<?php

/**
 * Namespace for classes and functions related to the game Factorio.
 * @package NAE\Factorio
 */
namespace NAE\Factorio;

/**
 * Class for parsing and comparing Factorio versions.
 * @author "Marcel Naeve" <php@naeve.info>
 * @license MIT License (http://www.opensource.org/licenses/mit)
 */
class FactorioVersion {

    /**
     * @var string The Factorio Version
     */
    private $version;

    /**
     * @var int The Factorio version converted to an comparable integer.
     */
    private $intVersion;


    /**
     * Fills a string with zeros at the beginning till string length matches the target length.
     * @param string $str string to fill
     * @param int $target_length Target length of the string
     * @return string string with zeros at the beginning till string length matches
     */
    private function zero_fill(string $str, int $target_length) {

        if(strlen($str) >= $target_length) {
            return $str;
        }
        $missing = ( $target_length - strlen($str) );
        for($i=0;$i<$target_length;$i++) {
            $str = "0".$str;
        }

        return $str;

    }

    /**
     * Formats the Factorio version string to a comparable integer.
     * @param string $vs Factorio version string (example: 2.0.14)
     * @return int factorio version as comparable integer (example: versionFormat("2.0.14") -> "000200000014" -> int(200000014))
     */
    private function versionFormat(string $vs) : int {

        $parts = explode(".", $vs);
        $new = "";

        foreach($parts as $i => $v) {
            $new .= $this->zero_fill($v, 4);
        }

        return intval($new);

    }

    /**
     * Constructor.
     * @param string $version Factorio version string (example: 2.0.14)
     */
    public function __construct(string $version) {
        $this->version = $version;
        $this->intVersion = $this->versionFormat($version);
    }

    /**
     * Returns the Factorio version string (example: 2.0.14).
     * @return string Factorio version string (example: 2.0.14)
     */
    public function getVersion() : string {
        return $this->version;
    }

    /**
     * Returns the Factorio version as a comparable integer (example: versionFormat("2.0.14") -> int(200000014)).
     * @return integer Factorio version as a comparable integer (example: versionFormat("2.0.14") -> int(200000014)).
     */
    public function getIntVersion() : int {
        return $this->intVersion;
    }

    /**
     * Checks if the current Factorio version is newer than another version.
     * @param FactorioVersion $other Another FactorioVersion object
     */
    public function isNewer(FactorioVersion $other) : bool {
        return $this->intVersion > $other->getIntVersion();
    }

    /**
     * Checks if the current Factorio version is older than another version.
     * @param FactorioVersion $other Another FactorioVersion object
     */
    public function isOlder(FactorioVersion $other) : bool {
        return $this->intVersion < $other->getIntVersion();
    }

}