// Copyright (c) 2012- 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 <vector>
#include "Common/CommonTypes.h"
#include "Core/MemMap.h"
#include "GPU/GPUState.h"
#include "GPU/ge_constants.h"

enum {
	FB_USAGE_DISPLAYED_FRAMEBUFFER = 1,
	FB_USAGE_RENDERTARGET = 2,
	FB_USAGE_TEXTURE = 4,
};

enum {
	FB_NON_BUFFERED_MODE = 0,
	FB_BUFFERED_MODE = 1,

	// Hm, it's unfortunate that GPU has ended up as two separate values in GL and GLES.
#ifndef USING_GLES2
	FB_READFBOMEMORY_CPU = 2,
	FB_READFBOMEMORY_GPU = 3,
#else
	FB_READFBOMEMORY_GPU = 2,
#endif
	FBO_READFBOMEMORY_MIN = 2
};

struct FBO;

struct VirtualFramebuffer {
	int last_frame_used;
	int last_frame_attached;
	int last_frame_render;
	bool memoryUpdated;
	bool depthUpdated;

	u32 fb_address;
	u32 z_address;
	int fb_stride;
	int z_stride;

	// There's also a top left of the drawing region, but meh...

	// width/height: The detected size of the current framebuffer.
	u16 width;
	u16 height;
	// renderWidth/renderHeight: The actual size we render at. May be scaled to render at higher resolutions.
	u16 renderWidth;
	u16 renderHeight;
	// bufferWidth/bufferHeight: The actual (but non scaled) size of the buffer we render to. May only be bigger than width/height.
	u16 bufferWidth;
	u16 bufferHeight;

	u16 usageFlags;

	u16 newWidth;
	u16 newHeight;
	int lastFrameNewSize;

	GEBufferFormat format;  // virtual, right now they are all RGBA8888
	// TODO: Handle fbo and colorDepth better.
	u8 colorDepth;
	FBO *fbo;

	u16 drawnWidth;
	u16 drawnHeight;
	GEBufferFormat drawnFormat;

	bool dirtyAfterDisplay;
	bool reallyDirtyAfterDisplay;  // takes frame skipping into account
};

class FramebufferManagerCommon {
public:
	FramebufferManagerCommon();
	virtual ~FramebufferManagerCommon();

	void BeginFrame();
	void SetDisplayFramebuffer(u32 framebuf, u32 stride, GEBufferFormat format);

	void DoSetRenderFrameBuffer();
	void SetRenderFrameBuffer() {
		// Inlining this part since it's so frequent.
		if (!gstate_c.framebufChanged && currentRenderVfb_) {
			currentRenderVfb_->last_frame_render = gpuStats.numFlips;
			currentRenderVfb_->dirtyAfterDisplay = true;
			if (!gstate_c.skipDrawReason)
				currentRenderVfb_->reallyDirtyAfterDisplay = true;
			return;
		}
		DoSetRenderFrameBuffer();
	}
	virtual void RebindFramebuffer() = 0;

	void UpdateFromMemory(u32 addr, int size, bool safe);
	virtual bool NotifyFramebufferCopy(u32 src, u32 dest, int size, bool isMemset = false) = 0;
	virtual bool NotifyStencilUpload(u32 addr, int size, bool skipZero = false) = 0;

	virtual void ReadFramebufferToMemory(VirtualFramebuffer *vfb, bool sync, int x, int y, int w, int h) = 0;
	virtual void MakePixelTexture(const u8 *srcPixels, GEBufferFormat srcPixelFormat, int srcStride, int width, int height) = 0;
	virtual void DrawPixels(VirtualFramebuffer *vfb, int dstX, int dstY, const u8 *srcPixels, GEBufferFormat srcPixelFormat, int srcStride, int width, int height) = 0;
	virtual void DrawFramebuffer(const u8 *srcPixels, GEBufferFormat srcPixelFormat, int srcStride, bool applyPostShader) = 0;

	size_t NumVFBs() const { return vfbs_.size(); }

	u32 PrevDisplayFramebufAddr() {
		return prevDisplayFramebuf_ ? (0x04000000 | prevDisplayFramebuf_->fb_address) : 0;
	}
	u32 DisplayFramebufAddr() {
		return displayFramebuf_ ? (0x04000000 | displayFramebuf_->fb_address) : 0;
	}

	bool MayIntersectFramebuffer(u32 start) {
		// Clear the cache/kernel bits.
		start = start & 0x3FFFFFFF;
		// Most games only have two framebuffers at the start.
		if (start >= framebufRangeEnd_ || start < PSP_GetVidMemBase()) {
			return false;
		}
		return true;
	}

