compile.php

<?php

// explicitly give VERSION via ENV or ask git for current version
$version = getenv('VERSION');
if ($version === false) {
    $version = ltrim(exec('git describe --always --dirty', $unused, $code), 'v');
    if ($code !== 0) {
        fwrite(STDERR, 'Error: Unable to get version info from git. Try passing VERSION via ENV' . PHP_EOL);
        exit(1);
    }
}

// use first argument as output file or use "leproxy-{version}.php"
$out = isset($argv[1]) ? $argv[1] : ('leproxy-' . $version . '.php');

system('composer install --no-dev --classmap-authoritative');
$classes = require __DIR__ . '/vendor/composer/autoload_classmap.php';
$includes = require __DIR__ . '/vendor/composer/autoload_files.php';
system('composer install');

echo 'Loading ' . count($classes) . ' classes to determine load order...';

// register autoloader which remembers load order
$ordered = array();
spl_autoload_register(function ($name) use ($classes, &$ordered) {
    require $classes[$name];
    $ordered[$name] = $classes[$name];
});

// use actual include file instead of include wrapper
foreach ($includes as $i => $path) {
    $includes[$i] = str_replace('_include.php', '.php', $path);

    require $path;
}

// load each class (and its superclasses once) into memory
foreach ($classes as $class => $path) {
    class_exists($class, true);
}

echo ' DONE' . PHP_EOL;

// resulting list of all includes and ordered class list
$files = array_merge($includes, $ordered);
echo 'Concatenating ' . count($files) . ' files into ' . $out . '...';
system('sed -n "/\#\!/,/^$/p" leproxy.php | sed -e "s/version dev/version ' . $version . '/" > ' . escapeshellarg($out));

foreach ($files as $file) {
    $file = substr($file, strlen(__DIR__) + 1);
    system('(echo "# ' . $file . '"; grep -v "<?php" ' . escapeshellarg($file) . ') >> ' . escapeshellarg($out));
}

$file = 'leproxy.php';
system('(echo "# ' . $file . '"; egrep -v "^<\?php|^\(@include " ' . escapeshellarg($file) . ') | sed -e "s/development/release/;/define(\'VERSION\'/c const VERSION=\"' . $version . '\";" >> ' . escapeshellarg($out));
chmod($out, 0755);
echo ' DONE (' . filesize($out) . ' bytes)' . PHP_EOL;

echo 'Optimizing resulting file...';
$small = '';
$all = token_get_all(file_get_contents($out));

// search next non-whitespace/non-comment token
$next = function ($i) use (&$all) {
    for ($i = $i + 1; !isset($all[$i]) || is_array($all[$i]) && ($all[$i][0] === T_COMMENT || $all[$i][0] === T_DOC_COMMENT || $all[$i][0] === T_WHITESPACE); ++$i);
    return $i;
};

// search previous non-whitespace/non-comment token
$prev = function ($i) use (&$all) {
    for ($i = $i -1; $i >= 0 && (!isset($all[$i]) || (is_array($all[$i]) && ($all[$i][0] === T_COMMENT || $all[$i][0] === T_DOC_COMMENT || $all[$i][0] === T_WHITESPACE))); --$i);
    return $i;
};

$first = true;
foreach ($all as $i => $token) {
    if (is_array($token) && ($token[0] === T_COMMENT || $token[0] === T_DOC_COMMENT)) {
        // remove all comments except first
        if ($first === true) {
            $first = false;
            continue;
        }
        unset($all[$i]);
    } elseif (is_array($token) && $token[0] === T_PUBLIC) {
        // get next non-whitespace token after `public` visibility
        $token = $all[$next($i)];

        if (is_array($token) && $token[0] === T_VARIABLE) {
            // use shorter variable notation `public $a` => `var $a`
            $all[$i] = array(T_VAR, 'var');
        } else {
            // remove unneeded public identifier `public static function a()` => `static function a()`
            unset($all[$i]);
        }
    } elseif (is_array($token) && $token[0] === T_LNUMBER) {
        // Use shorter integer notation `0x0F` => `15` and `011` => `9`.
        // Technically, hex codes may be shorter for very large ints, but adding
        // another 2 leading chars is rarely worth it.
        // Optimizing floats is not really worth it, as they have many special
        // cases, such as e-notation and we would lose types for `0.0` => `0`.
        $all[$i][1] = (string)intval($token[1], 0);
    } elseif (is_array($token) && $token[0] === T_NEW) {
        // remove unneeded parenthesis for constructors without args `new a();` => `new a;`
        // jump over next token (class name), then next must be open parenthesis, followed by closing
        $open = $next($next($i));
        $close = $next($open);
        if ($all[$open] === '(' && $all[$close] === ')') {
            unset($all[$open], $all[$close]);
        }
    } elseif (is_array($token) && $token[0] === T_STRING) {
        // replace certain functions with their shorter alias function name
        // http://php.net/manual/en/aliases.php
        static $replace = array(
            'implode' => 'join',
            'fwrite' => 'fputs',
            'array_key_exists' => 'key_exists',
            'current' => 'pos',
        );

        // check this has a replacement and "looks like" a function call
        // this works on a number of assumptions, such as not being aliased/namespaced
        if (isset($replace[$token[1]])) {
            $p = $all[$prev($i)];

            if ($all[$next($i)] === '(' && (!is_array($p) || !in_array($p[0], array(T_FUNCTION, T_OBJECT_OPERATOR, T_DOUBLE_COLON, T_NEW)))) {
                $all[$i][1] = $replace[$all[$i][1]];
            }
        }
    } elseif (is_array($token) && $token[0] === T_EXIT) {
        // replace `exit` with shorter alias `die`
        // it's a language construct, not a function (see above)
        $all[$i][1] = 'die';
    } elseif (is_array($token) && $token[0] === T_RETURN) {
        // replace `return null;` with `return;`
        $t = $next($i);
        if (is_array($all[$t]) && $all[$t][0] === T_STRING && $all[$t][1] === 'null' && $all[$next($t)] === ';') {
            unset($all[$t]);
        }
    }
}
$all = array_values($all);
foreach ($all as $i => $token) {
    if (is_array($token) && $token[0] === T_WHITESPACE) {
        if (strpos($token[1], "\n") !== false) {
            $token = strpos("()[]<>=+-*/%|,.:?!'\"\n", substr($small, -1)) === false ? "\n" : '';
        } else {
            $last = substr($small, -1);
            $next = isset($all[$i + 1]) ? substr(is_array($all[$i + 1]) ? $all[$i + 1][1] : $all[$i + 1], 0, 1) : ' ';

            $token = (strpos('()[]{}<>;=+-*/%&|,.:?!@\'"' . "\r\n", $last) !== false || strpos('()[]{}<>;=+-*/%&|,.:?!@\'"' . '\\$', $next) !== false) ? '' : ' ';
        }
    }

    $small .= isset($token[1]) ? $token[1] : $token;
}
file_put_contents($out, $small);
echo ' DONE (' . strlen($small) . ' bytes)' . PHP_EOL;