<?PHP
/**
 * Provides type-safe overrides of default PHP functions.
 */
declare(strict_types = 1);

/**
 * Standard class providing overrides of default PHP functions as static
 * functions.
 */
final class MD_STD {
    /**
     * Wrapper around file_get_contents, that provides catches errors on it and returns
     * with type safety.
     *
     * @param string $filename Filepath of the file to read.
     *
     * @return string
     */
    public static function file_get_contents(string $filename):string {

        if (\substr($filename, 0, 4) !== 'http' && !\file_exists($filename)) {
            throw new MDFileDoesNotExist("There is no file {$filename}");
        }

        $contents = \file_get_contents($filename);

        if (\is_bool($contents)) {
            throw new MDFileIsNotReadable("File {$filename} is not readable");
        }

        return $contents;

    }

    /**
     * Returns the real path of a relative file path. Throws an error rather than
     * returning the default false.
     *
     * @param string $path File path to convert.
     *
     * @return string
     */
    public static function realpath(string $path):string {

        $output = \realpath($path);
        if (!\is_string($output)) throw new MDFileDoesNotExist("The file {$path} does not exist or is not readable.");
        return $output;

    }

    /**
     * Gets contents of a folder.
     *
     * @param string $filepath Directory path.
     *
     * @return array<string>
     */
    public static function scandir(string $filepath):array {

        if (!\is_dir($filepath) || ($output = \scandir($filepath)) === false) {
            throw new MDFileDoesNotExist("There is no file {$filepath}");
        }

        // Remove unwanted files from list
        $output = \array_diff($output, ['.', '..', '.git']);

        // Return array values, to make it a list rather than an associative array.
        // This should be done in a separate line, as it observably leads to a
        // significant reduction in the used RAM.
        return \array_values($output);

    }

    /**
     * Type safe wrapper around ob_get_clean():  Gets the current buffer
     * contents and delete current output buffer.
     *
     * @return string
     */
    public static function ob_get_clean():string {

        $output = \ob_get_clean();
        if ($output === false) throw new MDOutputBufferNotStarted("Output buffer was not started");
        return $output;

    }

    /**
     * Function checking if a string starts with another.
     *
     * @param string $haystack String to check.
     * @param string $needle   Potential start of $haystack.
     *
     * @return boolean
     */
    public static function startsWith(string $haystack, string $needle):bool {

        if (substr($haystack, 0, \strlen($needle)) == $needle) return true;
        else return false;

    }

    /**
     * Function checking if a string starts with any input from the input array.
     *
     * @param string   $haystack String to check.
     * @param string[] $needles  Array containing potential start values of $haystack.
     *
     * @return boolean
     */
    public static function startsWithAny(string $haystack, array $needles):bool {

        $output = false;
        foreach ($needles as $needle) {
            $output = self::startsWith($haystack, $needle);
            if ($output == true) return $output;
        }
        return $output;

    }

    /**
     * Type-safe(r) wrapper around preg_replace.
     *
     * @param string $pattern     The pattern to search for. It can be either a string or an array with strings.
     * @param string $replacement To replace with.
     * @param string $subject     The string or an array with strings to search and replace.
     *
     * @return string
     */
    public static function preg_replace_str(string $pattern, string $replacement, string $subject):string {

        $output = \preg_replace($pattern, $replacement, $subject);
        if ($output === null) {
            throw new Exception("Error replacing in $subject: Replacing $pattern with $replacement");
        }

        return $output;

    }

    /**
     * Type-safe wrapper around json_encode.
     *
     * @see https://www.php.net/manual/en/function.json-encode.php
     *
     * @param array<mixed> $value   The value being encoded. Can be any type except a resource.
     * @param integer      $options Bitmask consisting of JSON_FORCE_OBJECT, JSON_HEX_QUOT ...
     * @param integer      $depth   Depth of coding.
     *
     * @return string
     */
    public static function json_encode(array $value, int $options = 0, int $depth = 512):string {

        $output = \json_encode($value, $options, $depth);
        if ($output === false) throw new Exception("JSON output could not be generated");
        return $output;

    }

    /**
     * Type-safe wrapper around strtotime().
     *
     * @param string $datetime String to convert.
     *
     * @return integer
     */
    public static function strtotime(string $datetime):int {

        $output = \strtotime($datetime);
        if ($output === false) throw new MDInvalidInputDate("Invalid input date {$datetime}.");
        return $output;

    }

    /**
     * Wrapper for curling contents from the web.
     *
     * @param string  $url     URL to query.
     * @param integer $timeout Timeout in milliseconds.
     *
     * @return string
     */
    public static function runCurl(string $url, int $timeout = 1200):string {

