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

#ifdef USE_SYSLOG
#include <syslog.h>
#endif

#include "main.h"

#ifdef USE_LIBNOTIFY
#include <libnotify/notify.h>
#endif

int run_verbose = 0;
int run_terse = 0;
int run_continuously = 0;
int interval = DEFAULT_LOG_INTERVAL;
int run_unsafe = 0;
int force_print_parameters = 0;

int warn_level = 10;

int warned = 0; /* Set if already warned */

const char * delimiter = "\n";

void print_help(void){
	printf("%s %s\n", TITLE, VERSION);
	printf("%s %s %s\n", USAGE0, PROGNAME, USAGE1);
	printf("%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n",
	       OPTIONS0, OPTIONS1, OPTIONS2, OPTIONS3, OPTIONS4,
	       OPTIONS5, OPTIONS6, OPTIONS7, OPTIONS8, OPTIONS9,
	       OPTIONS10);
}

int get_fds(FILE ** fd_now, FILE ** fd_full, const char * bat_path, const char * unit_now, const char * unit_full)
{
	size_t bat_path_len = strlen(bat_path);
	size_t unit_now_len = strlen(unit_now);
	size_t unit_full_len = strlen(unit_full);
	char * now_path = (char*)malloc(bat_path_len + unit_now_len + 1);
	char * full_path = (char*)malloc(bat_path_len + unit_full_len + 1);

	strncpy(now_path, bat_path, bat_path_len + 1);
	strncpy(full_path, bat_path, bat_path_len + 1);

	strncat(now_path, unit_now, unit_now_len);
	strncat(full_path, unit_full, unit_full_len);

	printf("Attempting to open:\n\t%s\n\t%s\n", now_path, full_path);

	(*fd_now) = fopen(now_path, "r");
	if(*fd_now == NULL){
		perror("Error opening file for current charge level");
		// if exiting here, no need to close fd_now because it is null
		return 1;
	}
	(*fd_full) = fopen(full_path, "r");
	if(*fd_full == NULL){
		perror("Error opening file for maximum charge level");
		// it just makes me feel safer, but this should be redundant
		if((*fd_now) != NULL){
			fclose(*fd_now);
		}
		return 1;
	}
	printf("Successfully found files at %p and %p\n", (void*)fd_now, (void*)fd_full);
	return 0;
}

int get_percentage
(FILE * fd_now, FILE * fd_full, double * c_now, double * c_full, double * frac, int *pct)
{
	int vals_read = fscanf(fd_now, "%lf", c_now);
	if(vals_read != 1){
		if(errno != 0){
			perror("Error reading full battery charge: ");
		} else if(vals_read == EOF){
			printf("End-of-file reached while reading current battery charge(?)");
		} else {
			printf("Invalid number of arguments (%d) returned while reading full battery charge", vals_read);
		}
		return 1;
	}
	vals_read = fscanf(fd_full, "%lf", c_full);
	if(vals_read != 1){
		if(errno != 0){
			perror("Error reading full battery charge: ");
		} else if(vals_read == EOF){
			printf("End-of-file reached while reading full battery charge(?)");
		} else {
			printf("Invalid number of arguments (%d) returned while reading full battery charge", vals_read);
		}
		return 1;
	}
	(*frac) = *c_now / *c_full;
	(*pct) = (int)((*frac) * 100);
	return 0;
}

void warn(int pct){
	if(!warned){

		printf("Battery Low\n");

