'use strict';
var imports     = require('soop').imports();
var bitcore     = require('bitcore');
var BIP32       = bitcore.BIP32;
var Address     = bitcore.Address;
var Script      = bitcore.Script;
var coinUtil    = bitcore.util;
var Transaction = bitcore.Transaction;

var Storage     = imports.Storage || require('./Storage');
var log         = imports.log || console.log;

var storage     = Storage.default();

/*
 * This follow Electrum convetion, as described on
 * https://bitcointalk.org/index.php?topic=274182.0
 *
 * We should probably adapt the next standard once its ready as discussed at:
 * http://sourceforge.net/p/bitcoin/mailman/message/32148600/
 *
 */

var PUBLIC_BRANCH = 'm/0/';
var CHANGE_BRANCH = 'm/1/';


function Wallet(opts) {
  opts = opts || {};

  this.network = opts.network === 'livenet' ? 
      bitcore.networks.livenet : bitcore.networks.testnet;

  this.requiredCosigners = opts.requiredCosigners || 3;
  this.totalCosigners = opts.totalCosigners || 5;

  this.id = opts.id || Wallet.getRandomId();

  this.dirty = 1;
  this.cosignersWallets = [];
  this.bip32 = new BIP32(opts.bytes ||  this.network.name);

  this.changeAddressIndex=0;
  this.addressIndex=0;

}


Wallet.getRandomId = function () {
  return coinUtil.generateNonce().toString('hex');
};

Wallet.decrypt = function (passphrase, encPayload) {
  log('[wallet.js.35] TODO READ: passphrase IGNORED');
  return encPayload;
};

Wallet.encrypt = function (passphrase, payload) {
  log('[wallet.js.92] TODO: passphrase IGNORED');
  return payload;
};

Wallet.read = function (id, passphrase) {
  var encPayload = storage.read(id);
  if (!encPayload) 
    throw new Error('Could not find wallet data');
  var data;
  try {
    data = JSON.parse( Wallet.decrypt( passphrase, encPayload ));
  } catch (e) {
    throw new Error('error in storage: '+ e.toString());
    return;
  };

  if (data.id !== id) 
    throw new Error('Wrong id in data');

  var config = { network: data.network === 'livenet' ? 
      bitcore.networks.livenet : bitcore.networks.testnet
  };

  var w = new Wallet(config);

  w.requiredCosigners = data.neededCosigners;
  w.totalCosigners = data.totalCosigners;
  w.cosignersWallets = data.cosignersExtPubKeys.map( function (pk) { 
    return new Wallet({bytes:pk, network: w.network.name});
  });

  w.dirty = 0;

  return w;
};

Wallet.prototype.serialize = function () {
  return JSON.stringify({
    id: this.id,
    network: this.network.name,
    requiredCosigners: this.neededCosigners,
    totalCosigners: this.totalCosigners,
    cosignersExtPubKeys: this.cosignersWallets.map( function (b) { 
      return b.getMasterExtendedPubKey(); 
    }),
    priv: this.getMasterExtendedPrivKey(),
  });
};

Wallet.prototype.store = function (passphrase) {

  if (!this.id) 
      throw new Error('wallet has no id');

  storage.save(this.id, Wallet.encrypt(passphrase,this.serialize()));
  this.dirty = 0;

  return true;
};

Wallet.prototype.registeredCosigners = function () {
  if (! this.cosignersWallets) return 1;


  // 1 is self.
  return 1 + this.cosignersWallets.length;
};

Wallet.prototype.getMasterExtendedPrivKey = function () {

  if (!this.bip32) 
      throw new Error('no priv key defined on the wallet');

  return this.bip32.extended_private_key_string();
};


Wallet.prototype.getMasterExtendedPubKey = function () {
  return this.bip32.extended_public_key_string();
};


Wallet.prototype.haveAllRequiredPubKeys = function () {
  return this.registeredCosigners() === this.totalCosigners;
};

