var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

function encode64(input) {
   var output = "";
   var chr1, chr2, chr3;
   var enc1, enc2, enc3, enc4;
   var i = 0;

   do {
      chr1 = input.charCodeAt(i++);
      chr2 = input.charCodeAt(i++);
      chr3 = input.charCodeAt(i++);

      enc1 = chr1 >> 2;
      enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
      enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
      enc4 = chr3 & 63;

      if (isNaN(chr2)) {
         enc3 = enc4 = 64;
      } else if (isNaN(chr3)) {
         enc4 = 64;
      }

      output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2) +
         keyStr.charAt(enc3) + keyStr.charAt(enc4);
   } while (i < input.length);

   return output;
}

function decode64(input) {
   var output = "";
   var chr1, chr2, chr3;
   var enc1, enc2, enc3, enc4;
   var i = 0;

   // remove all characters that are not A-Z, a-z, 0-9, +, /, or =
   input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

   do {
      enc1 = keyStr.indexOf(input.charAt(i++));
      enc2 = keyStr.indexOf(input.charAt(i++));
      enc3 = keyStr.indexOf(input.charAt(i++));
      enc4 = keyStr.indexOf(input.charAt(i++));

      chr1 = (enc1 << 2) | (enc2 >> 4);
      chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
      chr3 = ((enc3 & 3) << 6) | enc4;

      output = output + String.fromCharCode(chr1);

      if (enc3 != 64) {
         output = output + String.fromCharCode(chr2);
      }
      if (enc4 != 64) {
         output = output + String.fromCharCode(chr3);
      }
   } while (i < input.length);

   return output;
}
function encode64Han(str) {
  return encode64(escape(str))
}
function decode64Han(str) {
  return unescape(decode64(str))
}

function encodeURL(str){

    var s0, i, s, u;

    s0 = "";                // encoded str

    for (i = 0; i < str.length; i++){   // scan the source

        s = str.charAt(i);

        u = str.charCodeAt(i);          // get unicode of the char

        if (s == " "){s0 += "+";}       // SP should be converted to "+"

        else {

            if ( u == 0x2a || u == 0x2d || u == 0x2e || u == 0x5f || ((u >= 0x30) && (u <= 0x39)) || ((u >= 0x41) && (u <= 0x5a)) || ((u >= 0x61) && (u <= 0x7a))){       // check for escape

                s0 = s0 + s;            // don't escape

            }

            else {                  // escape

                if ((u >= 0x0) && (u <= 0x7f)){     // single byte format

                    s = "0"+u.toString(16);

                    s0 += "%"+ s.substr(s.length-2);

                }

                else if (u > 0x1fffff){     // quaternary byte format (extended)

                    s0 += "%" + (oxf0 + ((u & 0x1c0000) >> 18)).toString(16);

                    s0 += "%" + (0x80 + ((u & 0x3f000) >> 12)).toString(16);

                    s0 += "%" + (0x80 + ((u & 0xfc0) >> 6)).toString(16);

                    s0 += "%" + (0x80 + (u & 0x3f)).toString(16);

                }

                else if (u > 0x7ff){        // triple byte format

                    s0 += "%" + (0xe0 + ((u & 0xf000) >> 12)).toString(16);

                    s0 += "%" + (0x80 + ((u & 0xfc0) >> 6)).toString(16);

                    s0 += "%" + (0x80 + (u & 0x3f)).toString(16);

                }

                else {                      // double byte format

                    s0 += "%" + (0xc0 + ((u & 0x7c0) >> 6)).toString(16);

                    s0 += "%" + (0x80 + (u & 0x3f)).toString(16);

                }

            }

        }

    }

    return s0;

}


function decodeURL(str){

    var s0, i, j, s, ss, u, n, f;

    s0 = "";                // decoded str

    for (i = 0; i < str.length; i++){   // scan the source str

        s = str.charAt(i);

        if (s == "+"){s0 += " ";}       // "+" should be changed to SP

        else {

            if (s != "%"){s0 += s;}     // add an unescaped char

            else{               // escape sequence decoding

                u = 0;          // unicode of the character

                f = 1;          // escape flag, zero means end of this sequence

                while (true) {

                    ss = "";        // local str to parse as int

                        for (j = 0; j < 2; j++ ) {  // get two maximum hex characters for parse

                            sss = str.charAt(++i);

                            if (((sss >= "0") && (sss <= "9")) || ((sss >= "a") && (sss <= "f"))  || ((sss >= "A") && (sss <= "F"))) {

                                ss += sss;      // if hex, add the hex character

                            } else {--i; break;}    // not a hex char., exit the loop

                        }

                    n = parseInt(ss, 16);           // parse the hex str as byte

                    if (n <= 0x7f){u = n; f = 1;}   // single byte format

                    if ((n >= 0xc0) && (n <= 0xdf)){u = n & 0x1f; f = 2;}   // double byte format

                    if ((n >= 0xe0) && (n <= 0xef)){u = n & 0x0f; f = 3;}   // triple byte format

                    if ((n >= 0xf0) && (n <= 0xf7)){u = n & 0x07; f = 4;}   // quaternary byte format (extended)

                    if ((n >= 0x80) && (n <= 0xbf)){u = (u << 6) + (n & 0x3f); --f;}         // not a first, shift and add 6 lower bits

                    if (f <= 1){break;}         // end of the utf byte sequence

                    if (str.charAt(i + 1) == "%"){ i++ ;}                   // test for the next shift byte

                    else {break;}                   // abnormal, format error

                }

            s0 += String.fromCharCode(u);           // add the escaped character

            }

        }

    }

    return s0;

}