<?php

namespace Code\Lib;

/**
 * @file Code\Lib\Channel.php
 * @brief Channel related functions.
 */

use App;
use Code\Entity\Channel as ChannelEntity;
use Code\Lib\Libzot;
use Code\Lib\Libsync;
use Code\Lib\AccessList;
use Code\Lib\Crypto;
use Code\Lib\Connect;
use Code\Lib\AbConfig;
use Code\Access\PermissionRoles;
use Code\Access\PermissionLimits;
use Code\Access\Permissions;
use Code\Daemon\Run;
use Code\Lib\System;
use Code\Lib\Url;
use Code\Render\Comanche;
use Code\Lib\ServiceClass;
use Code\Extend\Hook;
use Code\Render\Theme;


require_once('include/photo_factory.php');

require_once('include/security.php');

class Channel
{


    /**
     * @brief Determine if the channel name is allowed when creating a new channel.
     *
     * This action is pluggable.
     * We're currently only checking for an empty name or one that exceeds our
     * storage limit (256 chars). 256 chars is probably going to create a mess on
     * some pages.
     * Plugins can set additional policies such as full name requirements, character
     * sets, multi-byte length, etc.
     *
     * @param string $name
     * @return string describing the error state, or nil return if name is valid
     */
    public static function validate_channelname($name)
    {

        if (! $name) {
            return t('Empty name');
        }

        if (mb_strlen($name) > 256) {
            return t('Name too long');
        }

        $arr = ['name' => $name];
        /**
         * @hooks validate_channelname
         *   Used to validate the names used by a channel.
         *   * \e string \b name
         *   * \e string \b message - return error message
         */
        Hook::call('validate_channelname', $arr);

        if (x($arr, 'message')) {
            return $arr['message'];
        }
    }

    public static function getVapidKey()
    {
        $private_key = openssl_pkey_new([
            'private_key_type' => OPENSSL_KEYTYPE_EC,
            'curve_name' => 'prime256v1',
        ]);

        $details = openssl_pkey_get_details($private_key);
        $private_key_raw = $details['ec']['d'];
        $public_key_raw = $details['ec']['x'] . $details['ec']['y'];
        $auth_token = base64_encode(openssl_random_pseudo_bytes(16));

        $vapid = [
            'private_key' => rtrim(strtr(base64_encode($private_key_raw), '+/', '-_'), '='),
            'public_key' => rtrim(strtr(base64_encode($public_key_raw), '+/', '-_'), '='),
            'auth_token' => $auth_token,
        ];

        return json_encode($vapid);
    }

    public static function getApplicationServerKey($vapid)
    {
        $publicKey = $vapid['public_key'];
        $public_key_bytes = base64_decode($publicKey);

        // Check that the public key has the correct format
        if (strlen($public_key_bytes) != 65 || ord($public_key_bytes[0]) != 4) {
            // The public key has an incorrect format
            // Handle the error here
        }

        // Extract the x and y coordinates of the point
        $x = substr($public_key_bytes, 1, 32);
        $y = substr($public_key_bytes, 33, 32);

        // Pack the bytes of the public key in the correct order
        $application_server_key = "\x04" . $x . $y;
        return base64_encode($application_server_key);
    }

    /**
     * @brief Create a system channel - which has no account attached.
     *
     */
    public static function create_system()
    {

        // Ensure that there is a host keypair.

        if ((! get_config('system', 'pubkey')) || (! get_config('system', 'prvkey'))) {
            $hostkey = Crypto::new_keypair(4096);
            set_config('system', 'pubkey', $hostkey['pubkey']);
            set_config('system', 'prvkey', $hostkey['prvkey']);
        }

        $sys = self::get_system();

        if ($sys) {
            // upgrade the default network drivers and permissions if this looks like an upgraded zot6-based platform.

            if ($sys['xchan_network'] !== 'nomad') {
                $chans = q("select * from channel where true");
                if ($chans) {
                    foreach ($chans as $chan) {
                        q("update hubloc set hubloc_network = 'nomad' where hubloc_hash = '%s'",
                            dbesc($chan['channel_hash'])
                        );
                        q("update xchan set xchan_network = 'nomad' where xchan_hash = '%s'",
                            dbesc($chan['channel_hash'])
                        );
                    }
                }
                q("update xchan set xchan_hidden = 0, xchan_type = %d where xchan_hash = '%s'",
                    intval(XCHAN_TYPE_ORGANIZATION),
                    dbesc($sys['xchan_hash'])
                );

                // Add the new "deliver_stream" permission

                $c = q("select * from channel where true");
                if ($c) {
                    foreach ($c as $cv) {
                        PConfig::Set($cv['channel_id'],'perm_limits','deliver_stream', PERMS_SPECIFIC);
                    }
                }
                $ab = q("SELECT * from abook where abook_self = 0");
                if ($ab) {
                    foreach ($ab as $abv) {
                        $p = explode(',', AbConfig::Get($abv['abook_channel'], $abv['abook_xchan'], 'system', 'my_perms', EMPTY_STR));
                        if (! in_array('deliver_stream', $p)) {
                            $p[] = 'deliver_stream';
                        }
                        AbConfig::Set($abv['abook_channel'], $abv['abook_xchan'], 'system', 'my_perms', implode(',', $p));
                    }
                }
            }

            // fix lost system keys, since we cannot communicate without them

            if (!(isset($sys['channel_pubkey']) && $sys['channel_pubkey'] === get_config('system', 'pubkey'))) {
                // upgrade the sys channel and return
                $pubkey = get_config('system', 'pubkey');
                $prvkey = get_config('system', 'prvkey');
                $guid_sig = Libzot::sign($sys['channel_guid'], $prvkey);
                $hash = Libzot::make_xchan_hash($sys['channel_guid'], $pubkey);

                q(
                    "update channel set channel_guid_sig = '%s', channel_hash = '%s', channel_pubkey = '%s', channel_prvkey = '%s' where channel_id = %d",
                    dbesc($guid_sig),
                    dbesc($hash),
                    dbesc($pubkey),
                    dbesc($prvkey),
                    dbesc($sys['channel_id'])
                );

                q(
                    "update xchan set xchan_guid_sig = '%s', xchan_hash = '%s', xchan_pubkey = '%s', xchan_url = '%s' where xchan_hash = '%s'",
                    dbesc($guid_sig),
                    dbesc($hash),
                    dbesc($pubkey),
                    dbesc(z_root()),
                    dbesc($sys['channel_hash'])
                );
                q(
                    "update hubloc set hubloc_guid_sig = '%s', hubloc_hash = '%s', hubloc_id_url = '%s', hubloc_url_sig = '%s', hubloc_url = '%s', hubloc_callback = '%s', hubloc_site_id = '%s', hubloc_orphancheck = 0, hubloc_error = 0, hubloc_deleted = 0 where hubloc_hash = '%s'",
                    dbesc($guid_sig),
                    dbesc($hash),
                    dbesc(z_root()),
                    dbesc(Libzot::sign(z_root(), $prvkey)),
                    dbesc(z_root()),
                    dbesc(z_root() . '/nomad'),
                    dbesc(Libzot::make_xchan_hash(z_root(), $pubkey)),
                    dbesc($sys['channel_hash'])
                );

                q(
                    "update abook set abook_xchan = '%s' where abook_xchan = '%s'",
                    dbesc($hash),
                    dbesc($sys['channel_hash'])
                );

                q(
                    "update abconfig set xchan = '%s' where xchan = '%s'",
                    dbesc($hash),
                    dbesc($sys['channel_hash'])
                );

            }
            App::$sys_channel = $sys;
            return;
        }

        $basename = ucfirst(basename(z_root()));
        $sitename = substr($basename,0,strrpos($basename,'.'));

        self::create([
                'account_id'       => 'xxx',  // Typecast trickery: account_id is required. This will create an identity with an (integer) account_id of 0
                'nickname'         => 'sys',
                'name'             => $sitename,
                'permissions_role' => 'social',
                'pageflags'        => 0,
                'publish'          => 0,
                'system'           => 1
        ]);
    }


    /**
     * @brief Returns the sys channel.
     *
     * @return array|bool
     */
    public static function get_system()
    {

        // App::$sys_channel caches this lookup

        if (is_array(App::$sys_channel)) {
            return App::$sys_channel;
        }

        $r = q("select * from channel left join xchan on channel_hash = xchan_hash where channel_system = 1 limit 1");

        if ($r) {
            App::$sys_channel = array_shift($r);
            return App::$sys_channel;
        }
        return false;
    }


    /**
     * @brief Checks if $channel_id is sys channel.
     *
     * @param int $channel_id
     * @return bool
     */
    public static function is_system($channel_id)
    {
        $s = self::get_system();
        if ($s) {
            return (intval($s['channel_id']) === intval($channel_id));
        }
        return false;
    }


    /**
     * @brief Return the total number of channels on this site.
     *
     * No filtering is performed except to check channel_removed.
     *
     * @returns int|bool
     *   on error returns boolean false
     */
    public static function channel_total()
    {
        $r = q("select channel_id from channel where channel_removed = 0");

        if (is_array($r)) {
            return count($r);
        }

        return false;
    }


    /**
     * @brief Create a new channel.
     *
     * Also creates the related xchan, hubloc, profile, and "self" abook records,
     * and an empty "Friends" group/collection for the new channel.
     *
     * @param array $arr associative array with:
     *  * \e string \b name full name of channel
     *  * \e string \b nickname "email/url-compliant" nickname
     *  * \e int \b account_id to attach with this channel
     *  * [other identity fields as desired]
     *
     * @returns array
     *     'success' => boolean true or false
     *     'message' => optional error text if success is false
     *     'channel' => if successful the created channel array
     */
    public static function create($arr)
    {

        $ret = ['success' => false];

        if (! $arr['account_id']) {
            $ret['message'] = t('No account identifier');
            return $ret;
        }
        $ret = ServiceClass::identity_check_service_class($arr['account_id']);
        if (!$ret['success']) {
            return $ret;
        }
        // save this for auto_friending
        $total_identities = $ret['total_identities'];

        $nick = mb_strtolower(trim($arr['nickname']));
        if (! $nick) {
            $ret['message'] = t('Nickname is required.');
            return $ret;
        }

        $name = escape_tags($arr['name']);
        $pageflags = ((x($arr, 'pageflags')) ? intval($arr['pageflags']) : PAGE_NORMAL);
        $system = ((x($arr, 'system')) ? intval($arr['system']) : 0);
        $name_error = self::validate_channelname($arr['name']);
        if ($name_error) {
            $ret['message'] = $name_error;
            return $ret;
        }

        if ($nick === 'sys' && (! $system)) {
            $ret['message'] = t('Reserved nickname. Please choose another.');
            return $ret;
        }

        if (check_webbie([$nick]) !== $nick) {
            $ret['message'] = t('Nickname has unsupported characters or is already being used on this site.');
            return $ret;
        }