#ifdef USE_SYSLOG
		syslog(LOG_WARNING, "Battery Low");
#endif
		
#ifdef USE_LIBNOTIFY
		char warnmesg[MESGLEN];
		snprintf(warnmesg, MESGLEN, "Battery is at %d percent", pct);
		notify_init(PROGNAME);
		NotifyNotification * levelwarn = notify_notification_new("Battery Low", warnmesg, "dialog-information");
		notify_notification_show(levelwarn, NULL);
		g_object_unref(G_OBJECT(levelwarn));
		notify_uninit();
#endif
	}
	warned = 1;
}

int main(int argc, char *const argv[]){

	int opt;
	while((opt = getopt(argc, argv, "vhtli:uw:p")) != -1) {
		switch(opt){
		case 'v':
			run_verbose = 1;
			break;
		case 'h':
			print_help();
			return 0;
		case 't':
			run_terse = 1;
			break;
		case 'l':
			run_continuously = 1;
			break;
		case 'i':
			interval = atoi(optarg);
			run_continuously = 1;
			break;
		case 'u':
			run_unsafe = 1;
			break;
		case 'w':
			warn_level = atoi(optarg);
			break;
		case 'p':
			force_print_parameters = 1;
			break;
		default:
			printf("Literally how could you pass an unspecified argument to this program");
		}
	}

	/**
	   Print run parameters at startup
	*/
	if(force_print_parameters) {
		if(run_terse && run_verbose){
			printf(PROGNAME " called with arguments to run both tersely and verbosely, the author legitimately cannot tell what you want her to do\n");
		} else if(run_terse) {
			printf(PROGNAME " will run tersely\n");
		} else if(run_verbose) {
			printf(PROGNAME " will run verbosely\n");
		}
		printf(PROGNAME " will poll every %d seconds\n", interval);
		if(!run_terse){
			printf(PROGNAME " will warn at %d%% battery\n", warn_level);
		}
		
		
	}
	
	if(warn_level <= 0 && !run_terse){
		fprintf(stderr, "Warn level set to %d. " PROGNAME " will not send warning on low battery.\n", warn_level);
	}

	if(interval < 15 && !run_unsafe){
		fprintf(stderr, "Update interval less than 15 seconds, refusing to run. Specify -u to override this check.\n");
		return 1;
	}

	
#ifdef USE_SYSLOG
        openlog(PROGNAME, 0, LOG_USER);
#endif
	
	FILE * fd_now;
       	FILE * fd_full;


if(get_fds(&fd_now, &fd_full, BAT_PATH, CHARGE_NOW_PATH, CHARGE_FULL_PATH)){
	printf("Charge unavailable, attempting to use energy\n");
if(get_fds(&fd_now, &fd_full, BAT_PATH, ENERGY_NOW_PATH, ENERGY_FULL_PATH)){
	printf("Could not find a charge unit that works.\n");
	exit(1);
} else {
	printf("Unit is energy");
}
}
	fflush(stdout);
	double c_now;
	double c_full;
	double frac;
	int pct;

	do{
		int rval = get_percentage(fd_now, fd_full, &c_now, &c_full, &frac, &pct);
		if (rval){
			printf("Um, problem\n");
			return 1;
		}
		if(run_verbose){
			printf("Current charge: %lf\n microampere-hours\n", c_now);
			printf("Full charge: %lf\n microampere-hours\n", c_full);
		}
		
		if(!run_terse) {
			printf("Battery percentage: ");
		}
		
		if(pct > warn_level){
			warned = 0;
		}
		
		if(pct <= warn_level && !warned){
			warn(pct);
		}
		printf("%d%s", pct, delimiter);
#ifdef USE_SYSLOG
		syslog(LOG_INFO, "%d%%%s", pct, delimiter);
#endif
		if(run_continuously){
			sleep(interval);
			errno = 0;
			rewind(fd_now);
			if(errno != 0){
				perror("Error rewinding " CHARGE_NOW_PATH);
				return 1;
			}
			rewind(fd_full); //just for the hecc of it
			if(errno != 0){
				perror("Error rewinding " CHARGE_FULL_PATH);
				return 1;
			}/*
			fclose(fd_now);
			fclose(fd_full);
			fd_now = fopen(CHARGE_NOW_PATH, "r");
			fd_full = fopen(CHARGE_FULL_PATH, "r");*/
		}
	} while (run_continuously);


#ifdef USE_SYSLOG
	closelog();
#endif
	
	return 0;
}