/*  Copyright (C) 1996-2022 id Software LLC

    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

    See file, 'COPYING', for details.
*/

void() T_MissileTouch;
void() info_player_start;
void(entity targ, entity attacker) ClientObituary;
void(entity who) ResistanceSound;

//============================================================================

/*
============
CanDamage

Returns true if the inflictor can directly damage the target.  Used for
explosions and melee attacks.
============
*/
float(entity targ, entity inflictor) CanDamage =
{
// bmodels need special checking because their origin is 0,0,0
  if (targ.movetype == MOVETYPE_PUSH)
  {
    traceline(inflictor.origin, 0.5 * (targ.absmin + targ.absmax), TRUE, self);
    if (trace_fraction == 1)
      return TRUE;
    if (trace_ent == targ)
      return TRUE;
    return FALSE;
  }
  
  traceline(inflictor.origin, targ.origin, TRUE, self);
  if (trace_fraction == 1)
    return TRUE;
  traceline(inflictor.origin, targ.origin + '15 15 0', TRUE, self);
  if (trace_fraction == 1)
    return TRUE;
  traceline(inflictor.origin, targ.origin + '-15 -15 0', TRUE, self);
  if (trace_fraction == 1)
    return TRUE;
  traceline(inflictor.origin, targ.origin + '-15 15 0', TRUE, self);
  if (trace_fraction == 1)
    return TRUE;
  traceline(inflictor.origin, targ.origin + '15 -15 0', TRUE, self);
  if (trace_fraction == 1)
    return TRUE;

  return FALSE;
};


/*
============
Killed
============
*/
void(entity targ, entity attacker) Killed =
{
  local entity oself;

  oself = self;
  self = targ;
  
  if (self.health < -99)
    self.health = -99;    // don't let sbar look bad if a player

  if (self.movetype == MOVETYPE_PUSH || self.movetype == MOVETYPE_NONE)
  { // doors, triggers, etc

    self.th_die ();
    self = oself;
    return;
  }

  self.enemy = attacker;

// bump the monster counter
  if (self.flags & FL_MONSTER)
  {
    killed_monsters = killed_monsters + 1;
    WriteByte (MSG_ALL, SVC_KILLEDMONSTER);
  }

  ClientObituary(self, attacker);
  
  self.takedamage = DAMAGE_NO;
  self.touch = SUB_Null;

//  removed monsters
//  monster_death_use();
  self.th_die ();
  
  self = oself;
};


// *TEAMPLAY*
// Prototypes

float(entity targ, entity inflictor, entity attacker, float damage) TeamArmorDam;
float(entity targ, entity inflictor, entity attacker, float damage) TeamHealthDam;

/*
============
T_Damage

The damage is coming from inflictor, but get mad at attacker
This should be the only function that ever reduces health.
============
*/
void(entity targ, entity inflictor, entity attacker, float damage) T_Damage=
{
  local vector  dir;
  local entity  oldself;
  local float save;
  local float take;

  if (!targ.takedamage)
    return;

// used by buttons and triggers to set activator for target firing
  damage_attacker = attacker;

// check for quad damage powerup on the attacker
  if (attacker.super_damage_finished > time)
    damage = damage * 4;
// RUNE: check for double damage for rune of Black Magic powerup
  if (attacker.player_flag & ITEM_RUNE2_FLAG)
    damage = damage * 2;
// RUNE

//RUNE check if target has rune of Earth Magic (half damage)
  if (targ.player_flag & ITEM_RUNE1_FLAG) {
    damage = damage / 2;
    ResistanceSound(targ);
  }
//RUNE

  // *XXX* EXPERT CTF mark players who hurt the flag carrier, so they 
  // are worth more points for a while.
  if ( (attacker.classname == "player") && // attacker must be a player
       (targ.player_flag & ITEM_ENEMY_FLAG) && // target is a flag carrier
       (attacker.lastteam != targ.lastteam) && // target and attacker on diff teams
       (targ.lastteam > 0) ) // unconnected check?
    attacker.last_hurt_carrier = time;
 
