const wx2my = require('../wx2my');
const Behavior = require('../Behavior');
var QR = function () {
  // alignment pattern
  var adelta = [0, 11, 15, 19, 23, 27, 31, // force 1 pat
  16, 18, 20, 22, 24, 26, 28, 20, 22, 24, 24, 26, 28, 28, 22, 24, 24, 26, 26, 28, 28, 24, 24, 26, 26, 26, 28, 28, 24, 26, 26, 26, 28, 28]; // version block

  var vpat = [0xc94, 0x5bc, 0xa99, 0x4d3, 0xbf6, 0x762, 0x847, 0x60d, 0x928, 0xb78, 0x45d, 0xa17, 0x532, 0x9a6, 0x683, 0x8c9, 0x7ec, 0xec4, 0x1e1, 0xfab, 0x08e, 0xc1a, 0x33f, 0xd75, 0x250, 0x9d5, 0x6f0, 0x8ba, 0x79f, 0xb0b, 0x42e, 0xa64, 0x541, 0xc69]; // final format bits with mask: level << 3 | mask

  var fmtword = [0x77c4, 0x72f3, 0x7daa, 0x789d, 0x662f, 0x6318, 0x6c41, 0x6976, //L
  0x5412, 0x5125, 0x5e7c, 0x5b4b, 0x45f9, 0x40ce, 0x4f97, 0x4aa0, //M
  0x355f, 0x3068, 0x3f31, 0x3a06, 0x24b4, 0x2183, 0x2eda, 0x2bed, //Q
  0x1689, 0x13be, 0x1ce7, 0x19d0, 0x0762, 0x0255, 0x0d0c, 0x083b //H
  ]; // 4 per version: number of blocks 1,2; data width; ecc width

  var eccblocks = [1, 0, 19, 7, 1, 0, 16, 10, 1, 0, 13, 13, 1, 0, 9, 17, 1, 0, 34, 10, 1, 0, 28, 16, 1, 0, 22, 22, 1, 0, 16, 28, 1, 0, 55, 15, 1, 0, 44, 26, 2, 0, 17, 18, 2, 0, 13, 22, 1, 0, 80, 20, 2, 0, 32, 18, 2, 0, 24, 26, 4, 0, 9, 16, 1, 0, 108, 26, 2, 0, 43, 24, 2, 2, 15, 18, 2, 2, 11, 22, 2, 0, 68, 18, 4, 0, 27, 16, 4, 0, 19, 24, 4, 0, 15, 28, 2, 0, 78, 20, 4, 0, 31, 18, 2, 4, 14, 18, 4, 1, 13, 26, 2, 0, 97, 24, 2, 2, 38, 22, 4, 2, 18, 22, 4, 2, 14, 26, 2, 0, 116, 30, 3, 2, 36, 22, 4, 4, 16, 20, 4, 4, 12, 24, 2, 2, 68, 18, 4, 1, 43, 26, 6, 2, 19, 24, 6, 2, 15, 28, 4, 0, 81, 20, 1, 4, 50, 30, 4, 4, 22, 28, 3, 8, 12, 24, 2, 2, 92, 24, 6, 2, 36, 22, 4, 6, 20, 26, 7, 4, 14, 28, 4, 0, 107, 26, 8, 1, 37, 22, 8, 4, 20, 24, 12, 4, 11, 22, 3, 1, 115, 30, 4, 5, 40, 24, 11, 5, 16, 20, 11, 5, 12, 24, 5, 1, 87, 22, 5, 5, 41, 24, 5, 7, 24, 30, 11, 7, 12, 24, 5, 1, 98, 24, 7, 3, 45, 28, 15, 2, 19, 24, 3, 13, 15, 30, 1, 5, 107, 28, 10, 1, 46, 28, 1, 15, 22, 28, 2, 17, 14, 28, 5, 1, 120, 30, 9, 4, 43, 26, 17, 1, 22, 28, 2, 19, 14, 28, 3, 4, 113, 28, 3, 11, 44, 26, 17, 4, 21, 26, 9, 16, 13, 26, 3, 5, 107, 28, 3, 13, 41, 26, 15, 5, 24, 30, 15, 10, 15, 28, 4, 4, 116, 28, 17, 0, 42, 26, 17, 6, 22, 28, 19, 6, 16, 30, 2, 7, 111, 28, 17, 0, 46, 28, 7, 16, 24, 30, 34, 0, 13, 24, 4, 5, 121, 30, 4, 14, 47, 28, 11, 14, 24, 30, 16, 14, 15, 30, 6, 4, 117, 30, 6, 14, 45, 28, 11, 16, 24, 30, 30, 2, 16, 30, 8, 4, 106, 26, 8, 13, 47, 28, 7, 22, 24, 30, 22, 13, 15, 30, 10, 2, 114, 28, 19, 4, 46, 28, 28, 6, 22, 28, 33, 4, 16, 30, 8, 4, 122, 30, 22, 3, 45, 28, 8, 26, 23, 30, 12, 28, 15, 30, 3, 10, 117, 30, 3, 23, 45, 28, 4, 31, 24, 30, 11, 31, 15, 30, 7, 7, 116, 30, 21, 7, 45, 28, 1, 37, 23, 30, 19, 26, 15, 30, 5, 10, 115, 30, 19, 10, 47, 28, 15, 25, 24, 30, 23, 25, 15, 30, 13, 3, 115, 30, 2, 29, 46, 28, 42, 1, 24, 30, 23, 28, 15, 30, 17, 0, 115, 30, 10, 23, 46, 28, 10, 35, 24, 30, 19, 35, 15, 30, 17, 1, 115, 30, 14, 21, 46, 28, 29, 19, 24, 30, 11, 46, 15, 30, 13, 6, 115, 30, 14, 23, 46, 28, 44, 7, 24, 30, 59, 1, 16, 30, 12, 7, 121, 30, 12, 26, 47, 28, 39, 14, 24, 30, 22, 41, 15, 30, 6, 14, 121, 30, 6, 34, 47, 28, 46, 10, 24, 30, 2, 64, 15, 30, 17, 4, 122, 30, 29, 14, 46, 28, 49, 10, 24, 30, 24, 46, 15, 30, 4, 18, 122, 30, 13, 32, 46, 28, 48, 14, 24, 30, 42, 32, 15, 30, 20, 4, 117, 30, 40, 7, 47, 28, 43, 22, 24, 30, 10, 67, 15, 30, 19, 6, 118, 30, 18, 31, 47, 28, 34, 34, 24, 30, 20, 61, 15, 30]; // Galois field log table

