//========= Copyright © 1996-2005, Valve Corporation, All rights reserved. ============//
//
// Purpose: 
//
// $NoKeywords: $
//=============================================================================//


#include "cbase.h"

#include "game.h"			
#include "ndebugoverlay.h"

#include "ai_basenpc.h"
#include "ai_hull.h"
#include "ai_node.h"
#include "ai_motor.h"
#include "ai_navigator.h"
#include "ai_hint.h"
#include "scripted.h"

// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"

//=============================================================================
// PATHING & HIGHER LEVEL MOVEMENT
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
// Purpose: Static debug function to force all selected npcs to go to the 
//			given node
// Input  :
// Output :
//-----------------------------------------------------------------------------
void CAI_BaseNPC::ForceSelectedGo(CBaseEntity *pPlayer, const Vector &targetPos, const Vector &traceDir, bool bRun) 
{
	CAI_BaseNPC *npc = gEntList.NextEntByClass( (CAI_BaseNPC *)NULL );
	for ( ; npc; npc = gEntList.NextEntByClass(npc) )
	{
		if ( ( npc->m_debugOverlays & OVERLAY_NPC_SELECTED_BIT ) == 0 )
			continue;

		// If a behavior is active, we need to stop running it
		npc->SetPrimaryBehavior( NULL );

		Vector chasePosition = targetPos;
		npc->TranslateNavGoal( pPlayer, chasePosition );
		// It it legal to drop me here
		Vector	vUpBit = chasePosition;
		vUpBit.z += 1;

		trace_t tr;
		AI_TraceHull( chasePosition, vUpBit, npc->GetHullMins(), 
			npc->GetHullMaxs(), npc->GetAITraceMask(), npc, COLLISION_GROUP_NONE, &tr );
		if (tr.startsolid || tr.fraction != 1.0 )
		{
			NDebugOverlay::BoxAngles(chasePosition, npc->GetHullMins(), 
				npc->GetHullMaxs(), npc->GetAbsAngles(), 255,0,0,20,0.5);
		}

		npc->m_vecLastPosition = chasePosition;

		if (npc->m_hCine != NULL)
		{
			npc->ExitScriptedSequence();
		}

		npc->SetSchedule( bRun ? SCHED_FORCED_GO_RUN : SCHED_FORCED_GO );
		npc->m_flMoveWaitFinished = gpGlobals->curtime;
	}
}

//-----------------------------------------------------------------------------
// Purpose: Static debug function to make all selected npcs run around
// Input  :
// Output :
//-----------------------------------------------------------------------------
void CAI_BaseNPC::ForceSelectedGoRandom(void) 
{
	CAI_BaseNPC *npc = gEntList.NextEntByClass( (CAI_BaseNPC *)NULL );

	while (npc)
	{
		if (npc->m_debugOverlays & OVERLAY_NPC_SELECTED_BIT) 
		{
			// If a behavior is active, we need to stop running it
			npc->SetPrimaryBehavior( NULL );
			npc->SetSchedule( SCHED_RUN_RANDOM );
			npc->GetNavigator()->SetMovementActivity(ACT_RUN);
		}
		npc = gEntList.NextEntByClass(npc);
	}
}

//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::ScheduledMoveToGoalEntity( int scheduleType, CBaseEntity *pGoalEntity, Activity movementActivity )
{
	// If a behavior is active, we need to stop running it
	SetPrimaryBehavior( NULL );

	if ( m_NPCState == NPC_STATE_NONE )
	{
		// More than likely being grabbed before first think. Set ideal state to prevent schedule stomp
		m_NPCState = m_IdealNPCState;
	}

	SetSchedule( scheduleType );

	SetGoalEnt( pGoalEntity );

	// HACKHACK: Call through TranslateNavGoal to fixup this goal position
	// UNDONE: Remove this and have NPCs that need this functionality fix up paths in the 
	// movement system instead of when they are specified.
	AI_NavGoal_t goal(pGoalEntity->GetAbsOrigin(), movementActivity, AIN_DEF_TOLERANCE, AIN_YAW_TO_DEST);