// save damage based on the target's armor level

// *TEAMPLAY*
// TeamArmorDam returns true iff the attacker can damage the target's armor

  if (TeamArmorDam(targ, inflictor, attacker, damage))
    save = ceil(targ.armortype*damage);
  else
    save = 0;

  if (save >= targ.armorvalue)
  {
    save = targ.armorvalue;
    targ.armortype = 0; // lost all armor
    targ.items = targ.items - (targ.items & (IT_ARMOR1 | IT_ARMOR2 | IT_ARMOR3));
  }
  
  targ.armorvalue = targ.armorvalue - save;
  take = ceil(damage-save);

// add to the damage total for clients, which will be sent as a single
// message at the end of the frame
// FIXME: remove after combining shotgun blasts?
  if (targ.flags & FL_CLIENT)
  {
    targ.dmg_take = targ.dmg_take + take;
    targ.dmg_save = targ.dmg_save + save;
    targ.dmg_inflictor = inflictor;
  }

// figure momentum add
  if ( (inflictor != world) && (targ.movetype == MOVETYPE_WALK) )
  {
    dir = targ.origin - (inflictor.absmin + inflictor.absmax) * 0.5;
    dir = normalize(dir);
    targ.velocity = targ.velocity + dir*damage*8;
  }

// check for godmode or invincibility
  if (targ.team == targ.lastteam) { // 666 or god mode doesn't save ya
    if (targ.flags & FL_GODMODE)
      return;
    if (targ.invincible_finished >= time)
    {
      if (self.invincible_sound < time)
      {
        sound (targ, CHAN_ITEM, "items/protect3.wav", 1, ATTN_NORM);
        self.invincible_sound = time + 2;
      }
      return;
    }
  }

// team play damage avoidance
  if ( (teamplay == 1) && (targ.team > 0)&&(targ.team == attacker.team) )
    return;
    
// *TEAMPLAY*
// TeamHealthDam will return true if the attacker can damage the target's
// health

        if (!TeamHealthDam(targ, inflictor, attacker, damage))
                return;
    
// do the damage
  targ.health = targ.health - take;

  if (targ.health <= 0)
  {
    Killed (targ, attacker);
    return;
  }

// react to the damage
  oldself = self;
  self = targ;

  if (self.th_pain)
    self.th_pain (attacker, take);

  self = oldself;
};

/*
============
T_RadiusDamage
============
*/
void(entity inflictor, entity attacker, float damage, entity ignore) T_RadiusDamage =
{
  local float   points;
  local entity  head;
  local vector  org;

  head = findradius(inflictor.origin, damage+40);
  
  while (head)
  {
    if (head != ignore)
    {
      if (head.takedamage)
      {
        org = head.origin + (head.mins + head.maxs)*0.5;
        points = 0.5*vlen (inflictor.origin - org);
        if (points < 0)
          points = 0;
        points = damage - points;
        if (head == attacker)
          points = points * 0.5;
        if (points > 0)
        {
          if (CanDamage (head, inflictor))
          { // shambler takes half damage from all explosions
            if (head.classname == "monster_shambler")           
              T_Damage (head, inflictor, attacker, points*0.5);
            else
              T_Damage (head, inflictor, attacker, points);
          }
        }
      }
    }
    head = head.chain;
  }
};

/*
============
T_BeamDamage
============
*/
void(entity attacker, float damage) T_BeamDamage =
{
  local float   points;
  local entity  head;
  
  head = findradius(attacker.origin, damage+40);
  
  while (head)
  {
    if (head.takedamage)
    {
      points = 0.5*vlen (attacker.origin - head.origin);
      if (points < 0)
        points = 0;
      points = damage - points;
      if (head == attacker)
        points = points * 0.5;
      if (points > 0)
      {
        if (CanDamage (head, attacker))
        {
          if (head.classname == "monster_shambler")           
            T_Damage (head, attacker, attacker, points*0.5);
          else
            T_Damage (head, attacker, attacker, points);
        }
      }
    }
    head = head.chain;
  }
};