/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2022, Theobroma Systems
 *
 * af.cpp - RkISP1 AF hill climbing based control algorithm
 */

#include "af.h"

/**
 * \file af.h
 */

namespace libcamera::ipa::rkisp1::algorithms {

/**
 * \class Af
 * \brief AF control algorithm
 */

LOG_DEFINE_CATEGORY(RkISP1Af)


static rkisp1_cif_isp_window rectangleToIspWindow(const Rectangle &rectangle)
{
	rkisp1_cif_isp_window ispwindow;

	ispwindow.h_offs = rectangle.x;
	ispwindow.v_offs = rectangle.y;
	ispwindow.h_size = rectangle.width;
	ispwindow.v_size = rectangle.height;

	return ispwindow;
}

/**
 * \copydoc libcamera::ipa::Algorithm::configure
 */
int Af::configure([[maybe_unused]] IPAContext &context,
		  const IPACameraSensorInfo &configInfo)
{
	/* Default AF window of 3/4 size of the screen placed at the center */
	defaultWindow_ = Rectangle(configInfo.outputSize.width / 8,
				   configInfo.outputSize.height / 8,
				   3 * configInfo.outputSize.width / 4,
				   3 * configInfo.outputSize.height / 4);
	updateCurrentWindow(defaultWindow_);

	return 0;
}

/**
 * \copydoc libcamera::ipa::Algorithm::prepare
 */
void Af::prepare([[maybe_unused]] IPAContext &context, rkisp1_params_cfg *params)
{
	if (updateAfwindow_) {
		params->meas.afc_config.num_afm_win = 1;
		params->meas.afc_config.thres = 128;
		params->meas.afc_config.var_shift = 4;
		/* \todo Allow setting thres and var_shift in tuning file */

		params->meas.afc_config.afm_win[0] = rectangleToIspWindow(currentWindow_);

		params->module_cfg_update |= RKISP1_CIF_ISP_MODULE_AFC;
		params->module_ens |= RKISP1_CIF_ISP_MODULE_AFC;
		params->module_en_update |= RKISP1_CIF_ISP_MODULE_AFC;

		updateAfwindow_ = false;
	}
}

/**
 * \copydoc libcamera::ipa::Algorithm::process
 */
void Af::process(IPAContext &context,
		 [[maybe_unused]] IPAFrameContext *frameCtx,
		 const rkisp1_stat_buffer *stats)
{
	uint32_t sharpness = stats->params.af.window[0].sum;
	uint32_t luminance = stats->params.af.window[0].lum;

	LOG(RkISP1Af, Debug) << "lensPosition: " << context.frameContext.af.focus
			     << ", Sharpness: " << sharpness
			     << ", Luminance: " << luminance;

	uint32_t lensPosition = processAutofocus(sharpness);

	context.frameContext.af.focus = lensPosition;
}

void Af::setMetering(controls::AfMeteringEnum metering)
{
	if (metering == meteringMode_)
		return;

	if (metering == controls::AfMeteringWindows) {
		updateCurrentWindow(userWindow_);
	} else {
		updateCurrentWindow(defaultWindow_);
	}

	meteringMode_ = metering;
}

void Af::setWindows(Span<const Rectangle> windows)
{
	if (windows.size() != 1) {
		LOG(RkISP1Af, Error) << "Only one AF window is supported";
		return;
	}

	/* \todo Check if window size is valid for ISP */

	LOG(RkISP1Af, Debug) << "setWindows: " << userWindow_;

	userWindow_ = windows[0];

	if (meteringMode_ == controls::AfMeteringWindows) {
		updateCurrentWindow(userWindow_);
	}
}

void Af::updateCurrentWindow(const Rectangle &window)
{
	currentWindow_ = window;
	updateAfwindow_ = true;
}

REGISTER_IPA_ALGORITHM(Af, "Af")

} /* namespace libcamera::ipa::rkisp1::algorithms */