if ( !defined( 'WP_CACHE_KEY_SALT' ) )
define( 'WP_CACHE_KEY_SALT', '' );

if ( class_exists( 'Memcached' ) ) {

function wp_cache_add( $key, $data, $group = '', $expire = 0 ) {
global $wp_object_cache;
return $wp_object_cache->add( $key, $data, $group, $expire );
}

function wp_cache_incr( $key, $n = 1, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->incr( $key, $n, $group );
}

function wp_cache_decr( $key, $n = 1, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->decr( $key, $n, $group );
}

function wp_cache_close() {
global $wp_object_cache;
return $wp_object_cache->close();
}

function wp_cache_delete( $key, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->delete( $key, $group );
}

function wp_cache_delete_multi( $keys, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->delete_multi( $keys, $group );
}

function wp_cache_flush() {
global $wp_object_cache;
return $wp_object_cache->flush();
}

function wp_cache_get( $key, $group = '', $force = false, &$found = null ) {
global $wp_object_cache;
return $wp_object_cache->get( $key, $group, $force, $found );
}

function wp_cache_get_with_cas( $key, $group = '', &$cas_token = null ) {
global $wp_object_cache;
return $wp_object_cache->get_with_cas( $key, $group, $cas_token );
}

function wp_cache_cas( $cas_token, $key, $data, $group = '', $expire = 0 ) {
global $wp_object_cache;
return $wp_object_cache->cas( $cas_token, $key, $data, $group, $expire );
}

function wp_cache_get_multi( $keys, $group = '' ) {
global $wp_object_cache;
return $wp_object_cache->get_multi( $keys, $group );
}

function wp_cache_set_multi( $keys, $datas, $group= '', $expire = 0 ) {
global $wp_object_cache;
return $wp_object_cache->set_multi( $keys, $datas, $group, $expire);
}

function wp_cache_init() {
global $wp_object_cache;
$wp_object_cache = new WP_Object_Cache();
}

function wp_cache_replace( $key, $data, $group = '', $expire = 0 ) {
global $wp_object_cache;
return $wp_object_cache->replace( $key, $data, $group, $expire );
}

function wp_cache_set( $key, $data, $group = '', $expire = 0 ) {
global $wp_object_cache;

if ( defined( 'WP_INSTALLING' ) == false ) {
return $wp_object_cache->set( $key, $data, $group, $expire );
} else {
return $wp_object_cache->delete( $key, $group );
}
}

function wp_cache_switch_to_blog( $blog_id ) {
global $wp_object_cache;

return $wp_object_cache->switch_to_blog( $blog_id );
}

function wp_cache_add_global_groups( $groups ) {
global $wp_object_cache;
$wp_object_cache->add_global_groups( $groups );
}

function wp_cache_add_non_persistent_groups( $groups ) {
global $wp_object_cache;
$wp_object_cache->add_non_persistent_groups( $groups );
}

function wordpress_memcached_get_stats() {
global $wp_object_cache;
return $wp_object_cache->stats();
}

class WP_Object_Cache {
private $global_groups = array();
private $no_mc_groups = array();
private $cache = array();
private $mc = null;

function add( $id, $data, $group = 'default', $expire = 0 ) {
$key = $this->key( $id, $group );

if ( is_object( $data ) ) {
$data = clone $data;
}

if ( in_array( $group, $this->no_mc_groups ) ) {
$this->cache[ $key ] = $data;
return true;
} elseif ( isset( $this->cache[ $key ] ) && $this->cache[ $key ] !== false ) {
return false;
}

$result = $this->mc->add( $key, $data, $expire );

if ( false !== $result ) {
$this->cache[ $key ] = $data;
}

return $result;
}

function add_global_groups( $groups ) {
if ( ! is_array( $groups ) ) {
$groups = (array) $groups;
}

$this->global_groups = array_merge( $this->global_groups, $groups );
$this->global_groups = array_unique( $this->global_groups );
}

function add_non_persistent_groups( $groups ) {
if ( ! is_array( $groups ) ) {
$groups = (array) $groups;
}

