#include <math.h>

#include "utils.h"

int Utils::decodeB64(QString strVal) {

    const char* val = strVal.toStdString().c_str();
    //qDebug() << "Decoding B64: " << val << "\n";
    int intTot = 0;
    int y = 0;
    for (int x = (strVal.length() - 1); x >= 0; x--) {
        int intTmp = (int) (char) ((val[x] - 64));
        if (y > 0) {
            intTmp = intTmp * (pow(64,  y));
        }
        intTot += intTmp;
        y++;
    }
    return intTot;
}

int Utils::decodeVL64(QString rawq) {
    int pos = 0;
    int v = 0;
    const char* raw = rawq.toStdString().c_str();
    bool negative = (raw[pos] & 4) == 4;
    int totalBytes = raw[pos] >> 3 & 7;
    v = raw[pos] & 3;
    pos++;
    int shiftAmount = 2;
    for (int b = 1; b < totalBytes; b++) {
        v |= (raw[pos] & 0x3f) << shiftAmount;
        shiftAmount = 2 + 6 * b;
        pos++;
    }
    if (negative) {
        v *= -1;
    }
    return v;
}

QString Utils::encodeVL64(int i) {//
    switch(i){ // first few are encoded more often then the rest, saves computationaloratories
        case 0:return QString("H");
        case 1:return QString("I");
        case 2:return QString("J");
        case 3:return QString("K");
        default:
        {
            byte* wf = new byte[7];
            memset(wf, 0, 7);
            int pos = 0;
            int startPos = pos;
            int bytes = 1;
            int negativeMask = i >= 0 ? 0 : 4;
            i = fabs(i); // secmath.h  fabs?
            wf[pos++] = (byte) (64 + (i & 3));
            for (i >>= 2; i != 0; i >>= 6) {
                bytes++;
                wf[pos++] = (byte) (64 + (i & 0x3f));
            }
            wf[startPos] = (byte) (wf[startPos] | bytes << 3 | negativeMask);
            QString vl64 = QString::fromLocal8Bit((char*) wf);
            //qDebug() << code << vl64.toLocal8Bit().toHex();
            delete[] wf;
            return vl64;
        }
    }
}