#include <stdint.h>
#include <stdlib.h>
#include "ucore/string.h"

static const char basecode[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
#define PAD '='

size_t 
uc_base64_enc(const unsigned char *data,size_t len,unsigned char *result)
{

	size_t	i = 0, j = 0;
	size_t	pad;


	while (i < len) {
		pad = 3 - (len - i);
		switch(pad) {
		case 2:
			result[j] = basecode[data[i]>>2];
			result[j+1] = basecode[(data[i] & 0x03) << 4];
			result[j+2] = PAD;
			result[j+3] = PAD;
			break;
		case 3:
			result[j  ] = basecode[data[i]>>2];
			result[j+1] = basecode[((data[i] & 0x03) << 4) | ((data[i+1] & 0xf0) >> 4)];
			result[j+2] = basecode[(data[i+1] & 0x0f) << 2];
			result[j+3] = PAD;
			break;
		default:
			result[j  ] = basecode[data[i]>>2];
			result[j+1] = basecode[((data[i] & 0x03) << 4) | ((data[i+1] & 0xf0) >> 4)];
			result[j+2] = basecode[((data[i+1] & 0x0f) << 2) | ((data[i+2] & 0xc0) >> 6)];
			result[j+3] = basecode[data[i+2] & 0x3f];
			break;
		}
		j += 4;
		i += 3;
	}

	return j;
}