<?php

namespace Code\Module;

use App;
use DOMDocument;
use DomXPath;
use Code\Web\Controller;
use Code\Lib\Activity;
use Code\Lib\ActivityStreams;
use Code\Lib\Libzot;
use Code\Lib\Channel;
use Code\Lib\Oembed;
use Code\Lib\Url;
use Code\Lib\System;
use Code\Lib as Zlib;
use Code\Extend\Hook;

require_once('include/security.php');

class Linkinfo extends Controller
{

    protected $ident;

    public function get()
    {

        logger('linkinfo: ' . print_r($_REQUEST, true), LOGGER_DEBUG);

        // Google/YouTube does User-agent sniffing and will send you bad data if
        // you don't supply a compatibility identifier in the UA string.
        
        $ident = System::get_project_name();
        $this->ident = "Mozilla/5.0 (compatible; $ident)";
    
        $text = null;
        $str_tags = '';
        $process_embed = true;
        $process_oembed = (($_GET['oembed']) ? true : false);
        $process_zotobj = true;

        if (local_channel()) {
            $saved_oembed = ((get_pconfig(local_channel(), 'system', 'linkinfo_embed', true)) ? true : false);
            if ($saved_oembed !== $process_oembed) {
                set_pconfig(local_channel(), 'system', 'linkinfo_embed', intval($process_oembed));
            }
        }

        $br = "\n";

        if (x($_GET, 'binurl')) {
            $url = trim(hex2bin($_GET['binurl']));
        } else {
            $url = trim($_GET['url']);
        }

        if (str_starts_with($url, '!')) {
            $process_embed = false;
            $url = substr($url, 1);
        }

        $url = strip_zids($url);

        if (str_starts_with($url, 'geo:')) {
            if ($process_embed) {
                echo $br . '[map=' . substr($url, 4) . ']' . $br;
            } else {
                echo $br . '[url]' . $url . '[/url]' . $br;
            }
            killme();
        }

        if (str_starts_with($url, 'tel:') || (is_phone_number($url) !== false)) {
            $phone = $url;
            if (!str_starts_with($url, 'tel:')) {
                $url = 'tel:' . is_phone_number($url);
            }
            echo $br . '[url=' . $url . ']' . $phone . '[/url]' . $br;
            killme();
        }

        $m = parse_url($url);

        if (!$m['scheme']) {
            if (strpos($url, '@')) {
                $xc = discover_resource($url);
                if ($xc) {
                    $x = q(
                        "select * from xchan where xchan_hash = '%s'",
                        dbesc($xc)
                    );
                    if ($x) {
                        $url = $x[0]['xchan_url'];
                    }
                } else {
                    echo $br . '[url=mailto:' . $url . ']' . $url . '[/url]' . $br;
                    killme();
                }
            } else {
                $url = 'http://' . $url;
            }
        }

        if ($_GET['title']) {
            $title = strip_tags(trim($_GET['title']));
        }

        if ($_GET['description']) {
            $text = strip_tags(trim($_GET['description']));
        }

        if ($_GET['tags']) {
            $arr_tags = str_getcsv($_GET['tags']);
            if (count($arr_tags)) {
                array_walk($arr_tags, 'self::arr_add_hashes');
                $str_tags = $br . implode(' ', $arr_tags) . $br;
            }
        }

        logger('linkinfo: ' . $url, LOGGER_DEBUG);

        $zrl = is_matrix_url($url);

        if (!$process_embed) {
            if ($zrl) {
                echo $br . '[zrl]' . $url . '[/zrl]' . $br;
            } else {
                echo $br . '[url]' . $url . '[/url]' . $br;
            }
            killme();
        }

