#include <ncurses.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <time.h>

typedef struct {
        clock_t sec;
        clock_t msec;
} TIME;
TIME *timer;
size_t timer_size;
size_t cursor;

void die(char *msg) {
	endwin();
	printf("%s: %s\n", strerror(errno), msg);
	exit(1);
}

void export(void) {
	FILE *fp = fopen("export", "a");
	if (fp == NULL)
		die("");

	for (size_t i = 0; i < timer_size; i++)
		fprintf(fp, "%ld%ld,", timer[i].sec, timer[i].msec / 10);

	fclose(fp);
}

void add_value(clock_t sec, clock_t msec) {
	timer_size++;

	timer = realloc(timer, (1 + timer_size) * sizeof(TIME));
	if (timer == NULL)
		die("realloc returned NULL");

	timer[timer_size].sec = sec;
	timer[timer_size].msec = msec;
}

void keyboard(clock_t sec, clock_t mcsec) {
	int key = getch();
	if (key < 0)
		return;

	switch (key) {
		case ' ':
			add_value(sec, mcsec / 10000);
			cursor = timer_size;
			break;

		case 'w':
			if (cursor + 1 <= timer_size)
				cursor++;
			break;

		case 's':
			if (cursor - 1 > 0)
				cursor--;
			break;

		case 'p':
			timeout(-1);
			getch();
			timeout(0);
			clear();
			break;

		case 'e':
			endwin();
			export();
			exit(0);

		case 'q':
			endwin();
			exit(0);

		default:
			break;
	}

	clear();
}

void print_timer(void) {
	if (timer_size > 0) {
		/* Start y */
		unsigned int y = 4;
		mvprintw(y, 0, ">");

		for (size_t i = cursor; i < cursor + 10; i++) {
			if (i > timer_size)
				break;

			mvprintw(y++, 2, "(%ld) %ld.%ld", i, timer[i].sec, timer[i].msec);
		}
	}
}

int main(int argc, char **argv) {
	if (strcmp(argv[argc - 1], "start")) {
		printf("[q quit] [e export] [' ' add mark] [w/s control] [p pause]\nUse: %s start\n", argv[0]);
		return 0;
	}

	/* Init array */
	timer = malloc(sizeof(TIME));
	if (timer == NULL)
		die("malloc returned NULL");

	/* Init terminal */
	initscr();
	noecho();
	timeout(0);
	curs_set(0);

	while (1) {

		/* Microsecond */
		clock_t mcsec = clock();
		if (mcsec == -1)
			die("");

		clock_t sec = mcsec / 1000000;
		clock_t msec = (mcsec / 100000) % 10;

		mvprintw(3, 2, "%ld.%ld", sec, msec);

		print_timer();
		keyboard(sec, mcsec);

		refresh();
	}
}