// Copyright (c) 2015- PPSSPP Project.

// 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, version 2.0 or later versions.

// 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 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.

#pragma once

#include <cstdint>
#include <vector>

namespace Draw {
	class DrawContext;
}

enum ShaderLanguage {
	GLSL_140,
	GLSL_300,
	GLSL_VULKAN,
	HLSL_DX9,
	HLSL_D3D11,
	HLSL_D3D11_LEVEL9,
};

enum DebugShaderType {
	SHADER_TYPE_VERTEX = 0,
	SHADER_TYPE_FRAGMENT = 1,
	SHADER_TYPE_GEOMETRY = 2,
	SHADER_TYPE_VERTEXLOADER = 3,  // Not really a shader, but might as well re-use this mechanism
	SHADER_TYPE_PIPELINE = 4,  // Vulkan and DX12 combines a bunch of state into pipeline objects. Might as well make them inspectable.
	SHADER_TYPE_DEPAL = 5,
	SHADER_TYPE_SAMPLER = 6,  // Not really a shader either. Need to rename this enum...
};

enum DebugShaderStringType {
	SHADER_STRING_SHORT_DESC = 0,
	SHADER_STRING_SOURCE_CODE = 1,
	SHADER_STRING_STATS = 2,
};

// Shared between the backends. Not all are necessarily used by each backend, but this lets us share
// more code than before.
enum : uint64_t {
	DIRTY_PROJMATRIX = 1ULL << 0,
	DIRTY_PROJTHROUGHMATRIX = 1ULL << 1,
	DIRTY_FOGCOLOR = 1ULL << 2,
	DIRTY_FOGCOEF = 1ULL << 3,
	DIRTY_TEXENV = 1ULL << 4,
	DIRTY_ALPHACOLORREF = 1ULL << 5,

	DIRTY_STENCILREPLACEVALUE = 1ULL << 6,

	DIRTY_ALPHACOLORMASK = 1ULL << 7,
	DIRTY_LIGHT0 = 1ULL << 8,
	DIRTY_LIGHT1 = 1ULL << 9,
	DIRTY_LIGHT2 = 1ULL << 10,
	DIRTY_LIGHT3 = 1ULL << 11,

	DIRTY_MATDIFFUSE = 1ULL << 12,
	DIRTY_MATSPECULAR = 1ULL << 13,
	DIRTY_MATEMISSIVE = 1ULL << 14,
	DIRTY_AMBIENT = 1ULL << 15,
	DIRTY_MATAMBIENTALPHA = 1ULL << 16,

	DIRTY_SHADERBLEND = 1ULL << 17,  // Used only for in-shader blending.

	DIRTY_UVSCALEOFFSET = 1ULL << 18,
	DIRTY_DEPTHRANGE = 1ULL << 19,

	DIRTY_WORLDMATRIX = 1ULL << 21,
	DIRTY_VIEWMATRIX = 1ULL << 22,
	DIRTY_TEXMATRIX = 1ULL << 23,
	DIRTY_BONEMATRIX0 = 1ULL << 24,  // NOTE: These must be under 32
	DIRTY_BONEMATRIX1 = 1ULL << 25,
	DIRTY_BONEMATRIX2 = 1ULL << 26,
	DIRTY_BONEMATRIX3 = 1ULL << 27,
	DIRTY_BONEMATRIX4 = 1ULL << 28,
	DIRTY_BONEMATRIX5 = 1ULL << 29,
	DIRTY_BONEMATRIX6 = 1ULL << 30,
	DIRTY_BONEMATRIX7 = 1ULL << 31,

	DIRTY_BEZIERSPLINE = 1ULL << 32,
	DIRTY_TEXCLAMP = 1ULL << 33,
	DIRTY_CULLRANGE = 1ULL << 34,

	DIRTY_DEPAL = 1ULL << 35,

	// space for 5 more uniform dirty flags. Remember to update DIRTY_ALL_UNIFORMS.

	DIRTY_BONE_UNIFORMS = 0xFF000000ULL,

	DIRTY_ALL_UNIFORMS = 0xFFFFFFFFFULL,
	DIRTY_ALL_LIGHTS = DIRTY_LIGHT0 | DIRTY_LIGHT1 | DIRTY_LIGHT2 | DIRTY_LIGHT3,

	// Other dirty elements that aren't uniforms!
	DIRTY_FRAMEBUF = 1ULL << 40,
	DIRTY_TEXTURE_IMAGE = 1ULL << 41,  // Means that the definition of the texture image has changed (address, stride etc), and we need to look up again.
	DIRTY_TEXTURE_PARAMS = 1ULL << 42,

	// Render State
	DIRTY_BLEND_STATE = 1ULL << 43,
	DIRTY_DEPTHSTENCIL_STATE = 1ULL << 44,
	DIRTY_RASTER_STATE = 1ULL << 45,
	DIRTY_VIEWPORTSCISSOR_STATE = 1ULL << 46,
	DIRTY_VERTEXSHADER_STATE = 1ULL << 47,
	DIRTY_FRAGMENTSHADER_STATE = 1ULL << 48,

	DIRTY_ALL = 0xFFFFFFFFFFFFFFFF
};

class ShaderManagerCommon {
public:
	ShaderManagerCommon(Draw::DrawContext *draw) : draw_(draw) {}
	virtual ~ShaderManagerCommon() {}

	virtual void DirtyLastShader() = 0;

protected:
	Draw::DrawContext *draw_ = nullptr;
};

struct TBuiltInResource;
void init_resources(TBuiltInResource &Resources);

enum DoLightComputation {
	LIGHT_OFF,
	LIGHT_SHADE,
	LIGHT_FULL,
};

struct GLSLShaderCompat {
	const char *versionString;
	const char *varying;
	const char *attribute;
	const char *fragColor0;
	const char *fragColor1;
	const char *texture;
	const char *texelFetch;
	const char *lastFragData;
	bool gles;
	bool glslES30;
	bool bitwiseOps;
};