/*
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 "inventorymanager.h"
#include "log.h"
#include "environment.h"
#include "scripting_game.h"
#include "serverobject.h"
#include "main.h"  // for g_settings
#include "settings.h"
#include "craftdef.h"
#include "rollback_interface.h"
#include "strfnd.h"

#define PP(x) "("<<(x).X<<","<<(x).Y<<","<<(x).Z<<")"

#define PLAYER_TO_SA(p)   p->getEnv()->getScriptIface()

/*
	InventoryLocation
*/

std::string InventoryLocation::dump() const
{
	std::ostringstream os(std::ios::binary);
	serialize(os);
	return os.str();
}

void InventoryLocation::serialize(std::ostream &os) const
{
	switch(type){
	case InventoryLocation::UNDEFINED:
		os<<"undefined";
		break;
	case InventoryLocation::CURRENT_PLAYER:
		os<<"current_player";
		break;
	case InventoryLocation::PLAYER:
		os<<"player:"<<name;
		break;
	case InventoryLocation::NODEMETA:
		os<<"nodemeta:"<<p.X<<","<<p.Y<<","<<p.Z;
		break;
	case InventoryLocation::DETACHED:
		os<<"detached:"<<name;
		break;
	default:
		FATAL_ERROR("Unhandled inventory location type");
	}
}

void InventoryLocation::deSerialize(std::istream &is)
{
	std::string tname;
	std::getline(is, tname, ':');
	if(tname == "undefined")
	{
		type = InventoryLocation::UNDEFINED;
	}
	else if(tname == "current_player")
	{
		type = InventoryLocation::CURRENT_PLAYER;
	}
	else if(tname == "player")
	{
		type = InventoryLocation::PLAYER;
		std::getline(is, name, '\n');
	}
	else if(tname == "nodemeta")
	{
		type = InventoryLocation::NODEMETA;
		std::string pos;
		std::getline(is, pos, '\n');
		Strfnd fn(pos);
		p.X = stoi(fn.next(","));
		p.Y = stoi(fn.next(","));
		p.Z = stoi(fn.next(","));
	}
	else if(tname == "detached")
	{
		type = InventoryLocation::DETACHED;
		std::getline(is, name, '\n');
	}
	else
	{
		infostream<<"Unknown InventoryLocation type=\""<<tname<<"\""<<std::endl;
		throw SerializationError("Unknown InventoryLocation type");
	}
}

void InventoryLocation::deSerialize(std::string s)
{
	std::istringstream is(s, std::ios::binary);
	deSerialize(is);
}

/*
	InventoryAction
*/

InventoryAction * InventoryAction::deSerialize(std::istream &is)
{
	std::string type;
	std::getline(is, type, ' ');

	InventoryAction *a = NULL;

	if(type == "Move")
	{
		a = new IMoveAction(is);
	}
	else if(type == "Drop")
	{
		a = new IDropAction(is);
	}
	else if(type == "Craft")
	{
		a = new ICraftAction(is);
	}

	return a;
}

/*
	IMoveAction
*/

IMoveAction::IMoveAction(std::istream &is)
{
	std::string ts;

	std::getline(is, ts, ' ');
	count = stoi(ts);

	std::getline(is, ts, ' ');
	from_inv.deSerialize(ts);

	std::getline(is, from_list, ' ');

	std::getline(is, ts, ' ');
	from_i = stoi(ts);

	std::getline(is, ts, ' ');
	to_inv.deSerialize(ts);

	std::getline(is, to_list, ' ');

	std::getline(is, ts, ' ');
	to_i = stoi(ts);
}

void IMoveAction::apply(InventoryManager *mgr, ServerActiveObject *player, IGameDef *gamedef)
{
	Inventory *inv_from = mgr->getInventory(from_inv);
	Inventory *inv_to = mgr->getInventory(to_inv);
	
	if(!inv_from){
		infostream<<"IMoveAction::apply(): FAIL: source inventory not found: "
				<<"from_inv=\""<<from_inv.dump()<<"\""
				<<", to_inv=\""<<to_inv.dump()<<"\""<<std::endl;
		return;
	}
	if(!inv_to){
		infostream<<"IMoveAction::apply(): FAIL: destination inventory not found: "
				<<"from_inv=\""<<from_inv.dump()<<"\""
				<<", to_inv=\""<<to_inv.dump()<<"\""<<std::endl;
		return;
	}

