/*
Copyright (C) 1997-2001 Id Software, Inc.
Copyright (C) 2000-2002 Mr. Hyde and Mad Dog

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.

*/

// m_move.c -- monster movement

#include "g_local.h"

#define	STEPSIZE	18

/*
=============
M_CheckBottom

Returns false if any part of the bottom of the entity is off an edge that
is not a staircase.

=============
*/
int c_yes, c_no;

qboolean M_CheckBottom (edict_t *ent)
{
	vec3_t	mins, maxs, start, stop;
	trace_t	trace;
	int		x, y;
	float	mid, bottom;
	
	VectorAdd (ent->s.origin, ent->mins, mins);
	VectorAdd (ent->s.origin, ent->maxs, maxs);

// if all of the points under the corners are solid world, don't bother
// with the tougher checks
// the corners must be within 16 of the midpoint
	start[2] = mins[2] - 1;
	for	(x=0 ; x<=1 ; x++)
		for	(y=0 ; y<=1 ; y++)
		{
			start[0] = x ? maxs[0] : mins[0];
			start[1] = y ? maxs[1] : mins[1];
			if (gi.pointcontents (start) != CONTENTS_SOLID)
				goto realcheck;
		}

	c_yes++;
	return true;		// we got out easy

realcheck:
	c_no++;
//
// check it for real...
//
	start[2] = mins[2];
	
// the midpoint must be within 16 of the bottom
	start[0] = stop[0] = (mins[0] + maxs[0])*0.5;
	start[1] = stop[1] = (mins[1] + maxs[1])*0.5;
	stop[2] = start[2] - 2*STEPSIZE;
	trace = gi.trace (start, vec3_origin, vec3_origin, stop, ent, MASK_MONSTERSOLID);

	if (trace.fraction == 1.0)
		return false;
	mid = bottom = trace.endpos[2];
	
// the corners must be within 16 of the midpoint	
	for	(x=0 ; x<=1 ; x++)
		for	(y=0 ; y<=1 ; y++)
		{
			start[0] = stop[0] = x ? maxs[0] : mins[0];
			start[1] = stop[1] = y ? maxs[1] : mins[1];
			
			trace = gi.trace (start, vec3_origin, vec3_origin, stop, ent, MASK_MONSTERSOLID);
			
			if (trace.fraction != 1.0 && trace.endpos[2] > bottom)
				bottom = trace.endpos[2];
			if (trace.fraction == 1.0 || mid - trace.endpos[2] > STEPSIZE)
				return false;
		}

	c_yes++;
	return true;
}


/*
=============
SV_movestep

Called by monster program code.
The move will be adjusted for slopes and stairs, but if the move isn't
possible, no move is done, false is returned, and
pr_global_struct->trace_normal is set to the normal of the blocking wall
=============
*/
//FIXME since we need to test end position contents here, can we avoid doing
//it again later in catagorize position?
qboolean SV_movestep (edict_t *ent, vec3_t move, qboolean relink)
{
	float		dz;
	vec3_t		oldorg, neworg, end;
	trace_t		trace;
	int			i;
	float		stepsize;
	float		jumpheight;
	vec3_t		test;
	int			contents;

	qboolean	canjump;
	float		d1, d2;
	int			jump;		// 1=jump up, -1=jump down
	vec3_t		forward, up;
	vec3_t		dir;
	vec_t		dist;
	vec_t		g1, g2;
	edict_t		*grenade;
	edict_t		*target;

	// try the move	
	VectorCopy (ent->s.origin, oldorg);
	VectorAdd (ent->s.origin, move, neworg);

	AngleVectors(ent->s.angles,forward,NULL,up);
	if(ent->enemy)
		target = ent->enemy;
	else if(ent->movetarget)
		target = ent->movetarget;
	else
		target = NULL;