        $result = Url::get($url, ['novalidate' => true, 'nobody' => true, 'useragent' => $this->ident]);
        if ($result['success']) {
            $hdrs = [];
            $h = explode("\n", $result['header']);
            foreach ($h as $l) {
                list($k, $v) = array_map("trim", explode(":", trim($l), 2));
                $hdrs[strtolower($k)] = $v;
            }
            if (array_key_exists('content-type', $hdrs)) {
                $type = $hdrs['content-type'];
            }
            if ($type) {
                if (stripos($type, 'image/') !== false) {
                    $basename = basename($url);

                    if ($zrl) {
                        echo $br . '[zmg alt="' . $basename . '"]' . $url . '[/zmg]' . $br;
                    } else {
                        echo $br . '[img alt="' . $basename . '"]' . $url . '[/img]' . $br;
                    }
                    killme();
                }
                if ((stripos($type, 'video/') !== false) || ($type === 'application/ogg')) {
                    $thumb = self::get_video_poster($url);
                    if ($thumb) {
                        if ($zrl) {
                            echo $br . '[zvideo poster=\'' . $thumb . '\']' . $url . '[/zvideo]' . $br;
                        } else {
                            echo $br . '[video poster=\'' . $thumb . '\']' . $url . '[/video]' . $br;
                        }
                        killme();
                    }
                    if ($zrl) {
                        echo $br . '[zvideo]' . $url . '[/zvideo]' . $br;
                    } else {
                        echo $br . '[video]' . $url . '[/video]' . $br;
                    }
                    killme();
                }
                if (stripos($type, 'audio/') !== false) {
                    if ($zrl) {
                        echo $br . '[zaudio]' . $url . '[/zaudio]' . $br;
                    } else {
                        echo $br . '[audio]' . $url . '[/audio]' . $br;
                    }
                    killme();
                }
                if (strtolower($type) === 'text/calendar') {
                    $content = Url::get($url, ['novalidate' => true, 'useragent' => $this->ident]);
                    if ($content['success']) {
                        $ev = ical_to_ev($content['body']);
                        if ($ev) {
                            echo $br . format_event_bbcode($ev[0]) . $br;
                            killme();
                        }
                    }
                }
                if (strtolower($type) === 'application/pdf' || strtolower($type) === 'application/x-pdf') {
                    echo $br . '[embed]' . $url . '[/embed]' . $br;
                    killme();
                }
            }
        }

        $template = $br . '[url=%s]%s[/url]%s' . $br;

        $arr = ['url' => $url, 'text' => ''];

        Hook::call('parse_link', $arr);

        if (strlen($arr['text'])) {
            echo $arr['text'];
            killme();
        }

        if ($process_zotobj) {
            $x = Activity::fetch($url, App::get_channel());
            $y = null;
            if (is_array($x)) {
                if (ActivityStreams::is_an_actor($x['type']) && $x['id']) {
                    if (check_siteallowed($x['id']) && check_channelallowed($x['id'])) {
                        $url = $x['url'];
                        if (is_array($url)) {
                            $url = $url[0]['href'];
                        }
                        $name = (($x['name']) ? $x['name'] . ' (' . $x['preferredUsername'] . ')' : $x['preferredUsername']);

                        if (array_path_exists('icon/url', $x)) {
                            $text = $br . $br . '[zrl=' . $url . '][zmg=300x300]' . $x['icon']['url'] . '[/zmg][/zrl]';
                        }
                        $text .= $br . $br . '[zrl=' . $url . ']' . $name . '[/zrl]' . $br . $br;
                        echo $text;
                        killme();
                    }
                } else {
                    $y = new ActivityStreams($x);
                    if (
                        $y->is_valid() && $y->type === 'Announce' && is_array($y->obj)
                        && array_key_exists('object', $y->obj) && array_key_exists('actor', $y->obj)
                    ) {
                        // This is a relayed/forwarded Activity (as opposed to a shared/boosted object)
                        // Reparse the encapsulated Activity and use that instead
                        logger('relayed activity', LOGGER_DEBUG);
                        $y = new ActivityStreams($y->obj);
                    }
                }

                if ($y && $y->is_valid()) {
                    $z = Activity::decode_note($y);
                    $r = q(
                        "select hubloc_hash, hubloc_network, hubloc_id_url, hubloc_url from hubloc where hubloc_deleted = 0 and ( hubloc_hash = '%s' OR hubloc_id_url = '%s') order by hubloc_id desc",
                        dbesc(is_array($y->actor) ? $y->actor['id'] : $y->actor),
                        dbesc(is_array($y->actor) ? $y->actor['id'] : $y->actor)
                    );

