#include <stdio.h> 
#include <stdlib.h>
#include <unistd.h>
#include <time.h>

#define MAX_MSG_LEN 100
#define LEN(a)  (sizeof(a) / sizeof(a[0]))

typedef struct {
	unsigned int t;
	char *msg;
} Timers;

static Timers timers[] = {
	/* timer(s)  comment */
	{     1500,  "Time to start working!"},
	{      300,  "Time to start resting!"},
	{     1500,  "Time to start working!"},
	{      300,  "Time to start resting!"},
	{     1500,  "Time to start working!"},
	{      300,  "Time to start resting!"},
	{     1500,  "Time to start working!"},
	{      900,  "Time to take a longer rest!"   },
};

void spawn(char *argv[]){ 
	if (fork() == 0) {
		// we need to fork the process so that 
		// when we exit the sent screen
		// this program continues.
		setsid();
		execvp(argv[0], argv);
		perror(" failed");
		exit(0);
	}
}

void print_time_now(){
    time_t timer;
    char buffer[26];
    struct tm* tm_info;

    timer = time(NULL);
    tm_info = localtime(&timer);

    strftime(buffer, 26, "%Y-%m-%d %H:%M:%S", tm_info);
    fprintf(stderr, "%s", buffer);

}

void display_message(char *msg){
		char sh_command[MAX_MSG_LEN];
		snprintf(sh_command, MAX_MSG_LEN, "echo '%s' | sent", msg); // NOLINT: We are being carefull here by considering MAX_MSG_LEN explicitly.
    printf("%s", sh_command);
		char *spawn_args[] = {
			"/bin/sh",
			"-c",
			sh_command,
			NULL
		};
		spawn(spawn_args);
		print_time_now();
		fprintf(stderr, " | %s\n", msg);
}

int main(int argc, char *argv[]){
	for(int i=0; ; i = (i+1) % LEN(timers)){
		display_message(timers[i].msg);
		sleep(timers[i].t);
	}
}