/* jsMiner.js - A Javascript Bitcoin miner */
/* version 1.1 - 5/24/2011                 */
/*                                         */
/* Copyright 2011, see LICENSE for details */
/* https://github.com/jwhitehorn/jsMiner   */
/*******************************************/

if (typeof(jsMiner) == 'undefined')
  var jsMiner = {};

jsMiner.Util = {
  hex_to_uint32_array: function(hex) {
    var arr = [];
    for (var i = 0, l = hex.length; i < l; i += 8) {
      arr.push(parseInt(hex.substring(i, i+8), 16));
    }
    return arr;
  },
  
  uint32_array_to_hex: function(arr) {
    var hex = '';
    for (var i = 0; i < arr.length; i++) {
      hex += jsMiner.Util.byte_to_hex(arr[i] >>> 24);
      hex += jsMiner.Util.byte_to_hex(arr[i] >>> 16);
      hex += jsMiner.Util.byte_to_hex(arr[i] >>>  8);
      hex += jsMiner.Util.byte_to_hex(arr[i]       );
    }
    return hex;
  },
  
  byte_to_hex: function(b) {
    var tab = '0123456789abcdef';
    b = b & 0xff;
    return tab.charAt(b / 16) +
           tab.charAt(b % 16);
  },

  reverseBytesInWord: function(w) {
    return ((w <<  24) & 0xff000000) |
           ((w <<   8) & 0x00ff0000) |
           ((w >>>  8) & 0x0000ff00) |
           ((w >>> 24) & 0x000000ff);
  },
  
  reverseBytesInWords: function(words) {
    var reversed = [];
    for(var i = 0; i < words.length; i++)
      reversed.push(jsMiner.Util.reverseBytesInWord(words[i]));
    return reversed;
  },

  fromPoolString: function(hex) {
    return jsMiner.Util.reverseBytesInWords(jsMiner.Util.hex_to_uint32_array(hex));
  },
  
  toPoolString: function(data) {
    return jsMiner.Util.uint32_array_to_hex(jsMiner.Util.reverseBytesInWords(data));
  }
};

var module;
module = module || {};
module.exports = jsMiner.Util;

Sha256 = function(init, data) {
  
  var K = [0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
           0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
           0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
           0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
           0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
           0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
           0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
           0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2];
  
  var H = [0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19];
  
  var add = function (x, y) {
    var lsw = (x & 0xFFFF) + (y & 0xFFFF);
    var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
    return (msw << 16) | (lsw & 0xFFFF);
  };

  var add_all = function() {
    var sum = arguments[0];
    for (var i = 1; i < arguments.length; i++)
      sum = add(sum, arguments[i]);
    return sum;
  };
  
  var set_state = function(target, source) {
    for (var i = 0; i < 8; i++)
      target[i] = source[i];
  };
  
  var extend_work = function(work, w) {
    for (var i = 0; i < 16; i++)
      work[i] = w[i];
    w = work;
    for (var i = 16; i < 64; i++) {
      var s0 = rotr(w[i - 15],  7) ^ rotr(w[i - 15], 18) ^ shr(w[i - 15],  3);
      var s1 = rotr(w[i -  2], 17) ^ rotr(w[i -  2], 19) ^ shr(w[i -  2], 10);
      w[i] = add_all(w[i-16], s0, w[i-7], s1);
    }
    return w;
  };
  
  var rotr = function(x, n) {
    return (x >>> n) | (x << (32 - n));
  };
  
  var shr = function(x, n) {
    return (x >>> n);
  };
  
  this.state = [0,0,0,0,0,0,0,0];
  set_state(this.state, H);
  
  this.work = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
               0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
               0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
               0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
  
  this.hex = function() {
    return jsMiner.Util.uint32_array_to_hex(this.state);
  };

  this.reset = function() {
    set_state(this.state, H);
    return this;
  };
  
