/* Emacs style mode select   -*- C++ -*-
 *-----------------------------------------------------------------------------
 *
 *
 *  PrBoom a Doom port merged with LxDoom and LSDLDoom
 *  based on BOOM, a modified and improved DOOM engine
 *  Copyright (C) 1999 by
 *  id Software, Chi Hoang, Lee Killough, Jim Flynn, Rand Phares, Ty Halderman
 *  Copyright (C) 1999-2000 by
 *  Jess Haas, Nicolas Kalkhof, Colin Phipps, Florian Schulze
 *
 *  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.
 *
 *  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., 59 Temple Place - Suite 330, Boston, MA
 *  02111-1307, USA.
 *
 * DESCRIPTION:
 *      Player related stuff.
 *      Bobbing POV/weapon, movement.
 *      Pending weapon.
 *
 *-----------------------------------------------------------------------------*/

#include "doomstat.h"
#include "d_event.h"
#include "r_main.h"
#include "p_map.h"
#include "p_spec.h"
#include "p_user.h"
#include "rockmacros.h"
// Index of the special effects (INVUL inverse) map.

#define INVERSECOLORMAP 32

//
// Movement.
//

// 16 pixels of bob

#define MAXBOB  0x100000

boolean onground; // whether player is on ground or in air

//
// P_Thrust
// Moves the given origin along a given angle.
//

void P_Thrust(player_t* player,angle_t angle,fixed_t move)
{
   angle >>= ANGLETOFINESHIFT;
   player->mo->momx += FixedMul(move,finecosine[angle]);
   player->mo->momy += FixedMul(move,finesine[angle]);
}


/*
 * P_Bob
 * Same as P_Thrust, but only affects bobbing.
 *
 * killough 10/98: We apply thrust separately between the real physical player
 * and the part which affects bobbing. This way, bobbing only comes from player
 * motion, nothing external, avoiding many problems, e.g. bobbing should not
 * occur on conveyors, unless the player walks on one, and bobbing should be
 * reduced at a regular rate, even on ice (where the player coasts).
 */

void P_Bob(player_t *player, angle_t angle, fixed_t move)
{
   player->momx += FixedMul(move,finecosine[angle >>= ANGLETOFINESHIFT]);
   player->momy += FixedMul(move,finesine[angle]);
}

//
// P_CalcHeight
// Calculate the walking / running height adjustment
//

void P_CalcHeight (player_t* player)
{
   int     angle;
   fixed_t bob;

   // Regular movement bobbing
   // (needs to be calculated for gun swing
   // even if not on ground)
   // OPTIMIZE: tablify angle
   // Note: a LUT allows for effects
   //  like a ramp with low health.


   /* killough 10/98: Make bobbing depend only on player-applied motion.
    *
    * Note: don't reduce bobbing here if on ice: if you reduce bobbing here,
    * it causes bobbing jerkiness when the player moves from ice to non-ice,
    * and vice-versa.
    */
   player->bob = !mbf_features ?
                 (FixedMul (player->mo->momx, player->mo->momx)
                  + FixedMul (player->mo->momy,player->mo->momy))>>2 :
                 player_bobbing ? (FixedMul(player->momx,player->momx) +
                                   FixedMul(player->momy,player->momy))>>2 : 0;

   if (player->bob > MAXBOB)
      player->bob = MAXBOB;

   if (!onground || player->cheats & CF_NOMOMENTUM)
   {
      player->viewz = player->mo->z + VIEWHEIGHT;

      if (player->viewz > player->mo->ceilingz-4*FRACUNIT)
         player->viewz = player->mo->ceilingz-4*FRACUNIT;

      // The following line was in the Id source and appears      // phares 2/25/98
      // to be a bug. player->viewz is checked in a similar
      // manner at a different exit below.

