#include "servers/CNShardServer.hpp"
#include "Missions.hpp"
#include "PlayerManager.hpp"
#include "Nanos.hpp"
#include "Items.hpp"

#include "string.h"

using namespace Missions;

std::map<int32_t, Reward*> Missions::Rewards;
std::map<int32_t, TaskData*> Missions::Tasks;
nlohmann::json Missions::AvatarGrowth[37];

static void saveMission(Player* player, int missionId) {
    // sanity check missionID so we don't get exceptions
    if (missionId < 0 || missionId > 1023) {
        std::cout << "[WARN] Client submitted invalid missionId: " <<missionId<< std::endl;
        return;
    }

    // Missions are stored in int64_t array
    int row = missionId / 64;
    int column = missionId % 64;
    player->aQuestFlag[row] |= (1ULL << column);
}

static int findQSlot(Player *plr, int id) {
    int i;

    // two passes. we mustn't fail to find an existing stack.
    for (i = 0; i < AQINVEN_COUNT; i++)
        if (plr->QInven[i].iID == id)
            return i;

    // no stack. start a new one.
    for (i = 0; i < AQINVEN_COUNT; i++)
        if (plr->QInven[i].iOpt == 0)
            return i;

    // not found
    return -1;
}

static bool isQuestItemFull(CNSocket* sock, int itemId, int itemCount) {
    Player* plr = PlayerManager::getPlayer(sock);

    int slot = findQSlot(plr, itemId);
    if (slot == -1) {
        // this should never happen
        std::cout << "[WARN] Player has no room for quest item!?" << std::endl;
        return true;
    }

    return (itemCount == plr->QInven[slot].iOpt);
}

static void dropQuestItem(CNSocket *sock, int task, int count, int id, int mobid) {
    std::cout << "Altered item id " << id << " by " << count << " for task id " << task << std::endl;
    const size_t resplen = sizeof(sP_FE2CL_REP_REWARD_ITEM) + sizeof(sItemReward);
    assert(resplen < CN_PACKET_BUFFER_SIZE);
    // we know it's only one trailing struct, so we can skip full validation

    Player *plr = PlayerManager::getPlayer(sock);

    uint8_t respbuf[resplen]; // not a variable length array, don't worry
    sP_FE2CL_REP_REWARD_ITEM *reward = (sP_FE2CL_REP_REWARD_ITEM *)respbuf;
    sItemReward *item = (sItemReward *)(respbuf + sizeof(sP_FE2CL_REP_REWARD_ITEM));

    // don't forget to zero the buffer!
    memset(respbuf, 0, resplen);

    // find free quest item slot
    int slot = findQSlot(plr, id);
    if (slot == -1) {
        // this should never happen
        std::cout << "[WARN] Player has no room for quest item!?" << std::endl;
        return;
    }
    if (id != 0)
        std::cout << "new qitem in slot " << slot << std::endl;

    // update player
    if (id != 0) {
        plr->QInven[slot].iType = 8;
        plr->QInven[slot].iID = id;
        plr->QInven[slot].iOpt += count; // stacking
    }

    // fully destory deleted items, for good measure
    if (plr->QInven[slot].iOpt <= 0)
        memset(&plr->QInven[slot], 0, sizeof(sItemBase));

    // preserve stats
    reward->m_iCandy = plr->money;
    reward->m_iFusionMatter = plr->fusionmatter;
    reward->iFatigue = 100; // prevents warning message
    reward->iFatigue_Level = 1;
    reward->m_iBatteryN = plr->batteryN;
    reward->m_iBatteryW = plr->batteryW;

    reward->iItemCnt = 1; // remember to update resplen if you change this
    reward->iTaskID = task;
    reward->iNPC_TypeID = mobid;

    item->sItem = plr->QInven[slot];
    item->iSlotNum = slot;
    item->eIL = 2;

    sock->sendPacket((void*)respbuf, P_FE2CL_REP_REWARD_ITEM, resplen);
}

static int giveMissionReward(CNSocket *sock, int task, int choice=0) {
    Reward *reward = Rewards[task];
    Player *plr = PlayerManager::getPlayer(sock);

    int nrewards = 0;
    for (int i = 0; i < 4; i++) {
        if (reward->itemIds[i] != 0)
            nrewards++;
    }

