/*
 *   ORXONOX - the hottest 3D action shooter ever to exist
 *                    > www.orxonox.net <
 *
 *
 *   License notice:
 *
 *   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.
 *
 *   Author:
 *      Damian 'Mozork' Frick
 *   Co-authors:
 *      ...
 *
*/

/**
    @file PickupManager.cc
    @brief Implementation of the PickupManager class.
*/

#include "PickupManager.h"

#include "core/CoreIncludes.h"
#include "core/LuaState.h"
#include "core/GUIManager.h"
#include "core/class/Identifier.h"
#include "core/singleton/ScopedSingletonIncludes.h"
#include "network/Host.h"
#include "network/NetworkFunctionIncludes.h"
#include "core/input/KeyBinderManager.h"    //for keybinding
#include "core/input/KeyBinder.h"           //for keybinding
#include "core/command/ConsoleCommandIncludes.h"

#include "infos/PlayerInfo.h"
#include "interfaces/PickupCarrier.h"
#include "worldentities/pawns/Pawn.h"

#include "CollectiblePickup.h"
#include "PickupRepresentation.h"
#include "overlays/hud/HUDPickupSystem.h"

namespace orxonox
{
    ManageScopedSingleton(PickupManager, ScopeID::ROOT, false);

    // Initialization of the name of the PickupInventory GUI.
    /*static*/ const std::string PickupManager::guiName_s = "PickupInventory";

    // Register static network functions that are used to communicate changes to pickups over the network, such that the PickupInventory can display the information about the pickups properly.
    registerStaticNetworkFunction(PickupManager::pickupChangedUsedNetwork);
    registerStaticNetworkFunction(PickupManager::pickupChangedPickedUpNetwork);
    registerStaticNetworkFunction(PickupManager::dropPickupNetworked);
    registerStaticNetworkFunction(PickupManager::usePickupNetworked);

    RegisterAbstractClass(PickupManager).inheritsFrom<PickupListener>();

    SetConsoleCommand("useUnusePickup", &PickupManager::useUnusePickup).addShortcut().setActive(true);

    /**
    @brief
        Constructor. Registers the PickupManager and creates the default PickupRepresentation.
    */
    PickupManager::PickupManager() : guiLoaded_(false), pickupHighestIndex_(0), defaultRepresentation_(nullptr)
    {
        RegisterObject(PickupManager);

        this->defaultRepresentation_ = new PickupRepresentation();

        orxout(internal_info, context::pickups) << "PickupManager created." << endl;
    }

    /**
    @brief
        Destructor.
        Destroys the default PickupRepresentation and does some cleanup.
    */
    PickupManager::~PickupManager()
    {
        // Destroying the default representation.
        if(this->defaultRepresentation_ != nullptr)
            this->defaultRepresentation_->destroy();

        this->representations_.clear();

        // Destroying all the PickupInventoryContainers that are still there.
        for(const auto& mapEntry : this->pickupInventoryContainers_)
            delete mapEntry.second;
        this->pickupInventoryContainers_.clear();

        // Destroying all the WeakPointers that are still there.
        this->pickups_.clear();

        this->indexes_.clear();

        orxout(internal_info, context::pickups) << "PickupManager destroyed." << endl;
    }

    /**
    @brief
        Registers a PickupRepresentation.
    @param name
        The representation's name.
    @param representation
        A pointer to the PickupRepresentation.
    @return
        Returns true if successful and false if not.
    */
    bool PickupManager::registerRepresentation(const std::string& name, PickupRepresentation* representation)
    {
        assert(representation);

        // If the list is not empty and Pickupable already has a Representation registered.
        if(!this->representations_.empty() && this->representations_.find(name) != this->representations_.end())
            return false;

        this->representations_[name] = representation;

        orxout(verbose, context::pickups) << "PickupRepresentation &" << representation << " registered with the PickupManager." << endl;
        return true;
    }

