/*
r_context.c -- dx2 renderer context
Copyright (C) 2023-2024 a1batross
Copyright (C) 2025-2026 lewa_j

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
*/

#define INITGUID
#include "r_local.h"
#include "xash3d_mathlib.h"
#include "crtlib.h"
#include "r_studioint.h"

//#pragma comment(lib, "ddraw.lib")
//TODO COM_GetProcAddress


static void R_SimpleStub( void )
{
	;
}

static void R_SimpleStubInt( int unused )
{
	;
}

static void R_SimpleStubUInt( unsigned int unused )
{
	;
}

static const char *R_GetConfigName( void )
{
	return "ref_dx2";
}

static qboolean R_SetDisplayTransform( ref_screen_rotation_t rotate, int offset_x, int offset_y, float scale_x, float scale_y )
{
	qboolean ret = true;

	tr.rotation = rotate;

	if( offset_x || offset_y )
	{
		gEngfuncs.Con_Printf("offset transform not supported\n");
		ret = false;
	}

	if( scale_x != 1.0f || scale_y != 1.0f )
	{
		gEngfuncs.Con_Printf("scale transform not supported\n");
		ret = false;
	}

	return ret;
}

void GL_BackendStartFrame( void )
{

}

void GL_BackendEndFrame( void )
{

}

void GL_SetRenderMode( int mode )
{
	dxc.renderMode = mode;
}


static void R_ProcessEntData( qboolean allocate, cl_entity_t *entities, unsigned int max_entities )
{
	if (!allocate)
	{
		tr.draw_list->num_solid_entities = 0;
		tr.draw_list->num_trans_entities = 0;
		tr.draw_list->num_beam_entities = 0;

		tr.max_entities = 0;
		tr.entities = NULL;
	}
	else
	{
		tr.max_entities = max_entities;
		tr.entities = entities;
	}

	if (gEngfuncs.drawFuncs->R_ProcessEntData)
		gEngfuncs.drawFuncs->R_ProcessEntData(allocate);
}

static void R_SetupSky( int *skytextures )
{
	;
}

static qboolean VID_ScreenShot( const char *filename, int shot_type )
{
	return false;
}

static qboolean VID_CubemapShot( const char *base, uint size, const float *vieworg, qboolean skyshot )
{
	return false;
}

static colorVec R_LightPoint( const float *p )
{
	colorVec c = { 0 };
	return c;
}

static void R_DecalShoot( int textureIndex, int entityIndex, int modelIndex, vec3_t pos, int flags, float scale )
{
	;
}

static int R_CreateDecalList( struct decallist_s *pList )
{
	return 0;
}

static float R_StudioEstimateFrame( cl_entity_t *e, mstudioseqdesc_t *pseqdesc, double time )
{
	return 0.0f;
}

static void R_StudioLerpMovement( cl_entity_t *e, double time, vec3_t origin, vec3_t angles )
{
	;
}

static qboolean R_StudioFillAPI( struct engine_studio_api_s *api, struct r_studio_interface_s *pDefaultDraw )
{
	return false;
}

static r_studio_interface_t *pStudioDraw;

static void R_StudioSetDrawInterface( struct r_studio_interface_s *pDraw )
{
	pStudioDraw = pDraw;
}

static void R_SetSkyCloudsTextures( int solidskyTexture, int alphaskyTexture )
{
	;
}

static void CL_RunLightStyles( lightstyle_t *ls )
{

}

static qboolean Mod_ProcessRenderData( model_t *mod, qboolean create, const byte *buffer, size_t buffersize )
{
	gEngfuncs.Con_Printf("Mod_ProcessRenderData(%p(%s), %d, %p, %zu)\n", mod, mod->name, create, buffer, buffersize);
	return true;
}

static void Mod_StudioLoadTextures( model_t *mod, void *data )
{
	;
}

static void CL_DrawParticles( double frametime, particle_t *particles, float partsize )
{
	;
}

static void CL_DrawTracers( double frametime, particle_t *tracers )
{
	;
}

static void CL_DrawBeams( int fTrans, BEAM *beams )
{
	;
}

static intptr_t RefGetParm( int parm, int arg )
{
	dx_texture_t *glt;

