/*
Minetest-c55
Copyright (C) 2010-2011 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 General Public License as published by
the Free Software Foundation; either version 2 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 General Public License for more details.

You should have received a copy of the GNU 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 "content_sao.h"
#include "collision.h"
#include "environment.h"
#include "settings.h"
#include "main.h" // For g_profiler
#include "profiler.h"
#include "serialization.h" // For compressZlib
#include "tool.h" // For ToolCapabilities
#include "gamedef.h"

core::map<u16, ServerActiveObject::Factory> ServerActiveObject::m_types;

/*
	DummyLoadSAO
*/

class DummyLoadSAO : public ServerActiveObject
{
public:
	DummyLoadSAO(ServerEnvironment *env, v3f pos, u8 type):
		ServerActiveObject(env, pos)
	{
		ServerActiveObject::registerType(type, create);
	}
	// Pretend to be the test object (to fool the client)
	u8 getType() const
	{ return ACTIVEOBJECT_TYPE_TEST; }
	// And never save to disk
	bool isStaticAllowed() const
	{ return false; }
	
	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
			const std::string &data)
	{
		return new DummyLoadSAO(env, pos, 0);
	}

	void step(float dtime, bool send_recommended)
	{
		m_removed = true;
		infostream<<"DummyLoadSAO step"<<std::endl;
	}

private:
};

// Prototype (registers item for deserialization)
DummyLoadSAO proto1_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_RAT);
DummyLoadSAO proto2_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_OERKKI1);
DummyLoadSAO proto3_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_FIREFLY);
DummyLoadSAO proto4_DummyLoadSAO(NULL, v3f(0,0,0), ACTIVEOBJECT_TYPE_MOBV2);

/*
	TestSAO
*/

class TestSAO : public ServerActiveObject
{
public:
	TestSAO(ServerEnvironment *env, v3f pos):
		ServerActiveObject(env, pos),
		m_timer1(0),
		m_age(0)
	{
		ServerActiveObject::registerType(getType(), create);
	}
	u8 getType() const
	{ return ACTIVEOBJECT_TYPE_TEST; }
	
	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
			const std::string &data)
	{
		return new TestSAO(env, pos);
	}

	void step(float dtime, bool send_recommended)
	{
		m_age += dtime;
		if(m_age > 10)
		{
			m_removed = true;
			return;
		}

		m_base_position.Y += dtime * BS * 2;
		if(m_base_position.Y > 8*BS)
			m_base_position.Y = 2*BS;

		if(send_recommended == false)
			return;

		m_timer1 -= dtime;
		if(m_timer1 < 0.0)
		{
			m_timer1 += 0.125;

			std::string data;

			data += itos(0); // 0 = position
			data += " ";
			data += itos(m_base_position.X);
			data += " ";
			data += itos(m_base_position.Y);
			data += " ";
			data += itos(m_base_position.Z);

			ActiveObjectMessage aom(getId(), false, data);
			m_messages_out.push_back(aom);
		}
	}

private:
	float m_timer1;
	float m_age;
};

// Prototype (registers item for deserialization)
TestSAO proto_TestSAO(NULL, v3f(0,0,0));

/*
	ItemSAO
*/

class ItemSAO : public ServerActiveObject
{
public:
	u8 getType() const
	{ return ACTIVEOBJECT_TYPE_ITEM; }
	
	float getMinimumSavedMovement()
	{ return 0.1*BS; }

	static ServerActiveObject* create(ServerEnvironment *env, v3f pos,
			const std::string &data)
	{
		std::istringstream is(data, std::ios::binary);
		char buf[1];
		// read version
		is.read(buf, 1);
		u8 version = buf[0];
		// check if version is supported
		if(version != 0)
			return NULL;
		std::string itemstring = deSerializeString(is);
		infostream<<"create(): Creating item \""
				<<itemstring<<"\""<<std::endl;
		return new ItemSAO(env, pos, itemstring);
	}