    /**
    @brief
        Unegisters a PickupRepresentation.
    @param name
        The representation's name.
    @return
        Returns true if successful and false if not.
    */
    bool PickupManager::unregisterRepresentation(const std::string& name)
    {
        std::map<std::string, PickupRepresentation*>::iterator it = this->representations_.find(name);
        if(it == this->representations_.end()) // If the Pickupable is not registered in the first place.
            return false;

        this->representations_.erase(it);

        orxout(verbose, context::pickups) << "PickupRepresentation &" << name << " unregistered with the PickupManager." << endl;
        return true;
    }

    /**
    @brief
        Get the PickupRepresentation with the given name.
    @param name
        The name of the PickupRepresentation.
    @return
        Returns a pointer to the PickupRepresentation.
    */
    PickupRepresentation* PickupManager::getRepresentation(const std::string& name)
    {
        std::map<std::string, PickupRepresentation*>::iterator it = this->representations_.find(name);
        if(it == this->representations_.end()) // If there is no PickupRepresentation associated with the input name.
        {
            orxout(verbose, context::pickups) << "PickupManager::getRepresentation() returned default representation." << endl;
            return this->defaultRepresentation_;
        }

        return it->second;
    }

    /**
    @brief
        Is called by the PickupListener to notify the PickupManager, that the input Pickupable has transited to the input used state.
    @param pickup
        The Pickupable whose used status changed.
    @param used
        The used status the Pickupable changed to.
    */
    void PickupManager::pickupChangedUsed(Pickupable* pickup, bool used)
    {
        assert(pickup);

        if(!GameMode::isMaster()) // If this is neither standalone nor the server.
            return;

        CollectiblePickup* collectible = orxonox_cast<CollectiblePickup*>(pickup);
        // If the Pickupable is part of a PickupCollection it isn't displayed in the PickupInventory, just the PickupCollection is.
        if(collectible != nullptr && collectible->isInCollection())
            return;

        // Getting clientId of the host this change of the pickup's used status concerns.
        PickupCarrier* carrier = pickup->getCarrier();
        while(carrier->getCarrierParent() != nullptr)
            carrier = carrier->getCarrierParent();
        Pawn* pawn = orxonox_cast<Pawn*>(carrier);
        if(pawn == nullptr)
            return;
        PlayerInfo* info = pawn->getPlayer();
        if(info == nullptr)
            return;
        unsigned int clientId = info->getClientID();

        // Get the number identifying the pickup.
        std::map<Pickupable*, uint32_t>::iterator it = this->indexes_.find(pickup);
        assert(it != this->indexes_.end());
        uint32_t index = it->second;

        // If we're either in standalone mode or this is the host whom the change of the pickup's status concerns.
        if(GameMode::isStandalone() || Host::getPlayerID() == clientId)
        {
            PickupManager::pickupChangedUsedNetwork(index, used, pickup->isUsable(), pickup->isUnusable());
        }
        // If the concerned host is somewhere in the network, we call pickupChangedUsedNetwork() on its PickupManager.
        else
        {
            callStaticNetworkFunction(&PickupManager::pickupChangedUsedNetwork, clientId, index, used, pickup->isUsable(), pickup->isUnusable());
        }
    }

    /**
    @brief
        Helper method to react to the change in the used status of a Pickupable.
        Static method that is used by the server to inform the client it concerns about the status change.
        The parameters that are given are used to update the information (i.e. the PickupInventoryContainer) the concerning PickupManager has about the Pickupable that changed.
    @param pickup
        A number identifying the Pickupable that changed its used status.
    @param inUse
        The used status the Pickupable changed to. (i.e. whether the Pickupable is in use or not).
    @param usable
        Whether the Pickupable's used status can be changed used in the PickupInventory.
    @param unusable
        Whether the Pickupable's used status can be changed to unused in the PickupInventory.
    */
    /*static*/ void PickupManager::pickupChangedUsedNetwork(uint32_t pickup, bool inUse, bool usable, bool unusable)
    {
        PickupManager& manager = PickupManager::getInstance(); // Get the PickupManager singleton on this host.
        // If the input Pickupable (i.e its identifier) is not present in the list the PickupManager has.
        if(manager.pickupInventoryContainers_.find(pickup) == manager.pickupInventoryContainers_.end())
        {
            orxout(internal_error, context::pickups) << "Pickupable &(" << pickup << ") was not registered with PickupManager for the PickupInventory, when it changed used." << endl;
            return;
        }