	TranslateNavGoal( pGoalEntity, goal.dest );
	
	return GetNavigator()->SetGoal( goal );
}

//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::ScheduledFollowPath( int scheduleType, CBaseEntity *pPathStart, Activity movementActivity )
{
	// If a behavior is active, we need to stop running it
	SetPrimaryBehavior( NULL );

	if ( m_NPCState == NPC_STATE_NONE )
	{
		// More than likely being grabbed before first think. Set ideal state to prevent schedule stomp
		m_NPCState = m_IdealNPCState;
	}

	SetSchedule( scheduleType );

	SetGoalEnt( pPathStart );

	// HACKHACK: Call through TranslateNavGoal to fixup this goal position
	AI_NavGoal_t goal(GOALTYPE_PATHCORNER, pPathStart->GetLocalOrigin(), movementActivity, AIN_DEF_TOLERANCE, AIN_YAW_TO_DEST);

	TranslateNavGoal( pPathStart, goal.dest );

	return GetNavigator()->SetGoal( goal );
}

//-----------------------------------------------------------------------------
// Purpose:
// Input  :
// Output :
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::IsMoving( void ) 
{ 
	return GetNavigator()->IsGoalSet(); 
}


//-----------------------------------------------------------------------------

bool CAI_BaseNPC::IsCurTaskContinuousMove()
{
	const Task_t* pTask = GetTask();

	// This bit of logic strikes me funny, but the case does exist. (sjb)
	if( !pTask )
		return true;

	switch( pTask->iTask )
	{
	case TASK_WAIT_FOR_MOVEMENT:
	case TASK_MOVE_TO_TARGET_RANGE:
	case TASK_MOVE_TO_GOAL_RANGE:
	case TASK_WEAPON_RUN_PATH:
	case TASK_PLAY_SCENE:
	case TASK_RUN_PATH_TIMED:
	case TASK_WALK_PATH_TIMED:
	case TASK_RUN_PATH_FOR_UNITS:
	case TASK_WALK_PATH_FOR_UNITS:
	case TASK_RUN_PATH_FLEE:
	case TASK_WALK_PATH_WITHIN_DIST:
	case TASK_RUN_PATH_WITHIN_DIST:
		return true;
		break;

	default:
		return false;
		break;
	}
}


//-----------------------------------------------------------------------------
// Purpose: Used to specify that the NPC has a reason not to use the a navigation node
// Input  :
// Output :
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::IsUnusableNode(int iNodeID, CAI_Hint *pHint)
{
	if ( m_bHintGroupNavLimiting && m_strHintGroup != NULL_STRING && STRING(m_strHintGroup)[0] != 0 )
	{
		if (!pHint || pHint->GetGroup() != GetHintGroup())
		{
			return true;
		}
	}
	return false;
}

//-----------------------------------------------------------------------------
// Purpose: Checks the validity of the given route's goaltype
// Input  :
// Output :
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::ValidateNavGoal()
{
	if (GetNavigator()->GetGoalType() == GOALTYPE_COVER)
	{
		// Check if this location will block my enemy's line of sight to me
		if (GetEnemy())
		{
			Activity nCoverActivity = GetCoverActivity( GetHintNode() );
			Vector	 vCoverLocation = GetNavigator()->GetGoalPos();


			// For now we have to drop the node to the floor so we can
			// get an accurate postion of the NPC.  Should change once Ken checks in
			float floorZ = GetFloorZ(vCoverLocation);
			vCoverLocation.z = floorZ;


			Vector vEyePos = vCoverLocation + EyeOffset(nCoverActivity);

			if (!IsCoverPosition( GetEnemy()->EyePosition(), vEyePos ) )
			{
				TaskFail(FAIL_BAD_PATH_GOAL);
				return false;
			}
		}
	}
	return true;
}



//-----------------------------------------------------------------------------
// Purpose:
// Input  :
// Output :
//-----------------------------------------------------------------------------
float CAI_BaseNPC::OpenDoorAndWait( CBaseEntity *pDoor )
{
	float flTravelTime = 0;

