<?php

/*
 +-----------------------------------------------------------------------+
 | program/include/rcube_config.php                                      |
 |                                                                       |
 | This file is part of the RoundCube Webmail client                     |
 | Copyright (C) 2008-2009, RoundCube Dev. - Switzerland                 |
 | Licensed under the GNU GPL                                            |
 |                                                                       |
 | PURPOSE:                                                              |
 |   Class to read configuration settings                                |
 |                                                                       |
 +-----------------------------------------------------------------------+
 | Author: Thomas Bruederli <roundcube@gmail.com>                        |
 +-----------------------------------------------------------------------+

 $Id: $

*/

/**
 * Configuration class for RoundCube
 *
 * @package Core
 */
class rcube_config
{
  private $prop = array();
  private $errors = array();


  /**
   * Object constructor
   */
  public function __construct()
  {
    $this->load();
  }


  /**
   * Load config from local config file
   *
   * @todo Remove global $CONFIG
   */
  private function load()
  {
    // start output buffering, we don't need any output yet, 
    // it'll be cleared after reading of config files, etc.
    ob_start();
    
    // load main config file
    if (!$this->load_from_file(RCMAIL_CONFIG_DIR . '/main.inc.php'))
      $this->errors[] = 'main.inc.php was not found.';

    // load database config
    if (!$this->load_from_file(RCMAIL_CONFIG_DIR . '/db.inc.php'))
      $this->errors[] = 'db.inc.php was not found.';
    
    // load host-specific configuration
    $this->load_host_config();

    // set skin (with fallback to old 'skin_path' property)
    if (empty($this->prop['skin']) && !empty($this->prop['skin_path']))
      $this->prop['skin'] = str_replace('skins/', '', unslashify($this->prop['skin_path']));
    else if (empty($this->prop['skin']))
      $this->prop['skin'] = 'default';

    // fix paths
    $this->prop['log_dir'] = $this->prop['log_dir'] ? unslashify($this->prop['log_dir']) : INSTALL_PATH . 'logs';
    $this->prop['temp_dir'] = $this->prop['temp_dir'] ? unslashify($this->prop['temp_dir']) : INSTALL_PATH . 'temp';

    // fix default imap folders encoding
    foreach (array('drafts_mbox', 'junk_mbox', 'sent_mbox', 'trash_mbox') as $folder)
      $this->prop[$folder] = rcube_charset_convert($this->prop[$folder], RCMAIL_CHARSET, 'UTF7-IMAP');

    if (!empty($this->prop['default_imap_folders']))
      foreach ($this->prop['default_imap_folders'] as $n => $folder)
        $this->prop['default_imap_folders'][$n] = rcube_charset_convert($folder, RCMAIL_CHARSET, 'UTF7-IMAP');

    // set PHP error logging according to config
    if ($this->prop['debug_level'] & 1) {
      ini_set('log_errors', 1);

      if ($this->prop['log_driver'] == 'syslog') {
        ini_set('error_log', 'syslog');
      } else {
        ini_set('error_log', $this->prop['log_dir'].'/errors');
      }
    }
    if ($this->prop['debug_level'] & 4) {
      ini_set('display_errors', 1);
    }
    else {
      ini_set('display_errors', 0);
    }
    
    // clear output buffer
    ob_end_clean();

    // export config data
    $GLOBALS['CONFIG'] = &$this->prop;
  }
  
  
  /**
   * Load a host-specific config file if configured
   * This will merge the host specific configuration with the given one
   */
  private function load_host_config()
  {
    $fname = null;

    if (is_array($this->prop['include_host_config'])) {
      $fname = $this->prop['include_host_config'][$_SERVER['HTTP_HOST']];
    }
    else if (!empty($this->prop['include_host_config'])) {
      $fname = preg_replace('/[^a-z0-9\.\-_]/i', '', $_SERVER['HTTP_HOST']) . '.inc.php';
    }

    if ($fname) {
      $this->load_from_file(RCMAIL_CONFIG_DIR . '/' . $fname);
    }
  }
  
  
  /**
   * Read configuration from a file
   * and merge with the already stored config values
   *
   * @param string Full path to the config file to be loaded
   * @return booelan True on success, false on failure
   */
  public function load_from_file($fpath)
  {
    if (is_file($fpath) && is_readable($fpath)) {
      include($fpath);
      if (is_array($rcmail_config)) {
        $this->prop = array_merge($this->prop, $rcmail_config);
        return true;
      }
    }
    
    return false;
  }
  
  
  /**
   * Getter for a specific config parameter
   *
   * @param  string Parameter name
   * @param  mixed  Default value if not set
   * @return mixed  The requested config value
   */
  public function get($name, $def = null)
  {
    return isset($this->prop[$name]) ? $this->prop[$name] : $def;
  }
  
  
  /**
   * Setter for a config parameter
   *
   * @param string Parameter name
   * @param mixed  Parameter value
   */
  public function set($name, $value)
  {
    $this->prop[$name] = $value;
  }
  
  
  /**
   * Override config options with the given values (eg. user prefs)
   *
   * @param array Hash array with config props to merge over
   */
  public function merge($prefs)
  {
    $this->prop = array_merge($this->prop, $prefs);
  }
  
  
  /**
   * Getter for all config options
   *
   * @return array  Hash array containg all config properties
   */
  public function all()
  {
    return $this->prop;
  }

  /**
   * Return requested DES crypto key.
   *
   * @param string Crypto key name
   * @return string Crypto key
   */
  public function get_crypto_key($key)
  {
    // Bomb out if the requested key does not exist
    if (!array_key_exists($key, $this->prop))
    {
      raise_error(array(
        'code' => 500,
        'type' => 'php',
        'file' => __FILE__,
        'message' => "Request for unconfigured crypto key \"$key\""
      ), true, true);
    }
  
    $key = $this->prop[$key];
  
    // Bomb out if the configured key is not exactly 24 bytes long
    if (strlen($key) != 24)
    {
      raise_error(array(
        'code' => 500,
        'type' => 'php',
        'file' => __FILE__,
        'message' => "Configured crypto key \"$key\" is not exactly 24 bytes long"
      ), true, true);
    }

    return $key;
  }

  /**
   * Try to autodetect operating system and find the correct line endings
   *
   * @return string The appropriate mail header delimiter
   */
  public function header_delimiter()
  {
    // use the configured delimiter for headers
    if (!empty($this->prop['mail_header_delimiter']))
      return $this->prop['mail_header_delimiter'];
    else if (strtolower(substr(PHP_OS, 0, 3)) == 'win')
      return "\r\n";
    else if (strtolower(substr(PHP_OS, 0, 3)) == 'mac')
      return "\r\n";
    else
      return "\n";
  }

  
  
  /**
   * Return the mail domain configured for the given host
   *
   * @param string IMAP host
   * @return string Resolved SMTP host
   */
  public function mail_domain($host)
  {
    $domain = $host;
    
    if (is_array($this->prop['mail_domain'])) {
      if (isset($this->prop['mail_domain'][$host]))
        $domain = $this->prop['mail_domain'][$host];
    }
    else if (!empty($this->prop['mail_domain']))
      $domain = $this->prop['mail_domain'];
    
    return $domain;
  }
  
  
  /**
   * Getter for error state
   *
   * @return mixed Error message on error, False if no errors
   */
  public function get_error()
  {
    return empty($this->errors) ? false : join("\n", $this->errors);
  }


}