	switch (parm)
	{
	case PARM_TEX_WIDTH:
		glt = R_GetTexture(arg);
		return glt->width;
	case PARM_TEX_HEIGHT:
		glt = R_GetTexture(arg);
		return glt->height;
	case PARM_TEX_SRC_WIDTH:
		glt = R_GetTexture(arg);
		return glt->srcWidth;
	case PARM_TEX_SRC_HEIGHT:
		glt = R_GetTexture(arg);
		return glt->srcHeight;
	case PARM_TEX_GLFORMAT:
		glt = R_GetTexture(arg);
		return 0;
	case PARM_TEX_ENCODE:
		glt = R_GetTexture(arg);
		return 0;
	case PARM_TEX_MIPCOUNT:
		glt = R_GetTexture(arg);
		return glt->numMips;
	case PARM_TEX_DEPTH:
		glt = R_GetTexture(arg);
		return 1;
#if 0
	case PARM_TEX_SKYBOX:
		Assert(arg >= 0 && arg < 6);
		return tr.skyboxTextures[arg];
#endif
	case PARM_TEX_SKYTEXNUM:
		return tr.skytexturenum;
#if 0
	case PARM_TEX_LIGHTMAP:
		arg = bound(0, arg, MAX_LIGHTMAPS - 1);
		return tr.lightmapTextures[arg];
#endif
	case PARM_TEX_TARGET:
		glt = R_GetTexture(arg);
		return 0;
	case PARM_TEX_TEXNUM:
		glt = R_GetTexture(arg);
		return arg;
	case PARM_TEX_FLAGS:
		glt = R_GetTexture(arg);
		return glt->flags;
#if 0
	case PARM_TEX_MEMORY:
		return GL_TexMemory();
	case PARM_ACTIVE_TMU:
		return glState.activeTMU;
#endif
	case PARM_LIGHTSTYLEVALUE:
		arg = bound(0, arg, MAX_LIGHTSTYLES - 1);
		return g_lightstylevalue[arg];
#if 0
	case PARM_MAX_IMAGE_UNITS:
		return GL_MaxTextureUnits();
	case PARM_REBUILD_GAMMA:
		return glConfig.softwareGammaUpdate;
	case PARM_GL_CONTEXT_TYPE:
		return glConfig.context;
	case PARM_GLES_WRAPPER:
		return glConfig.wrapper;
#endif
	case PARM_STENCIL_ACTIVE:
		return 0;//No stencil in dx2
	case PARM_TEX_FILTERING:
		return 0;
#if 0
		if (arg < 0)
			return gl_texture_nearest.value == 0.0f;

		return GL_TextureFilteringEnabled(R_GetTexture(arg));
#endif
	case PARM_GET_STUDIO_HDR:
		//return (intptr_t)R_StudioGetHeader();
		return 0;
	default:
		return (*gEngfuncs.EngineGetParm)(parm, arg);
	}
	return 0;
}


void GL_Bind( int tmu, unsigned int texnum )
{
	const dx_texture_t *texture;

	// missed or invalid texture?
	if( texnum <= 0 || texnum >= MAX_TEXTURES )
	{
		if( texnum != 0 )
			gEngfuncs.Con_DPrintf( S_ERROR "%s: invalid texturenum %d\n", __func__, texnum );
		texnum = tr.defaultTexture;
	}

	texture = R_GetTexture( texnum );

	//if( dxc.currentTexture == texture->d3dHandle )
	//	return;

	dxc.currentTexture = texture->d3dHandle;
}

static qboolean R_SpeedsMessage( char *out, size_t size )
{
	return false;
}

static void R_NewMap( void )
{
	tr.worldmodel = gp_cl->models[1];

	// clear out efrags in case the level hasn't been reloaded
	for( int i = 0; i < tr.worldmodel->numleafs; i++ )
		tr.worldmodel->leafs[i+1].efrags = NULL;

	tr.skytexturenum = -1;

	// clearing texture chains
	for( int i = 0; i < tr.worldmodel->numtextures; i++ )
	{
		if( !tr.worldmodel->textures[i] )
			continue;

		texture_t *tx = tr.worldmodel->textures[i];

		if( !Q_strncmp( tx->name, "sky", 3 ) && tx->width == ( tx->height * 2 ))
			tr.skytexturenum = i;

		tx->texturechain = NULL;
	}

	GL_BuildLightmaps();

	if( gEngfuncs.drawFuncs->R_NewMap != NULL )
		gEngfuncs.drawFuncs->R_NewMap();
}

static void Color4f( float r, float g, float b, float a )
{
	Vector4Set(dxc.currentColor, r, g, b, a);
}

static void Color4ub( unsigned char r, unsigned char g, unsigned char b, unsigned char a )
{
	Vector4Set(dxc.currentColor, r/255.f, g/255.f, b/255.f, a/255.f);
}

static void Vertex3fv( const float *worldPnt )
{
	;
}

static void Vertex3f( float x, float y, float z )
{
	;
}

static void CullFace( TRICULLSTYLE mode )
{
	;
}

static void VGUI_SetupDrawing( qboolean rect )
{
	;
}

static void R_FillRenderAPI( render_api_t *api )
{
	;
}

static void R_FillTriAPI( triangleapi_t *api )
{
	;
}

const ref_interface_t gReffuncs =
{
	.R_Init                = R_Init,
	.R_Shutdown            = R_Shutdown,
	.R_GetConfigName       = R_GetConfigName,
	.R_SetDisplayTransform = R_SetDisplayTransform,