    // this handles multiple choice rewards in the Academy's Mt. Neverest missions
    if (choice != 0)
        nrewards = 1;

    int slots[4];
    for (int i = 0; i < nrewards; i++) {
        slots[i] = Items::findFreeSlot(plr);
        if (slots[i] == -1) {
            std::cout << "Not enough room to complete task" << std::endl;
            INITSTRUCT(sP_FE2CL_REP_PC_TASK_END_FAIL, fail);

            fail.iTaskNum = task;
            fail.iErrorCode = 13; // inventory full

            sock->sendPacket((void*)&fail, P_FE2CL_REP_PC_TASK_END_FAIL, sizeof(sP_FE2CL_REP_PC_TASK_END_FAIL));

            // delete any temp items we might have set
            for (int j = 0; j < i; j++) {
                plr->Inven[slots[j]] = { 0, 0, 0, 0 }; // empty
            }
            return -1;
        }
        
        plr->Inven[slots[i]] = { 999, 999, 999, 0 }; // temp item; overwritten later
    }

    uint8_t respbuf[CN_PACKET_BUFFER_SIZE];
    size_t resplen = sizeof(sP_FE2CL_REP_REWARD_ITEM) + nrewards * sizeof(sItemReward);
    assert(resplen < CN_PACKET_BUFFER_SIZE);
    sP_FE2CL_REP_REWARD_ITEM *resp = (sP_FE2CL_REP_REWARD_ITEM *)respbuf;
    sItemReward *item = (sItemReward *)(respbuf + sizeof(sP_FE2CL_REP_REWARD_ITEM));

    // don't forget to zero the buffer!
    memset(respbuf, 0, resplen);

    // update player
    plr->money += reward->money;
    if (plr->iConditionBitFlag & CSB_BIT_REWARD_CASH) { // nano boost for taros
        int boost = 0;
        if (Nanos::getNanoBoost(plr)) // for gumballs
            boost = 1;
        plr->money += reward->money * (5 + boost) / 25;
    }

    if (plr->iConditionBitFlag & CSB_BIT_REWARD_BLOB) { // nano boost for fm
        int boost = 0;
        if (Nanos::getNanoBoost(plr)) // for gumballs
            boost = 1;
        updateFusionMatter(sock, reward->fusionmatter * (30 + boost) / 25);
    } else
        updateFusionMatter(sock, reward->fusionmatter);

    // simple rewards
    resp->m_iCandy = plr->money;
    resp->m_iFusionMatter = plr->fusionmatter;
    resp->iFatigue = 100; // prevents warning message
    resp->iFatigue_Level = 1;
    resp->iItemCnt = nrewards;
    resp->m_iBatteryN = plr->batteryN;
    resp->m_iBatteryW = plr->batteryW;

    int offset = 0;

    // choice is actually a bitfield
    if (choice != 0)
        offset = (int)log2((int)choice);

    for (int i = 0; i < nrewards; i++) {
        item[i].sItem.iType = reward->itemTypes[offset+i];
        item[i].sItem.iID = reward->itemIds[offset+i];
        item[i].sItem.iOpt = 1;
        item[i].iSlotNum = slots[i];
        item[i].eIL = 1;

        // update player inventory, overwriting temporary item
        plr->Inven[slots[i]] = item[i].sItem;
    }

    sock->sendPacket((void*)respbuf, P_FE2CL_REP_REWARD_ITEM, resplen);

    return 0;
}

static bool endTask(CNSocket *sock, int32_t taskNum, int choice=0) {
    Player *plr = PlayerManager::getPlayer(sock);

    if (Tasks.find(taskNum) == Tasks.end())
        return false;

    // ugly pointer/reference juggling for the sake of operator overloading...
    TaskData& task = *Tasks[taskNum];

    // update player
    int i;
    for (i = 0; i < ACTIVE_MISSION_COUNT; i++) {
        if (plr->tasks[i] == taskNum) {
            plr->tasks[i] = 0;
            for (int j = 0; j < 3; j++) {
                plr->RemainingNPCCount[i][j] = 0;
            }
        }
    }
    if (i == ACTIVE_MISSION_COUNT - 1 && plr->tasks[i] != 0) {
        std::cout << "[WARN] Player completed non-active mission!?" << std::endl;
        return false;
    }