	InventoryList *list_from = inv_from->getList(from_list);
	InventoryList *list_to = inv_to->getList(to_list);

	/*
		If a list doesn't exist or the source item doesn't exist
	*/
	if(!list_from){
		infostream<<"IMoveAction::apply(): FAIL: source list not found: "
				<<"from_inv=\""<<from_inv.dump()<<"\""
				<<", from_list=\""<<from_list<<"\""<<std::endl;
		return;
	}
	if(!list_to){
		infostream<<"IMoveAction::apply(): FAIL: destination list not found: "
				<<"to_inv=\""<<to_inv.dump()<<"\""
				<<", to_list=\""<<to_list<<"\""<<std::endl;
		return;
	}

	/*
		Do not handle rollback if both inventories are that of the same player
	*/
	bool ignore_rollback = (
		from_inv.type == InventoryLocation::PLAYER &&
		to_inv.type == InventoryLocation::PLAYER &&
		from_inv.name == to_inv.name);

	/*
		Collect information of endpoints
	*/

	int try_take_count = count;
	if(try_take_count == 0)
		try_take_count = list_from->getItem(from_i).count;

	int src_can_take_count = 0xffff;
	int dst_can_put_count = 0xffff;
	
	/* Query detached inventories */

	// Move occurs in the same detached inventory
	if(from_inv.type == InventoryLocation::DETACHED &&
			to_inv.type == InventoryLocation::DETACHED &&
			from_inv.name == to_inv.name)
	{
		src_can_take_count = PLAYER_TO_SA(player)->detached_inventory_AllowMove(
				from_inv.name, from_list, from_i,
				to_list, to_i, try_take_count, player);
		dst_can_put_count = src_can_take_count;
	}
	else
	{
		// Destination is detached
		if(to_inv.type == InventoryLocation::DETACHED)
		{
			ItemStack src_item = list_from->getItem(from_i);
			src_item.count = try_take_count;
			dst_can_put_count = PLAYER_TO_SA(player)->detached_inventory_AllowPut(
					to_inv.name, to_list, to_i, src_item, player);
		}
		// Source is detached
		if(from_inv.type == InventoryLocation::DETACHED)
		{
			ItemStack src_item = list_from->getItem(from_i);
			src_item.count = try_take_count;
			src_can_take_count = PLAYER_TO_SA(player)->detached_inventory_AllowTake(
					from_inv.name, from_list, from_i, src_item, player);
		}
	}

	/* Query node metadata inventories */

	// Both endpoints are nodemeta
	// Move occurs in the same nodemeta inventory
	if(from_inv.type == InventoryLocation::NODEMETA &&
			to_inv.type == InventoryLocation::NODEMETA &&
			from_inv.p == to_inv.p)
	{
		src_can_take_count = PLAYER_TO_SA(player)->nodemeta_inventory_AllowMove(
				from_inv.p, from_list, from_i,
				to_list, to_i, try_take_count, player);
		dst_can_put_count = src_can_take_count;
	}
	else
	{
		// Destination is nodemeta
		if(to_inv.type == InventoryLocation::NODEMETA)
		{
			ItemStack src_item = list_from->getItem(from_i);
			src_item.count = try_take_count;
			dst_can_put_count = PLAYER_TO_SA(player)->nodemeta_inventory_AllowPut(
					to_inv.p, to_list, to_i, src_item, player);
		}
		// Source is nodemeta
		if(from_inv.type == InventoryLocation::NODEMETA)
		{
			ItemStack src_item = list_from->getItem(from_i);
			src_item.count = try_take_count;
			src_can_take_count = PLAYER_TO_SA(player)->nodemeta_inventory_AllowTake(
					from_inv.p, from_list, from_i, src_item, player);
		}
	}

	int old_count = count;
	