  this.update = function(init, data) {
    if (!data) { data = init; init = null; }
    if (typeof(init) == 'string')
      init = jsMiner.Util.hex_to_uint32_array(init);
    if (init) set_state(this.state, init);
    if (typeof(data) == 'string')
      data = jsMiner.Util.hex_to_uint32_array(data);

    var w = extend_work(this.work, data);
    var s = this.state;
    var a = s[0], b = s[1], c = s[2], d = s[3],
        e = s[4], f = s[5], g = s[6], h = s[7];
    for (var i = 0; i < 64; i++) {
      var s0 = rotr(a, 2) ^ rotr(a, 13) ^ rotr(a, 22);
      var maj = (a & b) ^ (a & c) ^ (b & c);
      var t2 = add(s0, maj);
      var s1 = rotr(e, 6) ^ rotr(e, 11) ^ rotr(e, 25);
      var ch = (e & f) ^ ((~e) & g);
      var t1 = add_all(h, s1, ch, K[i], w[i]);
      h = g; g = f; f = e;
      e = add(d, t1);
      d = c; c = b; b = a;
      a = add(t1, t2);
    }
    s[0] = add(s[0], a);
    s[1] = add(s[1], b);
    s[2] = add(s[2], c);
    s[3] = add(s[3], d);
    s[4] = add(s[4], e);
    s[5] = add(s[5], f);
    s[6] = add(s[6], g);
    s[7] = add(s[7], h);
    return this;
  };
  
  if (init) this.update(init, data);
};

var module;
module = module || {};
module.exports = Sha256;

jsMiner.engine = function(options){
  this.publisherId = "";
  this.siteId = "";
  this.delayBetweenNonce = 30;
  this.sha = new Sha256();
  this.hashRate = 0;
  this.workerRunning = false;
  this.forceUIThread = false;
  this.autoStart = true;
  this.workerTimeout = 30;
  
  if(options){
    if (options.hasOwnProperty("clientId"))
      this.clientId = options.clientId;
    if (options.hasOwnProperty("siteId"))
      this.siteId = options.siteId;
    if (options.hasOwnProperty("delay"))
      this.delayBetweenNonce = options.delay;
    if (options.hasOwnProperty("forceUIThread"))
      this.forceUIThread = options.forceUIThread;
    if (options.hasOwnProperty("autoStart"))
      this.autoStart = options.autoStart;
    if (options.hasOwnProperty("workerTimeout"))
      this.workerTimeout = options.workerTimeout;
  }
    
  this.loadMoreWork = function(result){
    var url = "/work?client_id=" + this.clientId;
    if(this.siteId != ""){
	  url = url + "&site_id=" + this.siteId;
    }
    if(this.hashRate > 0){
      url = url + "&hash_rate=" + this.hashRate + "&hash_count=" + (this.hashRate * 1000 * this.workerTimeout);
    }
    var me = this;
    var httpRequest;
    if(window.XDomainRequest){ //IE8+
      httpRequest = new XDomainRequest();
      httpRequest.onload = function(response){
        me.handleGetWorkResponse(httpRequest.responseText);
      };
    }else if (window.XMLHttpRequest) { // Everybody else
      httpRequest = new XMLHttpRequest();
      httpRequest.onreadystatechange = function(response){
        try{
          if(httpRequest.readyState == 4){
            if(httpRequest.status == 200){
              me.handleGetWorkResponse(httpRequest.responseText);
            }else{
              setTimeout(3000, function(){ loadMoreWork(result) });
            }
          }
        }catch(e){
          setTimeout(3000, function(){ loadMoreWork(result) });
        }
      };
    } else { /* you're fucked! */}
    
    if(!httpRequest)
      return;

    if(!result){
      httpRequest.open('GET', url);
      httpRequest.send();
    }else{
      httpRequest.open('POST', url);
      httpRequest.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
      httpRequest.send(jsMiner.Util.toPoolString(result));
    }
  };
  
