var assignValue = require('./_assignValue'),

castPath = require('./_castPath'),
isIndex = require('./_isIndex'),
isObject = require('./isObject'),
toKey = require('./_toKey');

/**

* The base implementation of `_.set`.
*
* @private
* @param {Object} object The object to modify.
* @param {Array|string} path The path of the property to set.
* @param {*} value The value to set.
* @param {Function} [customizer] The function to customize path creation.
* @returns {Object} Returns `object`.
*/

function baseSet(object, path, value, customizer) {

if (!isObject(object)) {
  return object;
}
path = castPath(path, object);

var index = -1,
    length = path.length,
    lastIndex = length - 1,
    nested = object;

while (nested != null && ++index < length) {
  var key = toKey(path[index]),
      newValue = value;

  if (index != lastIndex) {
    var objValue = nested[key];
    newValue = customizer ? customizer(objValue, key, nested) : undefined;
    if (newValue === undefined) {
      newValue = isObject(objValue)
        ? objValue
        : (isIndex(path[index + 1]) ? [] : {});
    }
  }
  assignValue(nested, key, newValue);
  nested = nested[key];
}
return object;

}

module.exports = baseSet;