/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */


#include <AzCore/Serialization/SerializeContext.h>

#include "AnimScreenFaderNode.h"
#include "ScreenFaderTrack.h"
#include <IRenderer.h>
#include "Maestro/Types/AnimNodeType.h"
#include "Maestro/Types/AnimValueType.h"
#include "Maestro/Types/AnimParamType.h"


//-----------------------------------------------------------------------------
namespace
{
    bool s_screenFaderNodeParamsInitialized = false;
    StaticInstance<std::vector<CAnimNode::SParamInfo>> s_screenFaderNodeParams;

    void AddSupportedParams(const char* sName, AnimParamType paramId, AnimValueType valueType)
    {
        CAnimNode::SParamInfo param;
        param.name = sName;
        param.paramType = paramId;
        param.valueType = valueType;
        param.flags = IAnimNode::eSupportedParamFlags_MultipleTracks;
        s_screenFaderNodeParams.push_back(param);
    }
};

//-----------------------------------------------------------------------------
bool CalculateIsolatedKeyColor(const IScreenFaderKey& key, float fTime, Vec4& colorOut)
{
    float ratio = fTime - key.time;

    if (ratio < 0.f)
    {
        return false;
    }

    if (key.m_fadeTime == 0.f)
    {
        colorOut(key.m_fadeColor.GetR(), key.m_fadeColor.GetG(), key.m_fadeColor.GetB(), key.m_fadeColor.GetA());
        if (key.m_fadeType == IScreenFaderKey::eFT_FadeIn)
        {
            colorOut.w = 0.f;
        }
        else
        {
            colorOut.w = 1.f;
        }
    }
    else
    {
        colorOut(key.m_fadeColor.GetR(), key.m_fadeColor.GetG(), key.m_fadeColor.GetB(), key.m_fadeColor.GetA());
        ratio = ratio / key.m_fadeTime;
        if (key.m_fadeType == IScreenFaderKey::eFT_FadeIn)
        {
            colorOut.w = MAX(0.f, 1.f - ratio);
        }
        else
        {
            colorOut.w = MIN(1.f, ratio);
        }
    }

    return true;
}

//-----------------------------------------------------------------------------
CAnimScreenFaderNode::CAnimScreenFaderNode(const int id)
    : CAnimNode(id, AnimNodeType::ScreenFader)
    , m_bActive(false)
    , m_screenWidth(800.f)
    , m_screenHeight(600.f)
    , m_lastActivatedKey(-1)
    , m_texPrecached(false)
{
    m_startColor = Vec4(1, 1, 1, 1);
    CAnimScreenFaderNode::Initialize();
    PrecacheTexData();
}

CAnimScreenFaderNode::CAnimScreenFaderNode()
    : CAnimScreenFaderNode(0)
{
}

CAnimScreenFaderNode::~CAnimScreenFaderNode()
{
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::Initialize()
{
    if (!s_screenFaderNodeParamsInitialized)
    {
        s_screenFaderNodeParamsInitialized = true;
        s_screenFaderNodeParams.reserve(1);
        AddSupportedParams("Fader", AnimParamType::ScreenFader, AnimValueType::Unknown);
    }
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::Animate(SAnimContext& ac)
{
    size_t const nScreenFaderTracksNumber = m_tracks.size();

    for (size_t nFaderTrackNo = 0; nFaderTrackNo < nScreenFaderTracksNumber; ++nFaderTrackNo)
    {
        CScreenFaderTrack* pTrack = static_cast<CScreenFaderTrack*>(GetTrackForParameter(AnimParamType::ScreenFader, static_cast<uint32>(nFaderTrackNo)));

        if (!pTrack)
        {
            continue;
        }

        if (pTrack->GetNumKeys() == 0)
        {
            continue;
        }

        if (pTrack->GetFlags() & IAnimTrack::eAnimTrackFlags_Disabled)
        {
            continue;
        }

        if (pTrack->IsMasked(ac.trackMask))
        {
            continue;
        }

        if (ac.singleFrame)
        {
            m_lastActivatedKey = -1;
        }

        IScreenFaderKey key;
        int nActiveKeyIndex = pTrack->GetActiveKey(ac.time, &key);

        if (nActiveKeyIndex >= 0)
        {
            if (m_lastActivatedKey != nActiveKeyIndex)
            {
                m_lastActivatedKey = nActiveKeyIndex;
                m_bActive = true;

                if (!key.m_strTexture.empty())
                {
                    if (pTrack->SetActiveTexture(nActiveKeyIndex))
                    {
                        pTrack->SetTextureVisible(true);
                    }
                    else
                    {
                        pTrack->SetTextureVisible(false);
                    }
                }
                else
                {
                    pTrack->SetTextureVisible(false);
                }
            }

            if (m_bActive || key.m_fadeTime + key.time > ac.time)
            {
                float ratio = (key.m_fadeTime > 0) ? (ac.time - key.time) / key.m_fadeTime : 1.f;
                if (ratio < 0.f)
                {
                    ratio = 0.f;
                }
                ratio = MIN(ratio, 1.f);

                switch (key.m_fadeChangeType)
                {
                case IScreenFaderKey::eFCT_Square:
                    ratio = ratio * ratio;
                    break;

                case  IScreenFaderKey::eFCT_CubicSquare:
                    ratio = ratio * ratio * ratio;
                    break;

                case IScreenFaderKey::eFCT_SquareRoot:
                    ratio = sqrt(ratio);
                    break;

                case IScreenFaderKey::eFCT_Sin:
                    ratio = sinf(ratio * 3.14159265f * 0.5f);
                    break;
                }