        $guid = Libzot::new_uid($nick);

        if ($system) {
            $key = [ 'pubkey' => get_config('system', 'pubkey'), 'prvkey' => get_config('system', 'prvkey') ];
        } else {
            $key = Crypto::new_keypair(4096);
        }
        $eckey = sodium_crypto_sign_keypair();
        $ekey['pubkey'] = sodium_bin2base64(sodium_crypto_sign_publickey($eckey),SODIUM_BASE64_VARIANT_ORIGINAL_NO_PADDING);
        $ekey['prvkey'] = sodium_bin2base64(sodium_crypto_sign_secretkey($eckey),SODIUM_BASE64_VARIANT_ORIGINAL_NO_PADDING);

        $sig = Libzot::sign($guid, $key['prvkey']);
        $hash = Libzot::make_xchan_hash($guid, $key['pubkey']);

        // Force a few things on the short term until we can provide a theme or app with choice

        $publish = 1;

        if (array_key_exists('publish', $arr)) {
            $publish = intval($arr['publish']);
        }

        $role_permissions = null;
        $parent_channel_hash = EMPTY_STR;

        if (array_key_exists('permissions_role', $arr) && $arr['permissions_role']) {
            $role_permissions = PermissionRoles::role_perms($arr['permissions_role']);
            if (isset($role_permissions['channel_type']) && $role_permissions['channel_type'] === 'collection') {
                $parent_channel_hash = $arr['parent_hash'];
            }
        }

        if ($role_permissions && array_key_exists('directory_publish', $role_permissions)) {
            $publish = intval($role_permissions['directory_publish']);
        }

        $xchannel_type = XCHAN_TYPE_PERSON ;
        if (str_contains($arr['permissions_role'], 'forum') || str_contains($arr['permissions_role'], 'group')) {
            $xchannel_type = XCHAN_TYPE_GROUP ;
        }
        if ($system) {
            $xchannel_type = XCHAN_TYPE_ORGANIZATION ;
        }

        $primary = true;

        if (array_key_exists('primary', $arr)) {
            $primary = intval($arr['primary']);
        }

        $expire = 0;

        $r = self::channel_store_lowlevel(
            (new ChannelEntity())
                ->setAccountId(intval($arr['account_id']))
                ->setPrimary(intval($primary))
                ->setName($name)
                ->setParent($parent_channel_hash)
                ->setAddress($nick)
                ->setGuid($guid)
                ->setGuidSig($sig)
                ->setHash($hash)
                ->setPrvkey($key['prvkey'])
                ->setPubkey($key['pubkey'])
                ->setEprvkey($ekey['prvkey'])
                ->setEpubkey($ekey['pubkey'])
                ->setPageflags(intval($pageflags))
                ->setSystem(intval($system))
                ->setExpireDays($expire)
                ->setTimezone(date_default_timezone_get())
                ->toArray()
        );

        $r = q(
            "select * from channel where channel_account_id = %d and channel_guid = '%s' limit 1",
            intval($arr['account_id']),
            dbesc($guid)
        );

        if (! $r) {
            $ret['message'] = t('Unable to retrieve created identity');
            return $ret;
        }

        $a = q(
            "select * from account where account_id = %d",
            intval($arr['account_id'])
        );

        $photo_type = null;

        $z = [
                'account' => $a[0],
                'channel' => $r[0],
                'photo_url' => ''
        ];
        /**
         * @hooks create_channel_photo
         *   * \e array \b account
         *   * \e array \b channel
         *   * \e string \b photo_url - Return value
         */
        Hook::call('create_channel_photo', $z);

        // The site channel gets the project logo as a profile photo.
        if ($arr['account_id'] === 'xxx') {
            $photo_type = import_channel_photo_from_url(z_root() . '/images/' . REPOSITORY_ID . '.png', 0, $r[0]['channel_id']);
        }
        elseif ($z['photo_url']) {
            $photo_type = import_channel_photo_from_url($z['photo_url'], $arr['account_id'], $r[0]['channel_id']);
        }

        if ($role_permissions && array_key_exists('limits', $role_permissions)) {
            $perm_limits = $role_permissions['limits'];
        } else {
            $perm_limits = site_default_perms();
        }

        foreach ($perm_limits as $p => $v) {
            PermissionLimits::Set($r[0]['channel_id'], $p, $v);
        }

        if ($role_permissions && array_key_exists('perms_auto', $role_permissions)) {
            set_pconfig($r[0]['channel_id'], 'system', 'autoperms', intval($role_permissions['perms_auto']));
        }

        $ret['channel'] = $r[0];

        if (intval($arr['account_id'])) {
            self::set_default($arr['account_id'], $ret['channel']['channel_id'], false);
        }

        // Create a verified hub location pointing to this site.

        $r = hubloc_store_lowlevel(
            [
                'hubloc_guid'     => $guid,
                'hubloc_guid_sig' => $sig,
                'hubloc_id_url'   => (($system) ? z_root() : Channel::url($ret['channel'])),
                'hubloc_hash'     => $hash,
                'hubloc_addr'     => self::get_webfinger($ret['channel']),
                'hubloc_primary'  => intval($primary),
                'hubloc_url'      => z_root(),
                'hubloc_url_sig'  => Libzot::sign(z_root(), $ret['channel']['channel_prvkey']),
                'hubloc_site_id'  => Libzot::make_xchan_hash(z_root(), get_config('system', 'pubkey')),
                'hubloc_host'     => App::get_hostname(),
                'hubloc_callback' => z_root() . '/nomad',
                'hubloc_sitekey'  => get_config('system', 'pubkey'),
                'hubloc_network'  => 'nomad',
                'hubloc_updated'  => datetime_convert()
            ]
        );
        if (! $r) {
            logger('Unable to store hub location');
        }

        $newuid = $ret['channel']['channel_id'];

        $r = xchan_store_lowlevel(
            [
                'xchan_hash'       => $hash,
                'xchan_guid'       => $guid,
                'xchan_guid_sig'   => $sig,
                'xchan_pubkey'     => $key['pubkey'],
                'xchan_photo_mimetype' => (($photo_type) ? $photo_type : 'image/png'),
                'xchan_photo_l'    => z_root() . "/photo/profile/l/{$newuid}",
                'xchan_photo_m'    => z_root() . "/photo/profile/m/{$newuid}",
                'xchan_photo_s'    => z_root() . "/photo/profile/s/{$newuid}",
                'xchan_addr'       => self::get_webfinger($ret['channel']),
                'xchan_url'        => (($system) ? z_root() : Channel::url($ret['channel'])),
                'xchan_follow'     => z_root() . '/follow?f=&url=%s',
                'xchan_connurl'    => z_root() . '/poco/' . $ret['channel']['channel_address'],
                'xchan_name'       => $ret['channel']['channel_name'],
                'xchan_network'    => 'nomad',
                'xchan_type'       => $xchannel_type,
                'xchan_updated'    => datetime_convert(),
                'xchan_photo_date' => datetime_convert(),
                'xchan_name_date'  => datetime_convert(),
                'xchan_system'     => $system
            ]
        );

        // Not checking return value.
        // It's ok for this to fail if it's an imported channel, and therefore the hash is a duplicate

        $r = self::profile_store_lowlevel(
            [
                'aid'          => intval($ret['channel']['channel_account_id']),
                'uid'          => intval($newuid),
                'profile_guid' => new_uuid(),
                'profile_name' => t('Default Profile'),
                'is_default'   => 1,
                'publish'      => $publish,
                'fullname'     => $ret['channel']['channel_name'],
                'photo'        => z_root() . "/photo/profile/l/{$newuid}",
                'thumb'        => z_root() . "/photo/profile/m/{$newuid}"
            ]
        );

        if ($role_permissions) {
            $myperms = ((array_key_exists('perms_connect', $role_permissions)) ? $role_permissions['perms_connect'] : [] );
        } else {
            $x = PermissionRoles::role_perms('social');
            $myperms = $x['perms_connect'];
        }

        $r = abook_store_lowlevel(
            [
                'abook_account'   => intval($ret['channel']['channel_account_id']),
                'abook_channel'   => intval($newuid),
                'abook_xchan'     => $hash,
                'abook_closeness' => 0,
                'abook_created'   => datetime_convert(),
                'abook_updated'   => datetime_convert(),
                'abook_self'      => 1
            ]
        );


        $x = Permissions::serialise(Permissions::FilledPerms($myperms));
        set_abconfig($newuid, $hash, 'system', 'my_perms', $x);

        if (intval($ret['channel']['channel_account_id'])) {
            // Save our permissions role so we can perhaps call it up and modify it later.

            if ($role_permissions) {
                set_pconfig($newuid, 'system', 'permissions_role', $arr['permissions_role']);
                if (array_key_exists('online', $role_permissions)) {
                    set_pconfig($newuid, 'system', 'hide_presence', 1 - intval($role_permissions['online']));
                }
                if (array_key_exists('perms_auto', $role_permissions)) {
                    $autoperms = intval($role_permissions['perms_auto']);
                    set_pconfig($newuid, 'system', 'autoperms', $autoperms);
                }
            }

            // Create a group with yourself as a member. This allows somebody to use it
            // right away as a default group for new contacts.

            $group_hash = AccessList::add($newuid, t('Friends'));
            if ($group_hash) {
                AccessList::member_add($newuid, t('Friends'), $ret['channel']['channel_hash']);
            }

            // if our role_permissions indicate that we're using a default collection ACL, add it.

            if (is_array($role_permissions) && $role_permissions['default_collection']) {
                $default_collection_str = '<' . 'connections:' . $ret['channel']['channel_hash'] . '>';
            }

            q(
                "update channel set channel_default_group = '%s', channel_allow_gid = '%s' where channel_id = %d",
                dbesc($group_hash ?? ''),
                dbesc($default_collection_str ?? ''),
                intval($newuid)
            );


            set_pconfig($ret['channel']['channel_id'], 'system', 'photo_path', '%Y/%Y-%m');
            set_pconfig($ret['channel']['channel_id'], 'system', 'attach_path', '%Y/%Y-%m');

            // If this channel has a parent, auto follow them.

            if ($parent_channel_hash) {
                $ch = self::from_hash($parent_channel_hash);
                if ($ch) {
                    self::connect_and_sync($ret['channel'], self::get_webfinger($ch), true);
                }
            }

            // auto-follow any of the hub's pre-configured channel choices.
            // Only do this if it's the first channel for this account;
            // otherwise it could get annoying. Don't make this list too big
            // or it will impact registration time.

