//-----------------------------------------------------------------------------
//
// Copyright 1993-1996 id Software
// Copyright 1999-2016 Randy Heit
// Copyright 2016 Magnus Norddahl
//
// 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.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see http://www.gnu.org/licenses/
//
//-----------------------------------------------------------------------------
//


#pragma once

#include "r_defs.h"

namespace swrenderer
{
	struct FWallCoords;
	struct DrawSegmentClipInfo;

	enum class ProjectedWallCull
	{
		Visible,
		OutsideAbove,
		OutsideBelow
	};

	class ProjectedWallLine
	{
	public:
		short ScreenY[MAXWIDTH];

		ProjectedWallCull Project(RenderViewport *viewport, double z1, double z2, const FWallCoords *wallc);
		ProjectedWallCull Project(RenderViewport *viewport, const secplane_t &plane, const FWallCoords *wallc, seg_t *line, bool xflip);
		ProjectedWallCull Project(RenderViewport *viewport, double z, const FWallCoords *wallc);

		void ClipTop(int x1, int x2, const DrawSegmentClipInfo& clip);
		void ClipBottom(int x1, int x2, const DrawSegmentClipInfo& clip);
	};

	struct FWallTmapVals
	{
		void InitFromWallCoords(RenderThread* thread, const FWallCoords* wallc);
		void InitFromLine(RenderThread* thread, seg_t* line);

	private:
		float UoverZorg, UoverZstep;
		float InvZorg, InvZstep;

		friend class ProjectedWallTexcoords;
	};

	class ProjectedWallTexcoords
	{
	public:
		void ProjectTop(RenderViewport* viewport, sector_t* frontsector, sector_t* backsector, seg_t* lineseg, int x1, int x2, const FWallTmapVals& WallT, FSoftwareTexture* pic);
		void ProjectMid(RenderViewport* viewport, sector_t* frontsector, seg_t* lineseg, int x1, int x2, const FWallTmapVals& WallT, FSoftwareTexture* pic);
		void ProjectBottom(RenderViewport* viewport, sector_t* frontsector, sector_t* backsector, seg_t* lineseg, int x1, int x2, const FWallTmapVals& WallT, FSoftwareTexture* pic);
		void ProjectTranslucent(RenderViewport* viewport, sector_t* frontsector, sector_t* backsector, seg_t* lineseg, int x1, int x2, const FWallTmapVals& WallT, FSoftwareTexture* pic);
		void Project3DFloor(RenderViewport* viewport, F3DFloor* rover, seg_t* lineseg, int x1, int x2, const FWallTmapVals& WallT, FSoftwareTexture* pic);
		void ProjectSprite(RenderViewport* viewport, double topZ, double scale, bool flipX, bool flipY, int x1, int x2, const FWallTmapVals& WallT, FSoftwareTexture* pic);

		float VStep(int x) const;
		fixed_t UPos(int x) const;

	private:
		void Project(RenderViewport* viewport, double walxrepeat, int x1, int x2, const FWallTmapVals& WallT, bool flipx = false);

		static fixed_t GetXOffset(seg_t* lineseg, FSoftwareTexture* tex, side_t::ETexpart texpart);
		static double GetRowOffset(seg_t* lineseg, FSoftwareTexture* tex, side_t::ETexpart texpart);
		static double GetXScale(side_t* sidedef, FSoftwareTexture* tex, side_t::ETexpart texpart);
		static double GetYScale(side_t* sidedef, FSoftwareTexture* tex, side_t::ETexpart texpart);

		double CenterX;
		double WallTMapScale2;
		double walxrepeat;
		int x1;
		int x2;
		FWallTmapVals WallT;
		bool flipx;

		float yscale = 1.0f;
		fixed_t xoffset = 0;
		double texturemid = 0.0f;

		friend class RenderWallPart;
		friend class SpriteDrawerArgs;
	};

	class ProjectedWallLight
	{
	public:
		int GetLightLevel() const { return lightlevel; }
		bool GetFoggy() const { return foggy; }
		FDynamicColormap *GetBaseColormap() const { return basecolormap; }

		float GetLightPos(int x) const { return lightleft + lightstep * (x - x1); }
		float GetLightStep() const { return lightstep; }

		void SetColormap(const sector_t *frontsector, seg_t *lineseg, lightlist_t *lit = nullptr);

		void SetLightLeft(float left, float step, int startx) { lightleft = left; lightstep = step; x1 = startx; }
		void SetLightLeft(RenderThread *thread, const FWallCoords &wallc);

	private:
		int lightlevel;
		bool foggy;
		FDynamicColormap *basecolormap;

		int x1;
		float lightleft;
		float lightstep;
	};
}