//
//  ParticleSystemCurves.cpp
//  cocos2d_libs
//
//  Created by 徐俊杰 on 2020/4/24.
//

#include "rparticle/ParticleSystemCurves.h"

//#include "UnityPrefix.h"
#include "rparticle/ParticleSystemCurves.h"
#include "rparticle/Math/Polynomials.h"
//#include "Runtime/Math/Vector2.h"
//#include "Runtime/BaseClasses/ObjectDefines.h"
#include "rparticle/Serialize/TransferFunctions/SerializeTransfer.h"

NS_RRP_BEGIN

// Calculates the min max range of an animation curve analytically
static void CalculateCurveRangesValue(Vector2f& minMaxValue, const AnimationCurve& curve)
{
    const int keyCount = curve.GetKeyCount();
    if (keyCount == 0)
        return;
    
    if (keyCount == 1)
    {
        CalculateMinMax(minMaxValue, curve.GetKey(0).value);
    }
    else
    {
        int segmentCount = keyCount - 1;
        CalculateMinMax(minMaxValue, curve.GetKey(0).value);
        for (int i = 0;i<segmentCount;i++)
        {
            DebugAssert(i+1 < keyCount);
            AnimationCurve::Cache cache;
            curve.CalculateCacheData(cache, i, i + 1, 0.0F);
            
            // Differentiate polynomial
            float a = 3.0f * cache.coeff[0];
            float b = 2.0f * cache.coeff[1];
            float c = 1.0f * cache.coeff[2];
            
            const float start = curve.GetKey(i).time;
            const float end = curve.GetKey(i+1).time;
            
            float roots[2];
            int numRoots = QuadraticPolynomialRootsGeneric(a, b, c, roots[0], roots[1]);
            for(int r = 0; r < numRoots; r++)
                if((roots[r] >= 0.0f) && ((roots[r] + start) < end))
                    CalculateMinMax(minMaxValue, Polynomial::EvalSegment(roots[r], cache.coeff));
            CalculateMinMax(minMaxValue, Polynomial::EvalSegment(end-start, cache.coeff));
        }
    }
}

bool BuildCurves (MinMaxOptimizedPolyCurves& polyCurves, const MinMaxAnimationCurves& editorCurves, float scalar, short minMaxState)
{
    bool isOptimizedCurve = polyCurves.max.BuildOptimizedCurve(editorCurves.max, scalar);
    if ((minMaxState != kMMCTwoCurves) && (minMaxState != kMMCTwoConstants))
        isOptimizedCurve = isOptimizedCurve && polyCurves.min.BuildOptimizedCurve(editorCurves.max, scalar);
    else
        isOptimizedCurve = isOptimizedCurve && polyCurves.min.BuildOptimizedCurve(editorCurves.min, scalar);
    return isOptimizedCurve;
}

void BuildCurves (MinMaxPolyCurves& polyCurves, const MinMaxAnimationCurves& editorCurves, float scalar, short minMaxState)
{
    polyCurves.max.BuildCurve(editorCurves.max, scalar);
    if ((minMaxState != kMMCTwoCurves) && (minMaxState != kMMCTwoConstants))
        polyCurves.min.BuildCurve(editorCurves.max, scalar);
    else
        polyCurves.min.BuildCurve(editorCurves.min, scalar);
}

bool CurvesSupportProcedural (const MinMaxAnimationCurves& editorCurves, short minMaxState)
{
    bool isValid = PolynomialCurve::IsValidCurve(editorCurves.max);
    if ((minMaxState != kMMCTwoCurves) && (minMaxState != kMMCTwoConstants))
        return isValid;
    else
        return isValid && PolynomialCurve::IsValidCurve(editorCurves.min);
}


void MinMaxOptimizedPolyCurves::Integrate ()
{
    max.Integrate ();
    min.Integrate ();
}

void MinMaxOptimizedPolyCurves::DoubleIntegrate ()
{
    max.DoubleIntegrate ();
    min.DoubleIntegrate ();
}

Vector2f MinMaxOptimizedPolyCurves::FindMinMaxIntegrated()
{
    Vector2f minRange = min.FindMinMaxIntegrated();
    Vector2f maxRange = max.FindMinMaxIntegrated();
    Vector2f result = Vector2f(std::min(minRange.x, maxRange.x), std::max(minRange.y, maxRange.y));
    return result;
}

