// HTML 支持的数学符号
function strNumDiscode(str) {
  str = str.replace(/∀/g, '∀');
  str = str.replace(/∂/g, '∂');
  str = str.replace(/&exists;/g, '∃');
  str = str.replace(/∅/g, '∅');
  str = str.replace(/∇/g, '∇');
  str = str.replace(/∈/g, '∈');
  str = str.replace(/∉/g, '∉');
  str = str.replace(/∋/g, '∋');
  str = str.replace(/∏/g, '∏');
  str = str.replace(/∑/g, '∑');
  str = str.replace(/−/g, '−');
  str = str.replace(/∗/g, '∗');
  str = str.replace(/√/g, '√');
  str = str.replace(/∝/g, '∝');
  str = str.replace(/∞/g, '∞');
  str = str.replace(/∠/g, '∠');
  str = str.replace(/∧/g, '∧');
  str = str.replace(/∨/g, '∨');
  str = str.replace(/∩/g, '∩');
  str = str.replace(/∩/g, '∪');
  str = str.replace(/∫/g, '∫');
  str = str.replace(/∴/g, '∴');
  str = str.replace(/∼/g, '∼');
  str = str.replace(/≅/g, '≅');
  str = str.replace(/≈/g, '≈');
  str = str.replace(/≠/g, '≠');
  str = str.replace(/≤/g, '≤');
  str = str.replace(/≥/g, '≥');
  str = str.replace(/⊂/g, '⊂');
  str = str.replace(/⊃/g, '⊃');
  str = str.replace(/⊄/g, '⊄');
  str = str.replace(/⊆/g, '⊆');
  str = str.replace(/⊇/g, '⊇');
  str = str.replace(/⊕/g, '⊕');
  str = str.replace(/⊗/g, '⊗');
  str = str.replace(/⊥/g, '⊥');
  str = str.replace(/⋅/g, '⋅');
  return str;
} //HTML 支持的希腊字母


function strGreeceDiscode(str) {
  str = str.replace(/Α/g, 'Α');
  str = str.replace(/Β/g, 'Β');
  str = str.replace(/Γ/g, 'Γ');
  str = str.replace(/Δ/g, 'Δ');
  str = str.replace(/Ε/g, 'Ε');
  str = str.replace(/Ζ/g, 'Ζ');
  str = str.replace(/Η/g, 'Η');
  str = str.replace(/Θ/g, 'Θ');
  str = str.replace(/Ι/g, 'Ι');
  str = str.replace(/Κ/g, 'Κ');
  str = str.replace(/Λ/g, 'Λ');
  str = str.replace(/Μ/g, 'Μ');
  str = str.replace(/Ν/g, 'Ν');
  str = str.replace(/Ξ/g, 'Ν');
  str = str.replace(/Ο/g, 'Ο');
  str = str.replace(/Π/g, 'Π');
  str = str.replace(/Ρ/g, 'Ρ');
  str = str.replace(/Σ/g, 'Σ');
  str = str.replace(/Τ/g, 'Τ');
  str = str.replace(/Υ/g, 'Υ');
  str = str.replace(/Φ/g, 'Φ');
  str = str.replace(/Χ/g, 'Χ');
  str = str.replace(/Ψ/g, 'Ψ');
  str = str.replace(/Ω/g, 'Ω');
  str = str.replace(/α/g, 'α');
  str = str.replace(/β/g, 'β');
  str = str.replace(/γ/g, 'γ');
  str = str.replace(/δ/g, 'δ');
  str = str.replace(/ε/g, 'ε');
  str = str.replace(/ζ/g, 'ζ');
  str = str.replace(/η/g, 'η');
  str = str.replace(/θ/g, 'θ');
  str = str.replace(/ι/g, 'ι');
  str = str.replace(/κ/g, 'κ');
  str = str.replace(/λ/g, 'λ');
  str = str.replace(/μ/g, 'μ');
  str = str.replace(/ν/g, 'ν');
  str = str.replace(/ξ/g, 'ξ');
  str = str.replace(/ο/g, 'ο');
  str = str.replace(/π/g, 'π');
  str = str.replace(/ρ/g, 'ρ');
  str = str.replace(/ς/g, 'ς');
  str = str.replace(/σ/g, 'σ');
  str = str.replace(/τ/g, 'τ');
  str = str.replace(/υ/g, 'υ');
  str = str.replace(/φ/g, 'φ');
  str = str.replace(/χ/g, 'χ');
  str = str.replace(/ψ/g, 'ψ');
  str = str.replace(/ω/g, 'ω');
  str = str.replace(/ϑ/g, 'ϑ');
  str = str.replace(/ϒ/g, 'ϒ');
  str = str.replace(/ϖ/g, 'ϖ');
  str = str.replace(/·/g, '·');
  return str;
} // 


