/* see LICENSE file for details on license */
#include <stdio.h>
#include <unistd.h>

#include "module.h"
#include "battery.h"

void populate_buffer(char *buffer, char pattern) {
	/* XXX: we assume the buffer is at least four bytes long */

	int i;
	for(i = 0; i < 3; i++) *(buffer + i) = pattern;
	*(buffer + i + 1) = '\0';
}


int battery_update(struct module *module) {
	char *filepath = BATTERY_PRE BATTERY_DIR BATTERY_CAP;
	int i;

	if (!access(filepath, F_OK) == 0) {
		populate_buffer((char *)&module->buffer, '?');
		return 1;
	}

	FILE *file = fopen(filepath, "r");
	i = fread(&module->buffer, 1, MODULE_BUFFER_LEN, file);
	module->buffer[i - 1] = '\0';

	if(ferror(file)) {
		populate_buffer((char *)&module->buffer, '!');
		return 1;
	}

	module->buffer[i] = '\0';

	return 0;
}