            $accts = get_config('system', 'auto_follow');
            if (($accts) && (! $total_identities)) {
                if (! is_array($accts)) {
                    $accts = [$accts];
                }

                foreach ($accts as $acct) {
                    if (trim($acct)) {
                        $f = self::connect_and_sync($ret['channel'], trim($acct));
                        if ($f['success']) {
                            $can_view_stream = their_perms_contains($ret['channel']['channel_id'], $f['abook']['abook_xchan'], 'view_stream');

                            // If we can view their stream, pull in some posts

                            if (($can_view_stream) || ($f['abook']['xchan_network'] === 'rss')) {
                                Run::Summon([ 'Onepoll',$f['abook']['abook_id'] ]);
                            }
                        }
                    }
                }
            }

            /**
             * @hooks create_identity
             *   Called when creating a channel.
             *   * \e int - The UID of the created identity
             */

            Hook::call('create_identity', $newuid);

            Run::Summon([ 'Directory', $ret['channel']['channel_id'] ]);
        }

        $ret['success'] = true;
        return $ret;
    }


    public static function connect_and_sync($channel, $address, $sub_channel = false)
    {

        if ((! $channel) || (! $address)) {
            return false;
        }

        $f = Connect::connect($channel, $address, $sub_channel);
        if ($f['success']) {
            $clone = [];
            foreach ($f['abook'] as $k => $v) {
                if (str_starts_with($k, 'abook_')) {
                    $clone[$k] = $v;
                }
            }
            unset($clone['abook_id']);
            unset($clone['abook_account']);
            unset($clone['abook_channel']);

            $abconfig = load_abconfig($channel['channel_id'], $clone['abook_xchan']);
            if ($abconfig) {
                $clone['abconfig'] = $abconfig;
            }

            Libsync::build_sync_packet($channel['channel_id'], [ 'abook' => [ $clone ] ], true);
            return $f;
        }
        return false;
    }


    public static function change_channel_keys($channel)
    {

        $ret = ['success' => false];

        $stored = [];

        $key = Crypto::new_keypair(4096);

        $sig = Libzot::sign($channel['channel_guid'], $key['prvkey']);
        $hash = Libzot::make_xchan_hash($channel['channel_guid'], $channel['channel_pubkey']);

        $stored['old_guid']     = $channel['channel_guid'];
        $stored['old_guid_sig'] = $channel['channel_guid_sig'];
        $stored['old_key']      = $channel['channel_pubkey'];
        $stored['old_hash']     = $channel['channel_hash'];

        $stored['new_key']      = $key['pubkey'];
        $stored['new_sig']      = Libzot::sign($key['pubkey'], $channel['channel_prvkey']);

        // Save this info for the notifier to collect

        set_pconfig($channel['channel_id'], 'system', 'keychange', $stored);

        $r = q(
            "update channel set channel_prvkey = '%s', channel_pubkey = '%s', channel_guid_sig = '%s', channel_hash = '%s' where channel_id = %d",
            dbesc($key['prvkey']),
            dbesc($key['pubkey']),
            dbesc($sig),
            dbesc($hash),
            intval($channel['channel_id'])
        );
        if (! $r) {
            return $ret;
        }

        $r = q(
            "select * from channel where channel_id = %d",
            intval($channel['channel_id'])
        );

        if (! $r) {
            $ret['message'] = t('Unable to retrieve modified identity');
            return $ret;
        }

        $modified = $r[0];

        $h = q(
            "select * from hubloc where hubloc_hash = '%s' and hubloc_url = '%s' and hubloc_deleted = 0 ",
            dbesc($stored['old_hash']),
            dbesc(z_root())
        );

        if ($h) {
            foreach ($h as $hv) {
                $hv['hubloc_guid_sig'] = $sig;
                $hv['hubloc_hash']     = $hash;
                $hv['hubloc_url_sig']  = Libzot::sign(z_root(), $modified['channel_prvkey']);
                hubloc_store_lowlevel($hv);
            }
        }

        $x = q(
            "select * from xchan where xchan_hash = '%s' ",
            dbesc($stored['old_hash'])
        );

        $check = q(
            "select * from xchan where xchan_hash = '%s'",
            dbesc($hash)
        );

        if (($x) && (! $check)) {
            $oldxchan = $x[0];
            foreach ($x as $xv) {
                $xv['xchan_guid_sig']  = $sig;
                $xv['xchan_hash']      = $hash;
                $xv['xchan_pubkey']    = $key['pubkey'];
                $xv['xchan_updated']   = datetime_convert();
                xchan_store_lowlevel($xv);
                $newxchan = $xv;
            }
        }

        Libsync::build_sync_packet($channel['channel_id'], [ 'keychange' => $stored ]);

        $a = q(
            "select * from abook where abook_xchan = '%s' and abook_self = 1",
            dbesc($stored['old_hash'])
        );

        if ($a) {
            q(
                "update abook set abook_xchan = '%s' where abook_id = %d",
                dbesc($hash),
                intval($a[0]['abook_id'])
            );
        }

        xchan_change_key($oldxchan, $newxchan);

        Run::Summon([ 'Notifier', 'keychange', $channel['channel_id'] ]);

        $ret['success'] = true;
        return $ret;
    }

    public static function change_address($channel, $new_address)
    {

        $ret = ['success' => false];

        $old_address = $channel['channel_address'];

        if ($new_address === 'sys') {
            $ret['message'] = t('Reserved nickname. Please choose another.');
            return $ret;
        }

        if (check_webbie([$new_address]) !== $new_address) {
            $ret['message'] = t('Nickname has unsupported characters or is already being used on this site.');
            return $ret;
        }

        $r = q(
            "update channel set channel_address = '%s' where channel_id = %d",
            dbesc($new_address),
            intval($channel['channel_id'])
        );
        if (! $r) {
            return $ret;
        }

        $r = q(
            "select * from channel where channel_id = %d",
            intval($channel['channel_id'])
        );

        if (! $r) {
            $ret['message'] = t('Unable to retrieve modified identity');
            return $ret;
        }

        $r = q(
            "update xchan set xchan_addr = '%s' where xchan_hash = '%s'",
            dbesc($new_address . '@' . App::get_hostname()),
            dbesc($channel['channel_hash'])
        );

        $h = q(
            "select * from hubloc where hubloc_hash = '%s' and hubloc_url = '%s' and hubloc_deleted = 0 ",
            dbesc($channel['channel_hash']),
            dbesc(z_root())
        );

        if ($h) {
            foreach ($h as $hv) {
                if ($hv['hubloc_primary']) {
                    q(
                        "update hubloc set hubloc_primary = 0 where hubloc_id = %d",
                        intval($hv['hubloc_id'])
                    );
                }
                hubloc_delete($hv);
                unset($hv['hubloc_id']);
                $hv['hubloc_addr'] = $new_address . '@' . App::get_hostname();
                hubloc_store_lowlevel($hv);
            }
        }

        // fix apps which were stored with the actual name rather than a macro

        $r = q(
            "select * from app where app_channel = %d and app_system = 1",
            intval($channel['channel_id'])
        );
        if ($r) {
            foreach ($r as $rv) {
                $replace = preg_replace('/([\=\/])(' . $old_address . ')($|[\%\/])/ism', '$1' . $new_address . '$3', $rv['app_url']);
                if ($replace != $rv['app_url']) {
                    q(
                        "update app set app_url = '%s' where id = %d",
                        dbesc($replace),
                        intval($rv['id'])
                    );
                }
            }
        }

        Run::Summon([ 'Notifier', 'refresh_all', $channel['channel_id'] ]);

        $ret['success'] = true;
        return $ret;
    }


    /**
     * @brief Set default channel to be used on login.
     *
     * @param int $account_id
     *       login account
     * @param int $channel_id
     *       channel id to set as default for this account
     * @param bool $force (optional) default true
     *       - if true, set this default unconditionally
     *       - if $force is false only do this if there is no existing default
     */
    public static function set_default($account_id, $channel_id, $force = true)
    {
        $r = q(
            "select account_default_channel from account where account_id = %d limit 1",
            intval($account_id)
        );
        if ($r) {
            if ((intval($r[0]['account_default_channel']) == 0) || ($force)) {
                $r = q(
                    "update account set account_default_channel = %d where account_id = %d",
                    intval($channel_id),
                    intval($account_id)
                );
            }
        }
    }

    /**
     * @brief Return an array with default list of sections to export.
     *
     * @return array with default section names to export
     */
    public static function get_default_export_sections()
    {
        $sections = [
                'channel',
                'connections',
                'config',
                'apps',
                'chatrooms',
                'events'
        ];

        $cb = [ 'sections' => $sections ];
        /**
         * @hooks get_default_export_sections
         *   Called to get the default list of functional data groups to export in Channel::basic_export().
         *   * \e array \b sections - return value
         */
        Hook::call('get_default_export_sections', $cb);

        return $cb['sections'];
    }


    /**
     * @brief Create an array representing the important channel information
     * which would be necessary to create a nomadic identity clone. This includes
     * most channel resources and connection information with the exception of content.
     *
     * @param int $channel_id
     *     Channel_id to export
     * @param array $sections (optional)
     *     Which sections to include in the export, default see get_default_export_sections()
     * @return array
     *     See function for details
     */
    public static function basic_export($channel_id, $sections = null)
    {

        /*
         * basic channel export
         */

        if (! $sections) {
            $sections = self::get_default_export_sections();
        }

        $ret = [];

        // use constants here as otherwise we will have no idea if we can import from a site
        // with a non-standard platform and version.