Vector2f MinMaxOptimizedPolyCurves::FindMinMaxDoubleIntegrated()
{
    Vector2f minRange = min.FindMinMaxDoubleIntegrated();
    Vector2f maxRange = max.FindMinMaxDoubleIntegrated();
    Vector2f result = Vector2f(std::min(minRange.x, maxRange.x), std::max(minRange.y, maxRange.y));
    return result;
}

void MinMaxPolyCurves::Integrate ()
{
    max.Integrate ();
    min.Integrate ();
}

void MinMaxPolyCurves::DoubleIntegrate ()
{
    max.DoubleIntegrate ();
    min.DoubleIntegrate ();
}

Vector2f MinMaxPolyCurves::FindMinMaxIntegrated()
{
    Vector2f minRange = min.FindMinMaxIntegrated();
    Vector2f maxRange = max.FindMinMaxIntegrated();
    Vector2f result = Vector2f(std::min(minRange.x, maxRange.x), std::max(minRange.y, maxRange.y));
    return result;
}

Vector2f MinMaxPolyCurves::FindMinMaxDoubleIntegrated()
{
    Vector2f minRange = min.FindMinMaxDoubleIntegrated();
    Vector2f maxRange = max.FindMinMaxDoubleIntegrated();
    Vector2f result = Vector2f(std::min(minRange.x, maxRange.x), std::max(minRange.y, maxRange.y));
    return result;
}

MinMaxCurve::MinMaxCurve ()
:    scalar (1.0f)
,    minMaxState (kMMCScalar)
,    isOptimizedCurve(false)
{
    SetPolynomialCurveToValue (editorCurves.max, polyCurves.max, 1.0f);
    SetPolynomialCurveToValue (editorCurves.min, polyCurves.min, 0.0f);
}

Vector2f MinMaxCurve::FindMinMax() const
{
    Vector2f result = Vector2f(std::numeric_limits<float>::infinity (), -std::numeric_limits<float>::infinity ());
    CalculateCurveRangesValue(result, editorCurves.max);
    if((minMaxState == kMMCTwoCurves) || (minMaxState == kMMCTwoConstants))
        CalculateCurveRangesValue(result, editorCurves.min);
    return result * GetScalar();
}

Vector2f MinMaxCurve::FindMinMaxIntegrated() const
{
    if(IsOptimized())
    {
        MinMaxOptimizedPolyCurves integrated = polyCurves;
        integrated.Integrate();
        return integrated.FindMinMaxIntegrated();
    }
    else
    {
        DebugAssert(CurvesSupportProcedural (editorCurves, minMaxState));
        MinMaxPolyCurves integrated;
        BuildCurves(integrated, editorCurves, GetScalar(), minMaxState);
        integrated.Integrate();
        return integrated.FindMinMaxIntegrated();
    }
}

Vector2f MinMaxCurve::FindMinMaxDoubleIntegrated() const
{
    if(IsOptimized())
    {
        MinMaxOptimizedPolyCurves doubleIntegrated = polyCurves;
        doubleIntegrated.DoubleIntegrate();
        return doubleIntegrated.FindMinMaxDoubleIntegrated();
    }
    else
    {
        DebugAssert(CurvesSupportProcedural (editorCurves, minMaxState));
        MinMaxPolyCurves doubleIntegrated;
        BuildCurves(doubleIntegrated, editorCurves, GetScalar(), minMaxState);
        doubleIntegrated.DoubleIntegrate();
        return doubleIntegrated.FindMinMaxDoubleIntegrated();
    }
}

template<class TransferFunction>
void MinMaxCurve::Transfer (TransferFunction& transfer)
{
    transfer.Transfer (scalar, "scalar");
    transfer.Transfer (editorCurves.max, "maxCurve");
    transfer.Transfer (editorCurves.min, "minCurve");
    TRANSFER (minMaxState); transfer.Align ();
    if (transfer.IsReading ())
        isOptimizedCurve = BuildCurves(polyCurves, editorCurves, scalar, minMaxState);
}
INSTANTIATE_TEMPLATE_TRANSFER(MinMaxCurve)

NS_RRP_END