			}
			else if(is_climbing)
			{
				if(fast_climb)
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_climb;
			}
		}
	}

	if (continuous_forward)
		speedH += move_direction;

	if (control.up) {
		if (continuous_forward) {
			if (fast_move)
				superspeed = true;
		} else {
			speedH += move_direction;
		}
	}
	if (control.down) {
		speedH -= move_direction;
	}
	if (!control.up && !control.down) {
		speedH -= move_direction *
			(control.forw_move_joystick_axis / 32767.f);
	}
	if (control.left) {
		speedH += move_direction.crossProduct(v3f(0,1,0));
	}
	if (control.right) {
		speedH += move_direction.crossProduct(v3f(0,-1,0));
	}
	if (!control.left && !control.right) {
		speedH -= move_direction.crossProduct(v3f(0,1,0)) *
			(control.sidew_move_joystick_axis / 32767.f);
	}
	if(control.jump)
	{
		if (free_move) {
			if (g_settings->getBool("aux1_descends") || always_fly_fast) {
				if (fast_move)
					speedV.Y = movement_speed_fast;
				else
					speedV.Y = movement_speed_walk;
			} else {
				if(fast_move && control.aux1)
					speedV.Y = movement_speed_fast;
				else
					speedV.Y = movement_speed_walk;
			}
		}
		else if(m_can_jump)
		{
			/*
				NOTE: The d value in move() affects jump height by
				raising the height at which the jump speed is kept
				at its starting value
			*/
			v3f speedJ = getSpeed();
			if(speedJ.Y >= -0.5 * BS) {
				speedJ.Y = movement_speed_jump * physics_override_jump;
				setSpeed(speedJ);

				MtEvent *e = new SimpleTriggerEvent("PlayerJump");
				m_client->event()->put(e);
			}
		}
		else if(in_liquid)
		{
			if(fast_climb)
				speedV.Y = movement_speed_fast;
			else
				speedV.Y = movement_speed_walk;
			swimming_vertical = true;
		}
		else if(is_climbing)
		{
			if(fast_climb)
				speedV.Y = movement_speed_fast;
			else
				speedV.Y = movement_speed_climb;
		}
	}

	// The speed of the player (Y is ignored)
	if(superspeed || (is_climbing && fast_climb) || ((in_liquid || in_liquid_stable) && fast_climb))
		speedH = speedH.normalize() * movement_speed_fast;
	else if(control.sneak && !free_move && !in_liquid && !in_liquid_stable)
		speedH = speedH.normalize() * movement_speed_crouch;
	else
		speedH = speedH.normalize() * movement_speed_walk;

	// Acceleration increase
	f32 incH = 0; // Horizontal (X, Z)
	f32 incV = 0; // Vertical (Y)
	if((!touching_ground && !free_move && !is_climbing && !in_liquid) || (!free_move && m_can_jump && control.jump))
	{
		// Jumping and falling
		if(superspeed || (fast_move && control.aux1))
			incH = movement_acceleration_fast * BS * dtime;
		else
			incH = movement_acceleration_air * BS * dtime;
		incV = 0; // No vertical acceleration in air
	}
	else if (superspeed || (is_climbing && fast_climb) || ((in_liquid || in_liquid_stable) && fast_climb))
		incH = incV = movement_acceleration_fast * BS * dtime;
	else
		incH = incV = movement_acceleration_default * BS * dtime;

	float slip_factor = getSlipFactor(env, speedH);
	// Accelerate to target speed with maximum increment
	accelerateHorizontal(speedH * physics_override_speed,
			incH * physics_override_speed * slip_factor);
	accelerateVertical(speedV * physics_override_speed,
			incV * physics_override_speed);
}

v3s16 LocalPlayer::getStandingNodePos()
{
	if(m_sneak_node_exists)
		return m_sneak_node;
	return m_standing_node;
}

v3s16 LocalPlayer::getFootstepNodePos()
{
	if (in_liquid_stable)
		// Emit swimming sound if the player is in liquid
		return floatToInt(getPosition(), BS);
	if (touching_ground)
		// BS * 0.05 below the player's feet ensures a 1/16th height
		// nodebox is detected instead of the node below it.
		return floatToInt(getPosition() - v3f(0, BS * 0.05f, 0), BS);
	// A larger distance below is necessary for a footstep sound
	// when landing after a jump or fall. BS * 0.5 ensures water
	// sounds when swimming in 1 node deep water.
	return floatToInt(getPosition() - v3f(0, BS * 0.5f, 0), BS);
}

v3s16 LocalPlayer::getLightPosition() const
{
	return floatToInt(m_position + v3f(0,BS+BS/2,0), BS);
}

v3f LocalPlayer::getEyeOffset() const
{
	float eye_height = camera_barely_in_ceiling ?
		m_eye_height - 0.125f : m_eye_height;
	return v3f(0, BS * eye_height, 0);
}

