/*
Copyright (C) 1996-1997 Id Software, Inc.

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.

*/
// sv_user.c -- server code for moving users

#include "quakedef.h"

edict_t *sv_player;

extern  cvar_t  sv_friction;
cvar_t  sv_edgefriction = {"edgefriction", "2"};
extern  cvar_t  sv_stopspeed;

static  vec3_t    forward, right, up;

vec3_t  wishdir;
float wishspeed;

// world
float *angles;
float *origin;
float *velocity;

qboolean  onground;

usercmd_t cmd;

cvar_t  sv_idealpitchscale = {"sv_idealpitchscale","0.8"};


/*
===============
SV_SetIdealPitch
===============
*/
#define MAX_FORWARD 6
void SV_SetIdealPitch (void)
{
  float angleval, sinval, cosval;
  trace_t tr;
  vec3_t  top, bottom;
  float z[MAX_FORWARD];
  int   i, j;
  int   step, dir, steps;

  if (!((int)sv_player->v.flags & FL_ONGROUND))
    return;
    
  angleval = sv_player->v.angles[YAW] * M_PI*2 / 360;
  sinval = sin(angleval);
  cosval = cos(angleval);

  for (i=0 ; i<MAX_FORWARD ; i++)
  {
    top[0] = sv_player->v.origin[0] + cosval*(i+3)*12;
    top[1] = sv_player->v.origin[1] + sinval*(i+3)*12;
    top[2] = sv_player->v.origin[2] + sv_player->v.view_ofs[2];
    
    bottom[0] = top[0];
    bottom[1] = top[1];
    bottom[2] = top[2] - 160;
    
    tr = SV_Move (top, vec3_origin, vec3_origin, bottom, 1, sv_player);
    if (tr.allsolid)
      return; // looking at a wall, leave ideal the way is was

    if (tr.fraction == 1)
      return; // near a dropoff
    
    z[i] = top[2] + tr.fraction*(bottom[2]-top[2]);
  }
  
  dir = 0;
  steps = 0;
  for (j=1 ; j<i ; j++)
  {
    step = z[j] - z[j-1];
    if (step > -ON_EPSILON && step < ON_EPSILON)
      continue;

    if (dir && ( step-dir > ON_EPSILON || step-dir < -ON_EPSILON ) )
      return;   // mixed changes

    steps++;  
    dir = step;
  }
  
  if (!dir)
  {
    sv_player->v.idealpitch = 0;
    return;
  }
  
  if (steps < 2)
    return;
  sv_player->v.idealpitch = -dir * sv_idealpitchscale.value;
}


/*
==================
SV_UserFriction

==================
*/
void SV_UserFriction (void)
{
  float *vel;
  float speed, newspeed, control;
  vec3_t  start, stop;
  float friction;
  trace_t trace;
  
  vel = velocity;
  
  speed = sqrt(vel[0]*vel[0] +vel[1]*vel[1]);
  if (!speed)
    return;

// if the leading edge is over a dropoff, increase friction
  start[0] = stop[0] = origin[0] + vel[0]/speed*16;
  start[1] = stop[1] = origin[1] + vel[1]/speed*16;
  start[2] = origin[2] + sv_player->v.mins[2];
  stop[2] = start[2] - 34;

  trace = SV_Move (start, vec3_origin, vec3_origin, stop, true, sv_player);

  if (trace.fraction == 1.0)
    friction = sv_friction.value*sv_edgefriction.value;
  else
    friction = sv_friction.value;

// apply friction 
  control = speed < sv_stopspeed.value ? sv_stopspeed.value : speed;
  newspeed = speed - host_frametime*control*friction;
  
  if (newspeed < 0)
    newspeed = 0;
  newspeed /= speed;

  vel[0] = vel[0] * newspeed;
  vel[1] = vel[1] * newspeed;
  vel[2] = vel[2] * newspeed;
}

/*
==============
SV_Accelerate
==============
*/
cvar_t  sv_maxspeed = {"sv_maxspeed", "320", false, true};
cvar_t  sv_accelerate = {"sv_accelerate", "10"};
#if 0
void SV_Accelerate (vec3_t wishvel)
{
  int     i;
  float   addspeed, accelspeed;
  vec3_t    pushvec;

  if (wishspeed == 0)
    return;

  VectorSubtract (wishvel, velocity, pushvec);
  addspeed = VectorNormalize (pushvec);

  accelspeed = sv_accelerate.value*host_frametime*addspeed;
  if (accelspeed > addspeed)
    accelspeed = addspeed;
  
  for (i=0 ; i<3 ; i++)
    velocity[i] += accelspeed*pushvec[i]; 
}
#endif
void SV_Accelerate (void)
{
  int     i;
  float   addspeed, accelspeed, currentspeed;

  currentspeed = DotProduct (velocity, wishdir);
  addspeed = wishspeed - currentspeed;
  if (addspeed <= 0)
    return;
  accelspeed = sv_accelerate.value*host_frametime*wishspeed;
  if (accelspeed > addspeed)
    accelspeed = addspeed;
  