	// flying monsters don't step up
	if ( ent->flags & (FL_SWIM | FL_FLY) )
	{
		// try one move with vertical motion, then one without
		for (i=0 ; i<2 ; i++)
		{
			VectorAdd (ent->s.origin, move, neworg);
			if (i == 0 && ent->enemy)
			{
				if (!ent->goalentity)
					ent->goalentity = ent->enemy;
				dz = ent->s.origin[2] - ent->goalentity->s.origin[2];
				if (ent->goalentity->client)
				{
					if (dz > 40)
						neworg[2] -= 8;
					if (!((ent->flags & FL_SWIM) && (ent->waterlevel < 2)))
						if (dz < 30)
							neworg[2] += 8;
				}
				else
				{
					if (dz > 8)
						neworg[2] -= 8;
					else if (dz > 0)
						neworg[2] -= dz;
					else if (dz < -8)
						neworg[2] += 8;
					else
						neworg[2] += dz;
				}
			}
			trace = gi.trace (ent->s.origin, ent->mins, ent->maxs, neworg, ent, MASK_MONSTERSOLID);
	
			// fly monsters don't enter water voluntarily
			if (ent->flags & FL_FLY)
			{
				if (!ent->waterlevel)
				{
					test[0] = trace.endpos[0];
					test[1] = trace.endpos[1];
					test[2] = trace.endpos[2] + ent->mins[2] + 1;
					contents = gi.pointcontents(test);
					if (contents & MASK_WATER)
						return false;
				}
			}

			// swim monsters don't exit water voluntarily
			if (ent->flags & FL_SWIM)
			{
				if (ent->waterlevel < 2)
				{
					test[0] = trace.endpos[0];
					test[1] = trace.endpos[1];
					test[2] = trace.endpos[2] + ent->mins[2] + 1;
					contents = gi.pointcontents(test);
					if (!(contents & MASK_WATER))
						return false;
				}
			}

			if (trace.fraction == 1)
			{
				VectorCopy (trace.endpos, ent->s.origin);
				if (relink)
				{
					gi.linkentity (ent);
					G_TouchTriggers (ent);
				}
				return true;
			}
			
			if (!ent->enemy)
				break;
		}
		
		return false;
	}

	// push down from a step height above the wished position
	if (!(ent->monsterinfo.aiflags & AI_NOSTEP))
		stepsize = STEPSIZE;
	else
		stepsize = 1;

	neworg[2] += stepsize;
	VectorCopy (neworg, end);
	end[2] -= stepsize*2;

	trace = gi.trace (neworg, ent->mins, ent->maxs, end, ent, MASK_MONSTERSOLID);

	// Determine whether monster is capable of and/or should jump
	jump = 0;
	if((ent->monsterinfo.jump) && !(ent->monsterinfo.aiflags & AI_DUCKED))
	{
		// Don't jump if path is blocked by monster or player. Otherwise,
		// monster might attempt to jump OVER the monster/player, which 
		// ends up looking a bit goofy. Also don't jump if the monster's
		// movement isn't deliberate (target=NULL)
		if(trace.ent && (trace.ent->client || (trace.ent->svflags & SVF_MONSTER)))
			canjump = false;
		else if(target)
		{
			// Never jump unless it places monster closer to his goal
			vec3_t	dir;
			VectorSubtract(target->s.origin, oldorg, dir);
			d1 = VectorLength(dir);
			VectorSubtract(target->s.origin, trace.endpos, dir);
			d2 = VectorLength(dir);
			if(d2 < d1)
				canjump = true;
			else
				canjump = false;
		}
		else
			canjump = false;
	}
	else
		canjump = false;

	if (trace.allsolid)
	{
		if(canjump && (ent->monsterinfo.jumpup > 0))
		{
			neworg[2] += ent->monsterinfo.jumpup - stepsize;
			trace = gi.trace (neworg, ent->mins, ent->maxs, end, ent, MASK_MONSTERSOLID);
			if (!trace.allsolid && !trace.startsolid && trace.fraction > 0 && (trace.plane.normal[2] > 0.9))
			{
				if(!trace.ent || (!trace.ent->client && !(trace.ent->svflags & SVF_MONSTER) && !(trace.ent->svflags & SVF_DEADMONSTER)))
				{
					// Good plane to jump on. Make sure monster is more or less facing
					// the obstacle to avoid cutting-corners jumps
					trace_t	tr;
					vec3_t	p2;