	ItemSAO(ServerEnvironment *env, v3f pos,
			const std::string itemstring):
		ServerActiveObject(env, pos),
		m_itemstring(itemstring),
		m_itemstring_changed(false),
		m_speed_f(0,0,0),
		m_last_sent_position(0,0,0)
	{
		ServerActiveObject::registerType(getType(), create);
	}

	void step(float dtime, bool send_recommended)
	{
		ScopeProfiler sp2(g_profiler, "step avg", SPT_AVG);

		assert(m_env);

		const float interval = 0.2;
		if(m_move_interval.step(dtime, interval)==false)
			return;
		dtime = interval;
		
		core::aabbox3d<f32> box(-BS/3.,0.0,-BS/3., BS/3.,BS*2./3.,BS/3.);
		collisionMoveResult moveresult;
		// Apply gravity
		m_speed_f += v3f(0, -dtime*9.81*BS, 0);
		// Maximum movement without glitches
		f32 pos_max_d = BS*0.25;
		// Limit speed
		if(m_speed_f.getLength()*dtime > pos_max_d)
			m_speed_f *= pos_max_d / (m_speed_f.getLength()*dtime);
		v3f pos_f = getBasePosition();
		v3f pos_f_old = pos_f;
		IGameDef *gamedef = m_env->getGameDef();
		moveresult = collisionMoveSimple(&m_env->getMap(), gamedef,
				pos_max_d, box, dtime, pos_f, m_speed_f);
		
		if(send_recommended == false)
			return;

		if(pos_f.getDistanceFrom(m_last_sent_position) > 0.05*BS)
		{
			setBasePosition(pos_f);
			m_last_sent_position = pos_f;

			std::ostringstream os(std::ios::binary);
			// command (0 = update position)
			writeU8(os, 0);
			// pos
			writeV3F1000(os, m_base_position);
			// create message and add to list
			ActiveObjectMessage aom(getId(), false, os.str());
			m_messages_out.push_back(aom);
		}
		if(m_itemstring_changed)
		{
			m_itemstring_changed = false;

			std::ostringstream os(std::ios::binary);
			// command (1 = update itemstring)
			writeU8(os, 1);
			// itemstring
			os<<serializeString(m_itemstring);
			// create message and add to list
			ActiveObjectMessage aom(getId(), false, os.str());
			m_messages_out.push_back(aom);
		}
	}

	std::string getClientInitializationData()
	{
		std::ostringstream os(std::ios::binary);
		// version
		writeU8(os, 0);
		// pos
		writeV3F1000(os, m_base_position);
		// itemstring
		os<<serializeString(m_itemstring);
		return os.str();
	}

	std::string getStaticData()
	{
		infostream<<__FUNCTION_NAME<<std::endl;
		std::ostringstream os(std::ios::binary);
		// version
		writeU8(os, 0);
		// itemstring
		os<<serializeString(m_itemstring);
		return os.str();
	}

	ItemStack createItemStack()
	{
		try{
			IItemDefManager *idef = m_env->getGameDef()->idef();
			ItemStack item;
			item.deSerialize(m_itemstring, idef);
			infostream<<__FUNCTION_NAME<<": m_itemstring=\""<<m_itemstring
					<<"\" -> item=\""<<item.getItemString()<<"\""
					<<std::endl;
			return item;
		}
		catch(SerializationError &e)
		{
			infostream<<__FUNCTION_NAME<<": serialization error: "
					<<"m_itemstring=\""<<m_itemstring<<"\""<<std::endl;
			return ItemStack();
		}
	}

	int punch(v3f dir,
			const ToolCapabilities *toolcap,
			ServerActiveObject *puncher,
			float time_from_last_punch)
	{
		// Directly delete item in creative mode
		if(g_settings->getBool("creative_mode") == true)
		{
			m_removed = true;
			return 0;
		}
		
		// Take item into inventory
		ItemStack item = createItemStack();
		Inventory *inv = puncher->getInventory();
		if(inv != NULL)
		{
			std::string wieldlist = puncher->getWieldList();
			ItemStack leftover = inv->addItem(wieldlist, item);
			puncher->setInventoryModified();
			if(leftover.empty())
			{
				m_removed = true;
			}
			else
			{
				m_itemstring = leftover.getItemString();
				m_itemstring_changed = true;
			}
		}
		
		return 0;
	}


private:
	std::string m_itemstring;
	bool m_itemstring_changed;
	v3f m_speed_f;
	v3f m_last_sent_position;
	IntervalLimiter m_move_interval;
};