  var glog = [0xff, 0x00, 0x01, 0x19, 0x02, 0x32, 0x1a, 0xc6, 0x03, 0xdf, 0x33, 0xee, 0x1b, 0x68, 0xc7, 0x4b, 0x04, 0x64, 0xe0, 0x0e, 0x34, 0x8d, 0xef, 0x81, 0x1c, 0xc1, 0x69, 0xf8, 0xc8, 0x08, 0x4c, 0x71, 0x05, 0x8a, 0x65, 0x2f, 0xe1, 0x24, 0x0f, 0x21, 0x35, 0x93, 0x8e, 0xda, 0xf0, 0x12, 0x82, 0x45, 0x1d, 0xb5, 0xc2, 0x7d, 0x6a, 0x27, 0xf9, 0xb9, 0xc9, 0x9a, 0x09, 0x78, 0x4d, 0xe4, 0x72, 0xa6, 0x06, 0xbf, 0x8b, 0x62, 0x66, 0xdd, 0x30, 0xfd, 0xe2, 0x98, 0x25, 0xb3, 0x10, 0x91, 0x22, 0x88, 0x36, 0xd0, 0x94, 0xce, 0x8f, 0x96, 0xdb, 0xbd, 0xf1, 0xd2, 0x13, 0x5c, 0x83, 0x38, 0x46, 0x40, 0x1e, 0x42, 0xb6, 0xa3, 0xc3, 0x48, 0x7e, 0x6e, 0x6b, 0x3a, 0x28, 0x54, 0xfa, 0x85, 0xba, 0x3d, 0xca, 0x5e, 0x9b, 0x9f, 0x0a, 0x15, 0x79, 0x2b, 0x4e, 0xd4, 0xe5, 0xac, 0x73, 0xf3, 0xa7, 0x57, 0x07, 0x70, 0xc0, 0xf7, 0x8c, 0x80, 0x63, 0x0d, 0x67, 0x4a, 0xde, 0xed, 0x31, 0xc5, 0xfe, 0x18, 0xe3, 0xa5, 0x99, 0x77, 0x26, 0xb8, 0xb4, 0x7c, 0x11, 0x44, 0x92, 0xd9, 0x23, 0x20, 0x89, 0x2e, 0x37, 0x3f, 0xd1, 0x5b, 0x95, 0xbc, 0xcf, 0xcd, 0x90, 0x87, 0x97, 0xb2, 0xdc, 0xfc, 0xbe, 0x61, 0xf2, 0x56, 0xd3, 0xab, 0x14, 0x2a, 0x5d, 0x9e, 0x84, 0x3c, 0x39, 0x53, 0x47, 0x6d, 0x41, 0xa2, 0x1f, 0x2d, 0x43, 0xd8, 0xb7, 0x7b, 0xa4, 0x76, 0xc4, 0x17, 0x49, 0xec, 0x7f, 0x0c, 0x6f, 0xf6, 0x6c, 0xa1, 0x3b, 0x52, 0x29, 0x9d, 0x55, 0xaa, 0xfb, 0x60, 0x86, 0xb1, 0xbb, 0xcc, 0x3e, 0x5a, 0xcb, 0x59, 0x5f, 0xb0, 0x9c, 0xa9, 0xa0, 0x51, 0x0b, 0xf5, 0x16, 0xeb, 0x7a, 0x75, 0x2c, 0xd7, 0x4f, 0xae, 0xd5, 0xe9, 0xe6, 0xe7, 0xad, 0xe8, 0x74, 0xd6, 0xf4, 0xea, 0xa8, 0x50, 0x58, 0xaf]; // Galios field exponent table

