//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005-2014 Simon Howard
//
// 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.
//
// DESCRIPTION:
//	Plats (i.e. elevator platforms) code, raising/lowering.
//

#include <stdio.h>

#include "i_system.h"
#include "z_zone.h"
#include "m_random.h"

#include "doomdef.h"
#include "p_local.h"

#include "s_sound.h"

// State.
#include "doomstat.h"
#include "r_state.h"

// Data.
#include "sounds.h"


plat_t* activeplats[MAXPLATS];



//
// Move a plat up and down
//
void T_PlatRaise(plat_t* plat)
{
    result_e	res;

    switch(plat->status)
    {
    case up:
        res = T_MovePlane(plat->sector, plat->speed, plat->high, plat->crush, 0, 1);

        if(plat->type == raiseAndChange
            || plat->type == raiseToNearestAndChange)
        {
            if(!(leveltime&7))
                S_StartSound(&plat->sector->soundorg, sfx_stnmov);
        }

        // villsa [STRIFE]
        if(plat->type == slowDWUS)
        {
            if(!(leveltime&7))
                S_StartSound(&plat->sector->soundorg, sfx_stnmov);
        }


        if(res == crushed && (!plat->crush))
        {
            plat->count = plat->wait;
            plat->status = down;
            S_StartSound(&plat->sector->soundorg, sfx_pstart);
        }
        else
        {
            if(res == pastdest)
            {
                plat->count = plat->wait;
                plat->status = waiting;
                S_StartSound(&plat->sector->soundorg, sfx_pstop);

                switch(plat->type)
                {
                case blazeDWUS:
                case downWaitUpStay:
                case raiseAndChange:
                case slowDWUS:  // villsa [STRIFE]
                case raiseToNearestAndChange:
                    P_RemoveActivePlat(plat);
                    break;

                default:
                    break;
                }
            }
        }
        break;

    case down:
        res = T_MovePlane(plat->sector, plat->speed, plat->low, false, 0, -1);

        // villsa [STRIFE]
        if(plat->type == slowDWUS)
        {
            if(!(leveltime&7))
                S_StartSound(&plat->sector->soundorg, sfx_stnmov);
        }

        if(res == pastdest)
        {
            plat->count = plat->wait;
            plat->status = waiting;
            S_StartSound(&plat->sector->soundorg,sfx_pstop);

            // villsa [STRIFE]
            if(plat->type == upWaitDownStay)
                P_RemoveActivePlat(plat);
        }
        break;

    case waiting:
        if(!--plat->count)
        {
            if(plat->sector->floorheight == plat->low)
                plat->status = up;
            else
                plat->status = down;
            S_StartSound(&plat->sector->soundorg,sfx_pstart);
        }

    case in_stasis:
        break;
    }
}


//
// EV_DoPlat
//
// Do Platforms "amount" is only used for SOME platforms.
//
int EV_DoPlat(line_t* line, plattype_e type, int amount)
{
    plat_t*     plat;
    int         secnum;
    int         rtn;
    sector_t*   sec;

    secnum = -1;
    rtn = 0;


    //	Activate all <type> plats that are in_stasis
    switch(type)
    {
    case perpetualRaise:
        P_ActivateInStasis(line->tag);
        break;

    default:
        break;
    }

    while((secnum = P_FindSectorFromLineTag(line,secnum)) >= 0)
    {
        sec = &sectors[secnum];

        if (sec->specialdata)
            continue;

        // Find lowest & highest floors around sector
        rtn = 1;
        plat = Z_Malloc( sizeof(*plat), PU_LEVSPEC, 0);
        P_AddThinker(&plat->thinker);

        plat->type = type;
        plat->sector = sec;
        plat->sector->specialdata = plat;
        plat->thinker.function.acp1 = (actionf_p1) T_PlatRaise;
        plat->crush = false;
        plat->tag = line->tag;

        switch(type)
        {
        case raiseToNearestAndChange:
            plat->speed = PLATSPEED/2;
            sec->floorpic = sides[line->sidenum[0]].sector->floorpic;
            plat->high = P_FindNextHighestFloor(sec,sec->floorheight);
            plat->wait = 0;
            plat->status = up;

            // NO MORE DAMAGE, IF APPLICABLE
            sec->special = 0;		

