'use strict';
require('./compat.js');

var path = require('path');
var homeRe = new RegExp("^~(\\/|\\\\|\\" + path.sep + ")");
// very basic check. Allows *.example.com.
var re = /^(\*\.)?[a-zA-Z0-9\.\-]+$/;
var punycode = require('punycode');
var dnsResolveMxAsync = require('util').promisify(require('dns').resolveMx);

module.exports.attachCertInfo = function (results) {
  var certInfo = require('cert-info').info(results.cert);

  // subject, altnames, issuedAt, expiresAt
  Object.keys(certInfo).forEach(function (key) {
    results[key] = certInfo[key];
  });

  return results;
};

module.exports.certHasDomain = function (certInfo, _domain) {
  var names = (certInfo.altnames || []).slice(0);
  names.push(certInfo.subject);
  return names.some(function (name) {
    var domain = _domain.toLowerCase();
    name = name.toLowerCase();
    if ('*.' === name.substr(0, 2)) {
      name = name.substr(2);
      domain = domain.split('.').slice(1).join('.');
    }
    return name === domain;
  });
};

module.exports.isValidDomain = function (domain) {
  if (re.test(domain)) {
    return domain;
  }

  domain = punycode.toASCII(domain);

  if (re.test(domain)) {
    return domain;
  }

  return '';
};

module.exports.merge = function (/*defaults, args*/) {
  var allDefaults = Array.prototype.slice.apply(arguments);
  var args = allDefaults.shift();
  var copy = {};

  allDefaults.forEach(function (defaults) {
    Object.keys(defaults).forEach(function (key) {
    /*
      if ('challenges' === key && copy[key] && defaults[key]) {
        Object.keys(defaults[key]).forEach(function (k) {
          copy[key][k] = defaults[key][k];
        });
      } else {
        copy[key] = defaults[key];
      }
    */
      copy[key] = defaults[key];
    });
  });

  Object.keys(args).forEach(function (key) {
    /*
    if ('challenges' === key && copy[key] && args[key]) {
        Object.keys(args[key]).forEach(function (k) {
          copy[key][k] = args[key][k];
        });
    } else {
      copy[key] = args[key];
    }
    */
    copy[key] = args[key];
  });

  return copy;
};

module.exports.tplCopy = function (copy) {
  var homedir = require('os').homedir();
  var tplKeys;

  copy.hostnameGet = function (copy) {
    return copy.subject || (copy.domains || [])[0] || copy.domain;
  };

  Object.keys(copy).forEach(function (key) {
    var newName;
    if (!/Get$/.test(key)) {
      return;
    }

    newName = key.replace(/Get$/, '');
    copy[newName] = copy[newName] || copy[key](copy);
  });

  tplKeys = Object.keys(copy);
  tplKeys.sort(function (a, b) {
    return b.length - a.length;
  });

  tplKeys.forEach(function (key) {
    if ('string' !== typeof copy[key]) {
      return;
    }

    copy[key] = copy[key].replace(homeRe, homedir + path.sep);
  });

  tplKeys.forEach(function (key) {
    if ('string' !== typeof copy[key]) {
      return;
    }

    tplKeys.forEach(function (tplname) {
      if (!copy[tplname]) {
        // what can't be templated now may be templatable later
        return;
      }
      copy[key] = copy[key].replace(':' + tplname, copy[tplname]);
    });
  });

  return copy;
};

module.exports.testEmail = function (email) {
  var parts = (email||'').split('@');
  var err;

  if (2 !== parts.length || !parts[0] || !parts[1]) {
    err = new Error("malformed email address '" + email + "'");
    err.code = 'E_EMAIL';
    return Promise.reject(err);
  }

  return dnsResolveMxAsync(parts[1]).then(function (records) {
    // records only returns when there is data
    if (!records.length) {
      throw new Error("sanity check fail: success, but no MX records returned");
    }
    return email;
  }, function (err) {
    if ('ENODATA' === err.code) {
      err = new Error("no MX records found for '" + parts[1] + "'");
      err.code = 'E_EMAIL';
      return Promise.reject(err);
    }
  });
};