  var gexp = [0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1d, 0x3a, 0x74, 0xe8, 0xcd, 0x87, 0x13, 0x26, 0x4c, 0x98, 0x2d, 0x5a, 0xb4, 0x75, 0xea, 0xc9, 0x8f, 0x03, 0x06, 0x0c, 0x18, 0x30, 0x60, 0xc0, 0x9d, 0x27, 0x4e, 0x9c, 0x25, 0x4a, 0x94, 0x35, 0x6a, 0xd4, 0xb5, 0x77, 0xee, 0xc1, 0x9f, 0x23, 0x46, 0x8c, 0x05, 0x0a, 0x14, 0x28, 0x50, 0xa0, 0x5d, 0xba, 0x69, 0xd2, 0xb9, 0x6f, 0xde, 0xa1, 0x5f, 0xbe, 0x61, 0xc2, 0x99, 0x2f, 0x5e, 0xbc, 0x65, 0xca, 0x89, 0x0f, 0x1e, 0x3c, 0x78, 0xf0, 0xfd, 0xe7, 0xd3, 0xbb, 0x6b, 0xd6, 0xb1, 0x7f, 0xfe, 0xe1, 0xdf, 0xa3, 0x5b, 0xb6, 0x71, 0xe2, 0xd9, 0xaf, 0x43, 0x86, 0x11, 0x22, 0x44, 0x88, 0x0d, 0x1a, 0x34, 0x68, 0xd0, 0xbd, 0x67, 0xce, 0x81, 0x1f, 0x3e, 0x7c, 0xf8, 0xed, 0xc7, 0x93, 0x3b, 0x76, 0xec, 0xc5, 0x97, 0x33, 0x66, 0xcc, 0x85, 0x17, 0x2e, 0x5c, 0xb8, 0x6d, 0xda, 0xa9, 0x4f, 0x9e, 0x21, 0x42, 0x84, 0x15, 0x2a, 0x54, 0xa8, 0x4d, 0x9a, 0x29, 0x52, 0xa4, 0x55, 0xaa, 0x49, 0x92, 0x39, 0x72, 0xe4, 0xd5, 0xb7, 0x73, 0xe6, 0xd1, 0xbf, 0x63, 0xc6, 0x91, 0x3f, 0x7e, 0xfc, 0xe5, 0xd7, 0xb3, 0x7b, 0xf6, 0xf1, 0xff, 0xe3, 0xdb, 0xab, 0x4b, 0x96, 0x31, 0x62, 0xc4, 0x95, 0x37, 0x6e, 0xdc, 0xa5, 0x57, 0xae, 0x41, 0x82, 0x19, 0x32, 0x64, 0xc8, 0x8d, 0x07, 0x0e, 0x1c, 0x38, 0x70, 0xe0, 0xdd, 0xa7, 0x53, 0xa6, 0x51, 0xa2, 0x59, 0xb2, 0x79, 0xf2, 0xf9, 0xef, 0xc3, 0x9b, 0x2b, 0x56, 0xac, 0x45, 0x8a, 0x09, 0x12, 0x24, 0x48, 0x90, 0x3d, 0x7a, 0xf4, 0xf5, 0xf7, 0xf3, 0xfb, 0xeb, 0xcb, 0x8b, 0x0b, 0x16, 0x2c, 0x58, 0xb0, 0x7d, 0xfa, 0xe9, 0xcf, 0x83, 0x1b, 0x36, 0x6c, 0xd8, 0xad, 0x47, 0x8e, 0x00]; // Working buffers:
  // data input and ecc append, image working buffer, fixed part of image, run lengths for badness