        $ret['compatibility'] = [
            'project'     => REPOSITORY_ID,
            'codebase'    => 'zap',
            'schema'      => 'streams',
            'version'     => STD_VERSION,
            'database'    => DB_UPDATE_VERSION
        ];

        /*
         * Process channel information regardless of it is one of the sections desired
         * because we need the channel relocation information in all export files/streams.
         */

        $r = q(
            "select * from channel where channel_id = %d limit 1",
            intval($channel_id)
        );
        if ($r) {
            $ret['relocate'] = [ 'channel_address' => $r[0]['channel_address'], 'url' => z_root()];
            if (in_array('channel', $sections)) {
                $ret['channel'] = $r[0];
                unset($ret['channel']['channel_password']);
                unset($ret['channel']['channel_salt']);
            }
        }

        if (in_array('channel', $sections) || in_array('profile', $sections)) {
            $r = q(
                "select * from profile where uid = %d",
                intval($channel_id)
            );
            if ($r) {
                $ret['profile'] = $r;
            }

            $r = q(
                "select mimetype, content, os_storage from photo
    			where imgscale = 4 and photo_usage = %d and uid = %d limit 1",
                intval(PHOTO_PROFILE),
                intval($channel_id)
            );

            if ($r && $r[0]['content']) {
                $ret['photo'] = [
                    'type' => $r[0]['mimetype'],
                    'data' => (($r[0]['os_storage'])
                        ? base64url_encode(file_get_contents($r[0]['content'])) : base64url_encode(dbunescbin($r[0]['content'])))
                ];
            }
        }

        if (in_array('connections', $sections)) {
            $r = q(
                "select * from atoken where atoken_uid = %d",
                intval($channel_id)
            );
            if ($r) {
                $ret['atoken'] = $r;
            }

            $xchans = [];
            $r = q(
                "select * from abook where abook_channel = %d ",
                intval($channel_id)
            );
            if ($r) {
                $ret['abook'] = $r;

                for ($x = 0; $x < count($ret['abook']); $x++) {
                    $xchans[] = $ret['abook'][$x]['abook_xchan'];
                    $abconfig = load_abconfig($channel_id, $ret['abook'][$x]['abook_xchan']);
                    if ($abconfig) {
                        $ret['abook'][$x]['abconfig'] = $abconfig;
                    }
                }
                stringify_array_elms($xchans);
            }

            if ($xchans) {
                $r = q("select * from xchan where xchan_hash in ( " . implode(',', $xchans) . " ) ");
                if ($r) {
                    $ret['xchan'] = $r;
                }

                $r = q("select * from hubloc where hubloc_hash in ( " . implode(',', $xchans) . " ) and hubloc_deleted = 0");
                if ($r) {
                    $ret['hubloc'] = $r;
                }
            }

            $r = q(
                "select * from pgrp where uid = %d ",
                intval($channel_id)
            );

            if ($r) {
                $ret['group'] = $r;
            }

            $r = q(
                "select * from pgrp_member where uid = %d ",
                intval($channel_id)
            );
            if ($r) {
                $ret['group_member'] = $r;
            }

            $r = q(
                "select * from xign where uid = %d ",
                intval($channel_id)
            );
            if ($r) {
                $ret['xign'] = $r;
            }

            $r = q(
                "select * from block where block_channel_id = %d ",
                intval($channel_id)
            );
            if ($r) {
                $ret['block'] = $r;
            }
        }

        if (in_array('config', $sections)) {
            $r = q(
                "select * from pconfig where uid = %d",
                intval($channel_id)
            );
            if ($r) {
                $ret['config'] = $r;
            }

            // All other term types will be included in items, if requested.

            $r = q(
                "select * from term where ttype in (%d,%d) and uid = %d",
                intval(TERM_SAVEDSEARCH),
                intval(TERM_THING),
                intval($channel_id)
            );
            if ($r) {
                $ret['term'] = $r;
            }
            // add psuedo-column obj_baseurl to aid in relocations

            $r = q(
                "select obj.*, '%s' as obj_baseurl from obj where obj_channel = %d",
                dbesc(z_root()),
                intval($channel_id)
            );

            if ($r) {
                $ret['obj'] = $r;
            }

            $r = q(
                "select * from likes where channel_id = %d",
                intval($channel_id)
            );

            if ($r) {
                $ret['likes'] = $r;
            }
        }

        if (in_array('apps', $sections)) {
            $r = q(
                "select * from app where app_channel = %d and app_system = 0",
                intval($channel_id)
            );
            if ($r) {
                for ($x = 0; $x < count($r); $x++) {
                    $r[$x]['term'] = q(
                        "select * from term where otype = %d and oid = %d",
                        intval(TERM_OBJ_APP),
                        intval($r[$x]['id'])
                    );
                }
                $ret['app'] = $r;
            }
            $r = q(
                "select * from app where app_channel = %d and app_system = 1",
                intval($channel_id)
            );
            if ($r) {
                for ($x = 0; $x < count($r); $x++) {
                    $r[$x]['term'] = q(
                        "select * from term where otype = %d and oid = %d",
                        intval(TERM_OBJ_APP),
                        intval($r[$x]['id'])
                    );
                }
                $ret['sysapp'] = $r;
            }
        }

        if (in_array('chatrooms', $sections)) {
            $r = q(
                "select * from chatroom where cr_uid = %d",
                intval($channel_id)
            );
            if ($r) {
                $ret['chatroom'] = $r;
            }
        }

        if (in_array('events', $sections)) {
            $r = q(
                "select * from event where uid = %d",
                intval($channel_id)
            );
            if ($r) {
                $ret['event'] = $r;
            }

            $r = q(
                "select * from item where resource_type = 'event' and uid = %d",
                intval($channel_id)
            );
            if ($r) {
                $ret['event_item'] = [];
                xchan_query($r);
                $r = fetch_post_tags($r);
                foreach ($r as $rr) {
                    $ret['event_item'][] = encode_item($rr, true);
                }
            }
        }

        if (in_array('items', $sections)) {
            /** @warning this may run into memory limits on smaller systems */

            /** export three months of posts. If you want to export and import all posts you have to start with
             * the first year and export/import them in ascending order.
             *
             * Don't export linked resource items. we'll have to pull those out separately.
             */

            $r = q(
                "select * from item where item_wall = 1 and item_deleted = 0 and uid = %d
    			and created > %s - INTERVAL %s and resource_type = '' order by created",
                intval($channel_id),
                db_utcnow(),
                db_quoteinterval('3 MONTH')
            );
            if ($r) {
                $ret['item'] = [];
                xchan_query($r);
                $r = fetch_post_tags($r);
                foreach ($r as $rr) {
                    $ret['item'][] = encode_item($rr, true);
                }
            }
        }

        $addon = [
                'channel_id' => $channel_id,
                'sections' => $sections,
                'data' => $ret
        ];
        /**
         * @hooks identity_basic_export
         *   Called when exporting a channel's basic information for backup or transfer.
         *   * \e number \b channel_id - The channel ID
         *   * \e array \b sections
         *   * \e array \b data - The data will get returned
         */
        Hook::call('identity_basic_export', $addon);
        $ret = $addon['data'];

        return $ret;
    }

    /**
     * @brief Export items for a year, or a month of a year.
     *
     * @param int $channel_id The channel ID
     * @param number $year YYYY
     * @param number $month (optional) 0-12, default 0 complete year
     * @return array An associative array
     *   * \e array \b relocate - (optional)
     *   * \e array \b item - array with items encoded_item()
     */
    public static function export_year($channel_id, $year, $month = 0)
    {

        if (! $year) {
            return [];
        }

        if ($month && $month <= 12) {
            $target_month = sprintf('%02d', $month);
            $target_month_plus = sprintf('%02d', $month + 1);
        } else {
            $target_month = '01';
        }

        $mindate = datetime_convert('UTC', 'UTC', $year . '-' . $target_month . '-01 00:00:00');
        if ($month && $month < 12) {
            $maxdate = datetime_convert('UTC', 'UTC', $year . '-' . $target_month_plus . '-01 00:00:00');
        } else {
            $maxdate = datetime_convert('UTC', 'UTC', $year + 1 . '-01-01 00:00:00');
        }

        return self::export_items_date($channel_id, $mindate, $maxdate);
    }

    /**
     * @brief Export items within an arbitrary date range.
     *
     * Date/time is in UTC.
     *
     * @param int $channel_id The channel ID
     * @param string $start
     * @param string $finish
     * @return array
     */

    public static function export_items_date($channel_id, $start, $finish)
    {

        if (! $start) {
            return [];
        } else {
            $start = datetime_convert('UTC', 'UTC', $start);
        }

        $finish = datetime_convert('UTC', 'UTC', (($finish) ? $finish : 'now'));
        if ($finish < $start) {
            return [];
        }

        $ret = [];

        $ch = self::from_id($channel_id);
        if ($ch) {
            $ret['relocate'] = [ 'channel_address' => $ch['channel_address'], 'url' => z_root()];
        }

        $ret['compatibility']['codebase'] = 'zap';
        $ret['compatibility']['schema'] = 'streams';

        $r = q(
            "select * from item where ( item_wall = 1 or item_type != %d ) and item_deleted = 0 and uid = %d and created >= '%s' and created <= '%s'  and resource_type = '' order by created",
            intval(ITEM_TYPE_POST),
            intval($channel_id),
            dbesc($start),
            dbesc($finish)
        );

        if ($r) {
            $ret['item'] = [];
            xchan_query($r);
            $r = fetch_post_tags($r);
            foreach ($r as $rr) {
                $ret['item'][] = encode_item($rr, true);
            }
        }

        return $ret;
    }


    /**
     * @brief Export items with pagination
     *
     *
     * @param int $channel_id The channel ID
     * @param int $page
     * @param int $limit (default 50)
     * @return array
     */

    public static function export_items_page($channel_id, $start, $finish, $page = 0, $limit = 50)
    {

        if (intval($page) < 1) {
            $page = 0;
        }

        if (intval($limit) < 1) {
            $limit = 1;
        }

        if (intval($limit) > 5000) {
            $limit = 5000;
        }

        if (! $start) {
            $start = NULL_DATE;
        } else {
            $start = datetime_convert('UTC', 'UTC', $start);
        }

        $finish = datetime_convert('UTC', 'UTC', (($finish) ? $finish : 'now'));
        if ($finish < $start) {
            return [];
        }

        $offset = intval($limit) * intval($page);

        $ret = [];

        $ch = self::from_id($channel_id);
        if ($ch) {
            $ret['relocate'] = [ 'channel_address' => $ch['channel_address'], 'url' => z_root()];
        }

        $ret['compatibility']['codebase'] = 'zap';
        $ret['compatibility']['schema'] = 'streams';