					VectorMA(ent->s.origin,1024,forward,p2);
					tr = gi.trace(ent->s.origin,ent->mins,ent->maxs,p2,ent,MASK_MONSTERSOLID);
					if(DotProduct(tr.plane.normal,forward) < -0.95)
					{
						jump = 1;
						jumpheight = trace.endpos[2] - ent->s.origin[2];
					}
					else
						return false;
				}
			}
			else
				return false;
		}
		else
			return false;
	}

	if (trace.startsolid)
	{
		neworg[2] -= stepsize;
		trace = gi.trace (neworg, ent->mins, ent->maxs, end, ent, MASK_MONSTERSOLID);
		if (trace.allsolid || trace.startsolid)
			return false;
	}


	// don't go in to water
	// Lazarus: misc_actors don't go swimming, but wading is fine
	if (ent->monsterinfo.aiflags & AI_ACTOR)
	{
		// First check for lava/slime under feet - but only if we're not already in
		// a liquid
		test[0] = trace.endpos[0];
		test[1] = trace.endpos[1];
		if (ent->waterlevel == 0)
		{
			test[2] = trace.endpos[2] + ent->mins[2] + 1;	
			contents = gi.pointcontents(test);
			if (contents & (CONTENTS_LAVA | CONTENTS_SLIME))
				return false;
		}
		test[2] = trace.endpos[2] + ent->viewheight - 1;
		contents = gi.pointcontents(test);
		if (contents & MASK_WATER)
			return false;
	}
	else if (ent->waterlevel == 0)
	{
		test[0] = trace.endpos[0];
		test[1] = trace.endpos[1];
		test[2] = trace.endpos[2] + ent->mins[2] + 1;	
		contents = gi.pointcontents(test);

		if (contents & MASK_WATER)
			return false;
	}

	// Lazarus: Don't intentionally move closer to a grenade,
	//          but don't perform this check if we're already evading some
	//          other problem (maybe even this grenade)
	if(!(ent->monsterinfo.aiflags & AI_CHASE_THING))
	{
		grenade = NULL;
		while( (grenade=findradius(grenade,neworg,128)) != NULL)
		{
			if(!grenade->inuse)
				continue;
			if(!grenade->classname)
				continue;
			if(!Q_stricmp(grenade->classname,"grenade") || !Q_stricmp(grenade->classname,"hgrenade"))
			{
				VectorSubtract(grenade->s.origin,oldorg,dir);
				g1 = VectorLength(dir);
				VectorSubtract(grenade->s.origin,neworg,dir);
				g2 = VectorLength(dir);
				if(g2 < g1)
					return false;
			}
		}
	}
	// Lazarus: Don't intentionally walk into lasers.
	dist = VectorLength(move);
	if(dist > 0.)
	{
		edict_t		*e;
		trace_t		laser_trace;
		vec_t		delta;
		vec3_t		laser_mins, laser_maxs;
		vec3_t		laser_start, laser_end;
		vec3_t		monster_mins, monster_maxs;