  var strinbuf = [],
      eccbuf = [],
      qrframe = [],
      framask = [],
      rlens = []; // Control values - width is based on version, last 4 are from table.

  var version, width, neccblk1, neccblk2, datablkw, eccblkwid;
  var ecclevel = 2; // set bit to indicate cell in qrframe is immutable.  symmetric around diagonal

  function setmask(x, y) {
    var bt;

    if (x > y) {
      bt = x;
      x = y;
      y = bt;
    } // y*y = 1+3+5...


    bt = y;
    bt *= y;
    bt += y;
    bt >>= 1;
    bt += x;
    framask[bt] = 1;
  } // enter alignment pattern - black to qrframe, white to mask (later black frame merged to mask)


  function putalign(x, y) {
    var j;
    qrframe[x + width * y] = 1;

    for (j = -2; j < 2; j++) {
      qrframe[x + j + width * (y - 2)] = 1;
      qrframe[x - 2 + width * (y + j + 1)] = 1;
      qrframe[x + 2 + width * (y + j)] = 1;
      qrframe[x + j + 1 + width * (y + 2)] = 1;
    }

    for (j = 0; j < 2; j++) {
      setmask(x - 1, y + j);
      setmask(x + 1, y - j);
      setmask(x - j, y - 1);
      setmask(x + j, y + 1);
    }
  } //========================================================================
  // Reed Solomon error correction
  // exponentiation mod N


  function modnn(x) {
    while (x >= 255) {
      x -= 255;
      x = (x >> 8) + (x & 255);
    }

    return x;
  }

  var genpoly = []; // Calculate and append ECC data to data block.  Block is in strinbuf, indexes to buffers given.

  function appendrs(data, dlen, ecbuf, eclen) {
    var i, j, fb;

    for (i = 0; i < eclen; i++) strinbuf[ecbuf + i] = 0;

    for (i = 0; i < dlen; i++) {
      fb = glog[strinbuf[data + i] ^ strinbuf[ecbuf]];
      if (fb != 255)
        /* fb term is non-zero */
        for (j = 1; j < eclen; j++) strinbuf[ecbuf + j - 1] = strinbuf[ecbuf + j] ^ gexp[modnn(fb + genpoly[eclen - j])];else for (j = ecbuf; j < ecbuf + eclen; j++) strinbuf[j] = strinbuf[j + 1];
      strinbuf[ecbuf + eclen - 1] = fb == 255 ? 0 : gexp[modnn(fb + genpoly[0])];
    }
  } //========================================================================
  // Frame data insert following the path rules
  // check mask - since symmetrical use half.


  function ismasked(x, y) {
    var bt;

    if (x > y) {
      bt = x;
      x = y;
      y = bt;
    }

    bt = y;
    bt += y * y;
    bt >>= 1;
    bt += x;
    return framask[bt];
  } //========================================================================
  //  Apply the selected mask out of the 8.


