#include "actionequip.hpp"

#include "../mwbase/environment.hpp"
#include "../mwbase/world.hpp"
#include "../mwbase/windowmanager.hpp"

#include "../mwmechanics/actorutil.hpp"

#include <components/compiler/locals.hpp>

#include "inventorystore.hpp"
#include "player.hpp"
#include "class.hpp"

namespace MWWorld
{
    ActionEquip::ActionEquip (const MWWorld::Ptr& object, bool force)
    : Action (false, object)
    , mForce(force)
    {
    }

    void ActionEquip::executeImp (const Ptr& actor)
    {
        MWWorld::Ptr object = getTarget();
        MWWorld::InventoryStore& invStore = actor.getClass().getInventoryStore(actor);

        if (object.getClass().hasItemHealth(object) && object.getCellRef().getCharge() == 0)
        {
            if (actor == MWMechanics::getPlayer())
                MWBase::Environment::get().getWindowManager()->messageBox("#{sInventoryMessage1}");

            return;
        }

        if (!mForce)
        {
            std::pair <int, std::string> result = object.getClass().canBeEquipped (object, actor);

            // display error message if the player tried to equip something
            if (!result.second.empty() && actor == MWMechanics::getPlayer())
                MWBase::Environment::get().getWindowManager()->messageBox(result.second);

            switch(result.first)
            {
                case 0:
                    return;
                default:
                    break;
            }
        }

        // slots that this item can be equipped in
        std::pair<std::vector<int>, bool> slots_ = getTarget().getClass().getEquipmentSlots(getTarget());
        if (slots_.first.empty())
            return;

        // retrieve ContainerStoreIterator to the item
        MWWorld::ContainerStoreIterator it = invStore.begin();
        for (; it != invStore.end(); ++it)
        {
            if (*it == object)
            {
                break;
            }
        }

        if (it == invStore.end())
        {
            std::stringstream error;
            error << "ActionEquip can't find item " << object.getCellRef().getRefId();
            throw std::runtime_error(error.str());
        }

        // equip the item in the first free slot
        std::vector<int>::const_iterator slot=slots_.first.begin();
        for (;slot!=slots_.first.end(); ++slot)
        {
            // if the item is equipped already, nothing to do
            if (invStore.getSlot(*slot) == it)
                return;

            if (invStore.getSlot(*slot) == invStore.end())
            {
                // slot is not occupied
                invStore.equip(*slot, it, actor);
                break;
            }
        }

        // all slots are occupied -> cycle
        // move all slots one towards begin(), then equip the item in the slot that is now free
        if (slot == slots_.first.end())
        {
            for (slot=slots_.first.begin();slot!=slots_.first.end(); ++slot)
            {
                invStore.unequipSlot(*slot, actor);
                if (slot+1 != slots_.first.end())
                    invStore.equip(*slot, invStore.getSlot(*(slot+1)), actor);
                else
                    invStore.equip(*slot, it, actor);
            }
        }
    }
}