shaarli-plugin-shaargem/shaargem.php

<?php
/**
 * shaargem
 *
 * This plugin provides gemini support
 */

use Shaarli\Config\ConfigManager;
use Shaarli\Plugin\PluginManager;
use Shaarli\Render\TemplatePage;

/**
 * In the footer hook, there is a working example of a translation extension for Shaarli.
 *
 * The extension must be attached to a new translation domain (i.e. NOT 'shaarli').
 * Use case: any custom theme or non official plugin can use the translation system.
 *
 * See the documentation for more information.
 */
const EXT_TRANSLATION_DOMAIN = 'shaargem';

/*
 * This is not necessary, but it's easier if you don't want Poedit to mix up your translations.
 */
function shaargem_t($text, $nText = '', $nb = 1)
{
    return t($text, $nText, $nb, EXT_TRANSLATION_DOMAIN);
}

/**
 * Initialization function.
 * It will be called when the plugin is loaded.
 * This function can be used to return a list of initialization errors.
 *
 * @param $conf ConfigManager instance.
 *
 * @return array List of errors (optional).
 */
function shaargem_init($conf)
{
    if (! $conf->exists('translation.extensions.shaargem')) {
        // Custom translation with the domain 'shaargem'
        $conf->set('translation.extensions.shaargem', 'plugins/shaargem/languages/');
        $conf->write(true);
    }

    //$errors[] = 'This a shaargem init error.';
    return $errors;
}

/**
 * Hook render_editlink.
 *
 * Template placeholders:
 *   - field_plugin: add link fields after tags.
 *
 * @param array $data data passed to plugin
 *
 * @return array altered $data.
 */
function hook_shaargem_render_editlink($data)
{
    // fetch title only for gemini:// iris
    if (isset($data['link']['url'])) {
        if (strstr($data['link']['url'], "gemini://")) {
            if ($data['link']['title'] == '') {
                $data['link']['title'] = fetch_iri_title($data['link']['url']);
            }
        }
    }
    return $data;
}

/**
 * Hook savelink.
 *
 * Triggered when a link is save (new or edit).
 * All new links now contain a 'stuff' value.
 *
 * @param array $data contains the new link data.
 *
 * @return array altered $data.
 */
function hook_shaargem_save_link($data)
{
    // ugly hack to get scheme
    if (isset($_POST['lf_url'])) {
        if (strstr($_POST['lf_url'], "gemini://")) {
            $new_url = str_replace("http://", "gemini://", $data['url']);
            $data['url'] = $new_url;
        }
    }
    return $data;
}

/**
 * Hook render_linklist.
 *
 * Template placeholders:
 *   - action_plugin: next to 'private only' button.
 *   - plugin_start_zone: page start
 *   - plugin_end_zone: page end
 *   - link_plugin: icons below each links.
 *
 * Data:
 *   - _LOGGEDIN_: true/false
 *
 * @param array $data data passed to plugin
 *
 * @return array altered $data.
 */
function hook_shaargem_render_linklist($data)
{
    foreach ($data['links'] as &$value) {
        $value['description'] = preg_replace(',gemini://([\d\w\.\+\-@\:%._\~#=/]+),', '<a href="gemini://\1">gemini://\1</a>', $value['description']);
    }
    return $data;
}

/**
 * This function is never called, but contains translation calls for GNU gettext extraction.
 */
function shaargem_dummy_translation()
{
    // meta
    shaargem_t('Provides Gemini protocol support.');
}

/**
 * Find capsule's title
 */
function fetch_iri_title($iri)
{
    $ret = preg_match(",gemini://([\d\w\.\+\-@\:%._\~#=]+)/?,", $iri, $domain);
    static $redirect_counter = 0;
    if ($ret) {
        $stream_context = stream_context_create([ 'ssl' => [
            'verify_peer'       => false,
            'verify_peer_name'  => false,
            'allow_self_signed' => true,
            'verify_depth'      => 0 ]]);

        $fp = stream_socket_client("tls://".$domain[1].":1965", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $stream_context);

        if (!$fp) {
            error_log("[shaargem] $errstr ($errno)");
        } else {
            fwrite($fp, $iri."\r\n");
            $header = fgets($fp);
            $ret = preg_match(",^(\d\d) (.*)\r\n$,", $header, $headers);
            $status = $headers[1];
            $meta = $headers[2];
            $max_redirects = 10;

            error_log("[shaargem] status:".$status.", meta:".$meta);

            // status 1x cannot be handled by shaarli, but input field can be used as title
            if ($status[0] == 1) {
                return $meta;
            }
            // status 2x ok
            elseif ($status[0] == 2) {
                $nblines = 1;
                while ($line = fgets($fp)) {
                    $ret = preg_match(",# (.*),", $line, $title);
                    if ($title[0] or $nblines > 100) {
                        break;
                    }
                    $nblines++;
                }
            }
            // status 3x redirect
            elseif ($status[0] == 3 and $redirect_counter < $max_redirects) {
                $redirect_counter++;
                error_log("[shaargem] ".shaargem_t("Redirecting to")." ".$meta." (".$redirect_counter."/".$max_redirects.")");
                $title[1] = fetch_iri_title($meta);
            }
            // 4x 5x 6x are error statuses, should find a better way to display that
            elseif ($status[0] == 4) {
                return shaargem_t('Error').' '.$status.' ('.shaargem_t('TEMPORARY FAILURE').'): '.$meta;
            } elseif ($status[0] == 5) {
                return shaargem_t('Error').' '.$status.' ('.shaargem_t('PERMANENT FAILURE').'): '.$meta;
            } elseif ($status[0] == 6) {
                return shaargem_t('Error').' '.$status.' ('.shaargem_t('CLIENT CERTIFICATE REQUIRED').'): '.$meta;
            } else {
                return shaargem_t('Invalid response').': '.$header;
            }
            fclose($fp);
        }
        return $title[1];
    }
}