  function applymask(m) {
    var x, y, r3x, r3y;

    switch (m) {
      case 0:
        for (y = 0; y < width; y++) for (x = 0; x < width; x++) if (!(x + y & 1) && !ismasked(x, y)) qrframe[x + y * width] ^= 1;

        break;

      case 1:
        for (y = 0; y < width; y++) for (x = 0; x < width; x++) if (!(y & 1) && !ismasked(x, y)) qrframe[x + y * width] ^= 1;

        break;

      case 2:
        for (y = 0; y < width; y++) for (r3x = 0, x = 0; x < width; x++, r3x++) {
          if (r3x == 3) r3x = 0;
          if (!r3x && !ismasked(x, y)) qrframe[x + y * width] ^= 1;
        }

        break;

      case 3:
        for (r3y = 0, y = 0; y < width; y++, r3y++) {
          if (r3y == 3) r3y = 0;

          for (r3x = r3y, x = 0; x < width; x++, r3x++) {
            if (r3x == 3) r3x = 0;
            if (!r3x && !ismasked(x, y)) qrframe[x + y * width] ^= 1;
          }
        }

        break;

      case 4:
        for (y = 0; y < width; y++) for (r3x = 0, r3y = y >> 1 & 1, x = 0; x < width; x++, r3x++) {
          if (r3x == 3) {
            r3x = 0;
            r3y = !r3y;
          }

          if (!r3y && !ismasked(x, y)) qrframe[x + y * width] ^= 1;
        }

        break;

      case 5:
        for (r3y = 0, y = 0; y < width; y++, r3y++) {
          if (r3y == 3) r3y = 0;

          for (r3x = 0, x = 0; x < width; x++, r3x++) {
            if (r3x == 3) r3x = 0;
            if (!((x & y & 1) + !(!r3x | !r3y)) && !ismasked(x, y)) qrframe[x + y * width] ^= 1;
          }
        }

        break;

      case 6:
        for (r3y = 0, y = 0; y < width; y++, r3y++) {
          if (r3y == 3) r3y = 0;

          for (r3x = 0, x = 0; x < width; x++, r3x++) {
            if (r3x == 3) r3x = 0;
            if (!((x & y & 1) + (r3x && r3x == r3y) & 1) && !ismasked(x, y)) qrframe[x + y * width] ^= 1;
          }
        }

        break;

      case 7:
        for (r3y = 0, y = 0; y < width; y++, r3y++) {
          if (r3y == 3) r3y = 0;

          for (r3x = 0, x = 0; x < width; x++, r3x++) {
            if (r3x == 3) r3x = 0;
            if (!((r3x && r3x == r3y) + (x + y & 1) & 1) && !ismasked(x, y)) qrframe[x + y * width] ^= 1;
          }
        }

        break;
    }

    return;
  } // Badness coefficients.


  var N1 = 3,
      N2 = 3,
      N3 = 40,
      N4 = 10; // Using the table of the length of each run, calculate the amount of bad image 
  // - long runs or those that look like finders; called twice, once each for X and Y

  function badruns(length) {
    var i;
    var runsbad = 0;

    for (i = 0; i <= length; i++) if (rlens[i] >= 5) runsbad += N1 + rlens[i] - 5; // BwBBBwB as in finder


    for (i = 3; i < length - 1; i += 2) if (rlens[i - 2] == rlens[i + 2] && rlens[i + 2] == rlens[i - 1] && rlens[i - 1] == rlens[i + 1] && rlens[i - 1] * 3 == rlens[i] // white around the black pattern? Not part of spec
    && (rlens[i - 3] == 0 // beginning
    || i + 3 > length // end
    || rlens[i - 3] * 3 >= rlens[i] * 4 || rlens[i + 3] * 3 >= rlens[i] * 4)) runsbad += N3;

    return runsbad;
  } // Calculate how bad the masked image is - blocks, imbalance, runs, or finders.


  function badcheck() {
    var x, y, h, b, b1;
    var thisbad = 0;
    var bw = 0; // blocks of same color.