        $curl = \curl_init();

        \curl_setopt($curl, CURLOPT_URL, $url);
        \curl_setopt($curl, CURLOPT_HEADER, false);
        \curl_setopt($curl, CURLOPT_CONNECTTIMEOUT_MS, $timeout); //timeout in seconds
        \curl_setopt($curl, CURLOPT_TIMEOUT_MS, $timeout);        //timeout in seconds
        \curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        \curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);
        // \curl_setopt($curl, CURLOPT_COOKIESESSION, true);
        \curl_setopt($curl, CURLOPT_AUTOREFERER, true);
        \curl_setopt($curl, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:10.0.2) Gecko/20100101 Firefox/10.0.2');
        $result = \curl_exec($curl);

        // if ($err = curl_errno($curl)) echo $err;
        // if ($errmsg  = curl_error($curl)) echo $errmsg;

        \curl_close($curl);
        if (\is_bool($result)) return "";
        return $result;

    }

    /**
     * Function lang_getfrombrowser gets the browser language based on HTTP headers.
     *
     * @param array<string> $allowed_languages Array containing all the languages for which
     *                                         there are translations.
     * @param string        $default_language  Default language of the instance of MD.
     * @param string        $lang_variable     Currently set language variable. Optional.
     * @param boolean       $strict_mode       Whether to demand "de-de" (true) or "de" (false) Optional.
     *
     * @return string
     */
    public static function lang_getfrombrowser(array $allowed_languages, string $default_language, string $lang_variable = "", bool $strict_mode = true):string {

        // $_SERVER['HTTP_ACCEPT_LANGUAGE'] verwenden, wenn keine Sprachvariable mitgegeben wurde
        if ($lang_variable === "") {
            if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) $lang_variable = $_SERVER['HTTP_ACCEPT_LANGUAGE'];
        }

        // wurde irgendwelche Information mitgeschickt?
        if (empty($lang_variable)) {
            // Nein? => Standardsprache zurückgeben
            return $default_language;
        }

        // Den Header auftrennen
        $accepted_languages = preg_split('/,\s*/', $lang_variable);
        if (!is_array($accepted_languages)) return $default_language;

        // Die Standardwerte einstellen
        $current_lang = $default_language;
        $current_q = 0;

        // Nun alle mitgegebenen Sprachen abarbeiten
        foreach ($accepted_languages as $accepted_language) {

            // Alle Infos über diese Sprache rausholen
            // phpcs:disable Generic.Strings.UnnecessaryStringConcat
            $res = \preg_match('/^([a-z]{1,8}(?:-[a-z]{1,8})*)(?:;\s*q=(0(?:\.[0-9]{1,3})?|1(?:\.0{1,3})?))?$/i', $accepted_language, $matches);
            // phpcs:enable

            // war die Syntax gültig?
            if (!$res) {
                // Nein? Dann ignorieren
                continue;
            }

            // Sprachcode holen und dann sofort in die Einzelteile trennen
            $lang_code = \explode('-', $matches[1]);

            // Wurde eine Qualität mitgegeben?
            if (isset($matches[2])) {
                // die Qualität benutzen
                $lang_quality = (float)$matches[2];
            } else {
                // Kompabilitätsmodus: Qualität 1 annehmen
                $lang_quality = 1.0;
            }

            // Bis der Sprachcode leer ist...
            // phpcs:disable Squiz.PHP.DisallowSizeFunctionsInLoops
            while (!empty($lang_code)) {
                // phpcs:enable
                // mal sehen, ob der Sprachcode angeboten wird
                if (\in_array(\strtolower(\join('-', $lang_code)), $allowed_languages, true)) {
                    // Qualität anschauen
                    if ($lang_quality > $current_q) {
                        // diese Sprache verwenden
                        $current_lang = \strtolower(join('-', $lang_code));
                        $current_q = $lang_quality;
                        // Hier die innere while-Schleife verlassen
                        break;
                    }
                }
                // Wenn wir im strengen Modus sind, die Sprache nicht versuchen zu minimalisieren
                if ($strict_mode) {
                    // innere While-Schleife aufbrechen
                    break;
                }
                // den rechtesten Teil des Sprachcodes abschneiden
                \array_pop($lang_code);
            }
        }

        // die gefundene Sprache zurückgeben
        return $current_lang;

    }

    /**
     * Type-safe wrapper around filesize, if output is false, throws an error.
     *
     * @param string $filename File name.
     *
     * @return integer
     */
    public static function filesize(string $filename):int {

