#include "CWorldShadow.hpp"
#include "CWorld.hpp"
#include "CStateManager.hpp"
#include "Graphics/CBooRenderer.hpp"

namespace urde
{

CWorldShadow::CWorldShadow(u32 w, u32 h, bool rgba8)
: m_shader(w, h) {}

void CWorldShadow::EnableModelProjectedShadow(const zeus::CTransform& pos, s32 lightIdx, float f1)
{
    zeus::CTransform texTransform = zeus::lookAt(zeus::CVector3f::skZero, x74_lightPos - x68_objPos);
    zeus::CTransform posXf = pos;
    posXf.origin = zeus::CVector3f::skZero;
    texTransform = posXf.inverse() * texTransform;
    texTransform = (texTransform * zeus::CTransform::Scale(float(M_SQRT2) * x64_objHalfExtent * f1)).inverse();
    texTransform = zeus::CTransform::Translate(0.5f, 0.f, 0.5f) * texTransform;
    CBooModel::EnableShadowMaps(m_shader.GetTexture(), texTransform);
}

void CWorldShadow::DisableModelProjectedShadow()
{
    CBooModel::DisableShadowMaps();
}

void CWorldShadow::BuildLightShadowTexture(const CStateManager& mgr, TAreaId aid, s32 lightIdx,
                                           const zeus::CAABox& aabb, bool motionBlur, bool lighten)
{
    if (x80_aid != aid || x84_lightIdx != lightIdx)
    {
        x88_blurReset = true;
        x80_aid = aid;
        x84_lightIdx = lightIdx;
    }

    if (aid != kInvalidAreaId)
    {
        const CGameArea* area = mgr.GetWorld()->GetAreaAlways(aid);
        if (area->IsPostConstructed())
        {
            const CWorldLight& light = area->GetPostConstructed()->x60_lightsA[lightIdx];
            zeus::CVector3f centerPoint = aabb.center();
            if (const CPVSAreaSet* pvs = area->GetAreaVisSet())
            {
                CPVSVisSet lightSet = pvs->Get1stLightSet(lightIdx);
                g_Renderer->EnablePVS(lightSet, aid);
            }
            else
            {
                CPVSVisSet visSet;
                visSet.Reset(EPVSVisSetState::OutOfBounds);
                g_Renderer->EnablePVS(visSet, aid);
            }
            zeus::CVector3f lightToPoint = centerPoint - light.GetPosition();
            x64_objHalfExtent = (aabb.max - centerPoint).magnitude();
            float distance = lightToPoint.magnitude();
            float fov = zeus::radToDeg(std::atan2(x64_objHalfExtent, distance)) * 2.f;
            if (fov >= 0.00001f)
            {
                lightToPoint.normalize();
                x4_view = zeus::lookAt(light.GetPosition(), centerPoint, zeus::CVector3f::skDown);
                x68_objPos = centerPoint;
                x74_lightPos = light.GetPosition();
                CGraphics::SetViewPointMatrix(x4_view);
                zeus::CFrustum frustum;
                frustum.updatePlanes(x4_view, zeus::SProjPersp(
                    zeus::degToRad(fov), 1.f, 0.1f, distance + x64_objHalfExtent));
                g_Renderer->SetClippingPlanes(frustum);
                g_Renderer->SetPerspective(fov, m_shader.GetWidth(), m_shader.GetHeight(), 0.1f, 1000.f);
                SViewport backupVp = g_Viewport;
                zeus::CVector2f backupDepthRange = CGraphics::g_CachedDepthRange;
                m_shader.bindRenderTarget();
                g_Renderer->SetViewport(0, 0, m_shader.GetWidth(), m_shader.GetHeight());
                CGraphics::SetDepthRange(0.f, 1.f);

                x34_model = zeus::lookAt(centerPoint - zeus::CVector3f(0.f, 0.f, 0.1f), light.GetPosition());
                CGraphics::SetModelMatrix(x34_model);

                m_shadowViewProj = CGraphics::GetPerspectiveProjectionMatrix(false) *
                                   CGraphics::g_CameraMatrix.toMatrix4f();

                float extent = float(M_SQRT2) * x64_objHalfExtent;
                /* Depth test and write */
                /* Color white 100% alpha */
                m_shader.drawBase(extent);

                CGraphics::SetModelMatrix(zeus::CTransform::Identity());
                CBooModel::SetDrawingOccluders(true);
                g_Renderer->PrepareDynamicLights({});
                g_Renderer->DrawUnsortedGeometry(aid, 0, 0);
                CBooModel::SetDrawingOccluders(false);

                if (lighten)
                {
                    CGraphics::SetModelMatrix(x34_model);
                    /* No depth test or write */
                    /* Color white 25% alpha */
                    m_shader.lightenShadow();
                }

                if (motionBlur && !x88_blurReset)
                {
                    /* No depth test or write */
                    /* Color white 85% alpha */
                    /* Draw in shadow texture */
                    m_shader.blendPreviousShadow();
                }

                x88_blurReset = false;

                m_shader.resolveTexture();
                CBooRenderer::BindMainDrawTarget();

                g_Renderer->SetViewport(backupVp.x0_left, backupVp.x4_top, backupVp.x8_width, backupVp.xc_height);
                CGraphics::SetDepthRange(backupDepthRange[0], backupDepthRange[1]);
            }
        }
    }
}

void CWorldShadow::ResetBlur()
{
    x88_blurReset = true;
}

}