    for (y = 0; y < width - 1; y++) for (x = 0; x < width - 1; x++) if (qrframe[x + width * y] && qrframe[x + 1 + width * y] && qrframe[x + width * (y + 1)] && qrframe[x + 1 + width * (y + 1)] || // all black
    !(qrframe[x + width * y] || qrframe[x + 1 + width * y] || qrframe[x + width * (y + 1)] || qrframe[x + 1 + width * (y + 1)])) // all white
      thisbad += N2; // X runs


    for (y = 0; y < width; y++) {
      rlens[0] = 0;

      for (h = b = x = 0; x < width; x++) {
        if ((b1 = qrframe[x + width * y]) == b) rlens[h]++;else rlens[++h] = 1;
        b = b1;
        bw += b ? 1 : -1;
      }

      thisbad += badruns(h);
    } // black/white imbalance


    if (bw < 0) bw = -bw;
    var big = bw;
    var count = 0;
    big += big << 2;
    big <<= 1;

    while (big > width * width) big -= width * width, count++;

    thisbad += count * N4; // Y runs

    for (x = 0; x < width; x++) {
      rlens[0] = 0;

      for (h = b = y = 0; y < width; y++) {
        if ((b1 = qrframe[x + width * y]) == b) rlens[h]++;else rlens[++h] = 1;
        b = b1;
      }

      thisbad += badruns(h);
    }

    return thisbad;
  }

  function genframe(instring) {
    var x, y, k, t, v, i, j, m; // find the smallest version that fits the string

    t = instring.length;
    version = 0;

    do {
      version++;
      k = (ecclevel - 1) * 4 + (version - 1) * 16;
      neccblk1 = eccblocks[k++];
      neccblk2 = eccblocks[k++];
      datablkw = eccblocks[k++];
      eccblkwid = eccblocks[k];
      k = datablkw * (neccblk1 + neccblk2) + neccblk2 - 3 + (version <= 9);
      if (t <= k) break;
    } while (version < 40); // FIXME - insure that it fits insted of being truncated


    width = 17 + 4 * version; // allocate, clear and setup data structures

    v = datablkw + (datablkw + eccblkwid) * (neccblk1 + neccblk2) + neccblk2;

    for (t = 0; t < v; t++) eccbuf[t] = 0;

    strinbuf = instring.slice(0);

    for (t = 0; t < width * width; t++) qrframe[t] = 0;

    for (t = 0; t < (width * (width + 1) + 1) / 2; t++) framask[t] = 0; // insert finders - black to frame, white to mask


    for (t = 0; t < 3; t++) {
      k = 0;
      y = 0;
      if (t == 1) k = width - 7;
      if (t == 2) y = width - 7;
      qrframe[y + 3 + width * (k + 3)] = 1;

      for (x = 0; x < 6; x++) {
        qrframe[y + x + width * k] = 1;
        qrframe[y + width * (k + x + 1)] = 1;
        qrframe[y + 6 + width * (k + x)] = 1;
        qrframe[y + x + 1 + width * (k + 6)] = 1;
      }

      for (x = 1; x < 5; x++) {
        setmask(y + x, k + 1);
        setmask(y + 1, k + x + 1);
        setmask(y + 5, k + x);
        setmask(y + x + 1, k + 5);
      }

      for (x = 2; x < 4; x++) {
        qrframe[y + x + width * (k + 2)] = 1;
        qrframe[y + 2 + width * (k + x + 1)] = 1;
        qrframe[y + 4 + width * (k + x)] = 1;
        qrframe[y + x + 1 + width * (k + 4)] = 1;
      }
    } // alignment blocks


    if (version > 1) {
      t = adelta[version];
      y = width - 7;

      for (;;) {
        x = width - 7;

        while (x > t - 3) {
          putalign(x, y);
          if (x < t) break;
          x -= t;
        }

        if (y <= t + 9) break;
        y -= t;
        putalign(6, y);
        putalign(y, 6);
      }
    } // single black


    qrframe[8 + width * (width - 8)] = 1; // timing gap - mask only

    for (y = 0; y < 7; y++) {
      setmask(7, y);
      setmask(width - 8, y);
      setmask(7, y + width - 7);
    }

    for (x = 0; x < 8; x++) {
      setmask(x, 7);
      setmask(x + width - 8, 7);
      setmask(x, width - 8);
    } // reserve mask-format area


