/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2023, Linaro Ltd
 * Copyright (C) 2023, Red Hat Inc.
 *
 * Authors:
 * Hans de Goede <hdegoede@redhat.com>
 *
 * CPU based software statistics implementation
 */

#pragma once

#include <stdint.h>
#include <vector>

#include <libcamera/base/signal.h>

#include <libcamera/geometry.h>

#include "libcamera/internal/bayer_format.h"
#include "libcamera/internal/framebuffer.h"
#include "libcamera/internal/shared_mem_object.h"
#include "libcamera/internal/software_isp/swisp_stats.h"

#include "benchmark.h"

namespace libcamera {

class CameraManager;
class MappedFrameBuffer;
class PixelFormat;
struct StreamConfiguration;

class SwStatsCpu
{
public:
	SwStatsCpu(const CameraManager &cm);
	~SwStatsCpu() = default;

	/*
	 * The combination of pipeline + sensor delays means that
	 * exposure changes can take up to 3 frames to get applied,
	 * Run stats once every 4 frames to ensure any previous
	 * exposure changes have been applied.
	 */
	static constexpr uint32_t kStatPerNumFrames = 4;

	bool isValid() const { return sharedStats_.fd().isValid(); }

	const SharedFD &getStatsFD() { return sharedStats_.fd(); }

	const Size &patternSize() { return patternSize_; }

	int configure(const StreamConfiguration &inputCfg, unsigned int statsBufferCount = 1);
	void setWindow(const Rectangle &window);
	void startFrame(uint32_t frame);
	void finishFrame(uint32_t frame, uint32_t bufferId);
	void processFrame(uint32_t frame, uint32_t bufferId, FrameBuffer *input);

	void processLine0(uint32_t frame, unsigned int y, const uint8_t *src[], unsigned int statsBufferIndex = 0)
	{
		if (frame % kStatPerNumFrames)
			return;

		if ((y & ySkipMask_) || y < static_cast<unsigned int>(window_.y) ||
		    y >= (window_.y + window_.height))
			return;

		(this->*stats0_)(src, stats_[statsBufferIndex]);
	}

	void processLine2(uint32_t frame, unsigned int y, const uint8_t *src[], unsigned int statsBufferIndex = 0)
	{
		if (frame % kStatPerNumFrames)
			return;

		if ((y & ySkipMask_) || y < static_cast<unsigned int>(window_.y) ||
		    y >= (window_.y + window_.height))
			return;

		(this->*stats2_)(src, stats_[statsBufferIndex]);
	}

	Signal<uint32_t, uint32_t> statsReady;

private:
	using statsProcessFn = void (SwStatsCpu::*)(const uint8_t *src[], SwIspStats &stats);
	using processFrameFn = void (SwStatsCpu::*)(MappedFrameBuffer &in);

	int setupStandardBayerOrder(BayerFormat::Order order);
	/* Bayer 8 bpp unpacked */
	void statsBGGR8Line0(const uint8_t *src[], SwIspStats &stats);
	/* Bayer 10 bpp unpacked */
	void statsBGGR10Line0(const uint8_t *src[], SwIspStats &stats);
	/* Bayer 12 bpp unpacked */
	void statsBGGR12Line0(const uint8_t *src[], SwIspStats &stats);
	/* Bayer 10 bpp packed */
	void statsBGGR10PLine0(const uint8_t *src[], SwIspStats &stats);
	void statsGBRG10PLine0(const uint8_t *src[], SwIspStats &stats);

	void processBayerFrame2(MappedFrameBuffer &in);

	processFrameFn processFrame_;

	/* Variables set by configure(), used every line */
	statsProcessFn stats0_;
	statsProcessFn stats2_;
	bool swapLines_;

	unsigned int ySkipMask_;

	Rectangle window_;

	Size patternSize_;

	unsigned int xShift_;
	unsigned int stride_;

	std::vector<SwIspStats> stats_;
	SharedMemObject<SwIspStats> sharedStats_;
	Benchmark bench_;
};

} /* namespace libcamera */