    // mission rewards
    if (Rewards.find(taskNum) != Rewards.end()) {
        if (giveMissionReward(sock, taskNum, choice) == -1)
            return false; // we don't want to send anything
    }
    // don't take away quest items if we haven't finished the quest

    /*
     * Give (or take away) quest items
     *
     * Some mission tasks give the player a quest item upon completion.
     * This is distinct from quest item mob drops.
     * They can be identified by a counter in the task indicator (ie. 1/1 Gravity Decelerator).
     * The server is responsible for dropping the correct item.
     * Yes, this is pretty stupid.
     *
     * iSUInstancename is the number of items to give. It is usually negative at the end of
     * a mission, to clean up its quest items.
     */

    for (int i = 0; i < 3; i++)
        if (task["m_iSUItem"][i] != 0)
            dropQuestItem(sock, taskNum, task["m_iSUInstancename"][i], task["m_iSUItem"][i], 0);

    // if it's the last task
    if (task["m_iSUOutgoingTask"] == 0) {
        // save completed mission on player
        saveMission(plr, (int)(task["m_iHMissionID"])-1);

        // if it's a nano mission, reward the nano.
        if (task["m_iSTNanoID"] != 0)
            Nanos::addNano(sock, task["m_iSTNanoID"], 0, true);

        // remove current mission
        plr->CurrentMissionID = 0;
    }

    return true;
}

bool Missions::startTask(Player* plr, int TaskID) {
    if (Missions::Tasks.find(TaskID) == Missions::Tasks.end()) {
        std::cout << "[WARN] Player submitted unknown task!?" << std::endl;
        return false;
    }

    TaskData& task = *Missions::Tasks[TaskID];

    // client freaks out if nano mission isn't sent first after relogging, so it's easiest to set it here
    if (task["m_iSTNanoID"] != 0 && plr->tasks[0] != 0) {
            // lets move task0 to different spot
            int moveToSlot = 1;
            for (; moveToSlot < ACTIVE_MISSION_COUNT; moveToSlot++)
                if (plr->tasks[moveToSlot] == 0)
                    break;

            plr->tasks[moveToSlot] = plr->tasks[0];
            plr->tasks[0] = 0;
            for (int i = 0; i < 3; i++) {
                plr->RemainingNPCCount[moveToSlot][i] = plr->RemainingNPCCount[0][i];
                plr->RemainingNPCCount[0][i] = 0;
            }
    }

    int i;
    for (i = 0; i < ACTIVE_MISSION_COUNT; i++) {
        if (plr->tasks[i] == 0) {
            plr->tasks[i] = TaskID;
            for (int j = 0; j < 3; j++) {
                plr->RemainingNPCCount[i][j] = (int)task["m_iCSUNumToKill"][j];
            }
            break;
        }
    }

    if (i == ACTIVE_MISSION_COUNT - 1 && plr->tasks[i] != TaskID) {
        std::cout << "[WARN] Player has more than 6 active missions!?" << std::endl;
        return false;
    }

    return true;
}

static void taskStart(CNSocket* sock, CNPacketData* data) {
    sP_CL2FE_REQ_PC_TASK_START* missionData = (sP_CL2FE_REQ_PC_TASK_START*)data->buf;
    INITSTRUCT(sP_FE2CL_REP_PC_TASK_START_SUCC, response);
    Player *plr = PlayerManager::getPlayer(sock);

    if (!startTask(plr, missionData->iTaskNum)) {
        // TODO: TASK_FAIL?
        response.iTaskNum = missionData->iTaskNum;
        sock->sendPacket((void*)&response, P_FE2CL_REP_PC_TASK_START_SUCC, sizeof(sP_FE2CL_REP_PC_TASK_START_SUCC));
        return;
    }

    TaskData& task = *Tasks[missionData->iTaskNum];

