<?php

class Option {
    
    var $default = false;

    function Option() {
        call_user_func_array(array($this, "__construct"), func_get_args());
    }

    function __construct($options=false) {
        list($this->short, $this->long) = array_slice($options, 0, 2);
        $this->help = (isset($options['help'])) ? $options['help'] : "";
        $this->action = (isset($options['action'])) ? $options['action']
            : "store";
        $this->dest = (isset($options['dest'])) ? $options['dest']
            : substr($this->long, 2);
        $this->type = (isset($options['type'])) ? $options['type']
            : 'string';
        $this->const = (isset($options['const'])) ? $options['const']
            : null;
        $this->default = (isset($options['default'])) ? $options['default']
            : null;
        $this->metavar = (isset($options['metavar'])) ? $options['metavar']
            : 'var';
    }

    function hasArg() {
        return $this->action != 'store_true'
            && $this->action != 'store_false';
    }

    function handleValue(&$destination, $args) {
        $nargs = 0;
        $value = array_shift($args);
        if ($value[0] == '-')
            $value = null;
        elseif ($value)
            $nargs = 1;
        switch ($this->action) {
            case 'store_true':
                $value = true;
                break;
            case 'store_false':
                $value = false;
                break;
            case 'store_const':
                $value = $this->const;
                break;
            case 'store':
            default:
                if ($this->type == 'int')
                    $value = (int)$value;
                break;
        }
        $destination[$this->dest] = $value;
        return $nargs;
    }

    function toString() {
        $short = explode(':', $this->short);
        $long = explode(':', $this->long);
        if ($this->nargs == '?')
            $switches = sprintf('    %s [%3$s], %s[=%3$s]', $short[0],
                $long[0], $this->metavar);
        elseif ($this->hasArg())
            $switches = sprintf('    %s %3$s, %s=%3$s', $short[0], $long[0],
                $this->metavar);
        else
            $switches = sprintf("    %s, %s", $short[0], $long[0]);
        $help = preg_replace('/\s+/', ' ', $this->help);
        if (strlen($switches) > 24)
            $help = "\n" . str_repeat(" ", 24) . $help;
        else
            $switches = str_pad($switches, 24);
        $help = wordwrap($help, 54, "\n" . str_repeat(" ", 24));
        return $switches . $help;
    }
}

class Module {

    var $options = array();
    var $arguments = array();
    var $prologue = "";
    var $epilog = "";
    var $usage = '$script [options] $args [arguments]';
    var $autohelp = true;

    function Module() {
        call_user_func_array(array($this, '__construct'), func_get_args());
    }

    function __construct() {
        $this->options['help'] = array("-h","--help",
            'action'=>'store_true',
            'help'=>"Display this help message");
        foreach ($this->options as &$opt)
            $opt = new Option($opt);
    }

    function showHelp() {
        if ($this->prologue)
            echo $this->prologue . "\n\n";

        echo "Usage:\n";
        global $argv;
        echo "    " . str_replace(
                array('$script', '$args'),
                array($argv[0], implode(' ', array_keys($this->arguments))),
            $this->usage) . "\n";

        ksort($this->options);
        if ($this->options) {
            echo "\nOptions:\n";
            foreach ($this->options as $name=>$opt)
                echo $opt->toString() . "\n";
        }

        if ($this->arguments) {
            echo "\nArguments:\n";
            foreach ($this->arguments as $name=>$help)
                echo $name . "\n    " . wordwrap(
                    preg_replace('/\s+/', ' ', $help), 76, "\n    ");
        }

        if ($this->epilog) {
            echo "\n\n";
            $epilog = preg_replace('/\s+/', ' ', $this->epilog);
            echo wordwrap($epilog, 76, "\n");
        }

        echo "\n";
    }

    function getOption($name, $default=false) {
        $this->parseOptions();
        if (isset($this->_options[$name]))
            return $this->_options[$name];
        else
            return $default;
    }

    function getArgument($name, $default=false) {
        $this->parseOptions();
        foreach (array_keys($this->arguments) as $idx=>$arg)
            if ($arg == $name && isset($this->_args[$idx]))
                return $this->_args[$idx];
        return $default;
    }

    function parseOptions() {
        if (is_array($this->_options))
            return;

        global $argv;
        list($this->_options, $this->_args) =
            $this->parseArgs(array_slice($argv, 1));

        foreach (array_keys($this->arguments) as $idx=>$name)
            if (!isset($this->_args[$idx]))
                $this->optionError($name . " is a required argument");

        if ($this->autohelp && $this->getOption('help')) {
            $this->showHelp();
            die();
        }
    }

    function optionError($error) {
        echo "Error: " . $error . "\n\n";
        $this->showHelp();
        die();
    }

    /* abstract */ function run() {
    }

    /* static */ function register($action, $class) {
        global $registered_modules;
        $registered_modules[$action] = new $class();
    }

    /* static */ function getInstance($action) {
        global $registered_modules;
        return $registered_modules[$action];
    }

    function parseArgs($argv) {
        $options = $args = array();
        $argv = array_slice($argv, 0);
        while ($arg = array_shift($argv)) {
            if (strpos($arg, '=') !== false) {
                list($arg, $value) = explode('=', $arg, 2);
                array_unshift($argv, $value);
            }
            $found = false;
            foreach ($this->options as $opt) {
                if ($opt->short == $arg || $opt->long == $arg) {
                    if ($opt->handleValue($options, $argv))
                        array_shift($argv);
                    $found = true;
                }
            }
            if (!$found && $arg[0] != '-')
                $args[] = $arg;
        }
        return array($options, $args);
    }
}

$registered_modules = array();

?>