//-------------------------------------------------------------------------
/*
Copyright (C) 2010-2019 EDuke32 developers and contributors
Copyright (C) 2019 sirlemonhead, Nuke.YKT
This file is part of PCExhumed.
PCExhumed is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License version 2
as published by the Free Software Foundation.
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.
*/
//-------------------------------------------------------------------------
#include "ns.h"
#include "engine.h"
#include "rat.h"
#include "sequence.h"
#include "runlist.h"
#include "random.h"
#include "view.h"
#include "init.h"
#include "exhumed.h"
#include "move.h"
#include <assert.h>

BEGIN_PS_NS

#define kMaxRats	50

short nMinChunk;
short nPlayerPic; // why is this here?
short nRatCount;
short nMaxChunk;

struct Rat
{
    short a;
    short nAction;
    short nSprite;
    short d;
    short nTarget;
    short f;
    short g;
    short _pad;
};

Rat RatList[kMaxRats];

static actionSeq ActionSeq[] = { { 0, 1}, {1, 0}, {1, 0}, {9, 1}, {0, 1} };


void InitRats()
{
    nRatCount = 0;
    nMinChunk = 9999;
    nMaxChunk = -1;

    for (int i = 122; i < 131; i++)
    {
        int nPic = seq_GetSeqPicnum(kSeqJoe, i, 0);

        if (nPic < nMinChunk)
            nMinChunk = nPic;

        if (nPic > nMaxChunk)
            nMaxChunk = nPic;
    }

    nPlayerPic = seq_GetSeqPicnum(kSeqJoe, 120, 0);
}

void SetRatVel(short nSprite)
{
    sprite[nSprite].xvel = (short)Sin(sprite[nSprite].ang + 512) >> 2;
    sprite[nSprite].yvel = (short)Sin(sprite[nSprite].ang) >> 2;
}

int BuildRat(short nSprite, int x, int y, int z, short nSector, int nAngle)
{
    if (nRatCount >= kMaxRats) {
        return -1;
    }

    short nRat = nRatCount++;

    if (nSprite < 0)
    {
        nSprite = insertsprite(nSector, 108);
        assert(nSprite >= 0 && nSprite < kMaxSprites);

        sprite[nSprite].x = x;
        sprite[nSprite].y = y;
        sprite[nSprite].z = z;
    }
    else
    {
        sprite[nSprite].ang = nAngle;
        changespritestat(nSprite, 108);
    }

    sprite[nSprite].cstat = 0x101;
    sprite[nSprite].shade = -12;
    sprite[nSprite].xoffset = 0;
    sprite[nSprite].yoffset = 0;
    sprite[nSprite].picnum = 1;
    sprite[nSprite].pal = sector[sprite[nSprite].sectnum].ceilingpal;
    sprite[nSprite].clipdist = 30;
    sprite[nSprite].ang = nAngle;
    sprite[nSprite].xrepeat = 50;
    sprite[nSprite].yrepeat = 50;
    sprite[nSprite].yvel = 0;
    sprite[nSprite].xvel = 0;
    sprite[nSprite].zvel = 0;
    sprite[nSprite].lotag = runlist_HeadRun() + 1;
    sprite[nSprite].hitag = 0;
    sprite[nSprite].extra = -1;

    if (nAngle >= 0) {
        RatList[nRat].nAction = 2;
    }
    else {
        RatList[nRat].nAction = 4;
    }

    RatList[nRat].a = 0;
    RatList[nRat].nSprite = nSprite;
    RatList[nRat].nTarget = -1;
    RatList[nRat].f = RandomSize(5);
    RatList[nRat].g = RandomSize(3);

    sprite[nSprite].owner = runlist_AddRunRec(sprite[nSprite].lotag - 1, nRat | 0x240000);

    RatList[nRat].d = runlist_AddRunRec(NewRun, nRat | 0x240000);
    return 0;
}

int FindFood(short nSprite)
{
    short nSector = sprite[nSprite].sectnum;
    int x = sprite[nSprite].x;
    int y = sprite[nSprite].y;
    int z = sprite[nSprite].z;

    int z2 = z + sector[nSector].ceilingz;

    if (nChunkTotal)
    {
        int nSprite2 = nChunkSprite[RandomSize(7) % nChunkTotal];
        if (nSprite2 != -1)
        {
            if (cansee(x, y, z2, nSector, sprite[nSprite2].x, sprite[nSprite2].y, sprite[nSprite2].z, sprite[nSprite2].sectnum)) {
                return nSprite2;
            }
        }
    }

    if (!nBodyTotal) {
        return -1;
    }

    int nSprite2 = nChunkSprite[RandomSize(7) % nBodyTotal];
    if (nSprite2 != -1)
    {
        if (nPlayerPic == sprite[nSprite2].picnum)
        {
            if (cansee(x, y, z, nSector, sprite[nSprite2].x, sprite[nSprite2].y, sprite[nSprite2].z, sprite[nSprite2].sectnum)) {
                return nSprite2;
            }
        }
    }

    return -1;
}

void FuncRat(int a, int nDamage, int nRun)
{
    short nRat = RunData[nRun].nVal;
    short nSprite = RatList[nRat].nSprite;

    short nAction = RatList[nRat].nAction;

    int var_20 = 0;

    int nMessage = a & 0x7F0000;

    switch (nMessage)
    {
        default:
        {
            Printf("unknown msg %d for Rathead\n", nMessage);
            return;
        }

