<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Requirements;

/**
 * Represents a requirement in form of a PHP configuration option.
 *
 * @author Tobias Schultze <http://tobion.de>
 */
class PhpConfigRequirement extends Requirement
{
    /**
     * Constructor that initializes the requirement.
     *
     * @param string        $cfgName           The configuration name used for ini_get()
     * @param bool|callback $evaluation        Either a boolean indicating whether the configuration should evaluate to true or false,
     *                                         or a callback function receiving the configuration value as parameter to determine the fulfillment of the requirement
     * @param bool          $approveCfgAbsence If true the Requirement will be fulfilled even if the configuration option does not exist, i.e. ini_get() returns false.
     *                                         This is helpful for abandoned configs in later PHP versions or configs of an optional extension, like Suhosin.
     *                                         Example: You require a config to be true but PHP later removes this config and defaults it to true internally.
     * @param string|null   $testMessage       The message for testing the requirement (when null and $evaluation is a boolean a default message is derived)
     * @param string|null   $helpHtml          The help text formatted in HTML for resolving the problem (when null and $evaluation is a boolean a default help is derived)
     * @param string|null   $helpText          The help text (when null, it will be inferred from $helpHtml, i.e. stripped from HTML tags)
     * @param bool          $optional          Whether this is only an optional recommendation not a mandatory requirement
     */
    public function __construct($cfgName, $evaluation, $approveCfgAbsence = false, $testMessage = null, $helpHtml = null, $helpText = null, $optional = false)
    {
        $cfgValue = ini_get($cfgName);

        if (is_callable($evaluation)) {
            if (null === $testMessage || null === $helpHtml) {
                throw new \InvalidArgumentException('You must provide the parameters testMessage and helpHtml for a callback evaluation.');
            }

            $fulfilled = call_user_func($evaluation, $cfgValue);
        } else {
            if (null === $testMessage) {
                $testMessage = sprintf('%s %s be %s in php.ini',
                    $cfgName,
                    $optional ? 'should' : 'must',
                    $evaluation ? 'enabled' : 'disabled'
                );
            }

            if (null === $helpHtml) {
                $helpHtml = sprintf('Set <strong>%s</strong> to <strong>%s</strong> in php.ini<a href="#phpini">*</a>.',
                    $cfgName,
                    $evaluation ? 'on' : 'off'
                );
            }

            $fulfilled = $evaluation == $cfgValue;
        }

        parent::__construct($fulfilled || ($approveCfgAbsence && false === $cfgValue), $testMessage, $helpHtml, $helpText, $optional);
    }
}