// Horizontal acceleration (X and Z), Y direction is ignored
void LocalPlayer::accelerateHorizontal(const v3f &target_speed,
	const f32 max_increase)
{
        if (max_increase == 0)
                return;

	v3f d_wanted = target_speed - m_speed;
	d_wanted.Y = 0.0f;
	f32 dl = d_wanted.getLength();
	if (dl > max_increase)
		dl = max_increase;

	v3f d = d_wanted.normalize() * dl;

	m_speed.X += d.X;
	m_speed.Z += d.Z;
}

// Vertical acceleration (Y), X and Z directions are ignored
void LocalPlayer::accelerateVertical(const v3f &target_speed, const f32 max_increase)
{
	if (max_increase == 0)
		return;

	f32 d_wanted = target_speed.Y - m_speed.Y;
	if (d_wanted > max_increase)
		d_wanted = max_increase;
	else if (d_wanted < -max_increase)
		d_wanted = -max_increase;

	m_speed.Y += d_wanted;
}

// Temporary option for old move code
void LocalPlayer::old_move(f32 dtime, Environment *env, f32 pos_max_d,
		std::vector<CollisionInfo> *collision_info)
{
	Map *map = &env->getMap();
	const NodeDefManager *nodemgr = m_client->ndef();

	v3f position = getPosition();

	// Copy parent position if local player is attached
	if (isAttached) {
		setPosition(overridePosition);
		m_sneak_node_exists = false;
		return;
	}

	// Skip collision detection if noclip mode is used
	bool fly_allowed = m_client->checkLocalPrivilege("fly");
	bool noclip = m_client->checkLocalPrivilege("noclip") &&
		g_settings->getBool("noclip");
	bool free_move = noclip && fly_allowed && g_settings->getBool("free_move");
	if (free_move) {
		position += m_speed * dtime;
		setPosition(position);
		m_sneak_node_exists = false;
		return;
	}

	/*
		Collision detection
	*/
	bool is_valid_position;
	MapNode node;
	v3s16 pp;

	/*
		Check if player is in liquid (the oscillating value)
	*/
	if (in_liquid) {
		// If in liquid, the threshold of coming out is at higher y
		pp = floatToInt(position + v3f(0, BS * 0.1, 0), BS);
		node = map->getNodeNoEx(pp, &is_valid_position);
		if (is_valid_position) {
			in_liquid = nodemgr->get(node.getContent()).isLiquid();
			liquid_viscosity = nodemgr->get(node.getContent()).liquid_viscosity;
		} else {
			in_liquid = false;
		}
	} else {
		// If not in liquid, the threshold of going in is at lower y
		pp = floatToInt(position + v3f(0, BS * 0.5, 0), BS);
		node = map->getNodeNoEx(pp, &is_valid_position);
		if (is_valid_position) {
			in_liquid = nodemgr->get(node.getContent()).isLiquid();
			liquid_viscosity = nodemgr->get(node.getContent()).liquid_viscosity;
		} else {
			in_liquid = false;
		}
	}

	/*
		Check if player is in liquid (the stable value)
	*/
	pp = floatToInt(position + v3f(0, 0, 0), BS);
	node = map->getNodeNoEx(pp, &is_valid_position);
	if (is_valid_position)
		in_liquid_stable = nodemgr->get(node.getContent()).isLiquid();
	else
		in_liquid_stable = false;

	/*
		Check if player is climbing
	*/
	pp = floatToInt(position + v3f(0, 0.5 * BS, 0), BS);
	v3s16 pp2 = floatToInt(position + v3f(0, -0.2 * BS, 0), BS);
	node = map->getNodeNoEx(pp, &is_valid_position);
	bool is_valid_position2;
	MapNode node2 = map->getNodeNoEx(pp2, &is_valid_position2);

	if (!(is_valid_position && is_valid_position2))
		is_climbing = false;
	else
		is_climbing = (nodemgr->get(node.getContent()).climbable ||
				nodemgr->get(node2.getContent()).climbable) && !free_move;

	/*
		Collision uncertainty radius
		Make it a bit larger than the maximum distance of movement
	*/
	//f32 d = pos_max_d * 1.1;
	// A fairly large value in here makes moving smoother
	f32 d = 0.15 * BS;
	// This should always apply, otherwise there are glitches
	sanity_check(d > pos_max_d);
	// Maximum distance over border for sneaking
	f32 sneak_max = BS * 0.4;