// Prototype (registers item for deserialization)
ItemSAO proto_ItemSAO(NULL, v3f(0,0,0), "");

ServerActiveObject* createItemSAO(ServerEnvironment *env, v3f pos,
		const std::string itemstring)
{
	return new ItemSAO(env, pos, itemstring);
}

/*
	LuaEntitySAO
*/

#include "scriptapi.h"
#include "luaentity_common.h"

// Prototype (registers item for deserialization)
LuaEntitySAO proto_LuaEntitySAO(NULL, v3f(0,0,0), "_prototype", "");

LuaEntitySAO::LuaEntitySAO(ServerEnvironment *env, v3f pos,
		const std::string &name, const std::string &state):
	ServerActiveObject(env, pos),
	m_init_name(name),
	m_init_state(state),
	m_registered(false),
	m_prop(new LuaEntityProperties),
	m_hp(-1),
	m_velocity(0,0,0),
	m_acceleration(0,0,0),
	m_yaw(0),
	m_last_sent_yaw(0),
	m_last_sent_position(0,0,0),
	m_last_sent_velocity(0,0,0),
	m_last_sent_position_timer(0),
	m_last_sent_move_precision(0),
	m_armor_groups_sent(false)
{
	// Only register type if no environment supplied
	if(env == NULL){
		ServerActiveObject::registerType(getType(), create);
		return;
	}
	
	// Initialize something to armor groups
	m_armor_groups["fleshy"] = 3;
	m_armor_groups["snappy"] = 2;
}

LuaEntitySAO::~LuaEntitySAO()
{
	if(m_registered){
		lua_State *L = m_env->getLua();
		scriptapi_luaentity_rm(L, m_id);
	}
	delete m_prop;
}

void LuaEntitySAO::addedToEnvironment()
{
	ServerActiveObject::addedToEnvironment();
	
	// Create entity from name
	lua_State *L = m_env->getLua();
	m_registered = scriptapi_luaentity_add(L, m_id, m_init_name.c_str());
	
	if(m_registered){
		// Get properties
		scriptapi_luaentity_get_properties(L, m_id, m_prop);
		// Initialize HP from properties
		m_hp = m_prop->hp_max;
	}
	
	// Activate entity, supplying serialized state
	scriptapi_luaentity_activate(L, m_id, m_init_state.c_str());
}

ServerActiveObject* LuaEntitySAO::create(ServerEnvironment *env, v3f pos,
		const std::string &data)
{
	std::string name;
	std::string state;
	s16 hp = 1;
	v3f velocity;
	float yaw = 0;
	if(data != ""){
		std::istringstream is(data, std::ios::binary);
		// read version
		u8 version = readU8(is);
		// check if version is supported
		if(version == 0){
			name = deSerializeString(is);
			state = deSerializeLongString(is);
		}
		else if(version == 1){
			name = deSerializeString(is);
			state = deSerializeLongString(is);
			hp = readS16(is);
			velocity = readV3F1000(is);
			yaw = readF1000(is);
		}
	}
	// create object
	infostream<<"LuaEntitySAO::create(name=\""<<name<<"\" state=\""
			<<state<<"\")"<<std::endl;
	LuaEntitySAO *sao = new LuaEntitySAO(env, pos, name, state);
	sao->m_hp = hp;
	sao->m_velocity = velocity;
	sao->m_yaw = yaw;
	return sao;
}

void LuaEntitySAO::step(float dtime, bool send_recommended)
{
	m_last_sent_position_timer += dtime;
	
	if(m_prop->physical){
		core::aabbox3d<f32> box = m_prop->collisionbox;
		box.MinEdge *= BS;
		box.MaxEdge *= BS;
		collisionMoveResult moveresult;
		f32 pos_max_d = BS*0.25; // Distance per iteration
		v3f p_pos = getBasePosition();
		v3f p_velocity = m_velocity;
		IGameDef *gamedef = m_env->getGameDef();
		moveresult = collisionMovePrecise(&m_env->getMap(), gamedef,
				pos_max_d, box, dtime, p_pos, p_velocity);
		// Apply results
		setBasePosition(p_pos);
		m_velocity = p_velocity;

		m_velocity += dtime * m_acceleration;
	} else {
		m_base_position += dtime * m_velocity + 0.5 * dtime
				* dtime * m_acceleration;
		m_velocity += dtime * m_acceleration;
	}

	if(m_registered){
		lua_State *L = m_env->getLua();
		scriptapi_luaentity_step(L, m_id, dtime);
	}

	if(send_recommended == false)
		return;
	