        $r = q(
            "select * from item where ( item_wall = 1 or item_type != %d ) and item_deleted = 0 and uid = %d and resource_type = '' and created >= '%s' and created <= '%s' order by created limit %d offset %d",
            intval(ITEM_TYPE_POST),
            intval($channel_id),
            dbesc($start),
            dbesc($finish),
            intval($limit),
            intval($offset)
        );

        if ($r) {
            $ret['item'] = [];
            xchan_query($r);
            $r = fetch_post_tags($r);
            foreach ($r as $rr) {
                $ret['item'][] = encode_item($rr, true);
            }
        }

        return $ret;
    }


    public static function get_my_url()
    {
        if (x($_SESSION, 'zrl_override')) {
            return $_SESSION['zrl_override'];
        }
        if (x($_SESSION, 'my_url')) {
            return $_SESSION['my_url'];
        }

        return false;
    }

    public static function get_my_address()
    {
        if (x($_SESSION, 'zid_override')) {
            return $_SESSION['zid_override'];
        }
        if (x($_SESSION, 'my_address')) {
            return $_SESSION['my_address'];
        }

        return false;
    }

    /**
     * @brief Add visitor's zid to our xchan and attempt authentication.
     *
     * If somebody arrives at our site using a zid, add their xchan to our DB if we
     * don't have it already.
     * And if they aren't already authenticated here, attempt reverse magic auth.
     */
    public static function zid_init()
    {
        $tmp_str = self::get_my_address();
        if (validate_email($tmp_str)) {
            $arr = [
                    'zid' => $tmp_str,
                    'url' => App::$cmd
            ];
            /**
            * @hooks zid_init
            *   * \e string \b zid - their zid
            *   * \e string \b url - the destination url
            */
            Hook::call('zid_init', $arr);

            if (! local_channel()) {
                $r = q(
                    "select * from hubloc where hubloc_addr = '%s' and hubloc_deleted = 0 order by hubloc_id desc limit 1",
                    dbesc($tmp_str)
                );
                if (! $r) {
                    Run::Summon([ 'Gprobe', $tmp_str]);
                }
                if ($r && remote_channel() && remote_channel() === $r[0]['hubloc_hash']) {
                    return;
                }

                logger('Not authenticated. Invoking reverse magic-auth for ' . $tmp_str);
                // try to avoid recursion - but send them home to do a proper magic auth
                $query = App::$query_string;
                $query = str_replace(['?zid=','&zid='], ['?rzid=','&rzid='], $query);
                $dest = '/' . $query;
                if ($r && ($r[0]['hubloc_url'] != z_root()) && (!str_contains($dest, '/magic')) && (!str_contains($dest, '/rmagic'))) {
                    goaway($r[0]['hubloc_url'] . '/magic' . '?f=&rev=1&owa=1&bdest=' . bin2hex(z_root() . $dest));
                } else {
                    logger(sprintf('No hubloc found for \'%s\'.', $tmp_str));
                }
            }
        }
    }

    /**
     * @brief If somebody arrives at our site using a zat, authenticate them.
     *
     */
    public static function zat_init()
    {
        if (local_channel() || remote_channel()) {
            return;
        }

        $r = q(
            "select * from atoken where atoken_token = '%s' limit 1",
            dbesc($_REQUEST['zat'])
        );
        if ($r) {
            $xchan = atoken_xchan($r[0]);
            atoken_login($xchan);
        }
    }

    public static function atoken_delete_and_sync($channel_id, $atoken_guid)
    {
        $r = q(
            "select * from atoken where atoken_guid = '%s' and atoken_uid = %d",
            dbesc($atoken_guid),
            intval($channel_id)
        );
        if ($r) {
            $atok = array_shift($r);
            $atok['deleted'] = true;
            atoken_delete($atok['atoken_id']);
            Libsync::build_sync_packet($channel_id, [ 'atoken' => [ $atok ] ]);
        }
    }

    /**
     * @brief Used from within PCSS themes to set theme parameters.
     *
     * If there's a puid request variable, that is the "page owner" and normally
     * their theme settings take precedence; unless a local user sets the "always_my_theme"
     * system pconfig, which means they don't want to see anybody else's theme
     * settings except their own while on this site.
     *
     * @return int
     */
    public static function get_theme_uid()
    {
        $uid = ((isset($_REQUEST['puid'])) ? intval($_REQUEST['puid']) : 0);
        if (local_channel()) {
            if ((get_pconfig(local_channel(), 'system', 'always_my_theme')) || (! $uid)) {
                return local_channel();
            }
        }
        if (! $uid) {
            $x = self::get_system();
            if ($x) {
                return $x['channel_id'];
            }
        }

        return $uid;
    }

    /**
    * @brief Retrieves the path of the default_profile_photo for this system
    * with the specified size.
    *
    * @param int $size (optional) default 300
    *   one of (300, 80, 48)
    * @return string with path to profile photo
    */
    public static function get_default_profile_photo($size = 300)
    {
        $scheme = get_config('system', 'default_profile_photo', DEFAULT_PROFILE_PHOTO);

        if (! is_dir('images/default_profile_photos/' . $scheme)) {
            $x = [ 'scheme' => $scheme, 'size' => $size, 'url' => '' ];
            Hook::call('default_profile_photo', $x);
            if ($x['url']) {
                return $x['url'];
            } else {
                $scheme = DEFAULT_PROFILE_PHOTO;
            }
        }

        return 'images/default_profile_photos/' . $scheme . '/' . $size . '.png';
    }

    public static function get_default_cover_photo($size) {
        $default_cover = get_config('system', 'default_cover_photo', DEFAULT_COVER_PHOTO);
        return 'images/default_cover_photos/' . $default_cover . '/' . $size . '.jpg';
    }


    /**
     * @brief Test whether a given identity is NOT a member of the Hubzilla.
     *
     * @param string $s
     *    xchan_hash of the identity in question
     * @return bool true or false
     */
    public static function is_foreigner($s)
    {
        return((strpbrk($s, '.:@')) ? true : false);
    }

    /**
     * @brief Test whether a given identity is a member of the Hubzilla.
     *
     * @param string $s
     *    xchan_hash of the identity in question
     * @return bool true or false
     */
    public static function is_member($s)
    {
        return((self::is_foreigner($s)) ? false : true);
    }

    /**
     * @brief Get chatpresence status for nick.
     *
     * @param string $nick
     * @return array An associative array with
     *   * \e bool \b result
     */
    public static function get_online_status($nick)
    {

        $ret = ['result' => false];

        $r = q(
            "select channel_id, channel_hash from channel where channel_address = '%s' limit 1",
            dbesc($nick)
        );
        if ($r) {
            $hide = get_pconfig($r[0]['channel_id'], 'system', 'hide_online_status');
            if ($hide) {
                return $ret;
            }
            $x = q(
                "select cp_status from chatpresence where cp_xchan = '%s' and cp_room = 0 limit 1",
                dbesc($r[0]['channel_hash'])
            );
            if ($x) {
                $ret['result'] = $x[0]['cp_status'];
            }
        }

        return $ret;
    }


    /**
     * @brief
     *
     * @param string $webbie
     * @return array|bool|string
     */
    public static function remote_online_status($webbie)
    {

        $result = false;
        $r = q(
            "select * from hubloc where hubloc_addr = '%s' and hubloc_deleted = 0 order by hubloc_id desc limit 1",
            dbesc($webbie)
        );
        if (! $r) {
            return $result;
        }
        $url = $r[0]['hubloc_url'] . '/online/' . substr($webbie, 0, strpos($webbie, '@'));

        $x = Url::get($url);
        if ($x['success']) {
            $j = json_decode($x['body'], true);
            if ($j) {
                $result = (($j['result']) ? $j['result'] : false);
            }
        }

        return $result;
    }


    /**
     * @brief Return the parsed identity selector HTML template.
     *
     * @return string with parsed HTML channel_id_selet template
     */
    public static function identity_selector()
    {
        if (local_channel()) {
            $r = q(
                "select channel.*, xchan.* from channel left join xchan on channel.channel_hash = xchan.xchan_hash where channel.channel_account_id = %d and channel_removed = 0 order by channel_name ",
                intval(get_account_id())
            );
            if ($r && count($r) > 1) {
                $o = replace_macros(Theme::get_template('channel_id_select.tpl'), [
                    '$channels' => $r,
                    '$selected' => local_channel()
                ]);

                return $o;
            }
        }

        return '';
    }


    public static function is_public_profile()
    {
        if (! local_channel()) {
            return false;
        }

        $channel = App::get_channel();
        if ($channel) {
            $perm = PermissionLimits::Get($channel['channel_id'], 'view_profile');
            if ($perm == PERMS_PUBLIC) {
                return true;
            }
        }

        return false;
    }

    public static function get_profile_fields_basic($filter = 0)
    {

        $profile_fields_basic = (($filter == 0) ? get_config('system', 'profile_fields_basic') : null);

        if (! $profile_fields_basic) {
            $profile_fields_basic = ['fullname','pdesc','chandesc','basic_gender','pronouns','dob','dob_tz','region','country_name','marital','sexual','homepage','hometown','keywords','about','contact'];
        }

        $x = [];
        if ($profile_fields_basic) {
            foreach ($profile_fields_basic as $f) {
                $x[$f] = 1;
            }
        }

        return $x;
    }


    public static function get_profile_fields_advanced($filter = 0)
    {
        $basic = self::get_profile_fields_basic($filter);
        $profile_fields_advanced = (($filter == 0) ? get_config('system', 'profile_fields_advanced') : null);
        if (! $profile_fields_advanced) {
            $profile_fields_advanced = ['comms', 'address','locality','postal_code','advanced_gender', 'partner','howlong','politic','religion','likes','dislikes','interest','channels','music','book','film','tv','romance','employment','education'];
        }
        $x = [];
        if ($basic) {
            foreach ($basic as $f => $v) {
                $x[$f] = $v;
            }
        }

        if ($profile_fields_advanced) {
            foreach ($profile_fields_advanced as $f) {
                $x[$f] = 1;
            }
        }

        return $x;
    }

    /**
     * @brief Clear notifyflags for a channel.
     *
     * Most likely during bulk import of content or other activity that is likely
     * to generate huge amounts of undesired notifications.
     *
     * @param int $channel_id
     *    The channel to disable notifications for
     * @return int
     *    Current notification flag value. Send this to notifications_on() to restore the channel settings when finished
     *    with the activity requiring notifications_off();
     */
    public static function notifications_off($channel_id)
    {
        $r = q(
            "select channel_notifyflags from channel where channel_id = %d limit 1",
            intval($channel_id)
        );
        q(
            "update channel set channel_notifyflags = 0 where channel_id = %d",
            intval($channel_id)
        );

        return intval($r[0]['channel_notifyflags']);
    }


    public static function notifications_on($channel_id, $value)
    {
        $x = q(
            "update channel set channel_notifyflags = %d where channel_id = %d",
            intval($value),
            intval($channel_id)
        );

        return $x;
    }


    public static function get_default_perms($uid)
    {

        $ret = [];