	//DevMsg( 2, "A door. ");
	if (pDoor && !pDoor->IsLockedByMaster())
	{
		pDoor->Use(this, this, USE_ON, 0.0);
		flTravelTime = pDoor->GetMoveDoneTime();
		if ( pDoor->GetEntityName() != NULL_STRING )
		{
			CBaseEntity *pTarget = NULL;
			for (;;)
			{
				pTarget = gEntList.FindEntityByName( pTarget, pDoor->GetEntityName() );

				if ( pTarget != pDoor )
				{
					if ( !pTarget )
						break;

					if ( FClassnameIs( pTarget, pDoor->GetClassname() ) )
					{
						pTarget->Use(this, this, USE_ON, 0.0);
					}
				}
			}
		}
	}

	return gpGlobals->curtime + flTravelTime;
}

//-----------------------------------------------------------------------------

bool CAI_BaseNPC::CanStandOn( CBaseEntity *pSurface ) const
{
	if ( !pSurface->IsAIWalkable() )
	{
		return false;
	}

	CAI_Navigator *pNavigator = const_cast<CAI_Navigator *>(GetNavigator());

	if ( pNavigator->IsGoalActive() && 
		 pSurface == pNavigator->GetGoalTarget() )
		return false;

	return BaseClass::CanStandOn( pSurface );
}

//-----------------------------------------------------------------------------

bool CAI_BaseNPC::IsJumpLegal( const Vector &startPos, const Vector &apex, const Vector &endPos, 
							   float maxUp, float maxDown, float maxDist ) const
{
	if ((endPos.z - startPos.z) > maxUp + 0.1) 
		return false;
	if ((startPos.z - endPos.z) > maxDown + 0.1) 
		return false;

	if ((apex.z - startPos.z) > maxUp * 1.25 ) 
		return false;

	float dist = (startPos - endPos).Length();
	if ( dist > maxDist + 0.1) 
		return false;
	return true;
}

//-----------------------------------------------------------------------------
// Purpose: Returns true if a reasonable jumping distance
// Input  :
// Output :
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::IsJumpLegal( const Vector &startPos, const Vector &apex, const Vector &endPos ) const
{
	const float MAX_JUMP_RISE		= 80.0f;
	const float MAX_JUMP_DISTANCE	= 250.0f;
	const float MAX_JUMP_DROP		= 192.0f;

	return IsJumpLegal( startPos, apex, endPos, MAX_JUMP_RISE, MAX_JUMP_DROP, MAX_JUMP_DISTANCE );
}

//-----------------------------------------------------------------------------
// Purpose: Returns a throw velocity from start to end position
// Input  :
// Output :
//-----------------------------------------------------------------------------
Vector CAI_BaseNPC::CalcThrowVelocity(const Vector &startPos, const Vector &endPos, float fGravity, float fArcSize) 
{
	// Get the height I have to throw to get to the target
	float stepHeight = endPos.z - startPos.z;
	float throwHeight = 0;

	// -----------------------------------------------------------------
	// Now calcluate the distance to a point halfway between our current
	// and target position.  (the apex of our throwing arc)
	// -----------------------------------------------------------------
	Vector targetDir2D = endPos - startPos;
	targetDir2D.z = 0;

	float distance = VectorNormalize(targetDir2D);


	// If jumping up we want to throw a bit higher than the height diff	
	if (stepHeight > 0) 
	{
		throwHeight = stepHeight + fArcSize;	
	}	
	else
	{
		throwHeight = fArcSize;
	}
	// Make sure that I at least catch some air
	if (throwHeight < fArcSize)
	{
		throwHeight = fArcSize;
	}


	// -------------------------------------------------------------
	// calculate the vertical and horizontal launch velocities
	// -------------------------------------------------------------
	float velVert = (float)sqrt(2.0f*fGravity*throwHeight);

	float divisor = velVert;
	divisor += (float)sqrt((2.0f*(-fGravity)*(stepHeight-throwHeight)));

	float velHorz = (distance * fGravity)/divisor;

	// -----------------------------------------------------------
	// Make the horizontal throw vector and add vertical component
	// -----------------------------------------------------------
	Vector throwVel = targetDir2D * velHorz;
	throwVel.z = velVert;

	return throwVel;
}

bool CAI_BaseNPC::ShouldMoveWait()
{
	return (m_flMoveWaitFinished > gpGlobals->curtime);
}

float CAI_BaseNPC::GetStepDownMultiplier() const
{
	return m_pNavigator->GetStepDownMultiplier();
}


