/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * main.cpp - cam - The libcamera swiss army knife
 */

#include <atomic>
#include <iomanip>
#include <iostream>
#include <signal.h>
#include <string.h>

#include <libcamera/libcamera.h>
#include <libcamera/property_ids.h>

#include "camera_session.h"
#include "event_loop.h"
#include "main.h"
#include "options.h"
#include "stream_options.h"

using namespace libcamera;

class CamApp
{
public:
	CamApp();

	static CamApp *instance();

	int init(int argc, char **argv);
	void cleanup();

	int exec();
	void quit();

private:
	void cameraAdded(std::shared_ptr<Camera> cam);
	void cameraRemoved(std::shared_ptr<Camera> cam);
	void captureDone();
	int parseOptions(int argc, char *argv[]);
	int run();

	static std::string cameraName(const Camera *camera);

	static CamApp *app_;
	OptionsParser::Options options_;

	std::unique_ptr<CameraManager> cm_;

	std::atomic_uint loopUsers_;
	EventLoop loop_;
};

CamApp *CamApp::app_ = nullptr;

CamApp::CamApp()
	: loopUsers_(0)
{
	CamApp::app_ = this;
}

CamApp *CamApp::instance()
{
	return CamApp::app_;
}

int CamApp::init(int argc, char **argv)
{
	int ret;

	ret = parseOptions(argc, argv);
	if (ret < 0)
		return ret;

	cm_ = std::make_unique<CameraManager>();

	ret = cm_->start();
	if (ret) {
		std::cout << "Failed to start camera manager: "
			  << strerror(-ret) << std::endl;
		return ret;
	}

	return 0;
}

void CamApp::cleanup()
{
	cm_->stop();
}

int CamApp::exec()
{
	int ret;

	ret = run();
	cleanup();

	return ret;
}

void CamApp::quit()
{
	loop_.exit();
}

int CamApp::parseOptions(int argc, char *argv[])
{
	StreamKeyValueParser streamKeyValue;

	OptionsParser parser;
	parser.addOption(OptCamera, OptionString,
			 "Specify which camera to operate on, by id or by index", "camera",
			 ArgumentRequired, "camera", true);
	parser.addOption(OptHelp, OptionNone, "Display this help message",
			 "help");
	parser.addOption(OptInfo, OptionNone,
			 "Display information about stream(s)", "info");
	parser.addOption(OptList, OptionNone, "List all cameras", "list");
	parser.addOption(OptListControls, OptionNone, "List cameras controls",
			 "list-controls");
	parser.addOption(OptListProperties, OptionNone, "List cameras properties",
			 "list-properties");
	parser.addOption(OptMonitor, OptionNone,
			 "Monitor for hotplug and unplug camera events",
			 "monitor");

	/* Sub-options of OptCamera: */
	parser.addOption(OptCapture, OptionInteger,
			 "Capture until interrupted by user or until <count> frames captured",
			 "capture", ArgumentOptional, "count", false,
			 OptCamera);
#ifdef HAVE_KMS
	parser.addOption(OptDisplay, OptionString,
			 "Display viewfinder through DRM/KMS on specified connector",
			 "display", ArgumentOptional, "connector", false,
			 OptCamera);
#endif
	parser.addOption(OptFile, OptionString,
			 "Write captured frames to disk\n"
			 "If the file name ends with a '/', it sets the directory in which\n"
			 "to write files, using the default file name. Otherwise it sets the\n"
			 "full file path and name. The first '#' character in the file name\n"
			 "is expanded to the camera index, stream name and frame sequence number.\n"
			 "If the file name ends with '.dng', then the frame will be written to\n"
			 "the output file(s) in DNG format.\n"
			 "The default file name is 'frame-#.bin'.",
			 "file", ArgumentOptional, "filename", false,
			 OptCamera);
#ifdef HAVE_SDL
	parser.addOption(OptSDL, OptionNone, "Display viewfinder through SDL",
			 "sdl", ArgumentNone, "", false, OptCamera);
#endif
	parser.addOption(OptStream, &streamKeyValue,
			 "Set configuration of a camera stream", "stream", true,
			 OptCamera);
	parser.addOption(OptStrictFormats, OptionNone,
			 "Do not allow requested stream format(s) to be adjusted",
			 "strict-formats", ArgumentNone, nullptr, false,
			 OptCamera);
	parser.addOption(OptMetadata, OptionNone,
			 "Print the metadata for completed requests",
			 "metadata", ArgumentNone, nullptr, false,
			 OptCamera);
	parser.addOption(OptCaptureScript, OptionString,
			 "Load a capture session configuration script from a file",
			 "script", ArgumentRequired, "script", false,
			 OptCamera);