        $output = \filesize($filename);

        if ($output === false) {
            throw new Exception("Cannot get filesize of file {$filename}");
        }

        return $output;

    }

    /**
     * Function human_filesize translates byte-level filesizes to human readable ones.
     * Thanks to Jeffrey Sambells http://jeffreysambells.com/2012/10/25/human-readable-filesize-php
     *
     * @param integer $bytes    A file size, e.g. returned from filesize().
     * @param integer $decimals Number of decimal digits to allow.
     *
     * @return string
     */
    public static function human_filesize(int $bytes, int $decimals = 2):string {

        $size = ['B','kB','MB','GB','TB','PB','EB','ZB','YB'];
        $factor = \floor((\strlen((string)$bytes) - 1) / 3);
        return \sprintf("%.{$decimals}f", $bytes / \pow(1024, $factor)) . $size[$factor];

    }

    /**
     * Type-safe wrapper around openssl_random_pseudo_bytes.
     *
     * @param integer $length Length.
     *
     * @return string
     */
    public static function openssl_random_pseudo_bytes(int $length):string {

        $output = \openssl_random_pseudo_bytes($length);
        if ($output === false) throw new Exception("Failed generating random pseudo bytes using openssl_random_pseudo_bytes");
        return $output;

    }

    /**
     * Function for minimizing HTML, trimming each line.
     *
     * @param string $input Input.
     *
     * @return string
     */
    public static function minimizeHTMLString(string $input):string {

        $input = \explode(PHP_EOL, $input);
        $output = "";
        foreach ($input as $line) $output .= \trim($line) . PHP_EOL;
        return $output;

    }

    /**
     * This function cuts down a string and adds a period in case it's longer
     * than length to create a snippet.
     *
     * @param string  $string Input text to cut down.
     * @param integer $length Length of the snippet to create.
     *
     * @return string
     */
    public static function createTextSnippet(string $string, int $length = 180):string {

        if (\mb_strlen($string) > $length) {
            $string  = \mb_substr($string, 0, $length);
            if (($lastWhitespace = \mb_strrpos($string, ' ')) !== false) {
                $string = \mb_substr($string, 0, $lastWhitespace);
            }
            $string .= '...';
        }
        return $string;

    }

    /**
     * Wrapper around the finfo functions to get the mime content type of a file.
     *
     * @param string $filepath Expected file path.
     *
     * @return string
     */
    public static function mime_content_type(string $filepath):string {

        if (!($finfo = \finfo_open(FILEINFO_MIME_TYPE))) {
            throw new Exception("Cannot open finfo context");
        }
        if (!($mime_type = finfo_file($finfo, $filepath))) {
            throw new MDWrongFileType("Cannot get mime type of file: " . basename($filepath));
        }
        \finfo_close($finfo);

        return $mime_type;

    }

    /**
     * Checks if a file exists, with one of the expected mime types.
     *
     * @param string   $filepath          File path of the file that needs to exist.
     * @param string[] $accepted_mimetype Mime type the file should have.
     *
     * @return void
     */
    public static function ensure_file(string $filepath, array $accepted_mimetype = []) {

        if (!\file_exists($filepath)) {
            throw new MDFileDoesNotExist("File " . basename($filepath) . " does not exist");
        }

        // Check for mime type follows. If no check is to be done, ignore this.
        if (empty($accepted_mimetype)) {
            return;
        }

        $mime_type = self::mime_content_type($filepath);

        if (!\in_array($mime_type, $accepted_mimetype, true)) {
            throw new MDWrongFileType("Incorrect mime type of file " . \basename($filepath) . ". Mime type is " . \mime_content_type($filepath) . ", accepted any of ['" . \implode("', '", $accepted_mimetype) . "']");
        }

    }

    /**
     * Wrapper around exec, to be used with editing functions.
     * Pipes STDERR to STDOUT and throws an Exception on any error.
     *
     * @param string $cmds Commands to run.
     *
     * @return void
     */
    public static function exec_edit(string $cmds):void {

        $error = \exec($cmds . ' 2>&1');
        if (!empty($error)) {
            throw new \Exception('Shell error: ' . $error);
        }

    }

    /**
     * Wrapper around levenshtein(), that only compares the first 250
     * characters (levenshtein can't handle more than 255).
     *
     * @param string $str1 First string.
     * @param string $str2 Second string.
     *
     * @return integer
     */
    public static function levenshtein(string $str1, string $str2):int {

        if (\strlen($str1) > 250) $str1 = \substr($str1, 0, 250);
        if (\strlen($str2) > 250) $str2 = \substr($str2, 0, 250);

        return \levenshtein($str1, $str2);

    }
}