                    if ($r) {
                        $r = Libzot::zot_record_preferred($r);
                        if ($z) {
                            $z['author_xchan'] = $r['hubloc_hash'];
                        }
                    }
                    if ($z) {
                        // do not allow somebody to embed a post that was blocked by the site admin
                        // We *will* let them over-rule any blocks they created themselves
                        if (check_siteallowed($r['hubloc_id_url']) && check_channelallowed($z['author_xchan'])) {
                            $s = new Zlib\Share($z);
                            echo $s->bbcode();
                            echo "\n" . '[attachment]' . $z['mid'] . '[/attachment]' . "\n";
                            killme();
                        }
                    }
                }
            }
        }
        if ($process_oembed) {
            $x = Oembed::process($url);
            if ($x) {
                echo $x;
                killme();
            }
        }

        if ($url && $title && $text) {
            $text = $br . '[quote]' . trim($text) . '[/quote]' . $br;

            $title = str_replace(["\r", "\n"], ['', ''], $title);

            $result = sprintf($template, $url, ($title) ? $title : $url, $text) . $str_tags;

            logger('linkinfo (unparsed): returns: ' . $result);

            echo $result;
            killme();
        }

        $siteinfo = self::parseurl_getsiteinfo($url, $this->ident);

        // If the site uses this platform, use zrl rather than url so they get zids sent to them by default

        if (is_matrix_url($url)) {
            $template = str_replace('url', 'zrl', $template);
        }

        if ($siteinfo["title"] == "") {
            echo sprintf($template, $url, $url, '') . $str_tags;
            killme();
        } else {
            $text = $siteinfo["text"];
            $title = $siteinfo["title"];
        }

        $image = "";

        if (isset($siteinfo['images']) && is_array($siteinfo['images']) && count($siteinfo["images"])) {
            /* Execute below code only if image is present in siteinfo */

            $total_images = 0;
            $max_images = get_config('system', 'max_bookmark_images');
            if ($max_images === false) {
                $max_images = 2;
            } else {
                $max_images = intval($max_images);
            }

            foreach ($siteinfo["images"] as $imagedata) {
                if ($url) {
                    $image .= sprintf('[url=%s]', $url);
                }
                $image .= '[img=' . $imagedata["width"] . 'x' . $imagedata["height"] . ']' . $imagedata["src"] . '[/img]';
                if ($url) {
                    $image .= '[/url]';
                }
                $image .= "\n";
                $total_images++;
                if ($max_images && $max_images >= $total_images) {
                    break;
                }
            }
        }

        if (strlen($text)) {
            $text = $br . '[quote]' . trim($text) . '[/quote]' . $br;
        }

        if ($image) {
            $text = $br . $br . $image . $text;
        }
        $title = str_replace(["\r", "\n"], ['', ''], $title);

        $result = sprintf($template, $url, ($title) ? $title : $url, $text) . $str_tags;

        logger('linkinfo: returns: ' . $result, LOGGER_DEBUG);

        echo trim($result);
        killme();
    }


    public static function deletexnode($doc, $node)
    {
        $xpath = new DomXPath($doc);
        $list = $xpath->query("//" . $node);
        foreach ($list as $child) {
            $child->parentNode->removeChild($child);
        }
    }

    public static function completeurl($url, $scheme)
    {
        $urlarr = parse_url($url);

        if (isset($urlarr["scheme"])) {
            return ($url);
        }

        $schemearr = parse_url($scheme);

        $complete = $schemearr["scheme"] . "://" . $schemearr["host"];

        if ($schemearr["port"] != "") {
            $complete .= ":" . $schemearr["port"];
        }

        if (!str_starts_with($urlarr['path'], '/')) {
            $complete .= '/';
        }

