#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include "battery.h"

#define stub() \
	printf("%s: i'm a stub! fixme!\n",__func__)

#define panic(pmsg) \
	fprintf(stderr,pmsg), fflush(NULL), exit(EXIT_FAILURE)

#define ignore()

typedef struct battStatus {
	unsigned int	present	:1;
	unsigned int	charging:1;		// 1 if battery is charging
	unsigned int	charged:1;		// 1 if full
	unsigned int	ac;				// 1 if AC is connected
	int				rate;			// in mW
	unsigned int	capacity;		// in mWh
	int				voltage;		// mV
}battStatus_t;

#define BATT_STATE_FILE	"/proc/acpi/battery/BAT0/state"
#define BUF_SIZE 64

static battStatus_t *battery;

static void battStatusUpdate (void){
	extern struct battStatus *battery;
	static FILE *f;
	static char buf[BUF_SIZE];
	char	*str,*str1,*str2;

	int n,t;
	
	if(!f){
		if ( !(f=fopen(BATT_STATE_FILE,"r")) ){
			perror("error reading battery state");
			fflush(NULL);
			exit(EXIT_FAILURE);
		}
	}

	rewind(f);
	n=0;
	while ( !fgets(buf,BUF_SIZE,f) ){
		t=0;
		str=str1=str2=NULL;
		static char d[8]=":";		// set the delimiter to ":" as the first string is closed by that
		while ( !(str=strtok(buf,d)) ){
				strcpy(d," \t\n");			// the second token is delimited by whitespace
				switch (++t){
					case 1:
						str1=str;
						break;
					case 2:
						str2=str;
						break;
					default:
						panic("tokenization");
				}
		} // while() tokenizer
		if ( !strcmp(str1,"present") ){
			if ( !(strcmp(str2,"yes")) )
				battery->present=1;
			else if ( !(strcmp(str2,"no")) )
				battery->present=0;
			else
				panic("Unknown batery state!");
		} else if ( !strcmp(str1,"capacity state") ){
			stub();
		} else if ( !strcmp(str1,"charging state") ){
			stub();
		} else if ( !strcmp(str1,"present rate") ){
			stub();
		} else if ( !strcmp(str1,"remaining capacity") ){
			stub();
		} else if ( !strcmp(str1,"present voltage") ){
			stub();
		} else {	
			ignore();				// here only to anticipate that we _really_ ignore it :)
		}



	} // while() sor olvaso

	if ( !feof(f) ){ // nem file vege miatt allt meg a while
		panic("nem file vége, értelmes hiba helye");
	}
}