// Steering Wheel Remote
//
// Douglas Thrift
//
// $Id$

#include <iostream>
#include <string>

#include <err.h>
#include <fcntl.h>
#include <sys/ioctl.h>

#include <common.hpp>
#include <fdstream.hpp>
#include <foreach.hpp>
#include <posix.hpp>
#include <regex.hpp>

struct Buttons
{
	// XXX: this is probably little endian!
	enum Mask
	{
		None = 0xfb00,
		PlayPause = 0x0101,
		Previous = 0x1010,
		Next = 0x0808,
		VolumeDown = 0x0c04,
		VolumeUp = 0x0202
	};

private:
	uint16_t buttons;

public:
	inline bool Pressed(Mask mask) const
	{
		return ((buttons ^ None) & mask) == mask;
	}

	inline operator uint16_t() const
	{
		return buttons;
	}

	friend std::istream &operator>>(std::istream &, Buttons &);
};

inline std::istream &operator>>(std::istream &input, Buttons &buttons)
{
	if (!input.ignore(3))
		return input;

	if (!input.read(reinterpret_cast<char *>(&buttons.buttons), sizeof (buttons.buttons)))
		return input;

	return input.ignore(3);
}

int Usage(const std::string &program)
{
	std::cout << _B("Usage: ") << program << _B(" [-debug] [-device=device]") << std::endl;

	return 1;
}

int main(int argc, char *argv[])
{
	bool debug(false);
	std::string device;

	{
		Pcre::RegEx devicePath(_B("^-device=(/.+)$"));
		Pcre::RegEx deviceNumber(_B("^-device=([0-9]+)$"));
		Pcre::RegEx deviceName(_B("^-device=(.+)$"));

		_forall (int, index, 1, argc)
			if (argv[index] == _B("-debug"))
				debug = true;
			else if (Pcre::RegEx::Match match = devicePath(argv[index]))
				device = match[1];
			else if (Pcre::RegEx::Match match = deviceNumber(argv[index]))
				device = _B("/dev/uhid") + match[1];
			else if (Pcre::RegEx::Match match = deviceName(argv[index]))
				device = _B("/dev/") + match[1];
			else
				return Usage(argv[0]);
	}

	if (device.empty())
		return Usage(argv[0]);

//	if (!debug)
//		Posix::CheckError(::daemon(0, 0));

	ext::ifdstream uhid(Posix::CheckError(::open(device.c_str(), O_RDONLY)));
	Buttons buttons;

	while (uhid >> buttons)
		switch (buttons)
		{
		case Buttons::None:
			break;
		default:
			if (buttons.Pressed(Buttons::PlayPause))
				std::cout << _B("PlayPause ");

			if (buttons.Pressed(Buttons::Previous))
				std::cout << _B("Previous ");

			if (buttons.Pressed(Buttons::Next))
				std::cout << _B("Next ");

			if (buttons.Pressed(Buttons::VolumeDown))
				std::cout << _B("VolumeDown ");

			if (buttons.Pressed(Buttons::VolumeUp))
				std::cout << _B("VolumeUp");

			std::cout << std::endl;
		}

	return 0;
}