        // Update the Pickupable's container with the information transferred.
        manager.pickupInventoryContainers_[pickup]->inUse = inUse;
        manager.pickupInventoryContainers_[pickup]->usable = usable;
        manager.pickupInventoryContainers_[pickup]->unusable = unusable;

        manager.updateGUI(); // Tell the PickupInventory that something has changed.
    }

    /**
    @brief
        Is called by the PickupListener to notify the PickupManager, that the input Pickupable has transited to the input pickedUp state.
    @param pickup
        The Pickupable whose pickedUp status changed.
    @param pickedUp
        The pickedUp status the Pickupable changed to.
    */
    void PickupManager::pickupChangedPickedUp(Pickupable* pickup, bool pickedUp)
    {
        assert(pickup);


        for (HUDPickupSystem* hud : ObjectList<HUDPickupSystem>())
            pickupSystem = hud;
        
        assert(pickupSystem); //pickupSystem HAS to be there!

        if(!GameMode::isMaster()) // If this is neither standalone nor the server.
            return;

        CollectiblePickup* collectible = orxonox_cast<CollectiblePickup*>(pickup);
        // If the Pickupable is part of a PickupCollection it isn't displayed in the PickupInventory, just the PickupCollection is.
        if(collectible != nullptr && collectible->isInCollection())
            return;

        // Getting clientId of the host this change of the pickup's pickedUp status concerns.
        PickupCarrier* carrier = pickup->getCarrier();
        while(carrier->getCarrierParent() != nullptr)
            carrier = carrier->getCarrierParent();
        Pawn* pawn = orxonox_cast<Pawn*>(carrier);
        if(pawn == nullptr)
            return;
        PlayerInfo* info = pawn->getFormerPlayer();
        if(info == nullptr)
            return;
        unsigned int clientId = info->getClientID();

        uint32_t index = 0;
        if(pickedUp) // If the Pickupable has changed to picked up, it is added to the required lists.
        {
            index = this->getPickupIndex(); // Get a new identifier (index) for the Pickupable.
            // Add the Pickupable to the indexes_ and pickups_ lists.
            this->indexes_[pickup] = index;
            this->pickups_[index] = pickup;

            orxout() << "the pickup is: " << pickup << endl;

            this->picks.push_back(pickup);

            pickupSystem->updatePickupList(picks);
            
        }
        else // If it was dropped, it is removed from the required lists.
        {
            // Get the indentifier (index) that identifies the input Pickupable.
            std::map<Pickupable*, uint32_t>::iterator it = this->indexes_.find(pickup);
            index = it->second;

            this->indexes_.erase(pickup);
            this->pickups_.erase(index); //set to null, so that can be identified as free slot by getPickupIndex()


            this->picks.erase(std::remove(this->picks.begin(), this->picks.end(), pickup), this->picks.end()); //remove pickup from vector

            pickupSystem->removePickup(pickup);
        }

        // If we're either in standalone mode or this is the host whom the change of the pickup's status concerns.
        if(GameMode::isStandalone() || Host::getPlayerID() == clientId)
        {
            // If there is no PickupRepresentation registered the default representation is used.
            if(this->representations_.find(pickup->getRepresentationName()) == this->representations_.end())
                PickupManager::pickupChangedPickedUpNetwork(index, pickup->isUsable(), this->defaultRepresentation_->getObjectID(), pickup->getRepresentationName(), pickedUp);
            else
                PickupManager::pickupChangedPickedUpNetwork(index, pickup->isUsable(), this->representations_[pickup->getRepresentationName()]->getObjectID(), pickup->getRepresentationName(), pickedUp);
        }
        // If the concerned host is somewhere in the network, we call pickupChangedPickedUpNetwork() on its PickupManager.
        else
        {
            // If there is no PickupRepresentation registered the default representation is used.
            if(this->representations_.find(pickup->getRepresentationName()) == this->representations_.end())
            {
                callStaticNetworkFunction(&PickupManager::pickupChangedPickedUpNetwork, clientId, index, pickup->isUsable(), this->defaultRepresentation_->getObjectID(), pickedUp);
            }
            else
            {
                callStaticNetworkFunction(&PickupManager::pickupChangedPickedUpNetwork, clientId, index, pickup->isUsable(), this->representations_[pickup->getRepresentationName()]->getObjectID(), pickedUp);
            }
        }