	/* Modify count according to collected data */
	count = try_take_count;
	if(src_can_take_count != -1 && count > src_can_take_count)
		count = src_can_take_count;
	if(dst_can_put_count != -1 && count > dst_can_put_count)
		count = dst_can_put_count;
	/* Limit according to source item count */
	if(count > list_from->getItem(from_i).count)
		count = list_from->getItem(from_i).count;
	
	/* If no items will be moved, don't go further */
	if(count == 0)
	{
		infostream<<"IMoveAction::apply(): move was completely disallowed:"
				<<" count="<<old_count
				<<" from inv=\""<<from_inv.dump()<<"\""
				<<" list=\""<<from_list<<"\""
				<<" i="<<from_i
				<<" to inv=\""<<to_inv.dump()<<"\""
				<<" list=\""<<to_list<<"\""
				<<" i="<<to_i
				<<std::endl;
		return;
	}

	ItemStack src_item = list_from->getItem(from_i);
	src_item.count = count;
	ItemStack from_stack_was = list_from->getItem(from_i);
	ItemStack to_stack_was = list_to->getItem(to_i);

	/*
		Perform actual move

		If something is wrong (source item is empty, destination is the
		same as source), nothing happens
	*/
	list_from->moveItem(from_i, list_to, to_i, count);

	// If source is infinite, reset it's stack
	if(src_can_take_count == -1){
		// If destination stack is of different type and there are leftover
		// items, attempt to put the leftover items to a different place in the
		// destination inventory.
		// The client-side GUI will try to guess if this happens.
		if(from_stack_was.name != to_stack_was.name){
			for(u32 i=0; i<list_to->getSize(); i++){
				if(list_to->getItem(i).empty()){
					list_to->changeItem(i, to_stack_was);
					break;
				}
			}
		}
		list_from->deleteItem(from_i);
		list_from->addItem(from_i, from_stack_was);
	}
	// If destination is infinite, reset it's stack and take count from source
	if(dst_can_put_count == -1){
		list_to->deleteItem(to_i);
		list_to->addItem(to_i, to_stack_was);
		list_from->deleteItem(from_i);
		list_from->addItem(from_i, from_stack_was);
		list_from->takeItem(from_i, count);
	}

	infostream<<"IMoveAction::apply(): moved"
			<<" count="<<count
			<<" from inv=\""<<from_inv.dump()<<"\""
			<<" list=\""<<from_list<<"\""
			<<" i="<<from_i
			<<" to inv=\""<<to_inv.dump()<<"\""
			<<" list=\""<<to_list<<"\""
			<<" i="<<to_i
			<<std::endl;

	/*
		Record rollback information
	*/
	if(!ignore_rollback && gamedef->rollback())
	{
		IRollbackManager *rollback = gamedef->rollback();

		// If source is not infinite, record item take
		if(src_can_take_count != -1){
			RollbackAction action;
			std::string loc;
			{
				std::ostringstream os(std::ios::binary);
				from_inv.serialize(os);
				loc = os.str();
			}
			action.setModifyInventoryStack(loc, from_list, from_i, false,
					src_item);
			rollback->reportAction(action);
		}
		// If destination is not infinite, record item put
		if(dst_can_put_count != -1){
			RollbackAction action;
			std::string loc;
			{
				std::ostringstream os(std::ios::binary);
				to_inv.serialize(os);
				loc = os.str();
			}
			action.setModifyInventoryStack(loc, to_list, to_i, true,
					src_item);
			rollback->reportAction(action);
		}
	}

	/*
		Report move to endpoints
	*/
	
	/* Detached inventories */

	// Both endpoints are same detached
	if(from_inv.type == InventoryLocation::DETACHED &&
			to_inv.type == InventoryLocation::DETACHED &&
			from_inv.name == to_inv.name)
	{
		PLAYER_TO_SA(player)->detached_inventory_OnMove(
				from_inv.name, from_list, from_i,
				to_list, to_i, count, player);
	}
	else
	{
		// Destination is detached
		if(to_inv.type == InventoryLocation::DETACHED)
		{
			PLAYER_TO_SA(player)->detached_inventory_OnPut(
					to_inv.name, to_list, to_i, src_item, player);
		}
		// Source is detached
		if(from_inv.type == InventoryLocation::DETACHED)
		{
			PLAYER_TO_SA(player)->detached_inventory_OnTake(
					from_inv.name, from_list, from_i, src_item, player);
		}
	}