    for (x = 0; x < 9; x++) setmask(x, 8);

    for (x = 0; x < 8; x++) {
      setmask(x + width - 8, 8);
      setmask(8, x);
    }

    for (y = 0; y < 7; y++) setmask(8, y + width - 7); // timing row/col


    for (x = 0; x < width - 14; x++) if (x & 1) {
      setmask(8 + x, 6);
      setmask(6, 8 + x);
    } else {
      qrframe[8 + x + width * 6] = 1;
      qrframe[6 + width * (8 + x)] = 1;
    } // version block


    if (version > 6) {
      t = vpat[version - 7];
      k = 17;

      for (x = 0; x < 6; x++) for (y = 0; y < 3; y++, k--) if (1 & (k > 11 ? version >> k - 12 : t >> k)) {
        qrframe[5 - x + width * (2 - y + width - 11)] = 1;
        qrframe[2 - y + width - 11 + width * (5 - x)] = 1;
      } else {
        setmask(5 - x, 2 - y + width - 11);
        setmask(2 - y + width - 11, 5 - x);
      }
    } // sync mask bits - only set above for white spaces, so add in black bits


    for (y = 0; y < width; y++) for (x = 0; x <= y; x++) if (qrframe[x + width * y]) setmask(x, y); // convert string to bitstream
    // 8 bit data to QR-coded 8 bit data (numeric or alphanum, or kanji not supported)


    v = strinbuf.length; // string to array

    for (i = 0; i < v; i++) eccbuf[i] = strinbuf.charCodeAt(i);

    strinbuf = eccbuf.slice(0); // calculate max string length

    x = datablkw * (neccblk1 + neccblk2) + neccblk2;

    if (v >= x - 2) {
      v = x - 2;
      if (version > 9) v--;
    } // shift and repack to insert length prefix


    i = v;

    if (version > 9) {
      strinbuf[i + 2] = 0;
      strinbuf[i + 3] = 0;

      while (i--) {
        t = strinbuf[i];
        strinbuf[i + 3] |= 255 & t << 4;
        strinbuf[i + 2] = t >> 4;
      }

      strinbuf[2] |= 255 & v << 4;
      strinbuf[1] = v >> 4;
      strinbuf[0] = 0x40 | v >> 12;
    } else {
      strinbuf[i + 1] = 0;
      strinbuf[i + 2] = 0;

      while (i--) {
        t = strinbuf[i];
        strinbuf[i + 2] |= 255 & t << 4;
        strinbuf[i + 1] = t >> 4;
      }

      strinbuf[1] |= 255 & v << 4;
      strinbuf[0] = 0x40 | v >> 4;
    } // fill to end with pad pattern


    i = v + 3 - (version < 10);

    while (i < x) {
      strinbuf[i++] = 0xec; // buffer has room    if (i == x)      break;

      strinbuf[i++] = 0x11;
    } // calculate and append ECC
    // calculate generator polynomial


    genpoly[0] = 1;

    for (i = 0; i < eccblkwid; i++) {
      genpoly[i + 1] = 1;

      for (j = i; j > 0; j--) genpoly[j] = genpoly[j] ? genpoly[j - 1] ^ gexp[modnn(glog[genpoly[j]] + i)] : genpoly[j - 1];

      genpoly[0] = gexp[modnn(glog[genpoly[0]] + i)];
    }

    for (i = 0; i <= eccblkwid; i++) genpoly[i] = glog[genpoly[i]]; // use logs for genpoly[] to save calc step
    // append ecc to data buffer


    k = x;
    y = 0;

    for (i = 0; i < neccblk1; i++) {
      appendrs(y, datablkw, k, eccblkwid);
      y += datablkw;
      k += eccblkwid;
    }

    for (i = 0; i < neccblk2; i++) {
      appendrs(y, datablkw + 1, k, eccblkwid);
      y += datablkw + 1;
      k += eccblkwid;
    } // interleave blocks


    y = 0;

    for (i = 0; i < datablkw; i++) {
      for (j = 0; j < neccblk1; j++) eccbuf[y++] = strinbuf[i + j * datablkw];

      for (j = 0; j < neccblk2; j++) eccbuf[y++] = strinbuf[neccblk1 * datablkw + i + j * (datablkw + 1)];
    }

    for (j = 0; j < neccblk2; j++) eccbuf[y++] = strinbuf[neccblk1 * datablkw + i + j * (datablkw + 1)];

    for (i = 0; i < eccblkwid; i++) for (j = 0; j < neccblk1 + neccblk2; j++) eccbuf[y++] = strinbuf[x + i + j * eccblkwid];

    strinbuf = eccbuf; // pack bits into frame avoiding masked area.