		for(i=game.maxclients+1; i<globals.num_edicts; i++)
		{
			e = &g_edicts[i];
			if(!e->inuse)
				continue;
			if(!e->classname)
				continue;
			if(Q_stricmp(e->classname,"target_laser"))
				continue;
			if(e->svflags & SVF_NOCLIENT)
				continue;
			if( (e->style == 2) || (e->style == 3))
				continue;
			if(!gi.inPVS(ent->s.origin,e->s.origin))
				continue;
			// Check to see if monster is ALREADY in the path of this laser.
			// If so, allow the move so he can get out.
			VectorMA(e->s.origin,2048,e->movedir,laser_end);
			laser_trace = gi.trace(e->s.origin,NULL,NULL,laser_end,NULL,CONTENTS_SOLID|CONTENTS_MONSTER);
			if(laser_trace.ent == ent)
				continue;
			VectorCopy(laser_trace.endpos,laser_end);
			laser_mins[0] = min(e->s.origin[0],laser_end[0]);
			laser_mins[1] = min(e->s.origin[1],laser_end[1]);
			laser_mins[2] = min(e->s.origin[2],laser_end[2]);
			laser_maxs[0] = max(e->s.origin[0],laser_end[0]);
			laser_maxs[1] = max(e->s.origin[1],laser_end[1]);
			laser_maxs[2] = max(e->s.origin[2],laser_end[2]);
			monster_mins[0] = min(oldorg[0],trace.endpos[0]) + ent->mins[0];
			monster_mins[1] = min(oldorg[1],trace.endpos[1]) + ent->mins[1];
			monster_mins[2] = min(oldorg[2],trace.endpos[2]) + ent->mins[2];
			monster_maxs[0] = max(oldorg[0],trace.endpos[0]) + ent->maxs[0];
			monster_maxs[1] = max(oldorg[1],trace.endpos[1]) + ent->maxs[1];
			monster_maxs[2] = max(oldorg[2],trace.endpos[2]) + ent->maxs[2];
			if( monster_maxs[0] < laser_mins[0] ) continue;
			if( monster_maxs[1] < laser_mins[1] ) continue;
			if( monster_maxs[2] < laser_mins[2] ) continue;
			if( monster_mins[0] > laser_maxs[0] ) continue;
			if( monster_mins[1] > laser_maxs[1] ) continue;
			if( monster_mins[2] > laser_maxs[2] ) continue;
			// If we arrive here, some part of the bounding box surrounding
			// monster's total movement intersects laser bounding box.
			// If laser is parallel to x, y, or z, we definitely
			// know this move will put monster in path of laser
			if ( (e->movedir[0] == 1.) || (e->movedir[1] == 1.) || (e->movedir[2] == 1.))
				return false;
			// Shift psuedo laser towards monster's current position up to
			// the total distance he's proposing moving.
			delta = min(16,dist);
			VectorNormalize2(move,dir);
			while(delta < dist+15.875)
			{
				if(delta > dist) delta = dist;
				VectorMA(e->s.origin,    -delta,dir,laser_start);
				VectorMA(e->s.old_origin,-delta,dir,laser_end);
				laser_trace = gi.trace(laser_start,NULL,NULL,laser_end,world,CONTENTS_SOLID|CONTENTS_MONSTER);
				if(laser_trace.ent == ent)
					return false;
				delta += 16;
			}
		}
	}
	if ((trace.fraction == 1) && !jump && canjump && (ent->monsterinfo.jumpdn > 0))
	{
		end[2] = oldorg[2] + move[2] - ent->monsterinfo.jumpdn;
		trace = gi.trace (neworg, ent->mins, ent->maxs, end, ent, MASK_MONSTERSOLID | MASK_WATER);
		if(trace.fraction < 1 && (trace.plane.normal[2] > 0.9) && (trace.contents & MASK_SOLID) && (neworg[2] - 16 > trace.endpos[2]))
		{
			if(!trace.ent || (!trace.ent->client && !(trace.ent->svflags & SVF_MONSTER) && !(trace.ent->svflags & SVF_DEADMONSTER)))
				jump = -1;
		}
	}


	if ((trace.fraction == 1) && !jump)
	{
		// if monster had the ground pulled out, go ahead and fall
		if ( ent->flags & FL_PARTIALGROUND )
		{
			VectorAdd (ent->s.origin, move, ent->s.origin);
			if (relink)
			{
				gi.linkentity (ent);
				G_TouchTriggers (ent);
			}
			ent->groundentity = NULL;
			return true;
		}
		return false;		// walked off an edge
	}

	// check point traces down for dangling corners
	VectorCopy (trace.endpos, ent->s.origin);

	if(!jump)
	{
		qboolean	skip = false;
		// if monster CAN jump down, and a position just a bit forward would be 
		// a good jump-down spot, allow (briefly) !M_CheckBottom
		if (canjump && target && (target->s.origin[2] < ent->s.origin[2]) && (ent->monsterinfo.jumpdn > 0))
		{
			vec3_t		p1, p2;
			trace_t		tr;