        $r = q(
            "select abook_xchan from abook where abook_channel = %d and abook_self = 1 limit 1",
            intval($uid)
        );
        if ($r) {
            $ret = Permissions::FilledPerms(get_abconfig($uid, $r[0]['abook_xchan'], 'system', 'my_perms', EMPTY_STR));
        }

        return $ret;
    }


    public static function profiles_build_sync($channel_id, $send = true)
    {
        $r = q(
            "select * from profile where uid = %d",
            intval($channel_id)
        );
        if ($r) {
            if ($send) {
                Libsync::build_sync_packet($channel_id, ['profile' => $r]);
            } else {
                return $r;
            }
        }
    }


    public static function auto_create($account_id)
    {

        if (! $account_id) {
            return false;
        }

        $arr = [];
        $arr['account_id'] = $account_id;
        $arr['name'] = get_aconfig($account_id, 'register', 'channel_name');
        $arr['nickname'] = legal_webbie(get_aconfig($account_id, 'register', 'channel_address'));
        $arr['permissions_role'] = get_aconfig($account_id, 'register', 'permissions_role');

        del_aconfig($account_id, 'register', 'channel_name');
        del_aconfig($account_id, 'register', 'channel_address');
        del_aconfig($account_id, 'register', 'permissions_role');

        if ((! $arr['name']) || (! $arr['nickname'])) {
            $x = q(
                "select * from account where account_id = %d limit 1",
                intval($account_id)
            );
            if ($x) {
                if (! $arr['name']) {
                    $arr['name'] = substr($x[0]['account_email'], 0, strpos($x[0]['account_email'], '@'));
                }
                if (! $arr['nickname']) {
                    $arr['nickname'] = legal_webbie(substr($x[0]['account_email'], 0, strpos($x[0]['account_email'], '@')));
                }
            }
        }
        if (! $arr['permissions_role']) {
            $arr['permissions_role'] = 'social';
        }

        if (self::validate_channelname($arr['name'])) {
            return false;
        }
        if ($arr['nickname'] === 'sys') {
            $arr['nickname'] = $arr['nickname'] . mt_rand(1000, 9999);
        }

        $arr['nickname'] = check_webbie([$arr['nickname'], $arr['nickname'] . mt_rand(1000, 9999)]);

        return self::create($arr);
    }

    public static function get_cover_photo($channel_id, $format = 'bbcode', $res = PHOTO_RES_COVER_1200)
    {

        $r = q(
            "select height, width, resource_id, edited, mimetype from photo where uid = %d and imgscale = %d and photo_usage = %d",
            intval($channel_id),
            intval($res),
            intval(PHOTO_COVER)
        );
        if (! $r) {
            return false;
        }

        $output = false;

        $url = z_root() . '/photo/' . $r[0]['resource_id'] . '-' . $res ;

        switch ($format) {
            case 'bbcode':
                $output = '[zrl=' . $r[0]['width'] . 'x' . $r[0]['height'] . ']' . $url . '[/zrl]';
                break;
            case 'html':
                $output = '<img class="zrl" width="' . $r[0]['width'] . '" height="' . $r[0]['height'] . '" src="' . $url . '" alt="' . t('cover photo') . '" />';
                break;
            case 'array':
            default:
                $output = [
                    'width' => $r[0]['width'],
                    'height' => $r[0]['height'],
                    'type' => $r[0]['mimetype'],
                    'updated' => $r[0]['edited'],
                    'url' => $url
                ];
                break;
        }

        return $output;
    }


    /**
     * @brief Return parsed HTML zcard template.
     *
     * @param array $channel
     * @param string $observer_hash (optional)
     * @param array $args (optional)
     * @return string parsed HTML from \e zcard template
     */
    public static function get_zcard($channel, $observer_hash = '', $args = [])
    {

        logger('get_zcard');

        $maxwidth = (($args['width']) ? intval($args['width']) : 0);
        $maxheight = (($args['height']) ? intval($args['height']) : 0);

        if (($maxwidth > 1200) || ($maxwidth < 1)) {
            $maxwidth = 1200;
            $cover_width = 1200;
        }

        if ($maxwidth <= 425) {
            $width = 425;
            $cover_width = 425;
            $size = 'hz_small';
            $cover_size = PHOTO_RES_COVER_425;
            $pphoto = ['mimetype' => $channel['xchan_photo_mimetype'], 'width' => 80 , 'height' => 80, 'href' => $channel['xchan_photo_m'] . '?rev=' . strtotime($channel['xchan_photo_date'])];
        } elseif ($maxwidth <= 900) {
            $width = 900;
            $cover_width = 850;
            $size = 'hz_medium';
            $cover_size = PHOTO_RES_COVER_850;
            $pphoto = ['mimetype' => $channel['xchan_photo_mimetype'], 'width' => 160 , 'height' => 160, 'href' => $channel['xchan_photo_l'] . '?rev=' . strtotime($channel['xchan_photo_date'])];
        } elseif ($maxwidth <= 1200) {
            $width = 1200;
            $cover_width = 1200;
            $size = 'hz_large';
            $cover_size = PHOTO_RES_COVER_1200;
            $pphoto = ['mimetype' => $channel['xchan_photo_mimetype'], 'width' => 300 , 'height' => 300, 'href' => $channel['xchan_photo_l'] . '?rev=' . strtotime($channel['xchan_photo_date'])];
        }

        //  $scale = (float) $maxwidth / $width;
        //  $translate = intval(($scale / 1.0) * 100);
        $scale = 0;
        $translate = 0;

        $channel['channel_addr'] = self::get_webfinger($channel);
        $zcard = ['chan' => $channel];

        $r = q(
            "select height, width, resource_id, imgscale, mimetype from photo where uid = %d and imgscale = %d and photo_usage = %d",
            intval($channel['channel_id']),
            intval($cover_size),
            intval(PHOTO_COVER)
        );

        if ($r) {
            $cover = $r[0];
            $cover['href'] = z_root() . '/photo/' . $r[0]['resource_id'] . '-' . $r[0]['imgscale'];
        } else {
            $cover = [ 'href' => z_root() . '/' . self::get_default_cover_photo($cover_width) ];
        }

        $o = replace_macros(Theme::get_template('zcard.tpl'), [
            '$maxwidth' => $maxwidth,
            '$scale' => $scale,
            '$translate' => $translate,
            '$size' => $size,
            '$cover' => $cover,
            '$pphoto' => $pphoto,
            '$zcard' => $zcard
        ]);

        return $o;
    }


    /**
     * @brief Return parsed HTML embed zcard template.
     *
     * @param array $channel
     * @param string $observer_hash (optional)
     * @param array $args (optional)
     * @return string parsed HTML from \e zcard_embed template
     */
    public static function get_zcard_embed($channel, $observer_hash = '', $args = [])
    {

        logger('get_zcard_embed');

        $maxwidth = (($args['width']) ? intval($args['width']) : 0);
        $maxheight = (($args['height']) ? intval($args['height']) : 0);

        if (($maxwidth > 1200) || ($maxwidth < 1)) {
            $maxwidth = 1200;
            $cover_width = 1200;
        }

        if ($maxwidth <= 425) {
            $width = 425;
            $cover_width = 425;
            $size = 'hz_small';
            $cover_size = PHOTO_RES_COVER_425;
            $pphoto = ['mimetype' => $channel['xchan_photo_mimetype'],  'width' => 80 , 'height' => 80, 'href' => $channel['xchan_photo_m']];
        } elseif ($maxwidth <= 900) {
            $width = 900;
            $cover_width = 850;
            $size = 'hz_medium';
            $cover_size = PHOTO_RES_COVER_850;
            $pphoto = ['mimetype' => $channel['xchan_photo_mimetype'],  'width' => 160 , 'height' => 160, 'href' => $channel['xchan_photo_l']];
        } elseif ($maxwidth <= 1200) {
            $width = 1200;
            $cover_width = 1200;
            $size = 'hz_large';
            $cover_size = PHOTO_RES_COVER_1200;
            $pphoto = ['mimetype' => $channel['xchan_photo_mimetype'],  'width' => 300 , 'height' => 300, 'href' => $channel['xchan_photo_l']];
        }

        $channel['channel_addr'] = self::get_webfinger($channel);
        $zcard = ['chan' => $channel];

        $r = q(
            "select height, width, resource_id, imgscale, mimetype from photo where uid = %d and imgscale = %d and photo_usage = %d",
            intval($channel['channel_id']),
            intval($cover_size),
            intval(PHOTO_COVER)
        );

        if ($r) {
            $cover = $r[0];
            $cover['href'] = z_root() . '/photo/' . $r[0]['resource_id'] . '-' . $r[0]['imgscale'];
        } else {
            $cover = [ 'href' => z_root() . '/' . self::get_default_cover_photo($cover_width) ];
        }

        $scale = 0;
        $translate = 0;

        return replace_macros(Theme::get_template('zcard_embed.tpl'), [
            '$maxwidth' => $maxwidth,
            '$scale' => $scale,
            '$translate' => $translate,
            '$size' => $size,
            '$cover' => $cover,
            '$pphoto' => $pphoto,
            '$zcard' => $zcard
        ]);
    }

    /**
     * @brief Get a channel array from a channel nickname.
     *
     * @param string $nick - A channel_address nickname
     * @return array|bool
     *   - array with channel entry
     *   - false if no channel with $nick was found
     */

    public static function from_username($nick, $include_removed = false)
    {

        $sql_extra = (($include_removed) ? "" : " and channel_removed = 0 ");

        // If we are provided a Unicode nickname convert to IDN

        $nick = punify($nick);

        // return a cached copy if there is a cached copy and it's a match.
        // Also check that there is an xchan_hash to validate the App::$channel data is complete
        // and that columns from both joined tables are present

        if (
            App::$channel && is_array(App::$channel) && array_key_exists('channel_address', App::$channel)
            && array_key_exists('xchan_hash', App::$channel) && App::$channel['channel_address'] === $nick
        ) {
            return App::$channel;
        }

        $r = q(
            "SELECT * FROM channel left join xchan on channel_hash = xchan_hash WHERE channel_address = '%s' $sql_extra LIMIT 1",
            dbesc($nick)
        );

        return(($r) ? array_shift($r) : false);
    }

    /**
     * @brief Get a channel array by a channel_hash.
     *
     * @param string $hash
     * @return array|bool false if channel ID not found, otherwise the channel array
     */

    public static function from_hash($hash, $include_removed = false)
    {

        $sql_extra = (($include_removed) ? "" : " and channel_removed = 0 ");

        if (
            App::$channel && is_array(App::$channel) && array_key_exists('channel_hash', App::$channel)
            && array_key_exists('xchan_hash', App::$channel) && App::$channel['channel_hash'] === $hash
        ) {
            return App::$channel;
        }