	/* Node metadata inventories */

	// Both endpoints are same nodemeta
	if(from_inv.type == InventoryLocation::NODEMETA &&
			to_inv.type == InventoryLocation::NODEMETA &&
			from_inv.p == to_inv.p)
	{
		PLAYER_TO_SA(player)->nodemeta_inventory_OnMove(
				from_inv.p, from_list, from_i,
				to_list, to_i, count, player);
	}
	else{
		// Destination is nodemeta
		if(to_inv.type == InventoryLocation::NODEMETA)
		{
			PLAYER_TO_SA(player)->nodemeta_inventory_OnPut(
					to_inv.p, to_list, to_i, src_item, player);
		}
		// Source is nodemeta
		else if(from_inv.type == InventoryLocation::NODEMETA)
		{
			PLAYER_TO_SA(player)->nodemeta_inventory_OnTake(
					from_inv.p, from_list, from_i, src_item, player);
		}
	}
	
	mgr->setInventoryModified(from_inv, false);
	if(inv_from != inv_to)
		mgr->setInventoryModified(to_inv, false);
}

void IMoveAction::clientApply(InventoryManager *mgr, IGameDef *gamedef)
{
	// Optional InventoryAction operation that is run on the client
	// to make lag less apparent.

	Inventory *inv_from = mgr->getInventory(from_inv);
	Inventory *inv_to = mgr->getInventory(to_inv);
	if(!inv_from || !inv_to)
		return;

	InventoryLocation current_player;
	current_player.setCurrentPlayer();
	Inventory *inv_player = mgr->getInventory(current_player);
	if(inv_from != inv_player || inv_to != inv_player)
		return;

	InventoryList *list_from = inv_from->getList(from_list);
	InventoryList *list_to = inv_to->getList(to_list);
	if(!list_from || !list_to)
		return;

	list_from->moveItem(from_i, list_to, to_i, count);

	mgr->setInventoryModified(from_inv);
	if(inv_from != inv_to)
		mgr->setInventoryModified(to_inv);
}

/*
	IDropAction
*/

IDropAction::IDropAction(std::istream &is)
{
	std::string ts;

	std::getline(is, ts, ' ');
	count = stoi(ts);

	std::getline(is, ts, ' ');
	from_inv.deSerialize(ts);

	std::getline(is, from_list, ' ');

	std::getline(is, ts, ' ');
	from_i = stoi(ts);
}

void IDropAction::apply(InventoryManager *mgr, ServerActiveObject *player, IGameDef *gamedef)
{
	Inventory *inv_from = mgr->getInventory(from_inv);
	
	if(!inv_from){
		infostream<<"IDropAction::apply(): FAIL: source inventory not found: "
				<<"from_inv=\""<<from_inv.dump()<<"\""<<std::endl;
		return;
	}

	InventoryList *list_from = inv_from->getList(from_list);

	/*
		If a list doesn't exist or the source item doesn't exist
	*/
	if(!list_from){
		infostream<<"IDropAction::apply(): FAIL: source list not found: "
				<<"from_inv=\""<<from_inv.dump()<<"\""<<std::endl;
		return;
	}
	if(list_from->getItem(from_i).empty())
	{
		infostream<<"IDropAction::apply(): FAIL: source item not found: "
				<<"from_inv=\""<<from_inv.dump()<<"\""
				<<", from_list=\""<<from_list<<"\""
				<<" from_i="<<from_i<<std::endl;
		return;
	}

	/*
		Do not handle rollback if inventory is player's
	*/
	bool ignore_src_rollback = (from_inv.type == InventoryLocation::PLAYER);

	/*
		Collect information of endpoints
	*/

	int take_count = list_from->getItem(from_i).count;
	if(count != 0 && count < take_count)
		take_count = count;
	int src_can_take_count = take_count;