			VectorMA(oldorg,48,forward,p1);
			tr = gi.trace(ent->s.origin, ent->mins, ent->maxs, p1, ent, MASK_MONSTERSOLID);
			if(tr.fraction == 1)
			{
				p2[0] = p1[0];
				p2[1] = p1[1];
				p2[2] = p1[2] - ent->monsterinfo.jumpdn;
				tr = gi.trace(p1,ent->mins,ent->maxs,p2,ent,MASK_MONSTERSOLID | MASK_WATER);
				if(tr.fraction < 1 && (tr.plane.normal[2] > 0.9) && (tr.contents & MASK_SOLID) && (p1[2] - 16 > tr.endpos[2]))
				{
					if(!tr.ent || (!tr.ent->client && !(tr.ent->svflags & SVF_MONSTER) && !(tr.ent->svflags & SVF_DEADMONSTER)))
					{
						VectorSubtract(target->s.origin, tr.endpos, dir);
						d2 = VectorLength(dir);
						if(d2 < d1)
							skip = true;
					}
				}
			}

		}
		if (!skip)
		{
			if (!M_CheckBottom (ent))
			{
				if ( ent->flags & FL_PARTIALGROUND )
				{	// entity had floor mostly pulled out from underneath it
					// and is trying to correct
					if (relink)
					{
						gi.linkentity (ent);
						G_TouchTriggers (ent);
					}
					return true;
				}
				VectorCopy (oldorg, ent->s.origin);
				return false;
			}
		}
	}

	if ( ent->flags & FL_PARTIALGROUND )
	{
		ent->flags &= ~FL_PARTIALGROUND;
	}
	ent->groundentity = trace.ent;
	if(trace.ent)
		ent->groundentity_linkcount = trace.ent->linkcount;

// the move is ok
	if(jump)
	{
		VectorScale(move, 10, ent->velocity);
		if(jump > 0)
		{
			ent->monsterinfo.jump(ent);
			ent->velocity[2] = 2.5*jumpheight + 80;
		}
		else
		{
			ent->velocity[2] = max(ent->velocity[2],100);
			if(oldorg[2] - ent->s.origin[2] > 48)
				ent->s.origin[2] = oldorg[2] + ent->velocity[2]*FRAMETIME;
		}
		if(relink)
		{
			gi.linkentity (ent);
			G_TouchTriggers (ent);
		}
	}
	else if (relink)
	{
		gi.linkentity (ent);
		G_TouchTriggers (ent);
	}
	return true;
}


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

/*
===============
M_ChangeYaw

===============
*/
void M_ChangeYaw (edict_t *ent)
{
	float	ideal;
	float	current;
	float	move;
	float	speed;

	current = anglemod(ent->s.angles[YAW]);
	ideal = ent->ideal_yaw;

	if (current == ideal)
		return;

	move = ideal - current;
	speed = ent->yaw_speed;
	if (ideal > current)
	{
		if (move >= 180)
			move = move - 360;
	}
	else
	{
		if (move <= -180)
			move = move + 360;
	}
	if (move > 0)
	{
		if (move > speed)
			move = speed;
	}
	else
	{
		if (move < -speed)
			move = -speed;
	}

	ent->s.angles[YAW] = anglemod (current + move);
}


/*
======================
SV_StepDirection

Turns to the movement direction, and walks the current distance if
facing it.

======================
*/
qboolean SV_StepDirection (edict_t *ent, float yaw, float dist)
{
	vec3_t		move, oldorigin;
	float		delta;

	ent->ideal_yaw = yaw;
	M_ChangeYaw (ent);
	
	yaw = yaw*M_PI*2 / 360;
	move[0] = cos(yaw)*dist;
	move[1] = sin(yaw)*dist;
	move[2] = 0;

	VectorCopy (ent->s.origin, oldorigin);
	if (SV_movestep (ent, move, false))
	{
		delta = ent->s.angles[YAW] - ent->ideal_yaw;
		if (delta > 45 && delta < 315)
		{		// not turned far enough, so don't take the step
			VectorCopy (oldorigin, ent->s.origin);
		}
		gi.linkentity (ent);
		G_TouchTriggers (ent);
		return true;
	}
	gi.linkentity (ent);
	G_TouchTriggers (ent);
	return false;
}