    // Give player their delivery items at the start, or reset them to 0 at the start.
    for (int i = 0; i < 3; i++)
        if (task["m_iSTItemID"][i] != 0)
            dropQuestItem(sock, missionData->iTaskNum, task["m_iSTItemNumNeeded"][i], task["m_iSTItemID"][i], 0);
    std::cout << "Mission requested task: " << missionData->iTaskNum << std::endl;
    response.iTaskNum = missionData->iTaskNum;
    response.iRemainTime = task["m_iSTGrantTimer"];
    sock->sendPacket((void*)&response, P_FE2CL_REP_PC_TASK_START_SUCC, sizeof(sP_FE2CL_REP_PC_TASK_START_SUCC));

    // HACK: auto-succeed escort task
    if (task["m_iHTaskType"] == 6) {
        std::cout << "Skipping escort mission" << std::endl;
        INITSTRUCT(sP_FE2CL_REP_PC_TASK_END_SUCC, response);

        endTask(sock, missionData->iTaskNum);
        response.iTaskNum = missionData->iTaskNum;

        sock->sendPacket((void*)&response, P_FE2CL_REP_PC_TASK_END_SUCC, sizeof(sP_FE2CL_REP_PC_TASK_END_SUCC));
    }
}

static void taskEnd(CNSocket* sock, CNPacketData* data) {
    sP_CL2FE_REQ_PC_TASK_END* missionData = (sP_CL2FE_REQ_PC_TASK_END*)data->buf;

    // failed timed missions give an iNPC_ID of 0
    if (missionData->iNPC_ID == 0) {
        TaskData* task = Missions::Tasks[missionData->iTaskNum];
        if (task->task["m_iSTGrantTimer"] > 0) { // its a timed mission
            Player* plr = PlayerManager::getPlayer(sock);
            /*
             * Enemy killing missions
             * this is gross and should be cleaned up later
             * once we comb over mission logic more throughly
             */
            bool mobsAreKilled = false;
            if (task->task["m_iHTaskType"] == 5) {
                mobsAreKilled = true;
                for (int i = 0; i < ACTIVE_MISSION_COUNT; i++) {
                    if (plr->tasks[i] == missionData->iTaskNum) {
                        for (int j = 0; j < 3; j++) {
                            if (plr->RemainingNPCCount[i][j] > 0) {
                                mobsAreKilled = false;
                                break;
                            }
                        }
                    }
                }
            }

            if (!mobsAreKilled) {
                
                int failTaskID = task->task["m_iFOutgoingTask"];
                if (failTaskID != 0) {
                    Missions::quitTask(sock, missionData->iTaskNum, false);
                    
                    for (int i = 0; i < 6; i++)
                        if (plr->tasks[i] == missionData->iTaskNum)
                            plr->tasks[i] = failTaskID;
                    return;
                }
            }
        }
    }

    INITSTRUCT(sP_FE2CL_REP_PC_TASK_END_SUCC, response);

    response.iTaskNum = missionData->iTaskNum;

    if (!endTask(sock, missionData->iTaskNum, missionData->iBox1Choice)) {
        return;
    }

    sock->sendPacket((void*)&response, P_FE2CL_REP_PC_TASK_END_SUCC, sizeof(sP_FE2CL_REP_PC_TASK_END_SUCC));
}

static void setMission(CNSocket* sock, CNPacketData* data) {
    Player* plr = PlayerManager::getPlayer(sock);

    sP_CL2FE_REQ_PC_SET_CURRENT_MISSION_ID* missionData = (sP_CL2FE_REQ_PC_SET_CURRENT_MISSION_ID*)data->buf;
    INITSTRUCT(sP_FE2CL_REP_PC_SET_CURRENT_MISSION_ID, response);
    response.iCurrentMissionID = missionData->iCurrentMissionID;
    plr->CurrentMissionID = missionData->iCurrentMissionID;

    sock->sendPacket((void*)&response, P_FE2CL_REP_PC_SET_CURRENT_MISSION_ID, sizeof(sP_FE2CL_REP_PC_SET_CURRENT_MISSION_ID));
}

static void quitMission(CNSocket* sock, CNPacketData* data) {
    sP_CL2FE_REQ_PC_TASK_STOP* missionData = (sP_CL2FE_REQ_PC_TASK_STOP*)data->buf;
    quitTask(sock, missionData->iTaskNum, true);
}

