Wallet/src/js/controllers/amount.js

'use strict';

angular.module('copayApp.controllers').controller('amountController', function($rootScope, $scope, $filter, $timeout, $ionicScrollDelegate, gettextCatalog, platformInfo, lodash, configService, rateService, $stateParams, $window, $state, $log, txFormatService) {

  var unitToSatoshi;
  var satToUnit;
  var unitDecimals;
  var satToBtc;
  var self = $scope.self;
  var SMALL_FONT_SIZE_LIMIT = 13;
  var LENGTH_EXPRESSION_LIMIT = 19;

  $scope.isWallet = $stateParams.isWallet;
  $scope.toAddress = $stateParams.toAddress;
  $scope.toName = $stateParams.toName;
  $scope.toEmail = $stateParams.toEmail;

  $scope.$on('$ionicView.leave', function() {
    angular.element($window).off('keydown');
  });

  $scope.$on("$ionicView.enter", function(event, data) {

    if (!$stateParams.toAddress) {
      $log.error('Bad params at amount')
      throw ('bad params');
    }

    var reNr = /^[1234567890\.]$/;
    var reOp = /^[\*\+\-\/]$/;

    var disableKeys = angular.element($window).on('keydown', function(e) {
      if (e.which === 8) { // you can add others here inside brackets.
        e.preventDefault();
        $scope.removeDigit();
      }

      if (e.key && e.key.match(reNr))
        $scope.pushDigit(e.key);

      else if (e.key && e.key.match(reOp))
        $scope.pushOperator(e.key);

      else if (e.key && e.key == 'Enter')
        $scope.finish();

      $timeout(function() {
        $scope.$apply();
      }, 10);

    });

    var config = configService.getSync().wallet.settings;
    $scope.unitName = config.unitName;
    $scope.alternativeIsoCode = config.alternativeIsoCode;
    $scope.specificAmount = $scope.specificAlternativeAmount = '';
    $scope.isCordova = platformInfo.isCordova;
    unitToSatoshi = config.unitToSatoshi;
    satToUnit = 1 / unitToSatoshi;
    satToBtc = 1 / 100000000;
    unitDecimals = config.unitDecimals;

    $scope.resetAmount();

    // in SAT ALWAYS
    if ($stateParams.toAmount) {
      $scope.amount = (($stateParams.toAmount) * satToUnit).toFixed(unitDecimals);
    }

    processAmount($scope.amount);

    $timeout(function() {
      $ionicScrollDelegate.resize();
    }, 10);
  });

  $scope.toggleAlternative = function() {
    $scope.showAlternativeAmount = !$scope.showAlternativeAmount;

    if ($scope.amount && isExpression($scope.amount)) {
      var amount = evaluate(format($scope.amount));
      $scope.globalResult = '= ' + processResult(amount);
    }
  };

  function checkFontSize() {
    if ($scope.amount && $scope.amount.length >= SMALL_FONT_SIZE_LIMIT) $scope.smallFont = true;
    else $scope.smallFont = false;
  };

  $scope.pushDigit = function(digit) {
    if ($scope.amount && $scope.amount.length >= LENGTH_EXPRESSION_LIMIT) return;

    $scope.amount = ($scope.amount + digit).replace('..', '.');
    checkFontSize();
    processAmount($scope.amount);
  };

  $scope.pushOperator = function(operator) {
    console.log('[amount.js.90:operator:]', operator); //TODO
    if (!$scope.amount || $scope.amount.length == 0) return;
    $scope.amount = _pushOperator($scope.amount);

    function _pushOperator(val) {
      if (!isOperator(lodash.last(val))) {
        return val + operator;
      } else {
        return val.slice(0, -1) + operator;
      }
    };
  };

  function isOperator(val) {
    var regex = /[\/\-\+\x\*]/;
    return regex.test(val);
  };

  function isExpression(val) {
    var regex = /^\.?\d+(\.?\d+)?([\/\-\+\*x]\d?\.?\d+)+$/;

    return regex.test(val);
  };

  $scope.removeDigit = function() {
    $scope.amount = $scope.amount.slice(0, -1);
    processAmount($scope.amount);
    checkFontSize();
  };

  $scope.resetAmount = function() {
    $scope.amount = $scope.alternativeResult = $scope.amountResult = $scope.globalResult = '';
    checkFontSize();
  };

  function processAmount(val) {
    if (!val) {
      $scope.resetAmount();
      return;
    }

    var formatedValue = format(val);
    var result = evaluate(formatedValue);

    if (lodash.isNumber(result)) {
      $scope.globalResult = isExpression(val) ? '= ' + processResult(result) : '';
      $scope.amountResult = $filter('formatFiatAmount')(toFiat(result));
      $scope.alternativeResult = txFormatService.formatAmount(fromFiat(result) * unitToSatoshi, true);
    }
  };

  function processResult(val) {
    if ($scope.showAlternativeAmount)
      return $filter('formatFiatAmount')(val);
    else
      return txFormatService.formatAmount(val.toFixed(unitDecimals) * unitToSatoshi, true);
  };

  function fromFiat(val) {
    return parseFloat((rateService.fromFiat(val, $scope.alternativeIsoCode) * satToUnit).toFixed(unitDecimals), 10);
  };

  function toFiat(val) {
    return parseFloat((rateService.toFiat(val * unitToSatoshi, $scope.alternativeIsoCode)).toFixed(2), 10);
  };

  function evaluate(val) {
    var result;
    try {
      result = $scope.$eval(val);
    } catch (e) {
      return 0;
    }
    if (!lodash.isFinite(result)) return 0;
    return result;
  };

  function format(val) {
    var result = val.toString();

    if (isOperator(lodash.last(val)))
      result = result.slice(0, -1);

    return result.replace('x', '*');
  };

  $scope.finish = function() {
    var _amount = evaluate(format($scope.amount));
    var amount = $scope.showAlternativeAmount ? fromFiat(_amount).toFixed(unitDecimals) : _amount.toFixed(unitDecimals);

    $state.transitionTo('tabs.send.confirm', {
      isWallet: $scope.isWallet,
      toAmount: amount * unitToSatoshi,
      toAddress: $scope.toAddress,
      toName: $scope.toName,
      toEmail: $scope.toEmail
    });
  };
});