$this->no_mc_groups = array_merge( $this->no_mc_groups, $groups );
$this->no_mc_groups = array_unique( $this->no_mc_groups );
}

function incr( $id, $n = 1, $group = 'default' ) {
$key = $this->key( $id, $group );

return $this->mc->increment( $key, $n );
}

function decr( $id, $n = 1, $group = 'default' ) {
$key = $this->key( $id, $group );

return $this->mc->decrement( $key, $n );
}

function close() {
$this->mc->quit();
}

function delete( $id, $group = 'default' ) {

$key = $this->key( $id, $group );

unset( $this->cache[ $key ] );

if ( in_array( $group, $this->no_mc_groups ) ) {
return true;
}

return $this->mc->delete( $key );
}

function delete_multi($ids, $group = 'default'){
$keys = array_map(function($id) use ($group){ return $this->key( $id, $group ); }, $ids);

if ( in_array( $group, $this->no_mc_groups ) ) {
return true;
}

foreach ($keys as $key) {
unset( $this->cache[ $key ] );
}

$result = $this->mc->deleteMulti( $keys );

return $result;
}

function flush() {
return $this->mc->flush();
}

function get( $id, $group = 'default', $force = false, &$found = null ) {
$key = $this->key( $id, $group );

if ( isset( $this->cache[ $key ] ) && ( ! $force || in_array( $group, $this->no_mc_groups ) ) ) {
if ( is_object( $this->cache[ $key ] ) ) {
$value = clone $this->cache[ $key ];
} else {
$value = $this->cache[ $key ];
}
$found = true;
} else if ( in_array( $group, $this->no_mc_groups ) ) {
$value = false;
$found = true;
} else {
$value = $this->mc->get( $key );
$found = true;
if ($this->mc->getResultCode() == Memcached::RES_NOTFOUND) {
$value = false;
$found = false;
}

$this->cache[ $key ] = $value;
}

return $value;
}

function get_with_cas( $id, $group = 'default', &$cas_token=null){
$key = $this->key( $id, $group );

if(defined('Memcached::GET_EXTENDED')) {
$result = $this->mc->get($key, null, Memcached::GET_EXTENDED);

if ($this->mc->getResultCode() == Memcached::RES_NOTFOUND) {
$value = false;
}else{
$value = $result['value'];
$cas_token = $result['cas'];
}
}else{
$value = $this->mc->get($key, null, $cas_token);

if ($this->mc->getResultCode() == Memcached::RES_NOTFOUND) {
$value = false;
}
}

return $value;
}

function cas( $cas_token, $id, $data, $group = 'default', $expire = 0 ) {
$key = $this->key( $id, $group );

if ( is_object( $data ) ) {
$data = clone $data;
}

$this->cache[ $key ] = $data;

return $this->mc->cas( $cas_token, $key, $data, $expire );
}

function get_multi( $ids, $group = 'default' ) {
if ( in_array( $group, $this->no_mc_groups )){
return false;
}

$keys = array_map(function($id) use ($group){
return $this->key( $id, $group );
}, $ids);

$key_ids = array_combine($keys, $ids);

// $version = intval($this->mc->getVersion());
// if ($version < 3) {
// $results = $this->mc->getMulti( $keys, $cas_tokens, Memcached::GET_PRESERVE_ORDER );
// } else {
// $results = $this->mc->getMulti( $keys, Memcached::GET_PRESERVE_ORDER);
// }

$results = $this->mc->getMulti($keys);

if($results){
$returns = array();
foreach ($key_ids as $key=>$id) {
if(isset($results[$key])){
$this->cache[ $key ] = $results[$key];
$returns[$id] = $results[$key];
}
}

return $returns;
}

return $results;
}

function key( $id, $group ) {
if ( empty( $group ) ) {
$group = 'default';
}

if ( false !== array_search( $group, $this->global_groups ) ) {
$prefix = $this->global_prefix;
} else {
$prefix = $this->blog_prefix;
}

return preg_replace( '/\s+/', '', WP_CACHE_KEY_SALT . "$prefix$group:$id" );
}

function replace( $id, $data, $group = 'default', $expire = 0 ) {
$key = $this->key( $id, $group );

if ( is_object( $data ) ) {
$data = clone $data;
}

$result = $this->mc->replace( $key, $data, $expire );