	// Source is detached
	if(from_inv.type == InventoryLocation::DETACHED)
	{
		ItemStack src_item = list_from->getItem(from_i);
		src_item.count = take_count;
		src_can_take_count = PLAYER_TO_SA(player)->detached_inventory_AllowTake(
				from_inv.name, from_list, from_i, src_item, player);
	}

	// Source is nodemeta
	if(from_inv.type == InventoryLocation::NODEMETA)
	{
		ItemStack src_item = list_from->getItem(from_i);
		src_item.count = take_count;
		src_can_take_count = PLAYER_TO_SA(player)->nodemeta_inventory_AllowTake(
				from_inv.p, from_list, from_i, src_item, player);
	}

	if(src_can_take_count != -1 && src_can_take_count < take_count)
		take_count = src_can_take_count;
	
	int actually_dropped_count = 0;

	ItemStack src_item = list_from->getItem(from_i);

	// Drop the item
	ItemStack item1 = list_from->getItem(from_i);
	item1.count = take_count;
	if(PLAYER_TO_SA(player)->item_OnDrop(item1, player,
				player->getBasePosition() + v3f(0,1,0)))
	{
		actually_dropped_count = take_count - item1.count;

		if(actually_dropped_count == 0){
			infostream<<"Actually dropped no items"<<std::endl;
			return;
		}
		
		// If source isn't infinite
		if(src_can_take_count != -1){
			// Take item from source list
			ItemStack item2 = list_from->takeItem(from_i, actually_dropped_count);

			if(item2.count != actually_dropped_count)
				errorstream<<"Could not take dropped count of items"<<std::endl;

			mgr->setInventoryModified(from_inv, false);
		}
	}

	infostream<<"IDropAction::apply(): dropped "
			<<" from inv=\""<<from_inv.dump()<<"\""
			<<" list=\""<<from_list<<"\""
			<<" i="<<from_i
			<<std::endl;
	
	src_item.count = actually_dropped_count;

	/*
		Report drop to endpoints
	*/
	
	// Source is detached
	if(from_inv.type == InventoryLocation::DETACHED)
	{
		PLAYER_TO_SA(player)->detached_inventory_OnTake(
				from_inv.name, from_list, from_i, src_item, player);
	}

	// Source is nodemeta
	if(from_inv.type == InventoryLocation::NODEMETA)
	{
		PLAYER_TO_SA(player)->nodemeta_inventory_OnTake(
				from_inv.p, from_list, from_i, src_item, player);
	}

	/*
		Record rollback information
	*/
	if(!ignore_src_rollback && gamedef->rollback())
	{
		IRollbackManager *rollback = gamedef->rollback();

		// If source is not infinite, record item take
		if(src_can_take_count != -1){
			RollbackAction action;
			std::string loc;
			{
				std::ostringstream os(std::ios::binary);
				from_inv.serialize(os);
				loc = os.str();
			}
			action.setModifyInventoryStack(loc, from_list, from_i,
					false, src_item);
			rollback->reportAction(action);
		}
	}
}

void IDropAction::clientApply(InventoryManager *mgr, IGameDef *gamedef)
{
	// Optional InventoryAction operation that is run on the client
	// to make lag less apparent.

	Inventory *inv_from = mgr->getInventory(from_inv);
	if(!inv_from)
		return;

	InventoryLocation current_player;
	current_player.setCurrentPlayer();
	Inventory *inv_player = mgr->getInventory(current_player);
	if(inv_from != inv_player)
		return;

	InventoryList *list_from = inv_from->getList(from_list);
	if(!list_from)
		return;

	if(count == 0)
		list_from->changeItem(from_i, ItemStack());
	else
		list_from->takeItem(from_i, count);

	mgr->setInventoryModified(from_inv);
}

/*
	ICraftAction
*/

ICraftAction::ICraftAction(std::istream &is)
{
	std::string ts;

	std::getline(is, ts, ' ');
	count = stoi(ts);

	std::getline(is, ts, ' ');
	craft_inv.deSerialize(ts);
}

void ICraftAction::apply(InventoryManager *mgr, ServerActiveObject *player, IGameDef *gamedef)
{
	Inventory *inv_craft = mgr->getInventory(craft_inv);
	
	if(!inv_craft){
		infostream<<"ICraftAction::apply(): FAIL: inventory not found: "
				<<"craft_inv=\""<<craft_inv.dump()<<"\""<<std::endl;
		return;
	}

