<?php
/*
 * Laconica - a distributed open-source microblogging tool
 * Copyright (C) 2008, Controlez-Vous, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

if (!defined('LACONICA')) { exit(1); }

require_once INSTALLDIR.'/classes/Memcached_DataObject.php';

class Memcached_DataObject extends DB_DataObject 
{
    function &staticGet($cls, $k, $v=NULL) {
		if (is_null($v)) {
			$v = $k;
			# XXX: HACK!
			$i = new $cls;
			$keys = $i->keys();
			$k = $keys[0];
			unset($i);
		}
		$i = Memcached_DataObject::getcached($cls, $k, $v);
		if ($i) {
			return $i;
		} else {
			$i = DB_DataObject::staticGet($cls, $k, $v);
			if ($i) {
				$i->encache();
			}
			return $i;
		}
	}

	function &pkeyGet($cls, $kv) {
		$i = Memcached_DataObject::multicache($cls, $kv);
		if ($i) {
			return $i;
		} else {
			$i = new $cls();
			foreach ($kv as $k => $v) {
				$i->$k = $v;
			}
			if ($i->find(true)) {
				$i->encache();
			} else {
				$i = NULL;
			}
            return $i;
		}
	}

	function insert() {
		$result = parent::insert();
		return $result;
	}
	
	function update($orig=NULL) {
		if (is_object($orig) && $orig instanceof Memcached_DataObject) {
			$orig->decache(); # might be different keys
		}
		$result = parent::update($orig);
		if ($result) {
			$this->encache();
		}
		return $result;
	}
	
	function delete() {
		$this->decache(); # while we still have the values!
		return parent::delete();
	}
	
	static function memcache() {
		return common_memcache();
	}
	
	static function cacheKey($cls, $k, $v) {
		return common_cache_key(strtolower($cls).':'.$k.':'.$v);
	}
	
	static function getcached($cls, $k, $v) {
		$c = Memcached_DataObject::memcache();
		if (!$c) {
			return false;
		} else {
			return $c->get(Memcached_DataObject::cacheKey($cls, $k, $v));
		}
	}

	function keyTypes() {
		global $_DB_DATAOBJECT;
        if (!isset($_DB_DATAOBJECT['INI'][$this->_database][$this->__table."__keys"])) {
			$this->databaseStructure();

        }
		return $_DB_DATAOBJECT['INI'][$this->_database][$this->__table."__keys"];
	}
	
	function encache() {
		$c = $this->memcache();
		if (!$c) {
			return false;
		} else {
			$pkey = array();
			$pval = array();			
			$types = $this->keyTypes();
			ksort($types);
			foreach ($types as $key => $type) {
				if ($type == 'K') {
					$pkey[] = $key;
					$pval[] = $this->$key;
				} else {
					$c->set($this->cacheKey($this->tableName(), $key, $this->$key), $this);
				}
			}
			# XXX: should work for both compound and scalar pkeys
			$pvals = implode(',', $pval);
			$pkeys = implode(',', $pkey);
			$c->set($this->cacheKey($this->tableName(), $pkeys, $pvals), $this);
		}
	}
	
	function decache() {
		$c = $this->memcache();
		if (!$c) {
			return false;
		} else {
			$pkey = array();
			$pval = array();			
			$types = $this->keyTypes();
			ksort($types);
			foreach ($types as $key => $type) {
				if ($type == 'K') {
					$pkey[] = $key;
					$pval[] = $this->$key;
				} else {
					$c->delete($this->cacheKey($this->tableName(), $key, $this->$key));
				}
			}
			# should work for both compound and scalar pkeys
			# XXX: comma works for now but may not be safe separator for future keys
			$pvals = implode(',', $pval);
			$pkeys = implode(',', $pkey);
			$c->delete($this->cacheKey($this->tableName(), $pkeys, $pvals));
		}
	}

	function multicache($cls, $kv) {
		ksort($kv);
		$c = Memcached_DataObject::memcache();
		if (!$c) {
			return false;
		} else {
			$pkeys = implode(',', array_keys($kv));
			$pvals = implode(',', array_values($kv));
			return $c->get(Memcached_DataObject::cacheKey($cls, $pkeys, $pvals));
		}
	}

    function getSearchEngine($table) {
        require_once INSTALLDIR.'/lib/search_engines.php';
        static $search_engine;
        if (!isset($search_engine)) {
                $connected = false;
                if (common_config('sphinx', 'enabled')) {
                    $search_engine = new SphinxSearch($this, $table);
                    $connected = $search_engine->is_connected();
                }

                // unable to connect to sphinx' search daemon
                if (!$connected) {
                    if ('mysql' === common_config('db', 'type')) {
                        $search_engine = new MySQLSearch($this, $table);
                    } else {
                        $search_engine = new PGSearch($this, $table);
                    }
                }
        }
        return $search_engine;
    }
}