      //  player->viewz = player->mo->z + player->viewheight;
      return;
   }

   angle = (FINEANGLES/20*leveltime)&FINEMASK;
   bob = FixedMul(player->bob/2,finesine[angle]);

   // move viewheight

   if (player->playerstate == PST_LIVE)
   {
      player->viewheight += player->deltaviewheight;

      if (player->viewheight > VIEWHEIGHT)
      {
         player->viewheight = VIEWHEIGHT;
         player->deltaviewheight = 0;
      }

      if (player->viewheight < VIEWHEIGHT/2)
      {
         player->viewheight = VIEWHEIGHT/2;
         if (player->deltaviewheight <= 0)
            player->deltaviewheight = 1;
      }

      if (player->deltaviewheight)
      {
         player->deltaviewheight += FRACUNIT/4;
         if (!player->deltaviewheight)
            player->deltaviewheight = 1;
      }
   }

   player->viewz = player->mo->z + player->viewheight + bob;

   if (player->viewz > player->mo->ceilingz-4*FRACUNIT)
      player->viewz = player->mo->ceilingz-4*FRACUNIT;
}


//
// P_MovePlayer
//
// Adds momentum if the player is not in the air
//
// killough 10/98: simplified

void P_MovePlayer (player_t* player)
{
   ticcmd_t *cmd = &player->cmd;
   mobj_t *mo = player->mo;

   mo->angle += cmd->angleturn << 16;
   onground = mo->z <= mo->floorz;

   // killough 10/98:
   //
   // We must apply thrust to the player and bobbing separately, to avoid
   // anomalies. The thrust applied to bobbing is always the same strength on
   // ice, because the player still "works just as hard" to move, while the
   // thrust applied to the movement varies with 'movefactor'.

   if (cmd->forwardmove | cmd->sidemove) // killough 10/98
   {
      if (onground || mo->flags & MF_BOUNCES) // killough 8/9/98
      {
         int friction, movefactor = P_GetMoveFactor(mo, &friction);

         // killough 11/98:
         // On sludge, make bobbing depend on efficiency.
         // On ice, make it depend on effort.

         int bobfactor =
            friction < ORIG_FRICTION ? movefactor : ORIG_FRICTION_FACTOR;

         if (cmd->forwardmove)
         {
            P_Bob(player,mo->angle,cmd->forwardmove*bobfactor);
            P_Thrust(player,mo->angle,cmd->forwardmove*movefactor);
         }

         if (cmd->sidemove)
         {
            P_Bob(player,mo->angle-ANG90,cmd->sidemove*bobfactor);
            P_Thrust(player,mo->angle-ANG90,cmd->sidemove*movefactor);
         }
      }
      if (mo->state == states+S_PLAY)
         P_SetMobjState(mo,S_PLAY_RUN1);
   }
}

#define ANG5 (ANG90/18)

//
// P_DeathThink
// Fall on your face when dying.
// Decrease POV height to floor height.
//

void P_DeathThink (player_t* player)
{
   angle_t angle;
   angle_t delta;

   P_MovePsprites (player);

   // fall to the ground

   if (player->viewheight > 6*FRACUNIT)
      player->viewheight -= FRACUNIT;

   if (player->viewheight < 6*FRACUNIT)
      player->viewheight = 6*FRACUNIT;

   player->deltaviewheight = 0;
   onground = (player->mo->z <= player->mo->floorz);
   P_CalcHeight (player);

   if (player->attacker && player->attacker != player->mo)
   {
      angle = R_PointToAngle2 (player->mo->x,
                               player->mo->y,
                               player->attacker->x,
                               player->attacker->y);

      delta = angle - player->mo->angle;

      if (delta < ANG5 || delta > (unsigned)-ANG5)
      {
         // Looking at killer,
         //  so fade damage flash down.

         player->mo->angle = angle;

         if (player->damagecount)
            player->damagecount--;
      }
      else if (delta < ANG180)
         player->mo->angle += ANG5;
      else
         player->mo->angle -= ANG5;
   }
   else if (player->damagecount)
      player->damagecount--;

   if (player->cmd.buttons & BT_USE)
      player->playerstate = PST_REBORN;
}


//
// P_PlayerThink
//

void P_PlayerThink (player_t* player)
{
   ticcmd_t*    cmd;
   weapontype_t newweapon;

