// For debugging
#include<stdio.h>
#include<fcntl.h>
#include<string.h>
#include<unistd.h>
#include<stdlib.h>
#include<sys/wait.h>

/* Remember to free the returned pointer */
char* getoutput(char *command){
	size_t space = 16;
	char *output = malloc(space);
	int pipe_ends[2]; // pipefd[0] is the read end, pipefd[1] is the write end
	pipe(pipe_ends);
	pid_t pid = fork();
	if(pid) { // We're the parent
		close(pipe_ends[1]);	
		size_t position = 0;
		ssize_t readlen;
		while((readlen = read(pipe_ends[0], output + position, 16)) > 0 ){
			position += readlen;
			output = realloc(output, space + 16);
			space += 16;
		}
		output[position] = 0;	
		wait(NULL);
		return output;
	} else { // We're the child
		dup2(pipe_ends[1], 1);
		execl("/bin/sh", "sh", "-c", command, NULL);
		printf("This won't happen\n");
		exit(1);
	}
}

/* Note:  This command is specific to the formatting dmesg uses */
char *get_owl_usb(){
	char *ousb = getoutput("dmesg | grep 'Product: Meeting Owl' | cut -d : -f 1 | cut -d ']' -f 2 | cut -d ' ' -f 3 | tail -n 1");
	ousb[strlen(ousb) - 1] = 0;
	return ousb;
}

/* Note:  This command assumes that the failure will be in the last 10 lines
 * It also assumes there was no previous failure within the last 10 lines */
int failed(char *owl_usb){
	char command[128];
	sprintf(command, "dmesg  | tail -n 10 | grep %s | grep -e failed -e disconnect > /dev/null", owl_usb);
	return !system(command);
}

#define WORKING 1
#define FAILED 2

int main(){
	
/* For debugging, comment out this part and printf will still work and so will ctrl+c */
	pid_t child_pid = fork();
	if(child_pid){ // We're the parent
		return 0;
	}
//*/
	// We're the child
	int state = WORKING;
	char *owl_usb = get_owl_usb();
	while(1){
		if(state == WORKING){
			sleep(5);
			if(failed(owl_usb)){
				state = FAILED;
				system("gedit /home/seth/failed.html");	
			}
		}
		if(state == FAILED){
			sleep(60);
			owl_usb = get_owl_usb();
			if(!failed(owl_usb))
				state == WORKING;
		}
	}

	return 0;
}