                if (!key.m_bUseCurColor || nActiveKeyIndex == 0)
                {
                    m_startColor(key.m_fadeColor.GetR(), key.m_fadeColor.GetG(), key.m_fadeColor.GetB(), key.m_fadeColor.GetA());
                }
                else
                {
                    IScreenFaderKey preKey;
                    pTrack->GetKey(nActiveKeyIndex - 1, &preKey);
                    CalculateIsolatedKeyColor(preKey, ac.time, m_startColor);
                }

                if (key.m_fadeType == IScreenFaderKey::eFT_FadeIn)
                {
                    if (!key.m_bUseCurColor || nActiveKeyIndex == 0)
                    {
                        m_startColor.w = 1.f;
                    }
                    key.m_fadeColor.SetA(0.f);
                }
                else
                {
                    if (!key.m_bUseCurColor || nActiveKeyIndex == 0)
                    {
                        m_startColor.w = 0.f;
                    }
                    key.m_fadeColor.SetA(1.f);
                }

                Vec4 fadeColorAsVec4(key.m_fadeColor.GetR(), key.m_fadeColor.GetG(), key.m_fadeColor.GetB(), key.m_fadeColor.GetA());
                pTrack->SetDrawColor(m_startColor + (fadeColorAsVec4 - m_startColor) * ratio);

                if (pTrack->GetDrawColor().w < 0.01f)
                {
                    m_bActive = IsAnyTextureVisible();
                }
                else
                {
                    m_bActive = true;
                }
            }
        }
        else
        {
            pTrack->SetTextureVisible(false);
            m_bActive = IsAnyTextureVisible();
        }
    }
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::CreateDefaultTracks()
{
    CreateTrack(AnimParamType::ScreenFader);
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::OnReset()
{
    CAnimNode::OnReset();
    m_bActive = false;
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::Activate(bool bActivate)
{
    if (bActivate)
    {
        m_bActive = false;
    }

    if (m_texPrecached == false)
    {
        PrecacheTexData();
    }
}

//-----------------------------------------------------------------------------
/// @deprecated Serialization for Sequence data in Component Entity Sequences now occurs through AZ::SerializeContext and the Sequence Component
void CAnimScreenFaderNode::Serialize
    (XmlNodeRef& xmlNode, bool bLoading, bool bLoadEmptyTracks)
{
    CAnimNode::Serialize(xmlNode, bLoading, bLoadEmptyTracks);

    if (bLoading)
    {
        PrecacheTexData();
    }
}

//////////////////////////////////////////////////////////////////////////
void CAnimScreenFaderNode::Reflect(AZ::ReflectContext* context)
{
    if (auto serializeContext = azrtti_cast<AZ::SerializeContext*>(context))
    {
        serializeContext->Class<CAnimScreenFaderNode, CAnimNode>()
            ->Version(1);
    }
}

//-----------------------------------------------------------------------------
unsigned int CAnimScreenFaderNode::GetParamCount() const
{
    return static_cast<unsigned int>(s_screenFaderNodeParams.size());
}

//-----------------------------------------------------------------------------
CAnimParamType CAnimScreenFaderNode::GetParamType(unsigned int nIndex) const
{
    if (nIndex < s_screenFaderNodeParams.size())
    {
        return s_screenFaderNodeParams[nIndex].paramType;
    }
    return AnimParamType::Invalid;
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::SetFlags(int flags)
{
    // call base class implementation. I'm avoiding the use of the Microsoft specific __super::SetFlags(flags) because it is not
    // platform agnostic
    CAnimNode::SetFlags(flags);

    if (flags & eAnimNodeFlags_Disabled)
    {
        // for screen faders, when disabling, we want to reset so the screen doesn't stay partially faded if a fade was in
        // effect when disabled
        OnReset();
    }
}

//-----------------------------------------------------------------------------
bool CAnimScreenFaderNode::GetParamInfoFromType(const CAnimParamType& paramId, SParamInfo& info) const
{
    for (size_t i = 0; i < s_screenFaderNodeParams.size(); ++i)
    {
        if (s_screenFaderNodeParams[i].paramType == paramId)
        {
            info = s_screenFaderNodeParams[i];
            return true;
        }
    }
    return false;
}

//-----------------------------------------------------------------------------
void CAnimScreenFaderNode::Render()
{
}

bool CAnimScreenFaderNode::IsAnyTextureVisible() const
{
    size_t const paramCount = m_tracks.size();
    for (size_t paramIndex = 0; paramIndex < paramCount; ++paramIndex)
    {
        CScreenFaderTrack* pTrack = static_cast<CScreenFaderTrack*>(GetTrackForParameter(AnimParamType::ScreenFader, static_cast<uint32>(paramIndex)));

        if (!pTrack)
        {
            continue;
        }

        if (pTrack->IsTextureVisible())
        {
            return true;
        }
    }

    return false;
}

void CAnimScreenFaderNode::PrecacheTexData()
{
    size_t const paramCount = m_tracks.size();
    for (size_t paramIndex = 0; paramIndex < paramCount; ++paramIndex)
    {
        IAnimTrack* pTrack = m_tracks[paramIndex].get();

        if (!pTrack)
        {
            continue;
        }

        switch (m_tracks[paramIndex]->GetParameterType().GetType())
        {
        case AnimParamType::ScreenFader:
        {
            CScreenFaderTrack* pFaderTrack = static_cast<CScreenFaderTrack*>(pTrack);
            pFaderTrack->PreloadTextures();
        }
        break;
        }
    }
    m_texPrecached = true;
}