<?php
/**
 * Part of Linksys WRT3G tools
 *
 * PHP version 5
 *
 * @category Tools
 * @package  linksys-wrt3g-tools
 * @author   Christian Weiske <cweiske@cweiske.de>
 * @license  AGPL v3
 * @link     http://cweiske.de/linksys-wrt3g-tools.htm
 */
require_once 'Config.php';
require_once 'System/Folders.php';

/**
 * Loads and saves the router configuration data from a config file
 *
 * @category Tools
 * @package  linksys-wrt3g-tools
 * @author   Christian Weiske <cweiske@cweiske.de>
 * @license  AGPL v3
 * @link     http://cweiske.de/linksys-wrt3g-tools.htm
 */
class Wrt3g_Config
{
    /**
     * Router hostname/IP
     *
     * @var string
     */
    public $host;

    /**
     * Name of user with administration privileges
     *
     * @var string
     */
    public $user;

    /**
     * Password for $user
     *
     * @var string
     */
    public $password;

    /**
     * Object with a "log" method.
     *
     * @var Wrt3g
     */
    public $logger;


    /**
     * Create new instance
     *
     * @param object $logger Object with log() method
     */
    public function __construct($logger)
    {
        $this->logger = $logger;
    }


    /**
     * Loads the router data from config file and takes the $options
     * array into account when set, overwriting the config file values.
     *
     * Config values are loaded into class variables
     *
     * @param array $options Array of commandline options. Values used:
     *                       - host - Hostname/IP
     *                       - user - Username to log in with
     *                       - password - Password for user
     *
     * @return void
     */
    public function load($options = array())
    {
        //system config file
        $this->loadFromFile('/etc/linksys-wrt3g-tools');

        //user config file
        $file = $this->getConfigFilePath();
        if ($file) {
            $this->loadFromFile($file);
        }
        //environment variables: we use lowercase options, which should
        // not collide with the uppercase env variables like USER
        $this->loadOptions($_SERVER);
        //commandline options
        $this->loadOptions($options);

        $this->logger->log(
            sprintf(
                "Configuration: %s:%s@%s",
                $this->user, $this->password, $this->host
            ),
            2
        );

        $this->verify();

        if (isset($options['save'])) {
            $this->save($file);
        }
    }


    /**
     * Loads the options array from command line into the class
     * variables.
     *
     * @param array $options Array of commandline options. Values used:
     *                       - host - Hostname/IP
     *                       - user - Username to log in with
     *                       - password - Password for user
     *
     * @return void
     */
    protected function loadOptions($options)
    {
        foreach (array('host', 'user', 'password') as $variable) {
            if (isset($options[$variable])) {
                $this->$variable = $options[$variable];
            }
        }
    }


    /**
     * Loads configuration from config file ("ini" style).
     * The file does not need to exist. Config values are stored
     * in the public class variables.
     *
     * @param string $file Config file path to load
     *
     * @return void
     *
     * @throws Exception When something went wrong
     */
    protected function loadFromFile($file)
    {
        $this->logger->log('Trying to load config file ' . $file, 2);
        $cfg = new Config();
        $root = $cfg->parseConfig($file, 'inifile');

        if (PEAR::isError($root)) {
            $this->logger->log(
                'Error while reading configuration: ' . $root->getMessage(),
                1
            );
            return;
        }
        $settings = $root->toArray();
        $this->loadOptions($settings['root']);
    }


    /**
     * Returns the full path to the configuration file, if it exists
     * or not.
     *
     * @return string Config file path or NULL if not determinable
     */
    public function getConfigFilePath()
    {
        $sf = new System_Folders();
        $home = $sf->getHome();
        if ($home === null) {
            return null;
        }
        //works on linux only :)
        return $home . '.config/linksys-wrt3g-tools';
    }


    /**
     * Saves the config file
     *
     * @param string $file Config file path to save into
     *
     * @return void
     */
    public function save($file)
    {
        $cfg = new Config();
        $cfg->parseConfig($file, 'inifile');
        //ignore read errors

        $root = $cfg->getRoot();
        $root->setDirective('host', $this->host);
        $root->setDirective('user', $this->user);
        $root->setDirective('password', $this->password);
        
        $this->logger->log('Saving config into file ' . $file, 2);
        $cfg->writeConfig($file, 'inifile');
    }


    /**
     * Verifies that all required options are set
     *
     * @return void
     *
     * @throw Exception When something is missing
     */
    protected function verify()
    {
        if ($this->host == '') {
            throw new Exception('Hostname missing');
        }
    }
}

?>