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

#include "cbase.h"
#include "basegrenade_shared.h"
#include "grenade_frag.h"
#include "Sprite.h"
#include "SpriteTrail.h"
#include "soundent.h"

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

#define FRAG_GRENADE_BLIP_FREQUENCY			1.0f
#define FRAG_GRENADE_BLIP_FAST_FREQUENCY	0.3f

#define FRAG_GRENADE_GRACE_TIME_AFTER_PICKUP 1.5f

const float GRENADE_COEFFICIENT_OF_RESTITUTION = 0.2f;

ConVar sk_plr_dmg_fraggrenade	( "sk_plr_dmg_fraggrenade","0");
ConVar sk_npc_dmg_fraggrenade	( "sk_npc_dmg_fraggrenade","0");
ConVar sk_fraggrenade_radius	( "sk_fraggrenade_radius", "0");

#define GRENADE_MODEL "models/Weapons/w_grenade.mdl"

class CGrenadeFrag : public CBaseGrenade
{
	DECLARE_CLASS( CGrenadeFrag, CBaseGrenade );

#if !defined( CLIENT_DLL )
	DECLARE_DATADESC();
#endif
					
	~CGrenadeFrag( void );

public:
	void	Spawn( void );
	void	OnRestore( void );
	void	Precache( void );
	bool	CreateVPhysics( void );
	void	CreateEffects( void );
	void	SetTimer( float detonateDelay, float warnDelay );
	void	SetVelocity( const Vector &velocity, const AngularImpulse &angVelocity );
	int		OnTakeDamage( const CTakeDamageInfo &inputInfo );
	void	BlipSound() { EmitSound( "Grenade.Blip" ); }
	void	DelayThink();
	void	VPhysicsUpdate( IPhysicsObject *pPhysics );
	void	OnPhysGunPickup( CBasePlayer *pPhysGunUser, PhysGunPickup_t reason );

protected:
	CHandle<CSprite>		m_pMainGlow;
	CHandle<CSpriteTrail>	m_pGlowTrail;

	float	m_flNextBlipTime;
	bool	m_inSolid;
};

LINK_ENTITY_TO_CLASS( npc_grenade_frag, CGrenadeFrag );

BEGIN_DATADESC( CGrenadeFrag )

	// Fields
	DEFINE_FIELD( m_pMainGlow, FIELD_EHANDLE ),
	DEFINE_FIELD( m_pGlowTrail, FIELD_EHANDLE ),
	DEFINE_FIELD( m_flNextBlipTime, FIELD_TIME ),
	DEFINE_FIELD( m_inSolid, FIELD_BOOLEAN ),
	
	// Function Pointers
	DEFINE_THINKFUNC( DelayThink ),

END_DATADESC()


//-----------------------------------------------------------------------------
// Purpose: 
//-----------------------------------------------------------------------------
CGrenadeFrag::~CGrenadeFrag( void )
{
}

void CGrenadeFrag::Spawn( void )
{
	Precache( );

	SetModel( GRENADE_MODEL );

	if( GetOwnerEntity() && GetOwnerEntity()->IsPlayer() )
	{
		m_flDamage		= sk_plr_dmg_fraggrenade.GetFloat();
		m_DmgRadius		= sk_fraggrenade_radius.GetFloat();
	}
	else
	{
		m_flDamage		= sk_npc_dmg_fraggrenade.GetFloat();
		m_DmgRadius		= sk_fraggrenade_radius.GetFloat();
	}

	m_takedamage	= DAMAGE_YES;
	m_iHealth		= 1;

	SetSize( -Vector(4,4,4), Vector(4,4,4) );
	SetCollisionGroup( COLLISION_GROUP_WEAPON );
	CreateVPhysics();

	CreateEffects();

	BlipSound();
	m_flNextBlipTime = gpGlobals->curtime + FRAG_GRENADE_BLIP_FREQUENCY;

	AddSolidFlags( FSOLID_NOT_STANDABLE );

	BaseClass::Spawn();
}

//-----------------------------------------------------------------------------
// Purpose: 
//-----------------------------------------------------------------------------
void CGrenadeFrag::OnRestore( void )
{
	CreateEffects();