        $r = q(
            "SELECT * FROM channel left join xchan on channel_hash = xchan_hash WHERE channel_hash = '%s' $sql_extra LIMIT 1",
            dbesc($hash)
        );

        return(($r) ? array_shift($r) : false);
    }


    /**
     * @brief Get a channel array by a channel ID.
     *
     * @param int $id A channel ID
     * @return array|bool false if channel ID not found, otherwise the channel array
     */

    public static function from_id($id, $include_removed = false)
    {

        $sql_extra = (($include_removed) ? "" : " and channel_removed = 0 ");

        if (
            App::$channel && is_array(App::$channel) && array_key_exists('channel_id', App::$channel)
            && array_key_exists('xchan_hash', App::$channel) && intval(App::$channel['channel_id']) === intval($id)
        ) {
            return App::$channel;
        }

        $r = q(
            "SELECT * FROM channel LEFT JOIN xchan ON channel_hash = xchan_hash WHERE channel_id = %d $sql_extra LIMIT 1",
            dbesc($id)
        );

        return(($r) ? array_shift($r) : false);
    }

    /**
     * @brief
     *
     * @param array $channel
     * @return string
     */

    public static function get_webfinger($channel)
    {
        if (! ($channel && array_key_exists('channel_address', $channel))) {
            return '';
        }

        return strtolower($channel['channel_address'] . '@' . App::get_hostname());
    }


    /**
     * @brief Get manual channel conversation update config.
     *
     * Check the channel config \e manual_conversation_update, if not set fall back
     * to global system config, defaults to 1 if nothing set.
     *
     * @param int $channel_id
     * @return int
     */

    public static function manual_conv_update($channel_id)
    {

        $x = get_pconfig($channel_id, 'system', 'manual_conversation_update', get_config('system', 'manual_conversation_update', 1));
        return intval($x);
    }


    /**
     * @brief Return parsed HTML remote_login template.
     *
     * @return string with parsed HTML from \e remote_login template
     */
    public static function remote_login()
    {
        $o = replace_macros(Theme::get_template('remote_login.tpl'), [
            '$title' => t('Remote Authentication'),
            '$desc' => t('Enter your channel address (e.g. channel@example.com)'),
            '$submit' => t('Authenticate')
        ]);

        return $o;
    }

    public static function channel_store_lowlevel($arr)
    {
        $store = [
            'channel_account_id'      => ((array_key_exists('channel_account_id', $arr))      ? $arr['channel_account_id']      : '0'),
            'channel_primary'         => ((array_key_exists('channel_primary', $arr))         ? $arr['channel_primary']         : '0'),
            'channel_name'            => ((array_key_exists('channel_name', $arr))            ? $arr['channel_name']            : ''),
            'channel_parent'          => ((array_key_exists('channel_parent', $arr))          ? $arr['channel_parent']          : ''),
            'channel_address'         => ((array_key_exists('channel_address', $arr))         ? $arr['channel_address']         : ''),
            'channel_guid'            => ((array_key_exists('channel_guid', $arr))            ? $arr['channel_guid']            : ''),
            'channel_guid_sig'        => ((array_key_exists('channel_guid_sig', $arr))        ? $arr['channel_guid_sig']        : ''),
            'channel_hash'            => ((array_key_exists('channel_hash', $arr))            ? $arr['channel_hash']            : ''),
            'channel_timezone'        => ((array_key_exists('channel_timezone', $arr))        ? $arr['channel_timezone']        : 'UTC'),
            'channel_location'        => ((array_key_exists('channel_location', $arr))        ? $arr['channel_location']        : ''),
            'channel_theme'           => ((array_key_exists('channel_theme', $arr))           ? $arr['channel_theme']           : ''),
            'channel_startpage'       => ((array_key_exists('channel_startpage', $arr))       ? $arr['channel_startpage']       : ''),
            'channel_pubkey'          => ((array_key_exists('channel_pubkey', $arr))          ? $arr['channel_pubkey']          : ''),
            'channel_prvkey'          => ((array_key_exists('channel_prvkey', $arr))          ? $arr['channel_prvkey']          : ''),
            'channel_epubkey'         => ((array_key_exists('channel_epubkey', $arr))         ? $arr['channel_epubkey']         : ''),
            'channel_eprvkey'         => ((array_key_exists('channel_eprvkey', $arr))         ? $arr['channel_eprvkey']         : ''),
            'channel_notifyflags'     => ((array_key_exists('channel_notifyflags', $arr))     ? $arr['channel_notifyflags']     : '65535'),
            'channel_pageflags'       => ((array_key_exists('channel_pageflags', $arr))       ? $arr['channel_pageflags']       : '0'),
            'channel_dirdate'         => ((array_key_exists('channel_dirdate', $arr))         ? $arr['channel_dirdate']         : NULL_DATE),
            'channel_lastpost'        => ((array_key_exists('channel_lastpost', $arr))        ? $arr['channel_lastpost']        : NULL_DATE),
            'channel_deleted'         => ((array_key_exists('channel_deleted', $arr))         ? $arr['channel_deleted']         : NULL_DATE),
            'channel_active'          => ((array_key_exists('channel_active', $arr))          ? $arr['channel_active']          : NULL_DATE),
            'channel_max_anon_mail'   => ((array_key_exists('channel_max_anon_mail', $arr))   ? $arr['channel_max_anon_mail']   : '10'),
            'channel_max_friend_req'  => ((array_key_exists('channel_max_friend_req', $arr))  ? $arr['channel_max_friend_req']  : '10'),
            'channel_expire_days'     => ((array_key_exists('channel_expire_days', $arr))     ? $arr['channel_expire_days']     : '0'),
            'channel_passwd_reset'    => ((array_key_exists('channel_passwd_reset', $arr))    ? $arr['channel_passwd_reset']    : ''),
            'channel_default_group'   => ((array_key_exists('channel_default_group', $arr))   ? $arr['channel_default_group']   : ''),
            'channel_allow_cid'       => ((array_key_exists('channel_allow_cid', $arr))       ? $arr['channel_allow_cid']       : ''),
            'channel_allow_gid'       => ((array_key_exists('channel_allow_gid', $arr))       ? $arr['channel_allow_gid']       : ''),
            'channel_deny_cid'        => ((array_key_exists('channel_deny_cid', $arr))        ? $arr['channel_deny_cid']        : ''),
            'channel_deny_gid'        => ((array_key_exists('channel_deny_gid', $arr))        ? $arr['channel_deny_gid']        : ''),
            'channel_removed'         => ((array_key_exists('channel_removed', $arr))         ? $arr['channel_removed']         : '0'),
            'channel_system'          => ((array_key_exists('channel_system', $arr))          ? $arr['channel_system']          : '0'),
            'channel_moved'           => ((array_key_exists('channel_moved', $arr))           ? $arr['channel_moved']           : ''),
            'channel_password'        => ((array_key_exists('channel_password', $arr))        ? $arr['channel_password']        : ''),
            'channel_salt'            => ((array_key_exists('channel_salt', $arr))            ? $arr['channel_salt']            : '')
        ];

        return create_table_from_array('channel', $store);
    }

    public static function profile_store_lowlevel($arr)
    {

        $store = [
            'profile_guid'  => ((array_key_exists('profile_guid', $arr))  ? $arr['profile_guid']  : ''),
            'aid'           => ((array_key_exists('aid', $arr))           ? $arr['aid']           : 0),
            'uid'           => ((array_key_exists('uid', $arr))           ? $arr['uid']           : 0),
            'profile_name'  => ((array_key_exists('profile_name', $arr))  ? $arr['profile_name']  : ''),
            'is_default'    => ((array_key_exists('is_default', $arr))    ? $arr['is_default']    : 0),
            'hide_friends'  => 0,
            'fullname'      => ((array_key_exists('fullname', $arr))      ? $arr['fullname']      : ''),
            'pdesc'         => ((array_key_exists('pdesc', $arr))         ? $arr['pdesc']         : ''),
            'chandesc'      => ((array_key_exists('chandesc', $arr))      ? $arr['chandesc']      : ''),
            'dob'           => ((array_key_exists('dob', $arr))           ? $arr['dob']           : ''),
            'dob_tz'        => ((array_key_exists('dob_tz', $arr))        ? $arr['dob_tz']        : ''),
            'address'       => ((array_key_exists('address', $arr))       ? $arr['address']       : ''),
            'locality'      => ((array_key_exists('locality', $arr))      ? $arr['locality']      : ''),
            'region'        => ((array_key_exists('region', $arr))        ? $arr['region']        : ''),
            'postal_code'   => ((array_key_exists('postal_code', $arr))   ? $arr['postal_code']   : ''),
            'country_name'  => ((array_key_exists('country_name', $arr))  ? $arr['country_name']  : ''),
            'hometown'      => ((array_key_exists('hometown', $arr))      ? $arr['hometown']      : ''),
            'gender'        => ((array_key_exists('gender', $arr))        ? $arr['gender']        : ''),
            'marital'       => ((array_key_exists('marital', $arr))       ? $arr['marital']       : ''),
            'partner'       => ((array_key_exists('partner', $arr))       ? $arr['partner']       : ''),
            'howlong'       => ((array_key_exists('howlong', $arr))       ? $arr['howlong']       : NULL_DATE),
            'sexual'        => ((array_key_exists('sexual', $arr))        ? $arr['sexual']        : ''),
            'pronouns'      => ((array_key_exists('pronouns', $arr))      ? $arr['pronouns']      : ''),
            'politic'       => ((array_key_exists('politic', $arr))       ? $arr['politic']       : ''),
            'religion'      => ((array_key_exists('religion', $arr))      ? $arr['religion']      : ''),
            'keywords'      => ((array_key_exists('keywords', $arr))      ? $arr['keywords']      : ''),
            'likes'         => ((array_key_exists('likes', $arr))         ? $arr['likes']         : ''),
            'dislikes'      => ((array_key_exists('dislikes', $arr))      ? $arr['dislikes']      : ''),
            'about'         => ((array_key_exists('about', $arr))         ? $arr['about']         : ''),
            'summary'       => ((array_key_exists('summary', $arr))       ? $arr['summary']       : ''),
            'music'         => ((array_key_exists('music', $arr))         ? $arr['music']         : ''),
            'book'          => ((array_key_exists('book', $arr))          ? $arr['book']          : ''),
            'tv'            => ((array_key_exists('tv', $arr))            ? $arr['tv']            : ''),
            'film'          => ((array_key_exists('film', $arr))          ? $arr['film']          : ''),
            'interest'      => ((array_key_exists('interest', $arr))      ? $arr['interest']      : ''),
            'romance'       => ((array_key_exists('romance', $arr))       ? $arr['romance']       : ''),
            'employment'    => ((array_key_exists('employment', $arr))    ? $arr['employment']    : ''),
            'education'     => ((array_key_exists('education', $arr))     ? $arr['education']     : ''),
            'contact'       => ((array_key_exists('contact', $arr))       ? $arr['contact']       : ''),
            'channels'      => ((array_key_exists('channels', $arr))      ? $arr['channels']      : ''),
            'homepage'      => ((array_key_exists('homepage', $arr))      ? $arr['homepage']      : ''),
            'photo'         => ((array_key_exists('photo', $arr))         ? $arr['photo']         : ''),
            'thumb'         => ((array_key_exists('thumb', $arr))         ? $arr['thumb']         : ''),
            'publish'       => ((array_key_exists('publish', $arr))       ? $arr['publish']       : 0),
            'profile_vcard' => ((array_key_exists('profile_vcard', $arr)) ? $arr['profile_vcard'] : '')
        ];

        return create_table_from_array('profile', $store);
    }


    /**
     * @brief Removes a channel.
     *
     * @param int $channel_id
     * @param bool $local default true
     * @param bool $unset_session default false
     */

    public static function channel_remove($channel_id, $local = true, $unset_session = false)
    {

        if (! $channel_id) {
            return;
        }

        // global removal (all clones) not currently supported
        // hence this operation _may_ leave orphan data on remote servers

