<?php

lessSorter($argv[1] ?? 'php://stdin');

function cleanRow($key, $row): string
{
    return preg_replace(
        '#  +#',
        ' ',
        str_replace(
            ["\t", "\n", "\r"],
            ' ',
            str_replace(
                ':',
                ': ',
                str_replace(
                    '>',
                    ' > ',
                    trim($key)
                ) . ' { ' . $row . ' }'
            )
        )
    );
}

function lessSorter($filename)
{
    $f = fopen($filename, 'rb');
    $lastKey = '';
    $buffer = '';
    $dqOpen = false;
    $sqOpen = false;
    while (!feof($f)) {
        $input = fread($f, 20480);
        while ($input) {
            $pos = [
                'open' => strpos($input, '{'),
                'close' => strpos($input, '}'),
                'end' => strpos($input, ';'),
                'sq' => strpos($input, "'"),
                'dq' => strpos($input, '"'),
            ];
            $pos = array_filter($pos, 'is_numeric');
            if (!$pos) {
                $buffer .= $input;
                $input = false;
                continue;
            }
            asort($pos);
            $firstPos = reset($pos);
            switch (key($pos)) {
                case 'open':
                    $lastKeys = explode(',', $buffer . substr($input, 0, $firstPos));
                    $buffer = '';
                    $input = substr($input, $firstPos + 1);
                    break;

                case 'close':
                    $row = trim($buffer . substr($input, 0, $firstPos));
                    $buffer = '';
                    $input = substr($input, $firstPos + 1);
                    if ($row) {
                        foreach($lastKeys as $lastKey) {
                            echo cleanRow($lastKey, $row . ';'), PHP_EOL;
                        }
                    }
                    $lastKeys = [];
                    break;

                case 'end':
                    $row = $buffer . substr($input, 0, $firstPos + 1);
                    $buffer = '';
                    $input = substr($input, $firstPos + 1);
                    foreach($lastKeys as $lastKey) {
                        echo cleanRow($lastKey, $row), PHP_EOL;
                    }
                    break;

                case 'sq':
                    $buffer .= substr($input, 0, $firstPos + 1);
                    $input = substr($input, $firstPos + 1);
                    $sqOpen = !$sqOpen;
                    break;

                case 'dq':
                    $buffer .= substr($input, 0, $firstPos + 1);
                    $input = substr($input, $firstPos + 1);
                    $dqOpen = !$dqOpen;
                    break;

                default:
                    die('unknown key');
            }
        }
    }

    fclose($f);

    if (trim($buffer)) {
        $buffer = preg_replace('#/\*.*\*/#', '', $buffer);
        if (trim($buffer)) {
            throw new \RuntimeException('Unexpected end of file: ' . $buffer);
        }
    }

    if ($lastKeys) {
        throw new \RuntimeException('Last block not closed');
    }
}