#include "brush.h"
#include "baseentity.h"
#include "cglm/mat4.h"
#include "physics.h"
#include "rendering.h"
#include "tier0/platform.h"
#include "tier1/utlbuffer.h"
#include "tier1/utlvector.h"
#include "math3d.h"

CUtlVector<IVertexBuffer*> g_BrushVertices;

void CBrushEntity::Precache()
{

}

void CBrushEntity::Spawn()
{
	/* physics don't support unindexed meshes, so generate indicies */
	CUtlBuffer<uint32_t> indicies(m_mesh.GetSize()*3);
	for (uint32_t i = 0;i<indicies.GetSize();i++)
	{
		indicies[i]=i;
	}
	/* copy over the triangles to a separate buffer, which will be used by physics */
	CUtlBuffer<Point<float>> triangles(m_mesh.GetSize()*3);
	uint32_t i = 0;
	for (auto tri: m_mesh)
	{
		V_memcpy(&triangles[i],tri.location,36);
		i+=3;
	}
	/* use them */
	px_collider_params params = {};
	params.friction = 0.0;
	m_collider = px_trimesh((Point<float>*)triangles.GetMemory(), triangles.GetSize(), (uint32_t(*)[3])indicies.GetMemory(), indicies.GetSize()/3 ,params);
	px_fixedbody(px, m_collider);
};

void CBrushEntity::Destroy()
{

}
void CBrushEntity::Think( float fDelta )
{

};

void CBrushEntity::Sync( void *pData, uint32_t nDataSize )
{

};



void CBrushEntity::ReadParameter( const char *szName, const char *szValue )
{
	CBaseEntity::ReadParameter(szName, szValue);
};


void C_BrushEntity::Precache()
{
	CBrushEntity* pBrushEntity = dynamic_cast<CBrushEntity*>(pEntity);
	if (!pBrushEntity)
		Plat_FatalErrorFunc("pEntity is not a CBrushEntity");
}

void C_BrushEntity::Spawn()
{
	struct Vertex_t
	{
		float position[3];
		float uv[2];
	};

	CBrushEntity* pBrushEntity = (CBrushEntity*)pEntity;
	uint32_t numVertices = pBrushEntity->m_mesh.GetSize();
	
	vertexBuffer = IRenderer::CreateVertexBuffer(numVertices*60);

	Vertex_t *pTriangles = (Vertex_t*)vertexBuffer->Map();
	uint32_t i = 0;
	for (auto &triangle: pBrushEntity->m_mesh)
	{
		pTriangles[i].position[0] = triangle.location[0];
		pTriangles[i].position[1] = triangle.location[1];
		pTriangles[i].position[2] = triangle.location[2];
		pTriangles[i].uv[0] = triangle.uv[0];
		pTriangles[i].uv[1] = triangle.uv[1];
		pTriangles[i+1].position[0] = triangle.location[3];
		pTriangles[i+1].position[1] = triangle.location[4];
		pTriangles[i+1].position[2] = triangle.location[5];
		pTriangles[i+1].uv[0] = triangle.uv[2];
		pTriangles[i+1].uv[1] = triangle.uv[3];
		pTriangles[i+2].position[0] = triangle.location[6];
		pTriangles[i+2].position[1] = triangle.location[7];
		pTriangles[i+2].position[2] = triangle.location[8];
		pTriangles[i+2].uv[0] = triangle.uv[4];
		pTriangles[i+2].uv[1] = triangle.uv[5];
		i+=3;
	}
	vertexBuffer->Unmap();
};

void C_BrushEntity::Destroy()
{

}
void C_BrushEntity::Think( float fDelta )
{
	g_BrushVertices.AppendTail(vertexBuffer);
};
	

class CBrushRendering: public IRenderingPipelineStep
{
public:
	virtual void Init() override;
	virtual void Frame( float fDelta ) override;
	virtual void Deinit() override;
private:
};
DECLARE_MESH_RENDERING_STAGE(CBrushRendering, brush_rasterizer);


IGraphicsPipeline *g_BrushPipeline;
ITexture *bricks;
void CBrushRendering::Init()
{
	g_BrushPipeline = IRenderer::CreateGraphicsPipeline(
		{
		{"gfx/mesh_vert.shader", SHADER_TYPE_VERTEX},
		{"gfx/mesh_frag.shader", SHADER_TYPE_FRAGMENT},
		},
		{
			{SHADER_INPUT_TYPE_UNIFORM_BUFFER,0},
			{SHADER_INPUT_TYPE_TEXTURES,1},
		}, 
		80,
		20,
		{{0,0,EVertexFormat::VERTEX_FORMAT_X32Y32Z32}, {12,1,EVertexFormat::VERTEX_FORMAT_X32Y32}},
		{EImageFormat::IMAGE_FORMAT_R8G8B8A8},
		true
	);
	bricks = ITextureManager::LoadTexture("textures/bricks.png");
};

void CBrushRendering::Frame( float fDelta )
{
	IRenderer::ResetState();
	IRenderer::SetDepthMode(DEPTH_MODE_LESS);
	IRenderer::BindPipeline(g_BrushPipeline);
	struct {
		mat4 i;
		uint32_t a = ITextureManager::GetTextureID(bricks);
		uint32_t b = 0;
		uint32_t c = 0;
	} constants;
	glm_mat4_identity(constants.i);
	IRenderer::SetConstants(sizeof(constants), &constants);
	IRenderer::BindData(0, IRenderer::GetCameraMatrix(), 0);
	IRenderer::PushBindings();
	for (auto &v: g_BrushVertices)
	{
		IRenderer::Draw(v, 0);
	}
	g_BrushVertices = {};
};

void CBrushRendering::Deinit()
{

};