	// TODO: Break out into some form of FBO manager
	VirtualFramebuffer *GetVFBAt(u32 addr);
	VirtualFramebuffer *GetDisplayVFB() {
		return GetVFBAt(displayFramebufPtr_);
	}

	int GetRenderWidth() const { return currentRenderVfb_ ? currentRenderVfb_->renderWidth : 480; }
	int GetRenderHeight() const { return currentRenderVfb_ ? currentRenderVfb_->renderHeight : 272; }
	int GetTargetWidth() const { return currentRenderVfb_ ? currentRenderVfb_->width : 480; }
	int GetTargetHeight() const { return currentRenderVfb_ ? currentRenderVfb_->height : 272; }
	int GetTargetBufferWidth() const { return currentRenderVfb_ ? currentRenderVfb_->bufferWidth : 480; }
	int GetTargetBufferHeight() const { return currentRenderVfb_ ? currentRenderVfb_->bufferHeight : 272; }
	int GetTargetStride() const { return currentRenderVfb_ ? currentRenderVfb_->fb_stride : 512; }
	GEBufferFormat GetTargetFormat() const { return currentRenderVfb_ ? currentRenderVfb_->format : displayFormat_; }

	void SetDepthUpdated() {
		if (currentRenderVfb_) {
			currentRenderVfb_->depthUpdated = true;
		}
	}
	void SetColorUpdated() {
		if (currentRenderVfb_) {
			SetColorUpdated(currentRenderVfb_);
		}
	}

protected:
	virtual void DisableState() = 0;
	virtual void ClearBuffer() = 0;
	virtual void ClearDepthBuffer() = 0;
	virtual void FlushBeforeCopy() = 0;
	virtual void DecimateFBOs() = 0;

	void EstimateDrawingSize(int &drawing_width, int &drawing_height);
	u32 FramebufferByteSize(const VirtualFramebuffer *vfb) const;
	static bool MaskedEqual(u32 addr1, u32 addr2);

	virtual void DestroyFramebuf(VirtualFramebuffer *vfb) = 0;
	virtual void ResizeFramebufFBO(VirtualFramebuffer *vfb, u16 w, u16 h, bool force = false) = 0;
	virtual void NotifyRenderFramebufferCreated(VirtualFramebuffer *vfb) = 0;
	virtual void NotifyRenderFramebufferSwitched(VirtualFramebuffer *prevVfb, VirtualFramebuffer *vfb) = 0;
	virtual void NotifyRenderFramebufferUpdated(VirtualFramebuffer *vfb, bool vfbFormatChanged) = 0;

	bool ShouldDownloadFramebuffer(const VirtualFramebuffer *vfb) const;

	void SetColorUpdated(VirtualFramebuffer *dstBuffer) {
		dstBuffer->memoryUpdated = false;
		dstBuffer->dirtyAfterDisplay = true;
		dstBuffer->drawnWidth = dstBuffer->width;
		dstBuffer->drawnHeight = dstBuffer->height;
		dstBuffer->drawnFormat = dstBuffer->format;
		if ((gstate_c.skipDrawReason & SKIPDRAW_SKIPFRAME) == 0)
			dstBuffer->reallyDirtyAfterDisplay = true;
	}

	u32 displayFramebufPtr_;
	u32 displayStride_;
	GEBufferFormat displayFormat_;

	VirtualFramebuffer *displayFramebuf_;
	VirtualFramebuffer *prevDisplayFramebuf_;
	VirtualFramebuffer *prevPrevDisplayFramebuf_;
	int frameLastFramebufUsed_;

	VirtualFramebuffer *currentRenderVfb_;

	// The range of PSP memory that may contain FBOs.  So we can skip iterating.
	u32 framebufRangeEnd_;

	bool useBufferedRendering_;
	bool updateVRAM_;

	std::vector<VirtualFramebuffer *> vfbs_;

	bool hackForce04154000Download_;

	// Aggressively delete unused FBOs to save gpu memory.
	enum {
		FBO_OLD_AGE = 5,
	};
};