var createPadding = require('./_createPadding'),

stringSize = require('./_stringSize'),
toInteger = require('./toInteger'),
toString = require('./toString');

/* Built-in method references for those with the same name as other `lodash` methods. */ var nativeCeil = Math.ceil,

nativeFloor = Math.floor;

/**

* Pads `string` on the left and right sides if it's shorter than `length`.
* Padding characters are truncated if they can't be evenly divided by `length`.
*
* @static
* @memberOf _
* @since 3.0.0
* @category String
* @param {string} [string=''] The string to pad.
* @param {number} [length=0] The padding length.
* @param {string} [chars=' '] The string used as padding.
* @returns {string} Returns the padded string.
* @example
*
* _.pad('abc', 8);
* // => '  abc   '
*
* _.pad('abc', 8, '_-');
* // => '_-abc_-_'
*
* _.pad('abc', 3);
* // => 'abc'
*/

function pad(string, length, chars) {

string = toString(string);
length = toInteger(length);

var strLength = length ? stringSize(string) : 0;
if (!length || strLength >= length) {
  return string;
}
var mid = (length - strLength) / 2;
return (
  createPadding(nativeFloor(mid), chars) +
  string +
  createPadding(nativeCeil(mid), chars)
);

}

module.exports = pad;