	options_ = parser.parse(argc, argv);
	if (!options_.valid())
		return -EINVAL;

	if (options_.empty() || options_.isSet(OptHelp)) {
		parser.usage();
		return options_.empty() ? -EINVAL : -EINTR;
	}

	return 0;
}

void CamApp::cameraAdded(std::shared_ptr<Camera> cam)
{
	std::cout << "Camera Added: " << cam->id() << std::endl;
}

void CamApp::cameraRemoved(std::shared_ptr<Camera> cam)
{
	std::cout << "Camera Removed: " << cam->id() << std::endl;
}

void CamApp::captureDone()
{
	if (--loopUsers_ == 0)
		EventLoop::instance()->exit(0);
}

int CamApp::run()
{
	int ret;

	/* 1. List all cameras. */
	if (options_.isSet(OptList)) {
		std::cout << "Available cameras:" << std::endl;

		unsigned int index = 1;
		for (const std::shared_ptr<Camera> &cam : cm_->cameras()) {
			std::cout << index << ": " << cameraName(cam.get()) << std::endl;
			index++;
		}
	}

	/* 2. Create the camera sessions. */
	std::vector<std::unique_ptr<CameraSession>> sessions;

	if (options_.isSet(OptCamera)) {
		unsigned int index = 0;

		for (const OptionValue &camera : options_[OptCamera].toArray()) {
			std::unique_ptr<CameraSession> session =
				std::make_unique<CameraSession>(cm_.get(),
								camera.toString(),
								index,
								camera.children());
			if (!session->isValid()) {
				std::cout << "Failed to create camera session" << std::endl;
				return -EINVAL;
			}

			std::cout << "Using camera " << session->camera()->id()
				  << " as cam" << index << std::endl;

			session->captureDone.connect(this, &CamApp::captureDone);

			sessions.push_back(std::move(session));
			index++;
		}
	}

	/* 3. Print camera information. */
	if (options_.isSet(OptListControls) ||
	    options_.isSet(OptListProperties) ||
	    options_.isSet(OptInfo)) {
		for (const auto &session : sessions) {
			if (options_.isSet(OptListControls))
				session->listControls();
			if (options_.isSet(OptListProperties))
				session->listProperties();
			if (options_.isSet(OptInfo))
				session->infoConfiguration();
		}
	}

	/* 4. Start capture. */
	for (const auto &session : sessions) {
		if (!session->options().isSet(OptCapture))
			continue;

		ret = session->start();
		if (ret) {
			std::cout << "Failed to start camera session" << std::endl;
			return ret;
		}

		loopUsers_++;
	}

	/* 5. Enable hotplug monitoring. */
	if (options_.isSet(OptMonitor)) {
		std::cout << "Monitoring new hotplug and unplug events" << std::endl;
		std::cout << "Press Ctrl-C to interrupt" << std::endl;

		cm_->cameraAdded.connect(this, &CamApp::cameraAdded);
		cm_->cameraRemoved.connect(this, &CamApp::cameraRemoved);

		loopUsers_++;
	}

	if (loopUsers_)
		loop_.exec();

	/* 6. Stop capture. */
	for (const auto &session : sessions) {
		if (!session->options().isSet(OptCapture))
			continue;

		session->stop();
	}

	return 0;
}

std::string CamApp::cameraName(const Camera *camera)
{
	const ControlList &props = camera->properties();
	bool addModel = true;
	std::string name;

	/*
	 * Construct the name from the camera location, model and ID. The model
	 * is only used if the location isn't present or is set to External.
	 */
	const auto &location = props.get(properties::Location);
	if (location) {
		switch (*location) {
		case properties::CameraLocationFront:
			addModel = false;
			name = "Internal front camera ";
			break;
		case properties::CameraLocationBack:
			addModel = false;
			name = "Internal back camera ";
			break;
		case properties::CameraLocationExternal:
			name = "External camera ";
			break;
		}
	}

	if (addModel) {
		/*
		 * If the camera location is not availble use the camera model
		 * to build the camera name.
		 */
		const auto &model = props.get(properties::Model);
		if (model)
			name = "'" + *model + "' ";
	}

	name += "(" + camera->id() + ")";

	return name;
}

void signalHandler([[maybe_unused]] int signal)
{
	std::cout << "Exiting" << std::endl;
	CamApp::instance()->quit();
}

int main(int argc, char **argv)
{
	CamApp app;
	int ret;

	ret = app.init(argc, argv);
	if (ret)
		return ret == -EINTR ? 0 : EXIT_FAILURE;

	struct sigaction sa = {};
	sa.sa_handler = &signalHandler;
	sigaction(SIGINT, &sa, nullptr);

	if (app.exec())
		return EXIT_FAILURE;

	return 0;
}