   // killough 2/8/98, 3/21/98:
   if (player->cheats & CF_NOCLIP)
      player->mo->flags |= MF_NOCLIP;
   else
      player->mo->flags &= ~MF_NOCLIP;

   // chain saw run forward

   cmd = &player->cmd;
   if (player->mo->flags & MF_JUSTATTACKED)
   {
      cmd->angleturn = 0;
      cmd->forwardmove = 0xc800/512;
      cmd->sidemove = 0;
      player->mo->flags &= ~MF_JUSTATTACKED;
   }

   if (player->playerstate == PST_DEAD)
   {
      P_DeathThink (player);
      return;
   }

   // Move around.
   // Reactiontime is used to prevent movement
   //  for a bit after a teleport.

   if (player->mo->reactiontime)
      player->mo->reactiontime--;
   else
      P_MovePlayer (player);

   P_CalcHeight (player); // Determines view height and bobbing

   // Determine if there's anything about the sector you're in that's
   // going to affect you, like painful floors.

   if (player->mo->subsector->sector->special)
      P_PlayerInSpecialSector (player);

   // Check for weapon change.

   if (cmd->buttons & BT_CHANGE)
   {
      // The actual changing of the weapon is done
      //  when the weapon psprite can do it
      //  (read: not in the middle of an attack).

      newweapon = (cmd->buttons & BT_WEAPONMASK)>>BT_WEAPONSHIFT;

      // killough 3/22/98: For demo compatibility we must perform the fist
      // and SSG weapons switches here, rather than in G_BuildTiccmd(). For
      // other games which rely on user preferences, we must use the latter.

      if (demo_compatibility)
      { // compatibility mode -- required for old demos -- killough
         if (newweapon == wp_fist && player->weaponowned[wp_chainsaw] &&
               (player->readyweapon != wp_chainsaw ||
                !player->powers[pw_strength]))
            newweapon = wp_chainsaw;
         if (gamemode == commercial &&
               newweapon == wp_shotgun &&
               player->weaponowned[wp_supershotgun] &&
               player->readyweapon != wp_supershotgun)
            newweapon = wp_supershotgun;
      }

      // killough 2/8/98, 3/22/98 -- end of weapon selection changes

      if (player->weaponowned[newweapon] && newweapon != player->readyweapon)

         // Do not go to plasma or BFG in shareware,
         //  even if cheated.

         if ((newweapon != wp_plasma && newweapon != wp_bfg)
               || (gamemode != shareware) )
            player->pendingweapon = newweapon;
   }

   // check for use

   if (cmd->buttons & BT_USE)
   {
      if (!player->usedown)
      {
         P_UseLines (player);
         player->usedown = true;
      }
   }
   else
      player->usedown = false;

   // cycle psprites

   P_MovePsprites (player);

   // Counters, time dependent power ups.

   // Strength counts up to diminish fade.

   if (player->powers[pw_strength])
      player->powers[pw_strength]++;

   // killough 1/98: Make idbeholdx toggle:

   if (player->powers[pw_invulnerability] > 0) // killough
      player->powers[pw_invulnerability]--;

   if (player->powers[pw_invisibility] > 0)    // killough
      if (! --player->powers[pw_invisibility] )
         player->mo->flags &= ~MF_SHADOW;

   if (player->powers[pw_infrared] > 0)        // killough
      player->powers[pw_infrared]--;

   if (player->powers[pw_ironfeet] > 0)        // killough
      player->powers[pw_ironfeet]--;

   if (player->damagecount)
      player->damagecount--;

   if (player->bonuscount)
      player->bonuscount--;

   // Handling colormaps.
   // killough 3/20/98: reformat to terse C syntax

   player->fixedcolormap = player->powers[pw_invulnerability] > 4*32 ||
                           player->powers[pw_invulnerability] & 8 ? INVERSECOLORMAP :
                           player->powers[pw_infrared] > 4*32 || player->powers[pw_infrared] & 8;
}