Wallet.prototype._checkKeys = function() {

  if (!this.haveAllRequiredPubKeys())
      throw new Error('dont have required keys yet');
};


//  should receive an array also?
Wallet.prototype.addCosignerExtendedPubKey = function (newEpk) {

  if (this.haveAllRequiredPubKeys())
      throw new Error('already have all required key:' + this.totalCosigners);

  if (this.getMasterExtendedPubKey() === newEpk)
    throw new Error('already have that key (self key)');


  this.cosignersWallets.forEach(function(b){
    if (b.getMasterExtendedPubKey() === newEpk)
      throw new Error('already have that key');
  });

  this.cosignersWallets.push(new Wallet({bytes:newEpk, network: this.network.name } ));
  this.dirty = 1;
};


Wallet.prototype.getPubKey = function (index,isChange) {

  var path = (isChange ? CHANGE_BRANCH : PUBLIC_BRANCH) + index;
  var bip32 = this.bip32.derive(path);
  var pub   = bip32.eckey.public;
  return pub;
};




Wallet.prototype.getCosignersPubKeys = function (index, isChange) {
  this._checkKeys();

  var pubKeys = [];
  var l = this.cosignersWallets.length;
  for(var i=0; i<l; i++) {
    pubKeys[i] = this.cosignersWallets[i].getPubKey(index, isChange);
  }

  return pubKeys;
};


Wallet.prototype.getCosignersSortedPubKeys = function(index, isChange) {
  var self = this;
  var pubKeys = self.getCosignersPubKeys(index, isChange);

  //sort lexicographically, i.e. as strings, i.e. alphabetically
  // From https://github.com/ryanxcharles/treasure/blob/master/treasure.js
  return pubKeys.sort(function(buf1, buf2) {
    var len = buf1.length > buf1.length ? buf1.length : buf2.length;
    for (var i = 0; i <= len; i++) {
      if (buf1[i] === undefined)
        return -1; //shorter strings come first
      if (buf2[i] === undefined)
        return 1;
      if (buf1[i] < buf2[i])
        return -1;
      if (buf1[i] > buf2[i])
        return 1;
      else
        continue;
    }
    return 0;
  });
};



Wallet.prototype.getAddress = function (index, isChange) {

  if ( (isChange && index > this.changeAddressIndex)
      || (!isChange && index > this.addressIndex)) {
    log('Out of bounds at getAddress: Index %d isChange: %d', index, isChange);
    throw new Error('index out of bound');
  }

  var pubKeys = this.getCosignersSortedPubKeys(index, isChange);

  var version = this.network.addressScript;
  var script  = Script.createMultisig(this.requiredCosigners, pubKeys);
  var buf     = script.buffer;
  var hash    = coinUtil.sha256ripe160(buf);
  var addr    = new Address(version, hash);
  var addrStr = addr.as('base58');
  return addrStr;
};

Wallet.prototype.createAddress = function(isChange) {

  var ret =  
    this.getAddress(isChange ? this.changeAddressIndex : this.addressIndex, isChange);

  if (isChange) 
    this.addressIndex++;
  else 
    this.changeAddressIndex++;

  return ret;

};

Wallet.prototype.getAddresses = function() {
  var ret = [];

  for (var i=0; i<this.changeAddressIndex; i++) {
    ret.push(this.getAddress(i,true));
  }

  for (var i=0; i<this.addressIndex; i++) {
    ret.push(this.getAddress(i,false));
  }
  return ret;
};

Wallet.prototype.createTx = function(utxos,outs) {
  var opts = {
    remainderAddress: this.createAddress(1),
  };
  return Transaction.create(utxos, outs, opts);
};

// Input: Bitcore's Transaction, sign with ownPK
// return partially signed or fully signed tx
Wallet.prototype.signTx = function (tx) {
};

module.exports = require('soop')(Wallet);