#include "CSimpleShadow.hpp"
#include "CStateManager.hpp"
#include "Collision/CGameCollision.hpp"

namespace urde
{

CSimpleShadow::CSimpleShadow(float scale, float userAlpha, float maxObjHeight, float displacement)
: x30_scale(scale), x38_userAlpha(userAlpha), x40_maxObjHeight(maxObjHeight), x44_displacement(displacement)
{
    x48_24_collision = false;
    x48_25_alwaysCalculateRadius = true;
    x48_26_radiusCalculated = false;
}

zeus::CAABox CSimpleShadow::GetMaxShadowBox(const zeus::CAABox& aabb) const
{
    float extent = x34_radius * x30_scale;
    zeus::CVector3f center = aabb.center();
    zeus::CAABox expandedAABB = aabb;
    expandedAABB.accumulateBounds({center.x + extent, center.y + extent, center.z - GetMaxObjectHeight()});
    expandedAABB.accumulateBounds({center.x - extent, center.y - extent, center.z - GetMaxObjectHeight()});
    return expandedAABB;
}

zeus::CAABox CSimpleShadow::GetBounds() const
{
    float extent = x34_radius * x30_scale;
    return {{x0_xf.origin.x - extent, x0_xf.origin.y - extent, x0_xf.origin.z - extent},
            {x0_xf.origin.x + extent, x0_xf.origin.y + extent, x0_xf.origin.z + extent}};
}

void CSimpleShadow::Render(const TLockedToken<CTexture>& tex) const
{
    if (!x48_24_collision)
        return;

    CGraphics::DisableAllLights();
    CGraphics::SetModelMatrix(x0_xf);

    if (!m_filter || m_filter->GetTex().GetObj() != tex.GetObj())
        m_filter.emplace(EFilterType::InvDstMultiply, tex, CTexturedQuadFilter::ZTest::LEqual);

    float radius = x34_radius * x30_scale;
    CTexturedQuadFilter::Vert verts[] =
    {
        {{-radius, 0.f, -radius}, {0.f, 0.f}},
        {{radius, 0.f, -radius}, {0.f, 1.f}},
        {{-radius, 0.f, radius}, {1.f, 0.f}},
        {{radius, 0.f, radius}, {1.f, 1.f}}
    };
    m_filter->drawVerts(zeus::CColor::skWhite, verts);
}

void CSimpleShadow::Calculate(const zeus::CAABox& aabb, const zeus::CTransform& xf, const CStateManager& mgr)
{
    x48_24_collision = false;
    float halfHeight = (aabb.max.z - aabb.min.z) * 0.5f;
    zeus::CVector3f pos = xf.origin + zeus::CVector3f(0.f, 0.f, halfHeight);
    CRayCastResult res = mgr.RayStaticIntersection(pos, zeus::CVector3f::skDown, x40_maxObjHeight,
                         CMaterialFilter::MakeExclude({EMaterialTypes::SeeThrough}));
    float height = x40_maxObjHeight;
    if (res.IsValid())
    {
        x48_24_collision = true;
        height = res.GetT();
    }

    if (height > 0.1f + halfHeight)
    {
        TUniqueId cid = kInvalidUniqueId;
        rstl::reserved_vector<TUniqueId, 1024> nearList;
        CRayCastResult resD = CGameCollision::RayDynamicIntersection(mgr, cid, pos,
                              zeus::CVector3f::skDown, x40_maxObjHeight,
                              CMaterialFilter::skPassEverything, nearList);
        if (resD.IsValid() && resD.GetT() < height)
        {
            x48_24_collision = true;
            height = resD.GetT();
            res = resD;
        }
    }

    if (x48_24_collision)
    {
        x3c_heightAlpha = 1.f - height / x40_maxObjHeight;
        x0_xf = zeus::lookAt(res.GetPlane().normal(), zeus::CVector3f::skZero);
        x0_xf.origin = res.GetPlane().normal() * x44_displacement + res.GetPoint();
        if (x48_25_alwaysCalculateRadius || !x48_26_radiusCalculated)
        {
            float xExtent = aabb.max.x - aabb.min.x;
            float yExtent = aabb.max.y - aabb.min.y;
            x34_radius = std::sqrt(xExtent * xExtent + yExtent * yExtent) * 0.5f;
            x48_26_radiusCalculated = true;
        }
    }
}

}