    }

    //This function is called by the command line or by the key binding
    //it uses or unuses the pickup, depending on its current state
    void PickupManager::useUnusePickup(uint32_t index) 
    {
        orxout() << "Hello there I was here " << index << endl;

        PickupManager& manager = PickupManager::getInstance();

        if(!manager.pickups_.count(index)) return; //if pickup is no longer here, dont do anything

        Pickupable* pickup=manager.pickups_.find(index)->second;
        if(pickup==nullptr)
        {
            orxout() << "The pickup does not exist." << endl;
            return;                       //pickup does not exist
        }

        orxout() << "The pickup is being used: " << pickup->isUsed() << endl;

        manager.dropPickup(index);

        // if(pickup->isUsed())
        //     manager.usePickup(index, false);
        // else
        //     manager.usePickup(index, true);
    }


    /**
    @brief
        Helper method to react to the change in the pickedUp status of a Pickupable.
        Static method that is used by the server to inform the client it concerns about the status change.
        The parameters that are given are used to update the information (i.e. the PickupInventoryContainer) the concerning PickupManager has about the Pickupable that changed.
    @param pickup
        A number identifying the Pickupable that changed its pickedUp status.
    @param usable
        Whether the Pickupable's used status can be changed to used in the PickupInventory.
    @param representationObjectId
        The objectId identifying (over the network) the PickupRepresentation that represents this Pickupable.
    @param representationName
        The name of the associated PickupRepresentation
    @param pickedUp
        The pickedUp status the Pickupable changed to.
    */
    /*static*/ void PickupManager::pickupChangedPickedUpNetwork(uint32_t pickup, bool usable, uint32_t representationObjectId, const std::string& representationName, bool pickedUp)
    {
        PickupManager& manager = PickupManager::getInstance(); // Get the PickupManager singleton on this host.
        // If the Pickupable has been picked up, we create a new PickupInventoryContainer for it.
        if(pickedUp)
        {
            // Create a new PickupInventoryContainer for the Pickupable and set all the necessary information.
            PickupInventoryContainer* container = new PickupInventoryContainer;
            container->pickup = pickup;
            container->inUse = false;
            container->pickedUp = pickedUp;
            container->usable = usable;
            container->unusable = false;
            container->representationObjectId = representationObjectId;
            container->representationName = representationName;
            // Insert the container into the pickupInventoryContainers_ list.
            manager.pickupInventoryContainers_.insert(std::pair<uint32_t, PickupInventoryContainer*>(pickup, container));

            manager.updateGUI(); // Tell the PickupInventory that something has changed.
        }
        // If the Pickupable has been dropped, we remove it from the pickupInventoryContainers_ list.
        else
        {
            std::map<uint32_t, PickupInventoryContainer*>::iterator it = manager.pickupInventoryContainers_.find(pickup);
            if(it != manager.pickupInventoryContainers_.end())
                delete it->second;
            manager.pickupInventoryContainers_.erase(pickup);

            manager.updateGUI(); // Tell the PickupInventory that something has changed.
        }
    }

    /**
    @brief
        Get the number of pickups currently picked up by the player.
        This method is used in lua to populate the PickupInventory. The intended usage is to call this method to reset the iterator of the list of PickupInventoryContainers and then use popPickup() to get the individual PickupInventoryContainers.
    @return
        Returns the number of the players picked up Pickupables.
    */
    int PickupManager::getNumPickups(void)
    {
        this->pickupsIterator_ = this->pickupInventoryContainers_.begin(); // Reset iterator.