  this.handleGetWorkResponse = function(response){
    var work = eval("(" + response + ")");
    var midstate = jsMiner.Util.fromPoolString(work.midstate);
    var half = work.data.substring(0, 128);
    var data = work.data.substring(128, 256);
    data = jsMiner.Util.fromPoolString(data); 
    half = jsMiner.Util.fromPoolString(half);
    var hash1 = jsMiner.Util.fromPoolString(work.hash1);
    var target = jsMiner.Util.fromPoolString(work.target);  
    
    this.workerEntry(midstate, half, data, hash1, target, work.first_nonce, work.last_nonce);
  };
  
  this.webWorkerEntry = function(midstate, half, data, hash1, target, startNonce, endNonce){
    var me = this;
    var startTime = (new Date()).getTime() ;
    if(!this.webWorker){
      this.webWorker = new Worker('jsMiner.js');
    }
    this.webWorker.onmessage = function(event) {
      var stopTime = (new Date()).getTime() ;
      me.workerRunning = false;
      me.hashRate = (event.data.lastNonce - startNonce) / (stopTime - startTime) * 1000;
      me.loadMoreWork(event.data.data);
    };
    this.webWorker.postMessage({
      midstate: midstate,
      half: half,
      data: data, 
      hash1: hash1, 
      target: target, 
      startNonce: startNonce, 
      endNonce: endNonce,
      pubId: this.publisherId,
      timeout: this.workerTimeout
    });
  };
  
  this.workerEntry = function(midstate, half, data, hash1, target, startNonce, endNonce){
    if(!!window.Worker && !this.forceUIThread){
      this.webWorkerEntry(midstate, half, data, hash1, target, startNonce, endNonce);
      return;
    }
    var nonce = startNonce;
    var delay = this.delayBetweenNonce;
    var me = this;
    var startTime = (new Date()).getTime() ;
    var endTime = startTime + this.workerTimeout * 1000;
    this.workerRunning = true;
    
    var workerDone = function(result){
      var stopTime = (new Date()).getTime() ;
      me.workerRunning = false;
      me.hashRate = (nonce - startNonce) / (stopTime - startTime) * 1000;
      me.loadMoreWork(result);
    };
    
    function worker(){

      for(var i = 0; i != 100 && nonce < endNonce; i++){
        var hash =  me.tryHash(midstate, half, data, hash1, target, nonce);
        if(hash != null){
          workerDone(hash);
          return;
        }
        nonce++;
      }
      if(nonce++ < endNonce && (new Date()).getTime()  <= endTime)
        setTimeout(worker, delay);
      else
        workerDone(null);
    };
    setTimeout(worker, delay);
  };
  
  this.tryHash = function(midstate, half, data, hash1, target, nonce){  
    data[3] = nonce;
    this.sha.reset();

    var h0 = this.sha.update(midstate, data).state;   // compute first hash
    for (var i = 0; i < 8; i++) hash1[i] = h0[i];   // place it in the h1 holder
    this.sha.reset();                 // reset to initial state
    var h = this.sha.update(hash1).state;       // compute final hash
    if (h[7] == 0) {
      var ret = [];
      for (var i = 0; i < half.length; i++)
        ret.push(half[i]);
      for (var i = 0; i < data.length; i++)
        ret.push(data[i]);
      return ret;
    } else return null;
  };
          
  //bootstrap
  if(this.autoStart)
    this.loadMoreWork();
}

if (typeof window  == "undefined"){
  //then the code is running in a web worker.
  self.onmessage = function(event) {
    var startTime = (new Date()).getTime() ;
    var endTime = startTime + event.data.timeout * 1000;
    var engine = new jsMiner.engine({pubId: event.data.pubId, autoStart: false});
    for(var nonce = event.data.startNonce; nonce != event.data.endNonce; nonce++){
      var result = engine.tryHash(event.data.midstate, event.data.half, event.data.data, event.data.hash1, event.data.target, nonce);
      if(result){
        postMessage({data: result, lastNonce: nonce});
        return;
      }else if(nonce % 100 && (new Date()).getTime()  >= endTime){
        postMessage({data: null, lastNonce: nonce});
        return;
      }
    }
    postMessage({data: null, lastNonce: event.data.endNonce});
  };
}