/*
 * Copyright (C) 2016+ AzerothCore <www.azerothcore.org>, released under GNU GPL v2 license, you may redistribute it and/or modify it under version 2 of the License, or (at your option), any later version.
 */

#include "LootObjectStack.h"
#include "LootMgr.h"
#include "Playerbots.h"

#define MAX_LOOT_OBJECT_COUNT 10

LootTarget::LootTarget(ObjectGuid guid) : guid(guid), asOfTime(time(nullptr))
{
}

LootTarget::LootTarget(LootTarget const& other)
{
    guid = other.guid;
    asOfTime = other.asOfTime;
}

LootTarget& LootTarget::operator=(LootTarget const& other)
{
    if ((void*)this == (void*)&other)
        return *this;

    guid = other.guid;
    asOfTime = other.asOfTime;

    return *this;
}

bool LootTarget::operator<(LootTarget const& other) const
{
    return guid < other.guid;
}

void LootTargetList::shrink(time_t fromTime)
{
    for (std::set<LootTarget>::iterator i = begin(); i != end(); )
    {
        if (i->asOfTime <= fromTime)
            erase(i++);
		else
			++i;
    }
}

LootObject::LootObject(Player* bot, ObjectGuid guid) : guid(), skillId(SKILL_NONE), reqSkillValue(0), reqItem(0)
{
    Refresh(bot, guid);
}

void LootObject::Refresh(Player* bot, ObjectGuid lootGUID)
{
    skillId = SKILL_NONE;
    reqSkillValue = 0;
    reqItem = 0;
    guid.Clear();

    PlayerbotAI* botAI = GET_PLAYERBOT_AI(bot);
    Creature* creature = botAI->GetCreature(lootGUID);
    if (creature && creature->getDeathState() == CORPSE)
    {
        if (creature->HasFlag(UNIT_DYNAMIC_FLAGS, UNIT_DYNFLAG_LOOTABLE))
            guid = lootGUID;

        if (creature->HasFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_SKINNABLE))
        {
            skillId = creature->GetCreatureTemplate()->GetRequiredLootSkill();
            uint32 targetLevel = creature->getLevel();
            reqSkillValue = targetLevel < 10 ? 1 : targetLevel < 20 ? (targetLevel - 10) * 10 : targetLevel * 5;
            if (botAI->HasSkill((SkillType) skillId) && bot->GetSkillValue(skillId) >= reqSkillValue)
                guid = lootGUID;
        }

        return;
    }

    GameObject* go = botAI->GetGameObject(lootGUID);
    if (go && go->isSpawned() && go->GetGoState() == GO_STATE_READY)
    {
        uint32 lockId = go->GetGOInfo()->GetLockId();
        LockEntry const* lockInfo = sLockStore.LookupEntry(lockId);
        if (!lockInfo)
            return;

        for (uint8 i = 0; i < 8; ++i)
        {
            switch (lockInfo->Type[i])
            {
                case LOCK_KEY_ITEM:
                    if (lockInfo->Index[i] > 0)
                    {
                        reqItem = lockInfo->Index[i];
                        guid = lootGUID;
                    }
                    break;
                case LOCK_KEY_SKILL:
                    if (SkillByLockType(LockType(lockInfo->Index[i])) > 0)
                    {
                        skillId = SkillByLockType(LockType(lockInfo->Index[i]));
                        reqSkillValue = std::max((uint32)1, lockInfo->Skill[i]);
                        guid = lootGUID;
                    }
                    break;
                case LOCK_KEY_NONE:
                    guid = lootGUID;
                    break;
                }
        }
    }
}

WorldObject* LootObject::GetWorldObject(Player* bot)
{
    Refresh(bot, guid);

    PlayerbotAI* botAI = GET_PLAYERBOT_AI(bot);

    Creature* creature = botAI->GetCreature(guid);
    if (creature && creature->getDeathState() == CORPSE)
        return creature;

    GameObject* go = botAI->GetGameObject(guid);
    if (go && go->isSpawned())
        return go;

    return nullptr;
}

LootObject::LootObject(LootObject const& other)
{
    guid = other.guid;
    skillId = other.skillId;
    reqSkillValue = other.reqSkillValue;
    reqItem = other.reqItem;
}

bool LootObject::IsLootPossible(Player* bot)
{
    if (IsEmpty() || !GetWorldObject(bot))
        return false;

    PlayerbotAI* botAI = GET_PLAYERBOT_AI(bot);

    if (reqItem && !bot->HasItemCount(reqItem, 1))
        return false;

    if (abs(GetWorldObject(bot)->GetPositionZ() - bot->GetPositionZ()) > INTERACTION_DISTANCE)
        return false;

    Creature* creature = botAI->GetCreature(guid);
    if (creature && creature->getDeathState() == CORPSE)
    {
        if (!creature->loot.hasItemFor(bot) && skillId != SKILL_SKINNING)
            return false;
    }

    if (skillId == SKILL_NONE)
        return true;

    if (skillId == SKILL_FISHING)
        return false;

    if (!botAI->HasSkill((SkillType)skillId))
        return false;

    if (!reqSkillValue)
        return true;

    uint32 skillValue = uint32(bot->GetSkillValue(skillId));
    if (reqSkillValue > skillValue)
        return false;

    if (skillId == SKILL_MINING && !bot->HasItemCount(2901, 1))
        return false;

    if (skillId == SKILL_SKINNING && !bot->HasItemCount(7005, 1))
        return false;

    return true;
}

bool LootObjectStack::Add(ObjectGuid guid)
{
    if (!availableLoot.insert(guid).second)
        return false;

    if (availableLoot.size() < MAX_LOOT_OBJECT_COUNT)
        return true;

    std::vector<LootObject> ordered = OrderByDistance();
    for (size_t i = MAX_LOOT_OBJECT_COUNT; i < ordered.size(); i++)
        Remove(ordered[i].guid);

    return true;
}

void LootObjectStack::Remove(ObjectGuid guid)
{
    LootTargetList::iterator i = availableLoot.find(guid);
    if (i != availableLoot.end())
        availableLoot.erase(i);
}

void LootObjectStack::Clear()
{
    availableLoot.clear();
}

bool LootObjectStack::CanLoot(float maxDistance)
{
    std::vector<LootObject> ordered = OrderByDistance(maxDistance);
    return !ordered.empty();
}

LootObject LootObjectStack::GetLoot(float maxDistance)
{
    std::vector<LootObject> ordered = OrderByDistance(maxDistance);
    return ordered.empty() ? LootObject() : *ordered.begin();
}

std::vector<LootObject> LootObjectStack::OrderByDistance(float maxDistance)
{
    availableLoot.shrink(time(nullptr) - 30);

    std::map<float, LootObject> sortedMap;
    LootTargetList safeCopy(availableLoot);
    for (LootTargetList::iterator i = safeCopy.begin(); i != safeCopy.end(); i++)
    {
        ObjectGuid guid = i->guid;
        LootObject lootObject(bot, guid);
        if (!lootObject.IsLootPossible(bot))
            continue;

        float distance = bot->GetDistance(lootObject.GetWorldObject(bot));
        if (!maxDistance || distance <= maxDistance)
            sortedMap[distance] = lootObject;
    }

    std::vector<LootObject> result;
    for (std::map<float, LootObject>::iterator i = sortedMap.begin(); i != sortedMap.end(); i++)
        result.push_back(i->second);

    return result;
}