        $complete .= $urlarr["path"];

        if ($urlarr["query"] != "") {
            $complete .= "?" . $urlarr["query"];
        }

        if ($urlarr["fragment"] != "") {
            $complete .= "#" . $urlarr["fragment"];
        }

        return ($complete);
    }

    public static function get_video_poster($url)
    {

        if (!str_contains($url, z_root() . '/cloud/')) {
            return EMPTY_STR;
        }
        $m = parse_url($url, PHP_URL_PATH);
        if ($m) {
            // strip leading '/cloud/'
            $m = substr($m, 7);
        }
        $nick = substr($m, 0, strpos($m, '/'));
        $p = substr($m, strpos($m, '/') + 1);

        // get the channel to check permissions

        $u = Channel::from_username($nick);

        if ($u && $p) {
            $sql_extra = permissions_sql(intval($u['channel_id']));

            $r = q(
                "select hash, content from attach where display_path = '%s' and uid = %d and os_storage = 1 $sql_extra limit 1",
                dbesc($p),
                intval($u['channel_id'])
            );
            if ($r) {
                $path = dbunescbin($r[0]['content']);
                if ($path && @file_exists($path . '.thumb')) {
                    return z_root() . '/poster/' . $nick . '/' . $r[0]['hash'];
                }
            }
        }
        return EMPTY_STR;
    }


    public static function parseurl_getsiteinfo($url, $ident)
    {
        $siteinfo = [];


        $result = Url::get($url, ['novalidate' => true, 'useragent' => $ident]);
        if (!$result['success']) {
            return $siteinfo;
        }

        $header = $result['header'];
        $body = $result['body'];

        // Check codepage in HTTP headers or HTML if not exist
        $cp = (preg_match('/Content-Type: text\/html; charset=(.+)\r\n/i', $header, $o) ? $o[1] : '');
        if (empty($cp)) {
            $cp = (preg_match('/meta.+content=["|\']text\/html; charset=([^"|\']+)/i', $body, $o) ? $o[1] : 'AUTO');
        }

        $body = mb_convert_encoding($body, 'UTF-8', $cp);
        $body = mb_convert_encoding($body, 'HTML-ENTITIES', "UTF-8");

		if (! $body) {
			return $siteinfo;
		}

		try {
		    $doc = new DOMDocument();
			$doc->loadHTML($body);
		} catch (\Exception $e) {
			return $siteinfo;
		}
		
        self::deletexnode($doc, 'style');
        self::deletexnode($doc, 'script');
        self::deletexnode($doc, 'option');
        self::deletexnode($doc, 'h1');
        self::deletexnode($doc, 'h2');
        self::deletexnode($doc, 'h3');
        self::deletexnode($doc, 'h4');
        self::deletexnode($doc, 'h5');
        self::deletexnode($doc, 'h6');
        self::deletexnode($doc, 'ol');
        self::deletexnode($doc, 'ul');

        $xpath = new DomXPath($doc);

        $list = $xpath->query("//title");
        foreach ($list as $node) {
            $siteinfo["title"] = html_entity_decode($node->nodeValue, ENT_QUOTES, "UTF-8");
        }

        $list = $xpath->query("//meta[@name]");
        foreach ($list as $node) {
            $attr = [];
            if ($node->attributes->length) {
                foreach ($node->attributes as $attribute) {
                    $attr[$attribute->name] = $attribute->value;
                }
            }

            $attr["content"] = html_entity_decode($attr["content"], ENT_QUOTES, "UTF-8");