	/*
		If sneaking, keep in range from the last walked node and don't
		fall off from it
	*/
	if (control.sneak && m_sneak_node_exists &&
			!(fly_allowed && g_settings->getBool("free_move")) && !in_liquid &&
			physics_override_sneak) {
		f32 maxd = 0.5 * BS + sneak_max;
		v3f lwn_f = intToFloat(m_sneak_node, BS);
		position.X = rangelim(position.X, lwn_f.X - maxd, lwn_f.X + maxd);
		position.Z = rangelim(position.Z, lwn_f.Z - maxd, lwn_f.Z + maxd);

		if (!is_climbing) {
			// Move up if necessary
			f32 new_y = (lwn_f.Y - 0.5 * BS) + m_sneak_node_bb_ymax;
			if (position.Y < new_y)
				position.Y = new_y;
			/*
				Collision seems broken, since player is sinking when
				sneaking over the edges of current sneaking_node.
				TODO (when fixed): Set Y-speed only to 0 when position.Y < new_y.
			*/
			if (m_speed.Y < 0)
				m_speed.Y = 0;
		}
	}

	// this shouldn't be hardcoded but transmitted from server
	float player_stepheight = touching_ground ? (BS * 0.6) : (BS * 0.2);

#ifdef __ANDROID__
	player_stepheight += (0.6 * BS);
#endif

	v3f accel_f = v3f(0, 0, 0);

	collisionMoveResult result = collisionMoveSimple(env, m_client,
		pos_max_d, m_collisionbox, player_stepheight, dtime,
		&position, &m_speed, accel_f);

	/*
		If the player's feet touch the topside of any node, this is
		set to true.

		Player is allowed to jump when this is true.
	*/
	bool touching_ground_was = touching_ground;
	touching_ground = result.touching_ground;

    //bool standing_on_unloaded = result.standing_on_unloaded;

	/*
		Check the nodes under the player to see from which node the
		player is sneaking from, if any.  If the node from under
		the player has been removed, the player falls.
	*/
	f32 position_y_mod = 0.05 * BS;
	if (m_sneak_node_bb_ymax > 0)
		position_y_mod = m_sneak_node_bb_ymax - position_y_mod;
	v3s16 current_node = floatToInt(position - v3f(0, position_y_mod, 0), BS);
	if (m_sneak_node_exists &&
			nodemgr->get(map->getNodeNoEx(m_old_node_below)).name == "air" &&
			m_old_node_below_type != "air") {
		// Old node appears to have been removed; that is,
		// it wasn't air before but now it is
		m_need_to_get_new_sneak_node = false;
		m_sneak_node_exists = false;
	} else if (nodemgr->get(map->getNodeNoEx(current_node)).name != "air") {
		// We are on something, so make sure to recalculate the sneak
		// node.
		m_need_to_get_new_sneak_node = true;
	}

	if (m_need_to_get_new_sneak_node && physics_override_sneak) {
		m_sneak_node_bb_ymax = 0;
		v3s16 pos_i_bottom = floatToInt(position - v3f(0, position_y_mod, 0), BS);
		v2f player_p2df(position.X, position.Z);
		f32 min_distance_f = 100000.0 * BS;
		// If already seeking from some node, compare to it.
		v3s16 new_sneak_node = m_sneak_node;
		for (s16 x= -1; x <= 1; x++)
		for (s16 z= -1; z <= 1; z++) {
			v3s16 p = pos_i_bottom + v3s16(x, 0, z);
			v3f pf = intToFloat(p, BS);
			v2f node_p2df(pf.X, pf.Z);
			f32 distance_f = player_p2df.getDistanceFrom(node_p2df);
			f32 max_axis_distance_f = MYMAX(
					fabs(player_p2df.X - node_p2df.X),
					fabs(player_p2df.Y - node_p2df.Y));

			if (distance_f > min_distance_f ||
					max_axis_distance_f > 0.5 * BS + sneak_max + 0.1 * BS)
				continue;

			// The node to be sneaked on has to be walkable
			node = map->getNodeNoEx(p, &is_valid_position);
			if (!is_valid_position || !nodemgr->get(node).walkable)
				continue;
			// And the node above it has to be nonwalkable
			node = map->getNodeNoEx(p + v3s16(0, 1, 0), &is_valid_position);
			if (!is_valid_position || nodemgr->get(node).walkable)
				continue;
			// If not 'sneak_glitch' the node 2 nodes above it has to be nonwalkable
			if (!physics_override_sneak_glitch) {
				node =map->getNodeNoEx(p + v3s16(0, 2, 0), &is_valid_position);
				if (!is_valid_position || nodemgr->get(node).walkable)
					continue;
			}

			min_distance_f = distance_f;
			new_sneak_node = p;
		}

		bool sneak_node_found = (min_distance_f < 100000.0 * BS * 0.9);

		m_sneak_node = new_sneak_node;
		m_sneak_node_exists = sneak_node_found;

		if (sneak_node_found) {
			f32 cb_max = 0;
			MapNode n = map->getNodeNoEx(m_sneak_node);
			std::vector<aabb3f> nodeboxes;
			n.getCollisionBoxes(nodemgr, &nodeboxes);
			for (const auto &box : nodeboxes) {
				if (box.MaxEdge.Y > cb_max)
					cb_max = box.MaxEdge.Y;
			}
			m_sneak_node_bb_ymax = cb_max;
		}