	// TODO: force send when acceleration changes enough?
	float minchange = 0.2*BS;
	if(m_last_sent_position_timer > 1.0){
		minchange = 0.01*BS;
	} else if(m_last_sent_position_timer > 0.2){
		minchange = 0.05*BS;
	}
	float move_d = m_base_position.getDistanceFrom(m_last_sent_position);
	move_d += m_last_sent_move_precision;
	float vel_d = m_velocity.getDistanceFrom(m_last_sent_velocity);
	if(move_d > minchange || vel_d > minchange ||
			fabs(m_yaw - m_last_sent_yaw) > 1.0){
		sendPosition(true, false);
	}

	if(m_armor_groups_sent == false){
		m_armor_groups_sent = true;
		std::ostringstream os(std::ios::binary);
		writeU8(os, LUAENTITY_CMD_UPDATE_ARMOR_GROUPS);
		writeU16(os, m_armor_groups.size());
		for(ItemGroupList::const_iterator i = m_armor_groups.begin();
				i != m_armor_groups.end(); i++){
			os<<serializeString(i->first);
			writeS16(os, i->second);
		}
		// create message and add to list
		ActiveObjectMessage aom(getId(), true, os.str());
		m_messages_out.push_back(aom);
	}
}

std::string LuaEntitySAO::getClientInitializationData()
{
	std::ostringstream os(std::ios::binary);
	// version
	writeU8(os, 1);
	// pos
	writeV3F1000(os, m_base_position);
	// yaw
	writeF1000(os, m_yaw);
	// hp
	writeS16(os, m_hp);
	// properties
	std::ostringstream prop_os(std::ios::binary);
	m_prop->serialize(prop_os);
	os<<serializeLongString(prop_os.str());
	// return result
	return os.str();
}

std::string LuaEntitySAO::getStaticData()
{
	verbosestream<<__FUNCTION_NAME<<std::endl;
	std::ostringstream os(std::ios::binary);
	// version
	writeU8(os, 1);
	// name
	os<<serializeString(m_init_name);
	// state
	if(m_registered){
		lua_State *L = m_env->getLua();
		std::string state = scriptapi_luaentity_get_staticdata(L, m_id);
		os<<serializeLongString(state);
	} else {
		os<<serializeLongString(m_init_state);
	}
	// hp
	writeS16(os, m_hp);
	// velocity
	writeV3F1000(os, m_velocity);
	// yaw
	writeF1000(os, m_yaw);
	return os.str();
}

int LuaEntitySAO::punch(v3f dir,
		const ToolCapabilities *toolcap,
		ServerActiveObject *puncher,
		float time_from_last_punch)
{
	if(!m_registered){
		// Delete unknown LuaEntities when punched
		m_removed = true;
		return 0;
	}
	
	ItemStack *punchitem = NULL;
	ItemStack punchitem_static;
	if(puncher){
		punchitem_static = puncher->getWieldedItem();
		punchitem = &punchitem_static;
	}

	PunchDamageResult result = getPunchDamage(
			m_armor_groups,
			toolcap,
			punchitem,
			time_from_last_punch);
	
	if(result.did_punch)
	{
		setHP(getHP() - result.damage);
		
		actionstream<<getDescription()<<" punched by "
				<<puncher->getDescription()<<", damage "<<result.damage
				<<" hp, health now "<<getHP()<<" hp"<<std::endl;
		