	BaseClass::OnRestore();
}

//-----------------------------------------------------------------------------
// Purpose: 
//-----------------------------------------------------------------------------
void CGrenadeFrag::CreateEffects( void )
{
	// Start up the eye glow
	m_pMainGlow = CSprite::SpriteCreate( "sprites/redglow1.vmt", GetLocalOrigin(), false );

	int	nAttachment = LookupAttachment( "fuse" );

	if ( m_pMainGlow != NULL )
	{
		m_pMainGlow->FollowEntity( this );
		m_pMainGlow->SetAttachment( this, nAttachment );
		m_pMainGlow->SetTransparency( kRenderGlow, 255, 255, 255, 200, kRenderFxNoDissipation );
		m_pMainGlow->SetScale( 0.2f );
		m_pMainGlow->SetGlowProxySize( 4.0f );
	}

	// Start up the eye trail
	m_pGlowTrail	= CSpriteTrail::SpriteTrailCreate( "sprites/bluelaser1.vmt", GetLocalOrigin(), false );

	if ( m_pGlowTrail != NULL )
	{
		m_pGlowTrail->FollowEntity( this );
		m_pGlowTrail->SetAttachment( this, nAttachment );
		m_pGlowTrail->SetTransparency( kRenderTransAdd, 255, 0, 0, 255, kRenderFxNone );
		m_pGlowTrail->SetStartWidth( 8.0f );
		m_pGlowTrail->SetEndWidth( 1.0f );
		m_pGlowTrail->SetLifeTime( 0.5f );
	}
}

bool CGrenadeFrag::CreateVPhysics()
{
	// Create the object in the physics system
	VPhysicsInitNormal( SOLID_BBOX, 0, false );
	return true;
}

// this will hit only things that are in newCollisionGroup, but NOT in collisionGroupAlreadyChecked
class CTraceFilterCollisionGroupDelta : public CTraceFilterEntitiesOnly
{
public:
	// It does have a base, but we'll never network anything below here..
	DECLARE_CLASS_NOBASE( CTraceFilterCollisionGroupDelta );
	
	CTraceFilterCollisionGroupDelta( const IHandleEntity *passentity, int collisionGroupAlreadyChecked, int newCollisionGroup )
		: m_pPassEnt(passentity), m_collisionGroupAlreadyChecked( collisionGroupAlreadyChecked ), m_newCollisionGroup( newCollisionGroup )
	{
	}
	
	virtual bool ShouldHitEntity( IHandleEntity *pHandleEntity, int contentsMask )
	{
		if ( !PassServerEntityFilter( pHandleEntity, m_pPassEnt ) )
			return false;
		CBaseEntity *pEntity = EntityFromEntityHandle( pHandleEntity );

		if ( pEntity )
		{
			if ( g_pGameRules->ShouldCollide( m_collisionGroupAlreadyChecked, pEntity->GetCollisionGroup() ) )
				return false;
			if ( g_pGameRules->ShouldCollide( m_newCollisionGroup, pEntity->GetCollisionGroup() ) )
				return true;
		}

		return false;
	}

protected:
	const IHandleEntity *m_pPassEnt;
	int		m_collisionGroupAlreadyChecked;
	int		m_newCollisionGroup;
};

void CGrenadeFrag::VPhysicsUpdate( IPhysicsObject *pPhysics )
{
	BaseClass::VPhysicsUpdate( pPhysics );
	Vector vel;
	AngularImpulse angVel;
	pPhysics->GetVelocity( &vel, &angVel );
	
	Vector start = GetAbsOrigin();
	// find all entities that my collision group wouldn't hit, but COLLISION_GROUP_NONE would and bounce off of them as a ray cast
	CTraceFilterCollisionGroupDelta filter( this, GetCollisionGroup(), COLLISION_GROUP_NONE );
	trace_t tr;

	// UNDONE: Hull won't work with hitboxes - hits outer hull.  But the whole point of this test is to hit hitboxes.
#if 0
	UTIL_TraceHull( start, start + vel * gpGlobals->frametime, CollisionProp()->OBBMins(), CollisionProp()->OBBMaxs(), CONTENTS_HITBOX|CONTENTS_MONSTER|CONTENTS_SOLID, &filter, &tr );
#else
	UTIL_TraceLine( start, start + vel * gpGlobals->frametime, CONTENTS_HITBOX|CONTENTS_MONSTER|CONTENTS_SOLID, &filter, &tr );
#endif
	if ( tr.startsolid )
	{
		if ( !m_inSolid )
		{
			// UNDONE: Do a better contact solution that uses relative velocity?
			vel *= -GRENADE_COEFFICIENT_OF_RESTITUTION; // bounce backwards
			pPhysics->SetVelocity( &vel, NULL );
		}
		m_inSolid = true;
		return;
	}
	m_inSolid = false;
	if ( tr.DidHit() )
	{
		Vector dir = vel;
		VectorNormalize(dir);
		// send a tiny amount of damage so the character will react to getting bonked
		CTakeDamageInfo info( this, GetThrower(), pPhysics->GetMass() * vel, GetAbsOrigin(), 0.1f, DMG_CRUSH );
		tr.m_pEnt->TakeDamage( info );