	InventoryList *list_craft = inv_craft->getList("craft");
	InventoryList *list_craftresult = inv_craft->getList("craftresult");

	/*
		If a list doesn't exist or the source item doesn't exist
	*/
	if(!list_craft){
		infostream<<"ICraftAction::apply(): FAIL: craft list not found: "
				<<"craft_inv=\""<<craft_inv.dump()<<"\""<<std::endl;
		return;
	}
	if(!list_craftresult){
		infostream<<"ICraftAction::apply(): FAIL: craftresult list not found: "
				<<"craft_inv=\""<<craft_inv.dump()<<"\""<<std::endl;
		return;
	}
	if(list_craftresult->getSize() < 1){
		infostream<<"ICraftAction::apply(): FAIL: craftresult list too short: "
				<<"craft_inv=\""<<craft_inv.dump()<<"\""<<std::endl;
		return;
	}

	ItemStack crafted;
	ItemStack craftresultitem;
	int count_remaining = count;
	getCraftingResult(inv_craft, crafted, false, gamedef);
	PLAYER_TO_SA(player)->item_CraftPredict(crafted, player, list_craft, craft_inv);
	bool found = !crafted.empty();

	while(found && list_craftresult->itemFits(0, crafted))
	{
		InventoryList saved_craft_list = *list_craft;
		
		// Decrement input and add crafting output
		getCraftingResult(inv_craft, crafted, true, gamedef);
		PLAYER_TO_SA(player)->item_OnCraft(crafted, player, &saved_craft_list, craft_inv);
		list_craftresult->addItem(0, crafted);
		mgr->setInventoryModified(craft_inv);

		actionstream<<player->getDescription()
				<<" crafts "
				<<crafted.getItemString()
				<<std::endl;

		// Decrement counter
		if(count_remaining == 1)
			break;
		else if(count_remaining > 1)
			count_remaining--;

		// Get next crafting result
		found = getCraftingResult(inv_craft, crafted, false, gamedef);
		PLAYER_TO_SA(player)->item_CraftPredict(crafted, player, list_craft, craft_inv);
		found = !crafted.empty();
	}

	infostream<<"ICraftAction::apply(): crafted "
			<<" craft_inv=\""<<craft_inv.dump()<<"\""
			<<std::endl;
}

void ICraftAction::clientApply(InventoryManager *mgr, IGameDef *gamedef)
{
	// Optional InventoryAction operation that is run on the client
	// to make lag less apparent.
}


// Crafting helper
bool getCraftingResult(Inventory *inv, ItemStack& result,
		bool decrementInput, IGameDef *gamedef)
{
	DSTACK(__FUNCTION_NAME);
	
	result.clear();

	// Get the InventoryList in which we will operate
	InventoryList *clist = inv->getList("craft");
	if(!clist)
		return false;

	// Mangle crafting grid to an another format
	CraftInput ci;
	ci.method = CRAFT_METHOD_NORMAL;
	ci.width = clist->getWidth() ? clist->getWidth() : 3;
	for(u16 i=0; i<clist->getSize(); i++)
		ci.items.push_back(clist->getItem(i));

	// Find out what is crafted and add it to result item slot
	CraftOutput co;
	bool found = gamedef->getCraftDefManager()->getCraftResult(
			ci, co, decrementInput, gamedef);
	if(found)
		result.deSerialize(co.item, gamedef->getItemDefManager());

	if(found && decrementInput)
	{
		// CraftInput has been changed, apply changes in clist
		for(u16 i=0; i<clist->getSize(); i++)
		{
			clist->changeItem(i, ci.items[i]);
		}
	}

	return found;
}