		{
			std::ostringstream os(std::ios::binary);
			// command 
			writeU8(os, LUAENTITY_CMD_PUNCHED);
			// damage
			writeS16(os, result.damage);
			// result_hp
			writeS16(os, getHP());
			// create message and add to list
			ActiveObjectMessage aom(getId(), true, os.str());
			m_messages_out.push_back(aom);
		}

		if(getHP() == 0)
			m_removed = true;
	}

	lua_State *L = m_env->getLua();
	scriptapi_luaentity_punch(L, m_id, puncher,
			time_from_last_punch, toolcap, dir);

	return result.wear;
}

void LuaEntitySAO::rightClick(ServerActiveObject *clicker)
{
	if(!m_registered)
		return;
	lua_State *L = m_env->getLua();
	scriptapi_luaentity_rightclick(L, m_id, clicker);
}

void LuaEntitySAO::setHP(s16 hp)
{
	if(hp < 0) hp = 0;
	m_hp = hp;
}

s16 LuaEntitySAO::getHP()
{
	return m_hp;
}

void LuaEntitySAO::setPos(v3f pos)
{
	m_base_position = pos;
	sendPosition(false, true);
}

void LuaEntitySAO::moveTo(v3f pos, bool continuous)
{
	m_base_position = pos;
	if(!continuous)
		sendPosition(true, true);
}

float LuaEntitySAO::getMinimumSavedMovement()
{
	return 0.1 * BS;
}

std::string LuaEntitySAO::getDescription()
{
	std::ostringstream os(std::ios::binary);
	os<<"LuaEntitySAO at (";
	os<<(m_base_position.X/BS)<<",";
	os<<(m_base_position.Y/BS)<<",";
	os<<(m_base_position.Z/BS);
	os<<")";
	return os.str();
}

void LuaEntitySAO::setVelocity(v3f velocity)
{
	m_velocity = velocity;
}

v3f LuaEntitySAO::getVelocity()
{
	return m_velocity;
}

void LuaEntitySAO::setAcceleration(v3f acceleration)
{
	m_acceleration = acceleration;
}

v3f LuaEntitySAO::getAcceleration()
{
	return m_acceleration;
}

void LuaEntitySAO::setYaw(float yaw)
{
	m_yaw = yaw;
}

float LuaEntitySAO::getYaw()
{
	return m_yaw;
}

void LuaEntitySAO::setTextureMod(const std::string &mod)
{
	std::ostringstream os(std::ios::binary);
	// command 
	writeU8(os, LUAENTITY_CMD_SET_TEXTURE_MOD);
	// parameters
	os<<serializeString(mod);
	// create message and add to list
	ActiveObjectMessage aom(getId(), false, os.str());
	m_messages_out.push_back(aom);
}

void LuaEntitySAO::setSprite(v2s16 p, int num_frames, float framelength,
		bool select_horiz_by_yawpitch)
{
	std::ostringstream os(std::ios::binary);
	// command
	writeU8(os, LUAENTITY_CMD_SET_SPRITE);
	// parameters
	writeV2S16(os, p);
	writeU16(os, num_frames);
	writeF1000(os, framelength);
	writeU8(os, select_horiz_by_yawpitch);
	// create message and add to list
	ActiveObjectMessage aom(getId(), false, os.str());
	m_messages_out.push_back(aom);
}

std::string LuaEntitySAO::getName()
{
	return m_init_name;
}

void LuaEntitySAO::setArmorGroups(const ItemGroupList &armor_groups)
{
	m_armor_groups = armor_groups;
	m_armor_groups_sent = false;
}

void LuaEntitySAO::sendPosition(bool do_interpolate, bool is_movement_end)
{
	m_last_sent_move_precision = m_base_position.getDistanceFrom(
			m_last_sent_position);
	m_last_sent_position_timer = 0;
	m_last_sent_yaw = m_yaw;
	m_last_sent_position = m_base_position;
	m_last_sent_velocity = m_velocity;
	//m_last_sent_acceleration = m_acceleration;

	float update_interval = m_env->getSendRecommendedInterval();

	std::ostringstream os(std::ios::binary);
	// command
	writeU8(os, LUAENTITY_CMD_UPDATE_POSITION);

	// do_interpolate
	writeU8(os, do_interpolate);
	// pos
	writeV3F1000(os, m_base_position);
	// velocity
	writeV3F1000(os, m_velocity);
	// acceleration
	writeV3F1000(os, m_acceleration);
	// yaw
	writeF1000(os, m_yaw);
	// is_end_position (for interpolation)
	writeU8(os, is_movement_end);
	// update_interval (for interpolation)
	writeF1000(os, update_interval);

	// create message and add to list
	ActiveObjectMessage aom(getId(), false, os.str());
	m_messages_out.push_back(aom);
}