  for (i=0 ; i<3 ; i++)
    velocity[i] += accelspeed*wishdir[i]; 
}

void SV_AirAccelerate (vec3_t wishveloc)
{
  int     i;
  float   addspeed, wishspd, accelspeed, currentspeed;
    
  wishspd = VectorNormalize (wishveloc);
  if (wishspd > 30)
    wishspd = 30;
  currentspeed = DotProduct (velocity, wishveloc);
  addspeed = wishspd - currentspeed;
  if (addspeed <= 0)
    return;
//  accelspeed = sv_accelerate.value * host_frametime;
  accelspeed = sv_accelerate.value*wishspeed * host_frametime;
  if (accelspeed > addspeed)
    accelspeed = addspeed;
  
  for (i=0 ; i<3 ; i++)
    velocity[i] += accelspeed*wishveloc[i]; 
}


void DropPunchAngle (void)
{
  float len;
  
  len = VectorNormalize (sv_player->v.punchangle);
  
  len -= 10*host_frametime;
  if (len < 0)
    len = 0;
  VectorScale (sv_player->v.punchangle, len, sv_player->v.punchangle);
}

/*
===================
SV_WaterMove

===================
*/
void SV_WaterMove (void)
{
  int   i;
  vec3_t  wishvel;
  float speed, newspeed, wishspeed, addspeed, accelspeed;

//
// user intentions
//
  AngleVectors (sv_player->v.v_angle, forward, right, up);

  for (i=0 ; i<3 ; i++)
    wishvel[i] = forward[i]*cmd.forwardmove + right[i]*cmd.sidemove;

  if (!cmd.forwardmove && !cmd.sidemove && !cmd.upmove)
    wishvel[2] -= 60;   // drift towards bottom
  else
    wishvel[2] += cmd.upmove;

  wishspeed = Length(wishvel);
  if (wishspeed > sv_maxspeed.value)
  {
    VectorScale (wishvel, sv_maxspeed.value/wishspeed, wishvel);
    wishspeed = sv_maxspeed.value;
  }
  wishspeed *= 0.7;

//
// water friction
//
  speed = Length (velocity);
  if (speed)
  {
    newspeed = speed - host_frametime * speed * sv_friction.value;
    if (newspeed < 0)
      newspeed = 0; 
    VectorScale (velocity, newspeed/speed, velocity);
  }
  else
    newspeed = 0;
  
//
// water acceleration
//
  if (!wishspeed)
    return;

  addspeed = wishspeed - newspeed;
  if (addspeed <= 0)
    return;

  VectorNormalize (wishvel);
  accelspeed = sv_accelerate.value * wishspeed * host_frametime;
  if (accelspeed > addspeed)
    accelspeed = addspeed;

  for (i=0 ; i<3 ; i++)
    velocity[i] += accelspeed * wishvel[i];
}

void SV_WaterJump (void)
{
  if (sv.time > sv_player->v.teleport_time
  || !sv_player->v.waterlevel)
  {
    sv_player->v.flags = (int)sv_player->v.flags & ~FL_WATERJUMP;
    sv_player->v.teleport_time = 0;
  }
  sv_player->v.velocity[0] = sv_player->v.movedir[0];
  sv_player->v.velocity[1] = sv_player->v.movedir[1];
}


/*
===================
SV_AirMove

===================
*/
void SV_AirMove (void)
{
  int     i;
  vec3_t    wishvel;
  float   fmove, smove;

  AngleVectors (sv_player->v.angles, forward, right, up);

  fmove = cmd.forwardmove;
  smove = cmd.sidemove;
  
// hack to not let you back into teleporter
  if (sv.time < sv_player->v.teleport_time && fmove < 0)
    fmove = 0;
    
  for (i=0 ; i<3 ; i++)
    wishvel[i] = forward[i]*fmove + right[i]*smove;

  if ( (int)sv_player->v.movetype != MOVETYPE_WALK)
    wishvel[2] = cmd.upmove;
  else
    wishvel[2] = 0;

  VectorCopy (wishvel, wishdir);
  wishspeed = VectorNormalize(wishdir);
  if (wishspeed > sv_maxspeed.value)
  {
    VectorScale (wishvel, sv_maxspeed.value/wishspeed, wishvel);
    wishspeed = sv_maxspeed.value;
  }
  
  if ( sv_player->v.movetype == MOVETYPE_NOCLIP)
  { // noclip
    VectorCopy (wishvel, velocity);
  }
  else if ( onground )
  {
    SV_UserFriction ();
    SV_Accelerate ();
  }
  else
  { // not on ground, so little effect on velocity
    SV_AirAccelerate (wishvel);
  }   
}

/*
===================
SV_ClientThink

the move fields specify an intended velocity in pix/sec
the angle fields specify an exact angular motion in degrees
===================
*/
void SV_ClientThink (void)
{
  vec3_t    v_angle;

  if (sv_player->v.movetype == MOVETYPE_NONE)
    return;
  
  onground = (int)sv_player->v.flags & FL_ONGROUND;

  origin = sv_player->v.origin;
  velocity = sv_player->v.velocity;

  DropPunchAngle ();
  