		// reflect velocity around normal
		vel = -2.0f * tr.plane.normal * DotProduct(vel,tr.plane.normal) + vel;
		
		// absorb 80% in impact
		vel *= GRENADE_COEFFICIENT_OF_RESTITUTION;
		angVel *= -0.5f;
		pPhysics->SetVelocity( &vel, &angVel );
	}
}


void CGrenadeFrag::Precache( void )
{
	PrecacheModel( GRENADE_MODEL );

	PrecacheScriptSound( "Grenade.Blip" );

	PrecacheModel( "sprites/redglow1.vmt" );
	PrecacheModel( "sprites/bluelaser1.vmt" );

	BaseClass::Precache();
}

void CGrenadeFrag::SetTimer( float detonateDelay, float warnDelay )
{
	m_flDetonateTime = gpGlobals->curtime + detonateDelay;
	m_flWarnAITime = gpGlobals->curtime + warnDelay;
	SetThink( &CGrenadeFrag::DelayThink );
	SetNextThink( gpGlobals->curtime );
}

void CGrenadeFrag::OnPhysGunPickup( CBasePlayer *pPhysGunUser, PhysGunPickup_t reason )
{
#ifdef HL2MP
	SetTimer( FRAG_GRENADE_GRACE_TIME_AFTER_PICKUP, FRAG_GRENADE_GRACE_TIME_AFTER_PICKUP / 2);
	SetThrower( pPhysGunUser );

	BlipSound();
	m_flNextBlipTime = gpGlobals->curtime + FRAG_GRENADE_BLIP_FAST_FREQUENCY;
	m_bHasWarnedAI = true;
#endif

	BaseClass::OnPhysGunPickup( pPhysGunUser, reason );
}

void CGrenadeFrag::DelayThink() 
{
	if( gpGlobals->curtime > m_flDetonateTime )
	{
		Detonate();
		return;
	}

	if( !m_bHasWarnedAI && gpGlobals->curtime >= m_flWarnAITime )
	{
#if !defined( CLIENT_DLL )
		CSoundEnt::InsertSound ( SOUND_DANGER, GetAbsOrigin(), 400, 1.5, this );
#endif
		m_bHasWarnedAI = true;
	}
	
	if( gpGlobals->curtime > m_flNextBlipTime )
	{
		BlipSound();
		
		if( m_bHasWarnedAI )
		{
			m_flNextBlipTime = gpGlobals->curtime + FRAG_GRENADE_BLIP_FAST_FREQUENCY;
		}
		else
		{
			m_flNextBlipTime = gpGlobals->curtime + FRAG_GRENADE_BLIP_FREQUENCY;
		}
	}

	SetNextThink( gpGlobals->curtime + 0.1 );
}

void CGrenadeFrag::SetVelocity( const Vector &velocity, const AngularImpulse &angVelocity )
{
	IPhysicsObject *pPhysicsObject = VPhysicsGetObject();
	if ( pPhysicsObject )
	{
		pPhysicsObject->AddVelocity( &velocity, &angVelocity );
	}
}

int CGrenadeFrag::OnTakeDamage( const CTakeDamageInfo &inputInfo )
{
	// Manually apply vphysics because BaseCombatCharacter takedamage doesn't call back to CBaseEntity OnTakeDamage
	VPhysicsTakeDamage( inputInfo );

	// Grenades only suffer blast damage and burn damage.
	if( !(inputInfo.GetDamageType() & (DMG_BLAST|DMG_BURN) ) )
		return 0;

	return BaseClass::OnTakeDamage( inputInfo );
}

CBaseGrenade *Fraggrenade_Create( const Vector &position, const QAngle &angles, const Vector &velocity, const AngularImpulse &angVelocity, CBaseEntity *pOwner, float timer )
{
	// Don't set the owner here, or the player can't interact with grenades he's thrown
	CGrenadeFrag *pGrenade = (CGrenadeFrag *)CBaseEntity::Create( "npc_grenade_frag", position, angles, pOwner );
	
	pGrenade->SetTimer( timer, timer - 1.5f );
	pGrenade->SetVelocity( velocity, angVelocity );
	pGrenade->SetThrower( ToBaseCombatCharacter( pOwner ) );
	pGrenade->m_takedamage = DAMAGE_EVENTS_ONLY;

	return pGrenade;
}