    x = y = width - 1;
    k = v = 1; // up, minus

    /* inteleaved data and ecc codes */

    m = (datablkw + eccblkwid) * (neccblk1 + neccblk2) + neccblk2;

    for (i = 0; i < m; i++) {
      t = strinbuf[i];

      for (j = 0; j < 8; j++, t <<= 1) {
        if (0x80 & t) qrframe[x + width * y] = 1;

        do {
          // find next fill position
          if (v) x--;else {
            x++;

            if (k) {
              if (y != 0) y--;else {
                x -= 2;
                k = !k;

                if (x == 6) {
                  x--;
                  y = 9;
                }
              }
            } else {
              if (y != width - 1) y++;else {
                x -= 2;
                k = !k;

                if (x == 6) {
                  x--;
                  y -= 8;
                }
              }
            }
          }
          v = !v;
        } while (ismasked(x, y));
      }
    } // save pre-mask copy of frame


    strinbuf = qrframe.slice(0);
    t = 0; // best

    y = 30000; // demerit
    // for instead of while since in original arduino code
    // if an early mask was "good enough" it wouldn't try for a better one
    // since they get more complex and take longer.

    for (k = 0; k < 8; k++) {
      applymask(k); // returns black-white imbalance

      x = badcheck();

      if (x < y) {
        // current mask better than previous best?
        y = x;
        t = k;
      }

      if (t == 7) break; // don't increment i to a void redoing mask

      qrframe = strinbuf.slice(0); // reset for next pass
    }

    if (t != k) // redo best mask - none good enough, last wasn't t
      applymask(t); // add in final mask/ecclevel bytes

    y = fmtword[t + (ecclevel - 1 << 3)]; // low byte

    for (k = 0; k < 8; k++, y >>= 1) if (y & 1) {
      qrframe[width - 1 - k + width * 8] = 1;
      if (k < 6) qrframe[8 + width * k] = 1;else qrframe[8 + width * (k + 1)] = 1;
    } // high byte


    for (k = 0; k < 7; k++, y >>= 1) if (y & 1) {
      qrframe[8 + width * (width - 7 + k)] = 1;
      if (k) qrframe[6 - k + width * 8] = 1;else qrframe[7 + width * 8] = 1;
    } // return image


    return qrframe;
  }

  var _canvas = null,
      _size = null;
  var api = {
    get ecclevel() {
      return ecclevel;
    },

    set ecclevel(val) {
      ecclevel = val;
    },

    get size() {
      return _size;
    },

    set size(val) {
      _size = val;
    },

    get canvas() {
      return _canvas;
    },

    set canvas(el) {
      _canvas = el;
    },

    getFrame: function (string) {
      return genframe(string);
    },
    draw: function (string, canvas, size, ecc) {
      ecclevel = ecc || ecclevel;
      canvas = canvas || _canvas;

      if (!canvas) {
        console.warn('No canvas provided to draw QR code in!');
        return;
      }

      size = size || _size || Math.min(canvas.width, canvas.height);
      var frame = genframe(string),
          ctx = canvas.ctx,
          px = Math.round(size / (width + 8));
      var roundedSize = px * (width + 8),
          offset = Math.floor((size - roundedSize) / 2);
      size = roundedSize;
      ctx.clearRect(0, 0, canvas.width, canvas.height);
      ctx.setFillStyle('#000000');

      for (var i = 0; i < width; i++) {
        for (var j = 0; j < width; j++) {
          if (frame[j * width + i]) {
            ctx.fillRect(px * (4 + i) + offset, px * (4 + j) + offset, px, px);
          }
        }
      }

      ctx.draw();
    }
  };
  module.exports = {
    api: api
  };
}();