/*
======================
SV_FixCheckBottom

======================
*/
void SV_FixCheckBottom (edict_t *ent)
{
	ent->flags |= FL_PARTIALGROUND;
}



/*
================
SV_NewChaseDir

================
*/
#define	DI_NODIR	-1
void SV_NewChaseDir (edict_t *actor, edict_t *enemy, float dist)
{
	float	deltax,deltay;
	float	d[3];
	float	tdir, olddir, turnaround;

	//FIXME: how did we get here with no enemy
	if (!enemy)
		return;

	if(actor->flags & FL_ROBOT)
		olddir = anglemod( (int)(actor->ideal_yaw+0.5) );
	else
		olddir = anglemod( (int)(actor->ideal_yaw/45)*45 );
	turnaround = anglemod(olddir - 180);

	deltax = enemy->s.origin[0] - actor->s.origin[0];
	deltay = enemy->s.origin[1] - actor->s.origin[1];

	if(actor->flags & FL_ROBOT)
	{
		d[1] = d[2] = olddir;
	}
	else
	{
		if (deltax>10)
			d[1]= 0;
		else if (deltax<-10)
			d[1]= 180;
		else
			d[1]= DI_NODIR;
		if (deltay<-10)
			d[2]= 270;
		else if (deltay>10)
			d[2]= 90;
		else
			d[2]= DI_NODIR;
	}

// try direct route
	if (d[1] != DI_NODIR && d[2] != DI_NODIR)
	{
		if(actor->flags & FL_ROBOT)
			tdir = d[1];
		else
		{
			if (d[1] == 0)
				tdir = d[2] == 90 ? 45 : 315;
			else
				tdir = d[2] == 90 ? 135 : 215;
		}
		if (tdir != turnaround && SV_StepDirection(actor, tdir, dist))
			return;
	}

	// Robots give up if direct path doesn't work
	if(actor->flags & FL_ROBOT)
	{
		actor->ideal_yaw = olddir;		// can't move
		if (!M_CheckBottom (actor))
			SV_FixCheckBottom (actor);
	}

// try other directions
	if ( ((rand()&3) & 1) ||  abs(deltay)>abs(deltax))
	{
		tdir=d[1];
		d[1]=d[2];
		d[2]=tdir;
	}
	if (d[1]!=DI_NODIR && d[1]!=turnaround 
	&& SV_StepDirection(actor, d[1], dist))
			return;

	if (d[2]!=DI_NODIR && d[2]!=turnaround
	&& SV_StepDirection(actor, d[2], dist))
			return;

	if (actor->inuse && (actor->health > 0) && actor->monsterinfo.blocked) {
		if (actor->monsterinfo.blocked(actor, dist))
			return;
	}


/* there is no direct path to the player, so pick another direction */

	if (olddir!=DI_NODIR && SV_StepDirection(actor, olddir, dist))
			return;

	if (rand()&1) 	/*randomly determine direction of search*/
	{
		for (tdir=0 ; tdir<=315 ; tdir += 45)
			if (tdir!=turnaround && SV_StepDirection(actor, tdir, dist) )
					return;
	}
	else
	{
		for (tdir=315 ; tdir >=0 ; tdir -= 45)
			if (tdir!=turnaround && SV_StepDirection(actor, tdir, dist) )
					return;
	}

	if (turnaround != DI_NODIR && SV_StepDirection(actor, turnaround, dist) )
			return;

	actor->ideal_yaw = olddir;		// can't move

// if a bridge was pulled out from underneath a monster, it may not have
// a valid standing position at all

	if (!M_CheckBottom (actor))
		SV_FixCheckBottom (actor);
}

/*
======================
SV_CloseEnough

======================
*/
qboolean SV_CloseEnough (edict_t *ent, edict_t *goal, float dist)
{
	int		i;

	for (i=0 ; i<3 ; i++)
	{
		if (goal->absmin[i] > ent->absmax[i] + dist)
			return false;
		if (goal->absmax[i] < ent->absmin[i] - dist)
			return false;
	}
	return true;
}