        return this->pickupInventoryContainers_.size();
    }

    /**
    @brief
        Drop the input Pickupable.
        This method checks whether the input Pickupable still exists and drops it, if so.
    @param pickup
        The identifier of the Pickupable to be dropped.
    */
    void PickupManager::dropPickup(uint32_t pickup)
    {
        // If we're either server or standalone and the list of pickups is not empty, we find and drop the input pickup.
        if(GameMode::isMaster())
        {
            if(this->pickups_.empty())
                return;
            Pickupable* pickupable = this->pickups_.find(pickup)->second;
            if(pickupable != nullptr)
            {
                pickupable->drop();

            }
        }
        // If we're neither server nor standalone we drop the pickup by calling dropPickupNetworked() of the PickupManager on the server.
        else
        {
            callStaticNetworkFunction(&PickupManager::dropPickupNetworked, 0, pickup);
        }
    }

    /**
    @brief
        Helper method to drop the input pickup on the server.
        Static method that is used by clients to instruct the server to drop the input pickup.
    @param pickup
        The identifier of the Pickupable to be dropped.
    */
    /*static*/ void PickupManager::dropPickupNetworked(uint32_t pickup)
    {
        if(GameMode::isServer()) // Obviously we only want to do this on the server.
        {
            PickupManager& manager = PickupManager::getInstance();
            manager.dropPickup(pickup);
        }
    }

    /**
    @brief
        Use (or unuse) the input Pickupable.
        This method checks whether the input Pickupable still exists and uses (or unuses) it, if so,
    @param pickup
        The identifier of the Pickupable to be used (or unused).
    @param use
        If true the input Pickupable is used, if false it is unused.
    */
    void PickupManager::usePickup(uint32_t pickup, bool use)
    {
        // If we're either server or standalone and the list of pickups is not empty, we find and change the used status of the input pickup.
        if(GameMode::isMaster())
        {
            if(this->pickups_.empty())
                return;
            Pickupable* pickupable = this->pickups_.find(pickup)->second;
            if(pickupable != nullptr)
                pickupable->setUsed(use);
        }
        // If we're neither server nor standalone we change the used status of the pickup by calling usePickupNetworked() of the PickupManager on the server.
        else
        {
            callStaticNetworkFunction(&PickupManager::usePickupNetworked, 0, pickup, use);
        }
    }

    /**
    @brief
        Helper method to use (or unuse) the input Pickupable on the server.
        Static method that is used by clients to instruct the server to use (or unuse) the input pickup.
    @param pickup
        The identifier of the Pickupable to be used (or unused).
    @param use
        If true the input Pickupable is used, if false it is unused.
    */
    /*static*/ void PickupManager::usePickupNetworked(uint32_t pickup, bool use)
    {
        if(GameMode::isServer())
        {
            PickupManager& manager = PickupManager::getInstance();
            manager.usePickup(pickup, use);
        }
    }

    /**
    @brief
        Updates the PickupInventory GUI.
        Also loads the PickupInventory GUI if is hasn't been done already.
    */
    inline void PickupManager::updateGUI(void)
    {
        // We only need to update (and load) the GUI if this host shows graphics.
        if(GameMode::showsGraphics())
        {
            if(!this->guiLoaded_) // If the GUI hasn't been loaded, yet, we load it.
            {
                GUIManager::getInstance().loadGUI(PickupManager::guiName_s);
                this->guiLoaded_ = true;
            }

            // Update the GUI.
            GUIManager::getInstance().getLuaState()->doString(PickupManager::guiName_s + ".update()");
        }
    }

    /**
    @brief
        Get a new index between 0 and 9 for a Pickupable.
        If all slots are occupied, the Pickupable in the first slot will be dropped.
    @return
        Returns the new index.
    */
    uint32_t PickupManager::getPickupIndex(void)
    {
        //check if there are free slots available

        for(uint32_t i=0; i<10; i++)
        {
            if(!pickups_.count(i)) return i;
        }
        //all slots are full and we have to drop sth
        orxout() << "everything was full and we have now dropped the first element" << endl;
        this->dropPickup(0);
        return 0;
    }

}