#include <math.h>

#include <time.h>
#include <string.h>
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>

#include "sk6812.h"
#include "logger.h"
#include "fader.h"
#include "udpproto.h"
#include "hat_spi.h"
#include "utils.h"

#define PORT 2703

#define NUM_MODULES 60
#define NUM_STRIPS 4

#define INTERVAL 0.01

struct CmdLineArgs {
	uint16_t port;
	uint32_t num_modules;
	uint32_t num_strips;
};

void wait_frame(double *nextFrame, double interval)
{
	sleep_until(*nextFrame);
	*nextFrame += interval;
}

int parse_args(int argc, char **argv, struct CmdLineArgs *args)
{
	int opt;
	unsigned long tmp_ul;
	unsigned long long tmp_ull;

	while((opt = getopt(argc, argv, "p:s:n:")) != -1) {
		switch(opt) {
			case 'p': // port
				tmp_ul = strtoul(optarg, NULL, 0);
				if(tmp_ul < 1 || tmp_ul > 65535) {
					LOG(LVL_ERR, "Port number is out of range [1..65535]: %ul", tmp_ul);
					return -1;
				}

				args->port = (uint16_t)tmp_ul;
				break;

			case 'n': // number of modules
				args->num_modules = strtoul(optarg, NULL, 0);
				break;
			case 's': // number of modules
				args->num_strips = strtoul(optarg, NULL, 0);
				break;

			default:
				return -1;
		}
	}

	return 0;
}

int main(int argc, char **argv)
{
	struct hat_spi_ctx hat_ctx;

	struct CmdLineArgs args;

	double nextFrame = get_hires_time() + INTERVAL;

	// initialize logger
	logger_init();

	// default arguments
	args.port = PORT;
	args.num_modules = NUM_MODULES;
	args.num_strips = NUM_STRIPS;

	// parse command line arguments
	if(parse_args(argc, argv, &args) == -1) {
		LOG(LVL_FATAL, "Error while parsing command line arguments!\n\n"
				"Usage: %s [-p port] [-s number_of_strips] [-n number_of_modules]\n\n", argv[0]);
		return 1;
	}

	struct fader_ctx fader_ctx[args.num_strips];
	struct sk6812_ctx ctx[args.num_strips];

	// initialize SPI interface for hat
	if(hat_spi_init(&hat_ctx) == -1) {
		LOG(LVL_FATAL, "Could not initialize SPI interface.");
		return 1;
	}

	if(hat_spi_config(&hat_ctx, args.num_modules*4) == -1) {
		LOG(LVL_FATAL, "Could not configure LED driver hat.");
		return 1;
	}

	// initialize sk6812 library
	for(int i = 0; i < args.num_strips; i++) {
		if(sk6812_init(&(ctx[i]), &hat_ctx, i, args.num_modules) == -1) {
			LOG(LVL_FATAL, "Could not initialize SK6812 library.");
			return 1;
		}
	}

	// initialise the LED fader
	for(int i = 0; i < args.num_strips; i++) {
		if(fader_init(&(fader_ctx[i]), args.num_modules, &(ctx[i])) == -1) {
			LOG(LVL_FATAL, "Could not initialize the LED fader.");
			return 1;
		}
	}

	// initialise the UDP server
	if(udpproto_init(PORT, fader_ctx, args.num_strips) == -1) {
		LOG(LVL_FATAL, "Could not initialize the UDP server.");
		return 1;
	}

	LOG(LVL_INFO, "Initialisation complete.");

	while(1) {
		udpproto_process();
		for(int i = 0; i < args.num_strips; i++) {
			fader_update(&(fader_ctx[i]));
		}
		hat_spi_flush(&hat_ctx);
		wait_frame(&nextFrame, INTERVAL);
	}

	// shut down all modules
	udpproto_shutdown();
	for(int i = 0; i < args.num_strips; i++) {
		fader_shutdown(&(fader_ctx[i]));
		sk6812_shutdown(&(ctx[i]));
	}

	return 0;
}