function strcharacterDiscode(str) {
  // 加入常用解析
  str = str.replace(/ /g, ' ');
  str = str.replace(/"/g, "'");
  str = str.replace(/&/g, '&'); // str = str.replace(/</g, '‹');
  // str = str.replace(/>/g, '›');

  str = str.replace(/&lt;/g, '<');
  str = str.replace(/&gt;/g, '>');
  str = str.replace(/&#8226;/g, '•');
  return str;
} // HTML 支持的其他实体


function strOtherDiscode(str) {
  str = str.replace(/&OElig;/g, 'Œ');
  str = str.replace(/&oelig;/g, 'œ');
  str = str.replace(/&Scaron;/g, 'Š');
  str = str.replace(/&scaron;/g, 'š');
  str = str.replace(/&Yuml;/g, 'Ÿ');
  str = str.replace(/&fnof;/g, 'ƒ');
  str = str.replace(/&circ;/g, 'ˆ');
  str = str.replace(/&tilde;/g, '˜');
  str = str.replace(/&ensp;/g, '');
  str = str.replace(/&emsp;/g, '');
  str = str.replace(/&thinsp;/g, '');
  str = str.replace(/&zwnj;/g, '');
  str = str.replace(/&zwj;/g, '');
  str = str.replace(/&lrm;/g, '');
  str = str.replace(/&rlm;/g, '');
  str = str.replace(/&ndash;/g, '–');
  str = str.replace(/&mdash;/g, '—');
  str = str.replace(/&lsquo;/g, '‘');
  str = str.replace(/&rsquo;/g, '’');
  str = str.replace(/&sbquo;/g, '‚');
  str = str.replace(/&ldquo;/g, '“');
  str = str.replace(/&rdquo;/g, '”');
  str = str.replace(/&bdquo;/g, '„');
  str = str.replace(/&dagger;/g, '†');
  str = str.replace(/&Dagger;/g, '‡');
  str = str.replace(/&bull;/g, '•');
  str = str.replace(/&hellip;/g, '…');
  str = str.replace(/&permil;/g, '‰');
  str = str.replace(/&prime;/g, '′');
  str = str.replace(/&Prime;/g, '″');
  str = str.replace(/&lsaquo;/g, '‹');
  str = str.replace(/&rsaquo;/g, '›');
  str = str.replace(/&oline;/g, '‾');
  str = str.replace(/&euro;/g, '€');
  str = str.replace(/&trade;/g, '™');
  str = str.replace(/&larr;/g, '←');
  str = str.replace(/&uarr;/g, '↑');
  str = str.replace(/&rarr;/g, '→');
  str = str.replace(/&darr;/g, '↓');
  str = str.replace(/&harr;/g, '↔');
  str = str.replace(/&crarr;/g, '↵');
  str = str.replace(/&lceil;/g, '⌈');
  str = str.replace(/&rceil;/g, '⌉');
  str = str.replace(/&lfloor;/g, '⌊');
  str = str.replace(/&rfloor;/g, '⌋');
  str = str.replace(/&loz;/g, '◊');
  str = str.replace(/&spades;/g, '♠');
  str = str.replace(/&clubs;/g, '♣');
  str = str.replace(/&hearts;/g, '♥');
  str = str.replace(/&diams;/g, '♦');
  str = str.replace(/&#39;/g, '\'');
  return str;
}

function strMoreDiscode(str) {
  str = str.replace(/\r\n/g, "");
  str = str.replace(/\n/g, "");
  str = str.replace(/code/g, "wxxxcode-style");
  return str;
}

function strDiscode(str) {
  str = strNumDiscode(str);
  str = strGreeceDiscode(str);
  str = strcharacterDiscode(str);
  str = strOtherDiscode(str);
  str = strMoreDiscode(str);
  return str;
}

function urlToHttpUrl(url, rep) {
  var patt1 = new RegExp("^//");
  var result = patt1.test(url);

  if (result) {
    url = rep + ":" + url;
  }

  return url;
}

module.exports = {
  strDiscode: strDiscode,
  urlToHttpUrl: urlToHttpUrl
};