/*
======================
M_MoveToGoal
======================
*/
mmove_t actor_move_run;
mmove_t actor_move_stand;
mmove_t actor_move_walk;
void M_MoveToGoal (edict_t *ent, float dist)
{
	edict_t		*goal;
	
	goal = ent->goalentity;

	if (!ent->groundentity && !(ent->flags & (FL_FLY|FL_SWIM)))
		return;

	// Lazarus range checks
	if (!(ent->monsterinfo.aiflags & (AI_CHASE_THING | AI_CHICKEN)))
	{
		if (ent->enemy && (ent->monsterinfo.min_range > 0) && ((goal==ent->enemy) || !goal) ) {
			float dist;
			dist = realrange(ent,ent->enemy);
			if(dist < ent->monsterinfo.min_range)
			{
				ent->monsterinfo.aiflags |= (AI_STAND_GROUND | AI_RANGE_PAUSE);
				ent->monsterinfo.rangetime = level.time + 0.5;
				ent->monsterinfo.stand(ent);
				return;
			}
		}
		if ((ent->enemy) && (level.time > ent->monsterinfo.rangetime + 0.5) && ((goal==ent->enemy) || !goal) )
		{
			float dist;
			dist = realrange(ent,ent->enemy);
			if((dist < ent->monsterinfo.ideal_range[0]) && (rand() & 3))
			{
				ent->monsterinfo.aiflags |= (AI_STAND_GROUND | AI_RANGE_PAUSE);
				ent->monsterinfo.rangetime = level.time + 1.0;
				ent->monsterinfo.stand(ent);
				return;
			}
			if((dist < ent->monsterinfo.ideal_range[1]) && (dist > ent->monsterinfo.ideal_range[0]) && (rand() & 1))
			{
				ent->monsterinfo.aiflags |= (AI_STAND_GROUND | AI_RANGE_PAUSE);
				ent->monsterinfo.rangetime = level.time + 0.2;
				ent->monsterinfo.stand(ent);
				return;
			}
		}
	}

	if( (ent->monsterinfo.aiflags & AI_FOLLOW_LEADER) &&
		(ent->movetarget) &&
		(ent->movetarget->inuse) &&
		(ent->movetarget->health > 0) ) {

		if(ent->enemy)
			ent->monsterinfo.currentmove = &actor_move_run;
		else
		{
			float	R;

			R = realrange(ent,ent->movetarget);
			if(R > ACTOR_FOLLOW_RUN_RANGE)
				ent->monsterinfo.currentmove = &actor_move_run;
			else if(R < ACTOR_FOLLOW_STAND_RANGE && ent->movetarget->client) {
				ent->monsterinfo.pausetime = level.time + 0.5;
				ent->monsterinfo.currentmove = &actor_move_stand;
				return;
			}
			else
				ent->monsterinfo.currentmove = &actor_move_walk;
		}
	}

//	If the next step hits the enemy, return immediately. Don't do this for
//	AI_CHASE_THING, since we want monster to actually touch or pass through
//	"thing"
	if (ent->enemy && !(ent->monsterinfo.aiflags & AI_CHASE_THING) && SV_CloseEnough (ent, ent->enemy, dist) )
		return;

// bump around...
	if ( (rand()&3)==1 || !SV_StepDirection (ent, ent->ideal_yaw, dist))
	{
		if (ent->inuse)
			SV_NewChaseDir (ent, goal, dist);
	}
}


/*
===============
M_walkmove
===============
*/
qboolean M_walkmove (edict_t *ent, float yaw, float dist)
{
	vec3_t	move;
	
	if (!ent->groundentity && !(ent->flags & (FL_FLY|FL_SWIM)))
		return false;

	yaw = yaw*M_PI*2 / 360;
	
	move[0] = cos(yaw)*dist;
	move[1] = sin(yaw)*dist;
	move[2] = 0;

	return SV_movestep(ent, move, true);
}