            S_StartSound(&sec->soundorg, sfx_stnmov);
            break;

        case raiseAndChange:
            plat->speed = PLATSPEED/2;
            sec->floorpic = sides[line->sidenum[0]].sector->floorpic;
            plat->high = sec->floorheight + amount * FRACUNIT;
            plat->wait = 0;
            plat->status = up;

            S_StartSound(&sec->soundorg, sfx_stnmov);
            break;

            // villsa [STRIFE]
        case upWaitDownStay:
            plat->speed = PLATSPEED * 4;
            plat->high = P_FindNextHighestFloor(sec, sec->floorheight);
            plat->low = sec->floorheight;
            plat->wait = TICRATE * PLATWAIT;
            plat->status = up;
            S_StartSound(&sec->soundorg, sfx_pstart);
            break;

        case downWaitUpStay:
            plat->speed = PLATSPEED * 4;
            plat->low = P_FindLowestFloorSurrounding(sec);

            if(plat->low > sec->floorheight)
                plat->low = sec->floorheight;

            plat->high = sec->floorheight;
            plat->wait = TICRATE * PLATWAIT;
            plat->status = down;
            S_StartSound(&sec->soundorg, sfx_pstart);
            break;

            // villsa [STRIFE]
        case slowDWUS:
            plat->speed = PLATSPEED;
            plat->low = P_FindLowestFloorSurrounding(sec);

            if(plat->low > sec->floorheight)
                plat->low = sec->floorheight;

            plat->high = sec->floorheight;
            plat->wait = TICRATE * (PLATWAIT * 10);
            plat->status = down;
            S_StartSound(&sec->soundorg,sfx_pstart);
            break;

        case blazeDWUS:
            plat->speed = PLATSPEED * 8;
            plat->low = P_FindLowestFloorSurrounding(sec);

            if(plat->low > sec->floorheight)
                plat->low = sec->floorheight;

            plat->high = sec->floorheight;
            plat->wait = TICRATE * PLATWAIT;
            plat->status = down;
            S_StartSound(&sec->soundorg, sfx_pstart);
            break;

        case perpetualRaise:
            plat->speed = PLATSPEED;
            plat->low = P_FindLowestFloorSurrounding(sec);

            if(plat->low > sec->floorheight)
                plat->low = sec->floorheight;

            plat->high = P_FindHighestFloorSurrounding(sec);

            if(plat->high < sec->floorheight)
                plat->high = sec->floorheight;

            plat->wait = TICRATE * PLATWAIT;
            plat->status = P_Random() & 1;

            S_StartSound(&sec->soundorg, sfx_pstart);
            break;
        }

        P_AddActivePlat(plat);
    }
    return rtn;
}


//
// P_ActivateInStasis
//
void P_ActivateInStasis(int tag)
{
    int i;

    for(i = 0; i < MAXPLATS; i++)
        if(activeplats[i]
        && (activeplats[i])->tag == tag
            && (activeplats[i])->status == in_stasis)
        {
            (activeplats[i])->status = (activeplats[i])->oldstatus;
            (activeplats[i])->thinker.function.acp1
                = (actionf_p1)T_PlatRaise;
        }
}

//
// EV_StopPlat
//
void EV_StopPlat(line_t* line)
{
    int j;

    for(j = 0; j < MAXPLATS; j++)
        if (activeplats[j]
        && ((activeplats[j])->status != in_stasis)
            && ((activeplats[j])->tag == line->tag))
        {
            (activeplats[j])->oldstatus = (activeplats[j])->status;
            (activeplats[j])->status = in_stasis;
            (activeplats[j])->thinker.function.acv = (actionf_v)NULL;
        }
}

//
// P_AddActivePlat
//
void P_AddActivePlat(plat_t* plat)
{
    int i;

    for(i = 0; i < MAXPLATS; i++)
        if (activeplats[i] == NULL)
        {
            activeplats[i] = plat;
            return;
        }

        I_Error("P_AddActivePlat: no more plats!");
}

//
// P_RemoveActivePlat
//
void P_RemoveActivePlat(plat_t* plat)
{
    int i;
    for(i = 0; i < MAXPLATS; i++)
        if(plat == activeplats[i])
        {
            (activeplats[i])->sector->specialdata = NULL;
            P_RemoveThinker(&(activeplats[i])->thinker);
            activeplats[i] = NULL;

            return;
        }

        I_Error("P_RemoveActivePlat: can't find plat!");
}