/* SPDX-License-Identifier: BSD-2-Clause */
/*
 * Copyright (C) 2019-2021, Raspberry Pi (Trading) Ltd.
 *
 * rpi.cpp - Raspberry Pi Image Processing Algorithms
 */

#include <algorithm>
#include <array>
#include <fcntl.h>
#include <math.h>
#include <stdint.h>
#include <string.h>
#include <sys/mman.h>

#include <libcamera/buffer.h>
#include <libcamera/control_ids.h>
#include <libcamera/controls.h>
#include <libcamera/file_descriptor.h>
#include <libcamera/ipa/ipa_interface.h>
#include <libcamera/ipa/ipa_module_info.h>
#include <libcamera/ipa/raspberrypi.h>
#include <libcamera/ipa/raspberrypi_ipa_interface.h>
#include <libcamera/request.h>
#include <libcamera/span.h>

#include "libcamera/internal/buffer.h"
#include "libcamera/internal/log.h"

#include <linux/bcm2835-isp.h>

#include "agc_algorithm.hpp"
#include "agc_status.h"
#include "alsc_status.h"
#include "awb_algorithm.hpp"
#include "awb_status.h"
#include "black_level_status.h"
#include "cam_helper.hpp"
#include "ccm_algorithm.hpp"
#include "ccm_status.h"
#include "contrast_algorithm.hpp"
#include "contrast_status.h"
#include "controller.hpp"
#include "denoise_algorithm.hpp"
#include "denoise_status.h"
#include "dpc_status.h"
#include "focus_status.h"
#include "geq_status.h"
#include "lux_status.h"
#include "metadata.hpp"
#include "noise_status.h"
#include "sharpen_algorithm.hpp"
#include "sharpen_status.h"

namespace libcamera {

/* Configure the sensor with these values initially. */
constexpr double DefaultAnalogueGain = 1.0;
constexpr unsigned int DefaultExposureTime = 20000;
constexpr double defaultMinFrameDuration = 1e6 / 30.0;
constexpr double defaultMaxFrameDuration = 1e6 / 0.01;

/*
 * Determine the minimum allowable inter-frame duration (in us) to run the
 * controller algorithms. If the pipeline handler provider frames at a rate
 * higher than this, we rate-limit the controller Prepare() and Process() calls
 * to lower than or equal to this rate.
 */
constexpr double controllerMinFrameDuration = 1e6 / 60.0;

LOG_DEFINE_CATEGORY(IPARPI)

class IPARPi : public ipa::RPi::IPARPiInterface
{
public:
	IPARPi()
		: controller_(), frameCount_(0), checkCount_(0), mistrustCount_(0),
		  lastRunTimestamp_(0), lsTable_(nullptr), firstStart_(true)
	{
	}

	~IPARPi()
	{
		if (lsTable_)
			munmap(lsTable_, ipa::RPi::MaxLsGridSize);
	}

	int init(const IPASettings &settings, ipa::RPi::SensorConfig *sensorConfig) override;
	void start(const ControlList &controls, ipa::RPi::StartConfig *startConfig) override;
	void stop() override {}

	int configure(const IPACameraSensorInfo &sensorInfo,
		      const std::map<unsigned int, IPAStream> &streamConfig,
		      const std::map<unsigned int, ControlInfoMap> &entityControls,
		      const ipa::RPi::IPAConfig &data,
		      ControlList *controls) override;
	void mapBuffers(const std::vector<IPABuffer> &buffers) override;
	void unmapBuffers(const std::vector<unsigned int> &ids) override;
	void signalStatReady(const uint32_t bufferId) override;
	void signalQueueRequest(const ControlList &controls) override;
	void signalIspPrepare(const ipa::RPi::ISPConfig &data) override;

private:
	void setMode(const IPACameraSensorInfo &sensorInfo);
	bool validateSensorControls();
	bool validateIspControls();
	void queueRequest(const ControlList &controls);
	void returnEmbeddedBuffer(unsigned int bufferId);
	void prepareISP(const ipa::RPi::ISPConfig &data);
	void reportMetadata();
	void fillDeviceStatus(const ControlList &sensorControls);
	void processStats(unsigned int bufferId);
	void applyFrameDurations(double minFrameDuration, double maxFrameDuration);
	void applyAGC(const struct AgcStatus *agcStatus, ControlList &ctrls);
	void applyAWB(const struct AwbStatus *awbStatus, ControlList &ctrls);
	void applyDG(const struct AgcStatus *dgStatus, ControlList &ctrls);
	void applyCCM(const struct CcmStatus *ccmStatus, ControlList &ctrls);
	void applyBlackLevel(const struct BlackLevelStatus *blackLevelStatus, ControlList &ctrls);
	void applyGamma(const struct ContrastStatus *contrastStatus, ControlList &ctrls);
	void applyGEQ(const struct GeqStatus *geqStatus, ControlList &ctrls);
	void applyDenoise(const struct DenoiseStatus *denoiseStatus, ControlList &ctrls);
	void applySharpen(const struct SharpenStatus *sharpenStatus, ControlList &ctrls);
	void applyDPC(const struct DpcStatus *dpcStatus, ControlList &ctrls);
	void applyLS(const struct AlscStatus *lsStatus, ControlList &ctrls);
	void resampleTable(uint16_t dest[], double const src[12][16], int destW, int destH);

	std::map<unsigned int, MappedFrameBuffer> buffers_;

	ControlInfoMap sensorCtrls_;
	ControlInfoMap ispCtrls_;
	ControlList libcameraMetadata_;

	/* Camera sensor params. */
	CameraMode mode_;

	/* Raspberry Pi controller specific defines. */
	std::unique_ptr<RPiController::CamHelper> helper_;
	RPiController::Controller controller_;
	RPiController::Metadata rpiMetadata_;

	/*
	 * We count frames to decide if the frame must be hidden (e.g. from
	 * display) or mistrusted (i.e. not given to the control algos).
	 */
	uint64_t frameCount_;

	/* For checking the sequencing of Prepare/Process calls. */
	uint64_t checkCount_;

	/* How many frames we should avoid running control algos on. */
	unsigned int mistrustCount_;

	/* Number of frames that need to be dropped on startup. */
	unsigned int dropFrameCount_;

	/* Frame timestamp for the last run of the controller. */
	uint64_t lastRunTimestamp_;

	/* Do we run a Controller::process() for this frame? */
	bool processPending_;

	/* LS table allocation passed in from the pipeline handler. */
	FileDescriptor lsTableHandle_;
	void *lsTable_;

	/* Distinguish the first camera start from others. */
	bool firstStart_;

	/* Frame duration (1/fps) limits, given in microseconds. */
	double minFrameDuration_;
	double maxFrameDuration_;
};

int IPARPi::init(const IPASettings &settings, ipa::RPi::SensorConfig *sensorConfig)
{
	/*
	 * Load the "helper" for this sensor. This tells us all the device specific stuff
	 * that the kernel driver doesn't. We only do this the first time; we don't need
	 * to re-parse the metadata after a simple mode-switch for no reason.
	 */