// Check value's data type (object, string, number, function)
var checkType = function(data) {
  var typeString = Object.prototype.toString.call(data).split(' ');
  var type = typeString[1].slice(0, -1);

  return type;
}

// Self explanatory
var hasOwn = function(obj, key) {
  return obj.hasOwnProperty(key);
}

/**
  Check if two values are deepEqual regardless of its type. 'key' here is an
  attribute name, because if we're comparing objects we want to return the
  differences from it but we need to know the name of the attribute itself.
**/
var isEqual = function(value1, value2, callback, key) {
  // We only need to compare one because they will have the same type
  var type = checkType(value1);

  if(type === 'Array') {
  value1 = value1.sort();
  value2 = value2.sort();
    if (value1.length !== value2.length) { return false; }

    for (var x = 0; x < value1.length; x++) {
      if (checkType(value1[x]) === 'Object' && callback) {
        var result = callback(value1[x], value2[x], key);

        if(!result.one.length) { return true; }
      }

      else {
        for (var x = 0; x < value1.length; x++) {
          if (checkType(value1[x] === 'Function') && value1.toString() !== value2.toString()) {
            return false;
          }
           if (value1[x].toString() !== value2[x].toString()) {
             return false;
           };
        }
      }
    }
  }

  // If we're comparing objects, we need to go deep :kappa:
  else if (type === 'Object' && callback) {
    var result = callback(value1, value2, key);

    if(!result.one.length) { return true; }
  }

  else {
    if(value1.toString() !== value2.toString()) {
      return false;
    }
  }

  return true;
}

var result = {
  one: [],
  two: []
};

var deepDiff = function(objA, objB, key) {
  var keysA = Object.keys(objA);

  for (var i = 0; i < keysA.length; i++) {
    if (
      hasOwn(objB, keysA[i]) &&
      !isEqual(objA[keysA[i]], objB[keysA[i]], deepDiff, keysA[i])
    ) {
      if (key) {
        result.one.push({ [key]: { [keysA[i]]: objA[keysA[i]] }});
        result.two.push({ [key]: { [keysA[i]]: objB[keysA[i]] }});
      } else {
        result.one.push({ [keysA[i]]: objA[keysA[i]] });
        result.two.push({ [keysA[i]]: objB[keysA[i]] });
      }
    }
  }

  return result;
}