if ( false !== $result ) {
$this->cache[ $key ] = $data;
}

return $result;
}

function set( $id, $data, $group = 'default', $expire = 0 ) {
$key = $this->key( $id, $group );

if ( is_object( $data ) ) {
$data = clone $data;
}

$this->cache[ $key ] = $data;

if ( in_array( $group, $this->no_mc_groups ) ) {
return true;
}

return $this->mc->set( $key, $data, $expire );
}

function set_multi( $ids, $datas, $group = 'default', $expire = 0 ) {

if ( in_array( $group, $this->no_mc_groups ) ) {
return true;
}

$keys = array_map(function($id) use ($group){
return $this->key( $id, $group );
}, $ids);

foreach ($keys as $i=>$key) {
$this->cache[ $key ] = $datas[$i];
}

$items = array_combine($keys, $datas);

$result = $this->mc->setMulti( $items, $expire );

return $result;
}

function switch_to_blog( $blog_id ) {
global $table_prefix;
$blog_id = (int) $blog_id;
$this->blog_prefix = ( is_multisite() ? $blog_id : $table_prefix ) . ':';
}

function colorize_debug_line( $line ) {
$colors = array(
'get' => 'green',
'set' => 'purple',
'add' => 'blue',
'delete' => 'red'
);

$cmd = substr( $line, 0, strpos( $line, ' ' ) );

$cmd2 = "<span style='color:{$colors[$cmd]}'>$cmd</span>";

return $cmd2 . substr( $line, strlen( $cmd ) ) . "\n";
}

function stats() {
$stats_text = '';

$stats = $this->mc->getStats();
foreach ( $stats as $key => $details ) {
$stats_text .= 'memcached: ' . $key . "\n\r";
foreach ( $details as $name => $value ) {
$stats_text .= $name . ': ' . $value . "\n\r";
}
$stats_text .= "\n\r";
}

return $stats_text;
}

function get_mc(){
return $this->mc;
}

function failure_callback( $host, $port ) {
}

function __construct() {

$this->mc = new Memcached();
$this->mc ->setOption(Memcached::OPT_LIBKETAMA_COMPATIBLE, true);

if(!$this->mc->getServerList()){
$this->mc->addServer('127.0.0.1', 11211, 100);
}

// global $memcached_servers;

// if ( isset( $memcached_servers ) ) {
// $buckets = $memcached_servers;
// } else {
// $buckets = array( '127.0.0.1' );
// }

// reset( $buckets );
// if ( is_int( key( $buckets ) ) ) {
// $buckets = array( 'default' => $buckets );
// }

// foreach ( $buckets as $bucket => $servers ) {
// $this->mc[ $bucket ] = new Memcached($bucket);
// $this->mc[ $bucket ] ->setOption(Memcached::OPT_LIBKETAMA_COMPATIBLE, true);

// if(count($this->mc[ $bucket ]->getServerList())){
// continue;
// }

// $instances = array();
// foreach ( $servers as $server ) {
// @list( $node, $port ) = explode( ':', $server.":" );
// if ( empty( $port ) ) {
// $port = ini_get( 'memcache.default_port' );
// }
// $port = intval( $port );
// if ( ! $port ) {
// $port = 11211;
// }

// $instances[] = array( $node, $port, 1 );
// }
// $this->mc[ $bucket ]->addServers( $instances );
// }

global $blog_id, $table_prefix;

$this->global_prefix = '';
$this->blog_prefix = '';

if ( function_exists( 'is_multisite' ) ) {
$this->global_prefix = ( is_multisite() || defined( 'CUSTOM_USER_TABLE' ) && defined( 'CUSTOM_USER_META_TABLE' ) ) ? '' : $table_prefix;
$this->blog_prefix = ( is_multisite() ? $blog_id : $table_prefix ) . ':';
}

// $this->cache_hits =& $this->stats['get'];
// $this->cache_misses =& $this->stats['add'];
}
}
} else {
// No Memcached
if ( function_exists( 'wp_using_ext_object_cache' ) ) {
// In 3.7+, we can handle this smoothly
wp_using_ext_object_cache( false );
} else {
// In earlier versions, there isn't a clean bail-out method.
wp_die( 'Memcached class not available.' );
}
}