void Missions::quitTask(CNSocket* sock, int32_t taskNum, bool manual) {
    Player* plr = PlayerManager::getPlayer(sock);

    if (Tasks.find(taskNum) == Tasks.end())
        return; // sanity check

    // update player
    int i;
    for (i = 0; i < ACTIVE_MISSION_COUNT; i++) {
        if (plr->tasks[i] == taskNum) {
            plr->tasks[i] = 0;
            for (int j = 0; j < 3; j++) {
                plr->RemainingNPCCount[i][j] = 0;
            }
        }
    }
    if (i == ACTIVE_MISSION_COUNT - 1 && plr->tasks[i] != 0) {
        std::cout << "[WARN] Player quit non-active mission!?" << std::endl;
    }
    // remove current mission
    plr->CurrentMissionID = 0;

    TaskData& task = *Tasks[taskNum];

    // clean up quest items
    if (manual) {
        for (i = 0; i < 3; i++) {
            if (task["m_iSUItem"][i] == 0 && task["m_iCSUItemID"][i] == 0)
                continue;

            /*
             * It's ok to do this only server-side, because the server decides which
             * slot later items will be placed in.
             */
            for (int j = 0; j < AQINVEN_COUNT; j++)
                if (plr->QInven[j].iID == task["m_iSUItem"][i] || plr->QInven[j].iID == task["m_iCSUItemID"][i] || plr->QInven[j].iID == task["m_iSTItemID"][i])
                    memset(&plr->QInven[j], 0, sizeof(sItemBase));
        }
    } else {
        INITSTRUCT(sP_FE2CL_REP_PC_TASK_END_FAIL, failResp);
        failResp.iErrorCode = 1;
        failResp.iTaskNum = taskNum;
        sock->sendPacket((void*)&failResp, P_FE2CL_REP_PC_TASK_END_FAIL, sizeof(sP_FE2CL_REP_PC_TASK_END_FAIL));
    }

    INITSTRUCT(sP_FE2CL_REP_PC_TASK_STOP_SUCC, response);
    response.iTaskNum = taskNum;
    sock->sendPacket((void*)&response, P_FE2CL_REP_PC_TASK_STOP_SUCC, sizeof(sP_FE2CL_REP_PC_TASK_STOP_SUCC));
}

void Missions::updateFusionMatter(CNSocket* sock, int fusion) {
    Player *plr = PlayerManager::getPlayer(sock);

    plr->fusionmatter += fusion;

    // there's a much lower FM cap in the Future
    int fmCap = AvatarGrowth[plr->level]["m_iFMLimit"];
    if (plr->fusionmatter > fmCap)
        plr->fusionmatter = fmCap;
    else if (plr->fusionmatter < 0) // if somehow lowered too far
        plr->fusionmatter = 0;

    // don't run nano mission logic at level 36
    if (plr->level >= 36)
        return;

    // don't give the Blossom nano mission until the player's in the Past
    if (plr->level == 4 && plr->PCStyle2.iPayzoneFlag == 0)
        return;

    // check if it is enough for the nano mission
    int fmNano = AvatarGrowth[plr->level]["m_iReqBlob_NanoCreate"];
    if (plr->fusionmatter < fmNano)
        return;

#ifndef ACADEMY
    // check if the nano task is already started
    for (int i = 0; i < ACTIVE_MISSION_COUNT; i++) {
        TaskData& task = *Tasks[plr->tasks[i]];
        if (task["m_iSTNanoID"] != 0)
            return; // nano mission was already started!
    }

    // start the nano mission
    startTask(plr, AvatarGrowth[plr->level]["m_iNanoQuestTaskID"]);

    INITSTRUCT(sP_FE2CL_REP_PC_TASK_START_SUCC, response);
    response.iTaskNum = AvatarGrowth[plr->level]["m_iNanoQuestTaskID"];
    sock->sendPacket((void*)&response, P_FE2CL_REP_PC_TASK_START_SUCC, sizeof(sP_FE2CL_REP_PC_TASK_START_SUCC));
#else
    if (plr->level >= 36)
        return;

    plr->fusionmatter -= (int)Missions::AvatarGrowth[plr->level]["m_iReqBlob_NanoCreate"];
    plr->level++;