		/*
			If sneaking, the player's collision box can be in air, so
			this has to be set explicitly
		*/
		if (sneak_node_found && control.sneak)
			touching_ground = true;
	}

	/*
		Set new position but keep sneak node set
	*/
	bool sneak_node_exists = m_sneak_node_exists;
	setPosition(position);
	m_sneak_node_exists = sneak_node_exists;

	/*
		Report collisions
	*/
	// Dont report if flying
	if (collision_info && !(g_settings->getBool("free_move") && fly_allowed)) {
		for (const auto &info : result.collisions) {
			collision_info->push_back(info);
		}
	}

	if (!result.standing_on_object && !touching_ground_was && touching_ground) {
		MtEvent *e = new SimpleTriggerEvent("PlayerRegainGround");
		m_client->event()->put(e);
		// Set camera impact value to be used for view bobbing
		camera_impact = getSpeed().Y * -1;
	}

	{
		camera_barely_in_ceiling = false;
		v3s16 camera_np = floatToInt(getEyePosition(), BS);
		MapNode n = map->getNodeNoEx(camera_np);
		if (n.getContent() != CONTENT_IGNORE) {
			if (nodemgr->get(n).walkable && nodemgr->get(n).solidness == 2)
				camera_barely_in_ceiling = true;
		}
	}

	/*
		Update the node last under the player
	*/
	m_old_node_below = floatToInt(position - v3f(0, BS / 2, 0), BS);
	m_old_node_below_type = nodemgr->get(map->getNodeNoEx(m_old_node_below)).name;

	/*
		Check properties of the node on which the player is standing
	*/
	const ContentFeatures &f = nodemgr->get(map->getNodeNoEx(getStandingNodePos()));
	// Determine if jumping is possible
	m_can_jump = touching_ground && !in_liquid;
	if (itemgroup_get(f.groups, "disable_jump"))
		m_can_jump = false;
	// Jump key pressed while jumping off from a bouncy block
	if (m_can_jump && control.jump && itemgroup_get(f.groups, "bouncy") &&
			m_speed.Y >= -0.5 * BS) {
		float jumpspeed = movement_speed_jump * physics_override_jump;
		if (m_speed.Y > 1) {
			// Reduce boost when speed already is high
			m_speed.Y += jumpspeed / (1 + (m_speed.Y / 16 ));
		} else {
			m_speed.Y += jumpspeed;
		}
		setSpeed(m_speed);
		m_can_jump = false;
	}
}

float LocalPlayer::getSlipFactor(Environment *env, const v3f &speedH)
{

	if (!touching_ground)
		return 1.0f;

	float slip_factor = 1.0f;
	// Slip on slippery nodes
	const NodeDefManager *nodemgr = env->getGameDef()->ndef();
	Map *map = &env->getMap();
	const ContentFeatures &f = nodemgr->get(map->getNodeNoEx(
			floatToInt(getPosition() - v3f(0, 0.05f * BS, 0), BS)));
	int slippery = 0;
	if (f.walkable) {
		slippery = itemgroup_get(f.groups, "slippery");
	} else if (is_slipping) {
		// slipping over an edge? Check surroundings for slippery nodes
		slippery = 2 << 16; // guard value, bigger than all realistic ones
		for (int z = 0; z <= 1; z++) {
			for (int x = 0; x <= 1; x++) {
				// this should cover all nodes surrounding player position
				v3f offset((x - 0.5f) * BS, 0.05f * BS, (z - 0.5f) * BS);
				const ContentFeatures &f2 = nodemgr->get(map->getNodeNoEx(
						floatToInt(getPosition() - offset, BS)));
				if (f2.walkable) {
					// find least slippery node we might be standing on
					int s = itemgroup_get(f2.groups, "slippery");
					if (s < slippery)
						slippery = s;
				}
			}
		}
		// without any hits, ignore slippery
		if (slippery >= (2 << 16))
			slippery = 0;
	}
	if (slippery >= 1) {
		if (speedH == v3f(0.0f)) {
			slippery = slippery * 2;
		}
		slip_factor = core::clamp(1.0f / (slippery + 1), 0.001f, 1.0f);
		is_slipping = true;
	} else {
		// remember this to avoid checking the edge case above too often
		is_slipping = false;
	}
	return slip_factor;
}