<?php

namespace yiiaddon\helpers;

/**
 * @category  PHP
 * @package   adeattwood\yii-helpers
 * @author    Ade Attwood <attwood16@googlemail.com>
 * @copyright 2017 adeattwood.co.uk
 * @license   BSD-2-Clause http://adeattwood.co.uk/license.html
 * @link      adeattwood.co.uk
 * @since     v0.1
 */
class Enum extends \yii\base\Object
{
    const TYPE_ARRAY    = 'array';
    const TYPE_NULL     = 'null';
    const TYPE_BOOL     = 'boolean';
    const TYPE_FLOAT    = 'float';
    const TYPE_INT      = 'integer';
    const TYPE_DATETIME = 'datetime';
    const TYPE_STRING   = 'string';
    const TYPE_RESOURCE = 'resource';
    const TYPE_UNKNOWN  = 'unknown';

   /**
    *
     * Parses and returns a variable type
     *
     * Example:
     *
     * ~~~php
     * $data = [
     *     'id' => 1,
     *     'name' => 'Smith',
     *     'date' => '2014/01/22',
     *     'amount' => '4,323.23',
     *     'relations' => ['spouse', 'children']
     * ];
     * foreach ($data as $k=>$v) {
     *     echo "<b>$k</b>: " . Enum::getType($v) . "<br>";
     * }
     * ~~~
     *
     * @param string $var the variable to be parsed
     *
     * @return string
     */
    public static function getType( $var )
    {
        switch( $var ) {
            case is_null( $var ):
                return self::TYPE_NULL;
            case is_array( $var ):
                return self::TYPE_ARRAY;
            case is_bool( $var ):
                return self::TYPE_BOOL;
            case is_float( $var ):
            case is_numeric( str_replace( ',', '', $var ) ) && strpos( $var, '.' ) > 0 && is_float( ( float )str_replace( ',', '', $var ) ):
                return self::TYPE_FLOAT;
            case is_int( $var ) || ( is_numeric( $var ) && is_int( ( int )$var ) ):
                return self::TYPE_INT;
            case is_scalar( $var ) && strtotime( $var ) !== false:
                return self::TYPE_DATETIME;
            case is_scalar( $var ):
                return self::TYPE_STRING;
            default:
                return self::TYPE_UNKNOWN;
        }
    }

    /**
     * Check if a variable is empty or not set.
     *
     * Example:
     *
     * ~~~php
     * if (Enum::isEmpty([]) {
     *    echo 'Not empty';
     * }
     * ~~~
     *
     * @param mixed $var variable to perform the check
     *
     * @return boolean
     */
    public static function isEmpty( $var )
    {
        return !isset( $var ) ? true : ( is_array( $var ) ? empty( $var ) : ( $var === null || $var === '' ) );
    }

    /**
     * Format and convert "bytes" to its optimal higher metric unit.
     *
     * Example:
     *
     * ~~~php
     * echo Enum::formatBytes(120.32); // returns: 1.17 KB
     * echo Enum::formatBytes(28434322.25); // returns: 27.12 MB
     * echo Enum::formatBytes(17328347842.25, 3); // returns: 16.138 GB
     * ~~~
     *
     * @param double  $bytes     number of bytes
     * @param integer $precision the number of decimal places to round off
     *
     * @return string
     */
    public static function formatBytes( $bytes, $precision = 2 )
    {
        $units = [ 'B', 'KB', 'MB', 'GB', 'TB' ];
        $bytes = max( $bytes, 0 );
        $pow = floor( ( $bytes ? log( $bytes ) : 0 ) / log( 1024 ) );
        $pow = min( $pow, count( $units ) - 1 );
        $bytes /= pow( 1024, $pow );
        return round( $bytes, $precision ) . ' ' . $units[$pow];
    }
}