/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011  Cyan Worlds, 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 3 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, see <http://www.gnu.org/licenses/>.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/
#ifndef plParticleGenerator_inc
#define plParticleGenerator_inc

#include "hsGeometry3.h"
#include "pnNetCommon/plSynchedValue.h"
class plParticleEmitter;
class plScalarController;

// This class is responsible for all the details of automatically generating particles for a plParticleEmitter.
// It gets a change in time, and must do whatever necessary to generate the appropriate number of particles
// for that timespan

class plParticleGenerator : public plCreatable
{

public:
    // returns false if it's done generating particles and is safe to delete.
    virtual hsBool AddAutoParticles(plParticleEmitter *emitter, float dt, UInt32 numForced = 0) = 0;

    virtual void UpdateParam(UInt32 paramID, hsScalar paramValue) = 0;

    CLASSNAME_REGISTER( plParticleGenerator );
    GETINTERFACE_ANY( plParticleGenerator, plCreatable );

    static const void ComputeDirection(float pitch, float yaw, hsVector3 &direction);
    static const void ComputePitchYaw(float &pitch, float &yaw, const hsVector3 &dir);
    static inline float GetRandomVar() { return 2.0f * (float)hsRand() / RAND_MAX - 1; } // returns a num between +/- 1.0
};

class plSimpleParticleGenerator : public plParticleGenerator
{
public:
    plSimpleParticleGenerator();
    ~plSimpleParticleGenerator();
    void Init(hsScalar genLife, hsScalar partLifeMin, hsScalar partLifeMax, hsScalar particlesPerSecond, 
              UInt32 numSources, hsPoint3 *pos, hsScalar *initPitch, hsScalar *initYaw, hsScalar angleRange,
              hsScalar initVelMin, hsScalar initVelMax, hsScalar xSize, hsScalar ySize, 
              hsScalar scaleMin, hsScalar scaleMax,
              hsScalar massRange, hsScalar radsPerSecRange);

    CLASSNAME_REGISTER( plSimpleParticleGenerator );
    GETINTERFACE_ANY( plSimpleParticleGenerator, plParticleGenerator);
    
    virtual hsBool AddAutoParticles(plParticleEmitter *emitter, float dt, UInt32 numForced);
    virtual void UpdateParam(UInt32 paramID, hsScalar paramValue);

    virtual void Read(hsStream* s, hsResMgr *mgr); 
    virtual void Write(hsStream* s, hsResMgr *mgr);

protected:
    hsScalar fParticlesPerSecond;
    UInt32 fNumSources;
    hsPoint3 *fInitPos;
    hsScalar *fInitPitch, *fInitYaw;
    hsScalar fAngleRange;
    hsScalar fVelMin, fVelMax;
    hsScalar fXSize, fYSize, fScaleMin, fScaleMax;
    hsScalar fGenLife;  // How long shall we spit out particles from this location? When this time runs out, we stop
                        // spitting particles, but we don't actually die until all of our particles die naturally.
                        // (Even the ones that we feel are suffering needlessly.)

    hsScalar fPartLifeMin; // lifespan for the particles we generate
    hsScalar fPartLifeMax;

    hsScalar fPartInvMassMin;   // Doing a uniform variant over the inverse mass range (instead of over the mass range
    hsScalar fPartInvMassRange; // and then inverting) will favor the low end of the mass range, but then again,
                                // it's just a freaking game. Note though that fPartInvMassMin == 1.f / massMAX.

    hsScalar fPartRadsPerSecRange; // Zero means no rot, otherwise uniform random between [-range..range]

    hsScalar fParticleSum;

    enum
    {
        kImmortal   = 0x1,
        kDisabled   = 0x2,
    };
    UInt32 fMiscFlags;
};

class plOneTimeParticleGenerator : public plParticleGenerator
{
public:

    plOneTimeParticleGenerator();
    ~plOneTimeParticleGenerator();
    void Init(hsScalar count, hsPoint3 *pointArray, hsVector3 *dirArray, 
              hsScalar xSize, hsScalar ySize, hsScalar scaleMin, hsScalar scaleMax, hsScalar radsPerSec);

    CLASSNAME_REGISTER( plOneTimeParticleGenerator );
    GETINTERFACE_ANY( plOneTimeParticleGenerator, plParticleGenerator);

    virtual hsBool AddAutoParticles(plParticleEmitter *emitter, float dt, UInt32 numForced = 0);
    virtual void UpdateParam(UInt32 paramID, hsScalar paramValue) {}

    virtual void Read(hsStream* s, hsResMgr *mgr); 
    virtual void Write(hsStream* s, hsResMgr *mgr);

protected:
    hsScalar fCount;
    hsPoint3 *fPosition;
    hsVector3 *fDirection;
    hsScalar fXSize, fYSize, fScaleMin, fScaleMax;
    hsScalar fPartRadsPerSecRange; // Zero means no rot, otherwise uniform random between [-range..range]
};

#endif