//-----------------------------------------------------------------------------
// Purpose: execute any movement this sequence may have
// Output :
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::AutoMovement( CBaseEntity *pTarget, AIMoveTrace_t *pTraceResult )
{
	return AutoMovement( GetAnimTimeInterval(), pTarget, pTraceResult );
}

//-----------------------------------------------------------------------------
// Purpose: 
// Input  : flInterval - 
//			 - 
//			*pTraceResult - 
// Output : Returns true on success, false on failure.
//-----------------------------------------------------------------------------
bool CAI_BaseNPC::AutoMovement( float flInterval, CBaseEntity *pTarget, AIMoveTrace_t *pTraceResult )
{
	bool ignored;
	Vector newPos;
	QAngle newAngles;

	if (flInterval <= 0.0)
		return true;

	m_ScheduleState.bTaskRanAutomovement = true;

	if (GetIntervalMovement( flInterval, ignored, newPos, newAngles ))
	{
		// DevMsg( "%.2f : (%.1f) %.1f %.1f %.1f\n", gpGlobals->curtime, (newPos - GetLocalOrigin()).Length(), newPos.x, newPos.y, newAngles.y );
	
		if ( m_hCine )
		{
			m_hCine->ModifyScriptedAutoMovement( &newPos );
		}

		if (GetMoveType() == MOVETYPE_STEP)
		{
			if (!(GetFlags() & FL_FLY))
			{
				if ( !pTarget )
				{
					pTarget = GetNavTargetEntity();
				}

				// allow NPCs to adjust the automatic movement
				if ( ModifyAutoMovement( newPos ) )
				{
					// Set our motor's speed here
					Vector vecOriginalPosition = GetAbsOrigin();
					bool bResult = false;
					if (!TaskIsComplete())
					{
						bResult = ( GetMotor()->MoveGroundStep( newPos, pTarget, newAngles.y, false, true, pTraceResult ) == AIM_SUCCESS );
					}

					Vector change = GetAbsOrigin() - vecOriginalPosition;
					if (flInterval != 0)
					{
						change /= flInterval;
					}

					GetMotor()->SetMoveVel(change);

					return bResult;
				}

				return ( GetMotor()->MoveGroundStep( newPos, pTarget, newAngles.y, false, true, pTraceResult ) == AIM_SUCCESS );
			}
			else
			{
				// FIXME: here's no direct interface to a fly motor, plus this needs to support a state where going through the world is okay.
				// FIXME: add callbacks into the script system for validation
				// FIXME: add function on scripts to force only legal movements
				// FIXME: GetIntervalMovement deals in Local space, nor global.  Currently now way to communicate that through these interfaces.
				SetLocalOrigin( newPos );
				SetLocalAngles( newAngles );
				return true;
			}
		}
		else if (GetMoveType() == MOVETYPE_FLY)
		{
			Vector dist = newPos - GetLocalOrigin();

			VectorScale( dist, 1.0 / flInterval, dist );

			SetLocalVelocity( dist );
			return true;
		}
	}
	return false;
}

//-----------------------------------------------------------------------------
// Purpose: return max 1/10 second rate of turning
// Input  :
// Output :
//-----------------------------------------------------------------------------

float CAI_BaseNPC::MaxYawSpeed( void )
{
	return 45;
}

//-----------------------------------------------------------------------------
// Returns the estimate in seconds before we reach our nav goal.
// -1 means we don't know / haven't calculated it yet.
//-----------------------------------------------------------------------------
float CAI_BaseNPC::GetTimeToNavGoal()
{
	float flDist = GetNavigator()->BuildAndGetPathDistToGoal();
	if ( flDist < 0 )
	{
		return -1.0f;
	}

	float flSpeed = GetIdealSpeed();

	// FIXME: needs to consider stopping time!
	if (flSpeed > 0 && flDist > 0)
	{
		return flDist / flSpeed;
	}
	return 0.0;
}

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