/*!
 * letiny
 * Copyright(c) 2015 Anatol Sommer <anatol@anatol.at>
 * Some code used from https://github.com/letsencrypt/boulder/tree/master/test/js
 * MPL 2.0
*/

'use strict';

var NOOP=function () {};
var log=NOOP;
var request=require('request');
var cryptoUtil=require('./crypto-util');

function Acme(privateKey) {
  this.privateKey=privateKey;
  this.nonces=[];
}

Acme.prototype.getNonce=function(url, cb) {
  var self=this;

  request.head({
    url:url,
  }, function(err, res/*, body*/) {
    if (err) {
      return cb(err);
    }
    if (res && 'replay-nonce' in res.headers) {
      log('Storing nonce: '+res.headers['replay-nonce']);
      self.nonces.push(res.headers['replay-nonce']);
      cb();
      return;
    }

    cb(new Error('Failed to get nonce for request'));
  });
};

Acme.prototype.post=function(url, body, cb) {
  var self=this, payload, jws, signed;

  if (this.nonces.length===0) {
    this.getNonce(url, function(err) {
      if (err) {
        return cb(err);
      }
      self.post(url, body, cb);
    });
    return;
  }

  log('Using nonce: '+this.nonces[0]);
  payload=JSON.stringify(body, null, 2);
  jws=cryptoUtil.generateSignature(
    this.privateKey, new Buffer(payload), this.nonces.shift()
  );
  signed=JSON.stringify(jws, null, 2);

  log('Posting to '+url);
  log(signed.green);
  log('Payload:'+payload.blue);

  return request.post({
    url:url,
    body:signed,
    encoding:null
  }, function(err, res, body) {
    var parsed;

    if (err) {
      console.error(err);
      return cb(err);
    }
    if (res) {
      log(('HTTP/1.1 '+res.statusCode).yellow);
    }

    Object.keys(res.headers).forEach(function(key) {
      var value, upcased;
      value=res.headers[key];
      upcased=key.charAt(0).toUpperCase()+key.slice(1);
      log((upcased+': '+value).yellow);
    });

    if (body && !body.toString().match(/[^\x00-\x7F]/)) {
      try {
        parsed=JSON.parse(body);
        log(JSON.stringify(parsed, null, 2).cyan);
      } catch(err) {
        log(body.toString().cyan);
      }
    }

    if ('replay-nonce' in res.headers) {
      log('Storing nonce: '+res.headers['replay-nonce']);
      self.nonces.push(res.headers['replay-nonce']);
    }

    cb(err, res, body);
  });
};

Acme.parseLink = function parseLink(link) {
  var links;
  try {
    links=link.split(',').map(function(link) {
      var parts, url, info;
      parts=link.trim().split(';');
      url=parts.shift().replace(/[<>]/g, '');
      info=parts.reduce(function(acc, p) {
        var m=p.trim().match(/(.+) *= *"(.+)"/);
        if (m) {
          acc[m[1]]=m[2];
        }
        return acc;
      }, {});
      info.url=url;
      return info;
    }).reduce(function(acc, link) {
      if ('rel' in link) {
        acc[link.rel]=link.url;
      }
      return acc;
    }, {});
    return links;
  } catch(err) {
    return null;
  }
};

module.exports = Acme;