	.GL_SetupAttributes = GL_SetupAttributes,
	.GL_InitExtensions  = GL_InitExtensions,
	.GL_ClearExtensions = GL_ClearExtensions,

	.R_GammaChanged       = R_GammaChanged,
	.R_BeginFrame         = R_BeginFrame,
	.R_RenderScene        = R_RenderScene,
	.R_EndFrame           = R_EndFrame,
	.R_PushScene          = R_SimpleStub,
	.R_PopScene           = R_SimpleStub,
	.GL_BackendStartFrame = GL_BackendStartFrame,
	.GL_BackendEndFrame   = GL_BackendEndFrame,

	.R_ClearScreen    = R_SimpleStub,
	.R_AllowFog       = R_AllowFog,
	.GL_SetRenderMode = GL_SetRenderMode,

	.R_AddEntity      = R_AddEntity,
	.R_ProcessEntData = R_ProcessEntData,

	.R_ShowTextures = R_ShowTextures,

	.R_GetTextureOriginalBuffer = R_GetTextureOriginalBuffer,
	.GL_LoadTextureFromBuffer   = GL_LoadTextureFromBuffer,
	.GL_ProcessTexture          = GL_ProcessTexture,
	.R_SetupSky                 = R_SetupSky,

	.R_Set2DMode      = R_Set2DMode,
	.R_DrawStretchPic = R_DrawStretchPic,
	.FillRGBA         = FillRGBA,
	.WorldToScreen    = WorldToScreen,

	.VID_ScreenShot  = VID_ScreenShot,
	.VID_CubemapShot = VID_CubemapShot,

	.R_LightPoint = R_LightPoint,

	.R_DecalShoot      = R_DecalShoot,
	.R_DecalRemoveAll  = R_SimpleStubInt,
	.R_CreateDecalList = R_CreateDecalList,
	.R_ClearAllDecals  = R_SimpleStub,

	.R_StudioEstimateFrame = R_StudioEstimateFrame,
	.R_StudioLerpMovement  = R_StudioLerpMovement,
	.R_StudioFillAPI = R_StudioFillAPI,
	.R_StudioSetDrawInterface = R_StudioSetDrawInterface,

	.R_SetSkyCloudsTextures     = R_SetSkyCloudsTextures,
	.GL_SubdivideSurface = GL_SubdivideSurface,
	.CL_RunLightStyles   = CL_RunLightStyles,

	.Mod_ProcessRenderData  = Mod_ProcessRenderData,
	.Mod_StudioLoadTextures = Mod_StudioLoadTextures,

	.CL_DrawParticles = CL_DrawParticles,
	.CL_DrawTracers   = CL_DrawTracers,
	.CL_DrawBeams     = CL_DrawBeams,

	.RefGetParm = RefGetParm,

	.R_GetDetailScaleForTexture = R_GetDetailScaleForTexture,
	.R_SetDetailScaleForTexture = R_SetDetailScaleForTexture,

	.GL_CreateTexture = GL_CreateTexture,
	.GL_FindTexture = GL_FindTexture,
	.GL_TextureName = GL_TextureName,
	.GL_TextureData = GL_TextureData,
	.GL_LoadTexture = GL_LoadTexture,
	.GL_FreeTexture = GL_FreeTexture,
	.R_OverrideTextureSourceSize = R_OverrideTextureSourceSize,
	.GL_UpdateTexture = GL_UpdateTexture,

	.GL_Bind = GL_Bind,

	.GL_RenderFrame    = R_RenderFrame,
	.GL_OrthoBounds    = GL_OrthoBounds,
	.R_SpeedsMessage   = R_SpeedsMessage,
	.Mod_GetCurrentVis = Mod_GetCurrentVis,
	.R_NewMap          = R_NewMap,
	.R_ClearScene      = R_ClearScene,

	.TriRenderMode = R_SimpleStubInt,
	.Begin         = R_SimpleStubInt,
	.End           = R_SimpleStub,
	.Color4f       = Color4f,
	.Color4ub      = Color4ub,
	.Vertex3fv     = Vertex3fv,
	.Vertex3f      = Vertex3f,
	.CullFace      = CullFace,

	.R_FillRenderAPI = R_FillRenderAPI,
	.R_FillTriAPI    = R_FillTriAPI,

	.VGUI_SetupDrawing   = VGUI_SetupDrawing,
};