            switch (strtolower($attr["name"])) {
                case "fulltitle":
                    $siteinfo["title"] = trim($attr["content"]);
                    break;
                case "description":
                    $siteinfo["text"] = trim($attr["content"]);
                    break;
                case "thumbnail":
                    $siteinfo["image"] = $attr["content"];
                    break;
                case "twitter:image":
                    $siteinfo["image"] = $attr["content"];
                    break;
                case "twitter:image:src":
                    $siteinfo["image"] = $attr["content"];
                    break;
                case "twitter:card":
                    if (($siteinfo["type"] == "") || ($attr["content"] == "photo")) {
                        $siteinfo["type"] = $attr["content"];
                    }
                    break;
                case "twitter:description":
                    $siteinfo["text"] = trim($attr["content"]);
                    break;
                case "twitter:title":
                    $siteinfo["title"] = trim($attr["content"]);
                    break;
                case "dc.title":
                    $siteinfo["title"] = trim($attr["content"]);
                    break;
                case "dc.description":
                    $siteinfo["text"] = trim($attr["content"]);
                    break;
                case "keywords":
                    $keywords = explode(",", $attr["content"]);
                    break;
                case "news_keywords":
                    $keywords = explode(",", $attr["content"]);
                    break;
            }
        }

        $list = $xpath->query("//meta[@property]");
        foreach ($list as $node) {
            $attr = [];
            if ($node->attributes->length) {
                foreach ($node->attributes as $attribute) {
                    $attr[$attribute->name] = $attribute->value;
                }
            }

            $attr["content"] = html_entity_decode($attr["content"], ENT_QUOTES, "UTF-8");

            switch (strtolower($attr["property"])) {
                case "og:image":
                    $siteinfo["image"] = $attr["content"];
                    break;
                case "og:title":
                    $siteinfo["title"] = $attr["content"];
                    break;
                case "og:description":
                    $siteinfo["text"] = $attr["content"];
                    break;
            }
        }

        if ($siteinfo["image"] == "") {
            $list = $xpath->query("//img[@src]");
            foreach ($list as $node) {
                $attr = [];
                if ($node->attributes->length) {
                    foreach ($node->attributes as $attribute) {
                        $attr[$attribute->name] = $attribute->value;
                    }
                }

                $src = self::completeurl($attr["src"], $url);
                $photodata = @getimagesize($src);

                if (($photodata) && ($photodata[0] > 150) and ($photodata[1] > 150)) {
                    if ($photodata[0] > 300) {
                        $photodata[1] = round($photodata[1] * (300 / $photodata[0]));
                        $photodata[0] = 300;
                    }
                    if ($photodata[1] > 300) {
                        $photodata[0] = round($photodata[0] * (300 / $photodata[1]));
                        $photodata[1] = 300;
                    }
                    $siteinfo["images"][] = ["src" => $src,
                        "width" => $photodata[0],
                        "height" => $photodata[1]];
                }
            }
        } else {
            $src = self::completeurl($siteinfo["image"], $url);

            unset($siteinfo["image"]);

            $photodata = @getimagesize($src);

            if (($photodata) && ($photodata[0] > 10) and ($photodata[1] > 10)) {
                $siteinfo["images"][] = ["src" => $src,
                    "width" => $photodata[0],
                    "height" => $photodata[1]];
            }
        }

        if ($siteinfo["text"] == "") {
            $text = "";

            $list = $xpath->query("//div[@class='article']");
            foreach ($list as $node) {
                if (strlen($node->nodeValue) > 40) {
                    $text .= " " . trim($node->nodeValue);
                }
            }

            if ($text == "") {
                $list = $xpath->query("//div[@class='content']");
                foreach ($list as $node) {
                    if (strlen($node->nodeValue) > 40) {
                        $text .= " " . trim($node->nodeValue);
                    }
                }
            }

            // If none text was found then take the paragraph content
            if ($text == "") {
                $list = $xpath->query("//p");
                foreach ($list as $node) {
                    if (strlen($node->nodeValue) > 40) {
                        $text .= " " . trim($node->nodeValue);
                    }
                }
            }

            if ($text != "") {
                $text = trim(str_replace(["\n", "\r"], [" ", " "], $text));

                while (strpos($text, "  ")) {
                    $text = trim(str_replace("  ", " ", $text));
                }

                $siteinfo["text"] = html_entity_decode(substr($text, 0, 350), ENT_QUOTES, "UTF-8") . '...';
            }
        }

        return ($siteinfo);
    }


    private static function arr_add_hashes(&$item, $k)
    {
        if (!str_starts_with($item, '#')) {
            $item = '#' . $item;
        }
    }
}