<?php
/**
 * DokuWiki Plugin base class
 *
 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
 * @author     Christopher Smith <chris@jalakai.co.uk>
 */

/**
 * Do not inherit directly from this class, instead inherit from the specialized
 * ones in lib/plugin
 */
class DokuWiki_Plugin {

  var $localised = false;        // set to true by setupLocale() after loading language dependent strings
  var $lang = array();           // array to hold language dependent strings, best accessed via ->getLang()
  var $configloaded = false;     // set to true by loadConfig() after loading plugin configuration variables
  var $conf = array();           // array to hold plugin settings, best accessed via ->getConf()

  /**
   * General Info
   *
   * Needs to return a associative array with the following values:
   *
   * author - Author of the plugin
   * email  - Email address to contact the author
   * date   - Last modified date of the plugin in YYYY-MM-DD format
   * name   - Name of the plugin
   * desc   - Short description of the plugin (Text only)
   * url    - Website with more information on the plugin (eg. syntax description)
   */
  function getInfo(){
    trigger_error('getInfo() not implemented in '.get_class($this), E_USER_WARNING);
  }

  // plugin introspection methods
  // extract from class name, format = <plugin type>_plugin_<name>[_<component name>]
  function getPluginType() { list($t) = explode('_', get_class($this), 2); return $t;  }
  function getPluginName() { list($t, $p, $n) = explode('_', get_class($this), 4); return $n; }
  function getPluginComponent() { list($t, $p, $n, $c) = explode('_', get_class($this), 4); return (isset($c)?$c:''); }

  // localisation methods
  /**
   * getLang($id)
   * use this function to access plugin language strings
   * to try to minimise unnecessary loading of the strings when the plugin doesn't require them
   * e.g. when info plugin is querying plugins for information about themselves.
   *
   * @param   $id     id of the string to be retrieved
   * @return  string  string in appropriate language or english if not available
   */
  function getLang($id) {
    if (!$this->localised) $this->setupLocale();

    return (isset($this->lang[$id]) ? $this->lang[$id] : '');
  }

  /**
   * locale_xhtml($id)
   *
   * retrieve a language dependent file and pass to xhtml renderer for display
   * plugin equivalent of p_locale_xhtml()
   *
   * @param   $id     id of language dependent wiki page
   * @return  string  parsed contents of the wiki page in xhtml format
   */
  function locale_xhtml($id) {
    return p_cached_output($this->localFN($id));
  }

  /**
   * localFN($id)
   * prepends appropriate path for a language dependent filename
   * plugin equivalent of localFN()
   */
  function localFN($id) {
    global $conf;
    $plugin = $this->getPluginName();
    $file = DOKU_PLUGIN.$plugin.'/lang/'.$conf['lang'].'/'.$id.'.txt';
    if(!@file_exists($file)){
      //fall back to english
      $file = DOKU_PLUGIN.$plugin.'/lang/en/'.$id.'.txt';
    }
    return $file;
  }

  /**
   *  setupLocale()
   *  reads all the plugins language dependent strings into $this->lang
   *  this function is automatically called by getLang()
   */
  function setupLocale() {
    if ($this->localised) return;

    global $conf;            // definitely don't invoke "global $lang"
    $path = DOKU_PLUGIN.$this->getPluginName().'/lang/';

    $lang = array();

    // don't include once, in case several plugin components require the same language file
    @include($path.'en/lang.php');
    if ($conf['lang'] != 'en') @include($path.$conf['lang'].'/lang.php');

    $this->lang = $lang;
    $this->localised = true;
  }

  // configuration methods
  /**
   * getConf($setting)
   *
   * use this function to access plugin configuration variables
   */
  function getConf($setting){

    if (!$this->configloaded){ $this->loadConfig(); }

    return $this->conf[$setting];
  }

  /**
   * loadConfig()
   * merges the plugin's default settings with any local settings
   * this function is automatically called through getConf()
   */
  function loadConfig(){
    global $conf;

    $defaults = $this->readDefaultSettings();
    $plugin = $this->getPluginName();

    foreach ($defaults as $key => $value) {
      if (isset($conf['plugin'][$plugin][$key])) continue;
      $conf['plugin'][$plugin][$key] = $value;
    }

    $this->configloaded = true;
    $this->conf =& $conf['plugin'][$plugin];
  }

  /**
   * read the plugin's default configuration settings from conf/default.php
   * this function is automatically called through getConf()
   *
   * @return    array    setting => value
   */
  function readDefaultSettings() {

    $path = DOKU_PLUGIN.$this->getPluginName().'/conf/';
    $conf = array();

    if (@file_exists($path.'default.php')) {
      include($path.'default.php');
    }

    return $conf;
  }

  /**
   * Loads a given helper plugin (if enabled)
   *
   * @author  Esther Brunner <wikidesign@gmail.com>
   *
   * @param   $name   name of plugin to load
   * @param   $msg    message to display in case the plugin is not available
   *
   * @return  object  helper plugin object
   */
  function loadHelper($name, $msg){
    if (!plugin_isdisabled($name)) $obj =& plugin_load('helper',$name);
    else $obj = NULL;
    if (is_null($obj) && $msg) msg("Helper plugin $name is not available or invalid.",-1);
    return $obj;
  }

  // standard functions for outputing email addresses and links
  // use these to avoid having to duplicate code to produce links in line with the installation configuration

  /**
   * email
   * standardised function to generate an email link according to obfuscation settings
   */
  function email($email, $name='', $class='', $more='') {
    if (!$email) return $name;
    $email = obfuscate($email);
    if (!$name) $name = $email;
    $class = "class='".($class ? $class : 'mail')."'";
    return "<a href='mailto:$email' $class title='$email' $more>$name</a>";
  }

  /**
   * external_link
   * standardised function to generate an external link according to conf settings
   */
  function external_link($link, $title='', $class='', $target='', $more='') {
    global $conf;

    $link = htmlentities($link);
    if (!$title) $title = $link;
    if (!$target) $target = $conf['target']['extern'];
    if ($conf['relnofollow']) $more .= ' rel="nofollow"';

    if ($class) $class = " class='$class'";
    if ($target) $target = " target='$target'";
    if ($more) $more = " ".trim($more);

    return "<a href='$link'$class$target$more>$title</a>";
  }

  /**
   * output text string through the parser, allows dokuwiki markup to be used
   * very ineffecient for small pieces of data - try not to use
   */
  function render($text, $format='xhtml') {
    return p_render($format, p_get_instructions($text),$info);
  }

  // deprecated functions
  function plugin_localFN($id) { return $this->localFN($id); }
  function plugin_locale_xhtml($id) { return $this->locale_xhtml($id); }
  function plugin_email($e, $n='', $c='', $m='') { return $this->email($e, $n, $c, $m); }
  function plugin_link($l, $t='', $c='', $to='', $m='') { return $this->external_link($l, $t, $c, $to, $m); }
  function plugin_render($t, $f='xhtml') { return $this->render($t, $f); }
}