    INITSTRUCT(sP_FE2CL_REP_PC_CHANGE_LEVEL_SUCC, response);

    response.iFusionMatter = plr->fusionmatter;
    response.iLevel = plr->level;

    sock->sendPacket((void*)&response, P_FE2CL_REP_PC_CHANGE_LEVEL_SUCC, sizeof(sP_FE2CL_REP_PC_CHANGE_LEVEL_SUCC));
#endif

    // play the beam animation for other players
    INITSTRUCT(sP_FE2CL_PC_EVENT, bcast);
    bcast.iEventID = 1; // beam effect
    bcast.iPC_ID = plr->iID;
    PlayerManager::sendToViewable(sock, (void*)&bcast, P_FE2CL_PC_EVENT, sizeof(sP_FE2CL_PC_EVENT));
}

void Missions::mobKilled(CNSocket *sock, int mobid, int rolledQItem) {
    Player *plr = PlayerManager::getPlayer(sock);

    bool missionmob = false;

    for (int i = 0; i < ACTIVE_MISSION_COUNT; i++) {
        if (plr->tasks[i] == 0)
            continue;

        // tasks[] should always have valid IDs
        TaskData& task = *Tasks[plr->tasks[i]];

        for (int j = 0; j < 3; j++) {
            if (task["m_iCSUEnemyID"][j] != mobid)
                continue;

            // acknowledge killing of mission mob...
            if (task["m_iCSUNumToKill"][j] != 0) {
                missionmob = true;
                if (plr->RemainingNPCCount[i][j] > 0) {
                    plr->RemainingNPCCount[i][j]--;
                }
            }
            // drop quest item
            if (task["m_iCSUItemNumNeeded"][j] != 0 && !isQuestItemFull(sock, task["m_iCSUItemID"][j], task["m_iCSUItemNumNeeded"][j]) ) {
                bool drop = rolledQItem % 100 < task["m_iSTItemDropRate"][j];
                if (drop) {
                    // XXX: are CSUItemID and CSTItemID the same?
                    dropQuestItem(sock, plr->tasks[i], 1, task["m_iCSUItemID"][j], mobid);
                } else {
                    // fail to drop (itemID == 0)
                    dropQuestItem(sock, plr->tasks[i], 1, 0, mobid);
                }
            }
        }
    }

    // ...but only once
    // XXX: is it actually necessary to do it this way?
    if (missionmob) {
        INITSTRUCT(sP_FE2CL_REP_PC_KILL_QUEST_NPCs_SUCC, kill);

        kill.iNPCID = mobid;

        sock->sendPacket((void*)&kill, P_FE2CL_REP_PC_KILL_QUEST_NPCs_SUCC, sizeof(sP_FE2CL_REP_PC_KILL_QUEST_NPCs_SUCC));
    }
}

void Missions::failInstancedMissions(CNSocket* sock) {
    // loop through all tasks; if the required instance is being left, "fail" the task
    Player* plr = PlayerManager::getPlayer(sock);
    for (int i = 0; i < 6; i++) {
        int taskNum = plr->tasks[i];
        if (Missions::Tasks.find(taskNum) == Missions::Tasks.end())
            continue; // sanity check

        TaskData* task = Missions::Tasks[taskNum];
        if (task->task["m_iRequireInstanceID"] != 0) { // mission is instanced
            int failTaskID = task->task["m_iFOutgoingTask"];
            if (failTaskID != 0) {
                Missions::quitTask(sock, taskNum, false);
                //plr->tasks[i] = failTaskID; // this causes the client to freak out and send a dupe task
            }
        }
    }
}

void Missions::init() {
    REGISTER_SHARD_PACKET(P_CL2FE_REQ_PC_TASK_START, taskStart);
    REGISTER_SHARD_PACKET(P_CL2FE_REQ_PC_TASK_END, taskEnd);
    REGISTER_SHARD_PACKET(P_CL2FE_REQ_PC_SET_CURRENT_MISSION_ID, setMission);
    REGISTER_SHARD_PACKET(P_CL2FE_REQ_PC_TASK_STOP, quitMission);
}