//
// if dead, behave differently
//
  if (sv_player->v.health <= 0)
    return;

//
// angles
// show 1/3 the pitch angle and all the roll angle
  cmd = host_client->cmd;
  angles = sv_player->v.angles;
  
  VectorAdd (sv_player->v.v_angle, sv_player->v.punchangle, v_angle);
  angles[ROLL] = V_CalcRoll (sv_player->v.angles, sv_player->v.velocity)*4;
  if (!sv_player->v.fixangle)
  {
    angles[PITCH] = -v_angle[PITCH]/3;
    angles[YAW] = v_angle[YAW];
  }

  if ( (int)sv_player->v.flags & FL_WATERJUMP )
  {
    SV_WaterJump ();
    return;
  }
//
// walk
//
  if ( (sv_player->v.waterlevel >= 2)
  && (sv_player->v.movetype != MOVETYPE_NOCLIP) )
  {
    SV_WaterMove ();
    return;
  }

  SV_AirMove ();  
}


/*
===================
SV_ReadClientMove
===================
*/
void SV_ReadClientMove (usercmd_t *move)
{
  int   i;
  vec3_t  angle;
  int   bits;
  
// read ping time
  host_client->ping_times[host_client->num_pings%NUM_PING_TIMES]
    = sv.time - MSG_ReadFloat ();
  host_client->num_pings++;

// read current angles  
  for (i=0 ; i<3 ; i++)
    angle[i] = MSG_ReadAngle ();

  VectorCopy (angle, host_client->edict->v.v_angle);
    
// read movement
  move->forwardmove = MSG_ReadShort ();
  move->sidemove = MSG_ReadShort ();
  move->upmove = MSG_ReadShort ();
  
// read buttons
  bits = MSG_ReadByte ();
  host_client->edict->v.button0 = bits & 1;
  host_client->edict->v.button2 = (bits & 2)>>1;

  i = MSG_ReadByte ();
  if (i)
    host_client->edict->v.impulse = i;

#ifdef QUAKE2
// read light level
  host_client->edict->v.light_level = MSG_ReadByte ();
#endif
}

/*
===================
SV_ReadClientMessage

Returns false if the client should be killed
===================
*/
qboolean SV_ReadClientMessage (void)
{
  int   ret;
  int   cmd;
  char    *s;
  
  do
  {
nextmsg:
    ret = NET_GetMessage (host_client->netconnection);
    if (ret == -1)
    {
      Sys_Printf ("SV_ReadClientMessage: NET_GetMessage failed\n");
      return false;
    }
    if (!ret)
      return true;
          
    MSG_BeginReading ();
    
    while (1)
    {
      if (!host_client->active)
        return false; // a command caused an error

      if (msg_badread)
      {
        Sys_Printf ("SV_ReadClientMessage: badread\n");
        return false;
      } 
  
      cmd = MSG_ReadChar ();
      
      switch (cmd)
      {
      case -1:
        goto nextmsg;   // end of message
        
      default:
        Sys_Printf ("SV_ReadClientMessage: unknown command char\n");
        return false;
              
      case clc_nop:
//        Sys_Printf ("clc_nop\n");
        break;
        
      case clc_stringcmd: 
        s = MSG_ReadString ();
        if (host_client->privileged)
          ret = 2;
        else
          ret = 0;
        if (Q_strncasecmp(s, "status", 6) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "god", 3) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "notarget", 8) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "fly", 3) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "name", 4) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "noclip", 6) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "say", 3) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "say_team", 8) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "tell", 4) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "color", 5) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "kill", 4) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "pause", 5) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "spawn", 5) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "begin", 5) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "prespawn", 8) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "kick", 4) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "ping", 4) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "give", 4) == 0)
          ret = 1;
        else if (Q_strncasecmp(s, "ban", 3) == 0)
          ret = 1;
        if (ret == 2)
          Cbuf_InsertText (s);
        else if (ret == 1)
          Cmd_ExecuteString (s, src_client);
        else
          Con_DPrintf("%s tried to %s\n", host_client->name, s);
        break;
        
      case clc_disconnect:
//        Sys_Printf ("SV_ReadClientMessage: client disconnected\n");
        return false;
      
      case clc_move:
        SV_ReadClientMove (&host_client->cmd);
        break;
      }
    }
  } while (ret == 1);
  
  return true;
}


/*
==================
SV_RunClients
==================
*/
void SV_RunClients (void)
{
  int       i;
  
  for (i=0, host_client = svs.clients ; i<svs.maxclients ; i++, host_client++)
  {
    if (!host_client->active)
      continue;
  
    sv_player = host_client->edict;

    if (!SV_ReadClientMessage ())
    {
      SV_DropClient (false);  // client misbehaved...
      continue;
    }

    if (!host_client->spawned)
    {
    // clear client movement until a new packet is received
      memset (&host_client->cmd, 0, sizeof(host_client->cmd));
      continue;
    }

// always pause in single player if in console or menus
    if (!sv.paused && (svs.maxclients > 1 || key_dest == key_game) )
      SV_ClientThink ();
  }
}