        case 0xA0000:
        {
            nDamage = runlist_CheckRadialDamage(nSprite);
            // fall through to 0x80000
        }
        case 0x80000:
        {
            if (nDamage)
            {
                sprite[nSprite].cstat = 0;
                sprite[nSprite].yvel = 0;
                sprite[nSprite].xvel = 0;
                RatList[nRat].nAction = 3;
                RatList[nRat].a = 0;
            }
            break;
        }

        case 0x90000:
        {
            seq_PlotSequence(a, SeqOffsets[kSeqRat] + ActionSeq[nAction].a, RatList[nRat].a, ActionSeq[nAction].b);
            return;
        }

        case 0x20000:
        {
            int nSeq = SeqOffsets[kSeqRat] + ActionSeq[nAction].a;
            sprite[nSprite].picnum = seq_GetSeqPicnum2(nSeq, RatList[nRat].a);

            seq_MoveSequence(nSprite, nSeq, RatList[nRat].a);

            RatList[nRat].a++;
            if (RatList[nRat].a >= SeqSize[nSeq])
            {
                var_20 = 1;
                RatList[nRat].a = 0;
            }

            short nTarget = RatList[nRat].nTarget;

            Gravity(nSprite);

            switch (nAction)
            {
                default:
                {
                    return;
                }

                case 0:
                {
                    RatList[nRat].f--;
                    if (RatList[nRat].f > 0) {
                        return;
                    }

                    int xVal = sprite[nSprite].x - sprite[nTarget].x;
                    if (xVal < 0) {
                        xVal = -xVal;
                    }

                    int yVal = sprite[nSprite].y - sprite[nTarget].y;
                    if (yVal < 0) {
                        yVal = -yVal;
                    }

                    if (xVal > 50 || yVal > 50)
                    {
                        RatList[nRat].nAction = 2;
                        RatList[nRat].a = 0;
                        RatList[nRat].nTarget = -1;

                        sprite[nSprite].yvel = 0;
                        sprite[nSprite].xvel = 0;
                        return;
                    }

                    RatList[nRat].a ^= 1;
                    RatList[nRat].f = RandomSize(5) + 4;
                    RatList[nRat].g--;

                    if (RatList[nRat].g <= 0)
                    {
                        short nFoodSprite = FindFood(nSprite);
                        if (nFoodSprite == -1) {
                            return;
                        }

                        RatList[nRat].nTarget = nFoodSprite;

                        PlotCourseToSprite(nSprite, nFoodSprite);
                        SetRatVel(nSprite);

                        RatList[nRat].nAction = 1;
                        RatList[nRat].g = 900;
                        RatList[nRat].a = 0;
                    }

                    return;
                }
                case 1:
                {
                    RatList[nRat].g--;

                    if (RatList[nRat].g <= 0)
                    {
                        RatList[nRat].nAction = 2;
                        RatList[nRat].a = 0;
                        sprite[nSprite].yvel = 0;
                        RatList[nRat].nTarget = -1;
                        sprite[nSprite].xvel = 0;
                    }

                    MoveCreature(nSprite);

                    int xVal = sprite[nSprite].x - sprite[nTarget].x;
                    if (xVal < 0) {
                        xVal = -xVal;
                    }

                    int yVal = sprite[nSprite].y - sprite[nTarget].y;
                    if (yVal < 0) {
                        yVal = -yVal;
                    }

                    if (xVal >= 50 || yVal >= 50)
                    {
                        RatList[nRat].f--;
                        if (RatList[nRat].f < 0)
                        {
                            PlotCourseToSprite(nSprite, nTarget);
                            SetRatVel(nSprite);

                            RatList[nRat].f = 32;
                        }

                        return;
                    }

                    RatList[nRat].nAction = 0;
                    RatList[nRat].a = 0;

                    sprite[nSprite].yvel = 0;
                    sprite[nSprite].xvel = 0;

                    RatList[nRat].g = RandomSize(3);
                    return;
                }
                case 2:
                {
                    if (sprite[nSprite].xvel | sprite[nSprite].yvel | sprite[nSprite].zvel) {
                        MoveCreature(nSprite);
                    }

                    RatList[nRat].f--;
                    if (RatList[nRat].f <= 0)
                    {
                        RatList[nRat].nTarget = FindFood(nSprite);

                        if (RatList[nRat].nTarget <= -1)
                        {
                            RatList[nRat].f = RandomSize(6);
                            if (sprite[nSprite].xvel | sprite[nSprite].yvel)
                            {
                                sprite[nSprite].yvel = 0;
                                sprite[nSprite].xvel = 0;
                                return;
                            }

                            sprite[nSprite].ang = RandomSize(11);
                            SetRatVel(nSprite);
                            return;
                        }
                        else
                        {
                            PlotCourseToSprite(nSprite, RatList[nRat].nTarget);
                            SetRatVel(nSprite);
                            RatList[nRat].nAction = 1;
                            RatList[nRat].g = 900;
                            RatList[nRat].a = 0;
                            return;
                        }
                    }

                    return;
                }
                case 3:
                {
                    if (var_20 != 0)
                    {
                        runlist_DoSubRunRec(sprite[nSprite].owner);
                        runlist_FreeRun(sprite[nSprite].lotag - 1);
                        runlist_SubRunRec(RatList[nRat].d);

                        sprite[nSprite].cstat = 0x8000;
                        mydeletesprite(nSprite);
                    }
                    return;
                }
            }

            break;
        }
    }
}
END_PS_NS