        $local = true;

        logger('Removing channel: ' . $channel_id);
        logger('local only: ' . intval($local));


        $r = q("select * from channel where channel_id = %d limit 1", intval($channel_id));
        if (! $r) {
            logger('channel not found: ' . $channel_id);
            return;
        }

        $channel = $r[0];

        /**
         * @hooks channel_remove
         *   Called when removing a channel.
         *   * \e array with entry from channel tabel for $channel_id
         */

        Hook::call('channel_remove', $channel);

        $r = q(
            "select iid from iconfig left join item on item.id = iconfig.iid
    		where item.uid = %d",
            intval($channel_id)
        );
        if ($r) {
            foreach ($r as $rr) {
                q(
                    "delete from iconfig where iid = %d",
                    intval($rr['iid'])
                );
            }
        }

        q("DELETE FROM app WHERE app_channel = %d", intval($channel_id));
        q("DELETE FROM atoken WHERE atoken_uid = %d", intval($channel_id));
        q("DELETE FROM chatroom WHERE cr_uid = %d", intval($channel_id));
        q("DELETE FROM conv WHERE uid = %d", intval($channel_id));

        q("DELETE FROM pgrp WHERE uid = %d", intval($channel_id));
        q("DELETE FROM pgrp_member WHERE uid = %d", intval($channel_id));
        q("DELETE FROM event WHERE uid = %d", intval($channel_id));
        q("DELETE FROM menu WHERE menu_channel_id = %d", intval($channel_id));
        q("DELETE FROM menu_item WHERE mitem_channel_id = %d", intval($channel_id));

        q("DELETE FROM notify WHERE uid = %d", intval($channel_id));
        q("DELETE FROM obj WHERE obj_channel = %d", intval($channel_id));


        q("DELETE FROM photo WHERE uid = %d", intval($channel_id));
        q("DELETE FROM attach WHERE uid = %d", intval($channel_id));
        q("DELETE FROM profile WHERE uid = %d", intval($channel_id));
        q("DELETE FROM source WHERE src_channel_id = %d", intval($channel_id));

        $r = q("select hash FROM attach WHERE uid = %d", intval($channel_id));
        if ($r) {
            foreach ($r as $rv) {
                attach_delete($channel_id, $rv['hash']);
            }
        }


        q(
            "delete from abook where abook_xchan = '%s' and abook_self = 1 ",
            dbesc($channel['channel_hash'])
        );

        $r = q(
            "update channel set channel_deleted = '%s', channel_removed = 1 where channel_id = %d",
            dbesc(datetime_convert()),
            intval($channel_id)
        );

        // remove items

        Run::Summon([ 'Channel_purge', $channel_id ]);

        // if this was the default channel, set another one as default

        if (App::$account['account_default_channel'] == $channel_id) {
            $r = q(
                "select channel_id from channel where channel_account_id = %d and channel_removed = 0 limit 1",
                intval(App::$account['account_id']),
                intval(PAGE_REMOVED)
            );
            if ($r) {
                $rr = q(
                    "update account set account_default_channel = %d where account_id = %d",
                    intval($r[0]['channel_id']),
                    intval(App::$account['account_id'])
                );
                logger("Default channel deleted, changing default to channel_id " . $r[0]['channel_id']);
            } else {
                $rr = q(
                    "update account set account_default_channel = 0 where account_id = %d",
                    intval(App::$account['account_id'])
                );
            }
        }

        logger('deleting hublocs', LOGGER_DEBUG);

        $r = q(
            "update hubloc set hubloc_deleted = 1 where hubloc_hash = '%s' and hubloc_url = '%s' ",
            dbesc($channel['channel_hash']),
            dbesc(z_root())
        );

        // Do we have any valid hublocs remaining?

        $hublocs = 0;

        $r = q(
            "select hubloc_id from hubloc where hubloc_hash = '%s' and hubloc_deleted = 0",
            dbesc($channel['channel_hash'])
        );
        if ($r) {
            $hublocs = count($r);
        }

        if (! $hublocs) {
            $r = q(
                "update xchan set xchan_deleted = 1 where xchan_hash = '%s' ",
                dbesc($channel['channel_hash'])
            );
            // send a cleanup message to other servers
            Run::Summon([ 'Notifier', 'purge_all', $channel_id ]);
        }

        //remove from file system

        $f = 'store/' . $channel['channel_address'];
        // This shouldn't happen but make sure the address isn't empty because that could do bad things
        if (is_dir($f) && $channel['channel_address']) {
            @rrmdir($f);
        }

        Run::Summon([ 'Directory', $channel_id ]);

        if ($channel_id == local_channel() && $unset_session) {
            App::$session->nuke();
            goaway(z_root());
        }
    }

    // execute this at least a week after removing a channel

    public static function channel_remove_final($channel_id)
    {

        q("delete from abook where abook_channel = %d", intval($channel_id));
        q("delete from abconfig where chan = %d", intval($channel_id));
        q("delete from pconfig where uid = %d", intval($channel_id));
        q("delete from channel where channel_id = %d", intval($channel_id));
    }


    /**
     * @brief This checks if a channel is allowed to publish executable code.
     *
     * It is up to the caller to determine if the observer or local_channel
     * is in fact the resource owner whose channel_id is being checked.
     *
     * @param int $channel_id
     * @return bool
     */
    public static function codeallowed($channel_id)
    {
        if (! intval($channel_id)) {
            return false;
        }

        $x = self::from_id($channel_id);
        if (($x) && ($x['channel_pageflags'] & PAGE_ALLOWCODE)) {
            return true;
        }

        return false;
    }

    public static function anon_identity_init($reqvars)
    {

        $x = [
                'request_vars' => $reqvars,
                'xchan' => null,
                'success' => 'unset'
        ];
        /**
         * @hooks anon_identity_init
         *   * \e array \b request_vars
         *   * \e string \b xchan - return value
         *   * \e string|int \b success - Must be a number, so xchan return value gets used
         */
        Hook::call('anon_identity_init', $x);

        if ($x['success'] !== 'unset' && intval($x['success']) && $x['xchan']) {
            return $x['xchan'];
        }

        // allow a captcha handler to over-ride
        if ($x['success'] !== 'unset' && (intval($x['success']) === 0)) {
            return false;
        }


        $anon_name  = strip_tags(trim($reqvars['anonname']));
        $anon_email = strip_tags(trim($reqvars['anonmail']));
        $anon_url   = strip_tags(trim($reqvars['anonurl']));

        if (! ($anon_name && $anon_email)) {
            logger('anonymous commenter did not complete form');
            return false;
        }

        if (! validate_email($anon_email)) {
            logger('enonymous email not valid');
            return false;
        }

        if (! $anon_url) {
            $anon_url = z_root();
        }

        $hash = hash('md5', $anon_email);

        $x = q(
            "select * from xchan where xchan_guid = '%s' and xchan_hash = '%s' and xchan_network = 'anon' limit 1",
            dbesc($anon_email),
            dbesc($hash)
        );

        if (! $x) {
            xchan_store_lowlevel([
                'xchan_guid'    => $anon_email,
                'xchan_hash'    => $hash,
                'xchan_name'    => $anon_name,
                'xchan_url'     => $anon_url,
                'xchan_network' => 'anon',
                'xchan_updated' => datetime_convert(),
                'xchan_name_date' => datetime_convert()
            ]);


            $x = q(
                "select * from xchan where xchan_guid = '%s' and xchan_hash = '%s' and xchan_network = 'anon' limit 1",
                dbesc($anon_email),
                dbesc($hash)
            );

            $photo = z_root() . '/' . self::get_default_profile_photo(300);
            $photos = import_remote_xchan_photo($photo, $hash);
            if ($photos) {
                $r = q(
                    "update xchan set xchan_updated = '%s', xchan_photo_date = '%s', xchan_photo_l = '%s', xchan_photo_m = '%s', xchan_photo_s = '%s', xchan_photo_mimetype = '%s' where xchan_guid = '%s' and xchan_hash = '%s' and xchan_network = 'anon' ",
                    dbesc(datetime_convert()),
                    dbesc(datetime_convert()),
                    dbesc($photos[0]),
                    dbesc($photos[1]),
                    dbesc($photos[2]),
                    dbesc($photos[3]),
                    dbesc($anon_email),
                    dbesc($hash)
                );
            }
        }

        return $x[0];
    }

    public static function url($channel)
    {

        // data validation - if this is wrong, log the call stack so we can find the issue

        if (! is_array($channel)) {
            btlogger('not a channel array: ' . print_r($channel, true));
        }

        if ($channel['channel_address'] === App::get_hostname() || intval($channel['channel_system'])) {
            return z_root();
        }

        return (($channel) ? z_root() . '/channel/' . $channel['channel_address'] : z_root());
    }


    public static function keyId($channel)
    {

        // data validation - if this is wrong, log the call stack so we can find the issue

        if (! is_array($channel)) {
            btlogger('not a channel array: ' . print_r($channel, true));
        }

        if ($channel['channel_address'] === App::get_hostname() || intval($channel['channel_system'])) {
            return z_root() .  '?operation=getkey';
        }

        return (($channel) ? z_root() . '/channel/' . $channel['channel_address'] : z_root()) . '?operation=getkey';
    }

    public static function is_group($uid)
    {
        $role = get_pconfig($uid, 'system', 'permissions_role');
        $rolesettings = PermissionRoles::role_perms($role);
        return ((isset($rolesettings['channel_type']) && $rolesettings['channel_type'] === 'group') ? true : false);
    }
}