<?php

// +----------------------------------------------------------------------

// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]

// +----------------------------------------------------------------------

// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.

// +----------------------------------------------------------------------

// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )

// +----------------------------------------------------------------------

// | Author: liu21st <liu21st@gmail.com>

// +----------------------------------------------------------------------



defined('THINK_PATH') or exit();



/**

 * Mysql数据库驱动类

 * @category   Think

 * @package  Think

 * @subpackage  Driver.Db

 * @author    liu21st <liu21st@gmail.com>

 */

class DbMysql extends Db{



    /**

     * 架构函数 读取数据库配置信息

     * @access public

     * @param array $config 数据库配置数组

     */

    public function __construct($config=''){

        if ( !extension_loaded('mysql') ) {

            throw_exception(L('_NOT_SUPPERT_').':mysql');

        }

        if(!empty($config)) {

            $this->config   =   $config;

            if(empty($this->config['params'])) {

                $this->config['params'] =   '';

            }

        }

    }



    /**

     * 连接数据库方法

     * @access public

     * @throws ThinkExecption

     */

    public function connect($config='',$linkNum=0,$force=false) {

        if ( !isset($this->linkID[$linkNum]) ) {

            if(empty($config))  $config =   $this->config;

            // 处理不带端口号的socket连接情况

            $host = $config['hostname'].($config['hostport']?":{$config['hostport']}":'');

            // 是否长连接

            $pconnect   = !empty($config['params']['persist'])? $config['params']['persist']:$this->pconnect;

            if($pconnect) {

                $this->linkID[$linkNum] = mysql_pconnect( $host, $config['username'], $config['password'],131072);

            }else{

                $this->linkID[$linkNum] = mysql_connect( $host, $config['username'], $config['password'],true,131072);

            }

            if ( !$this->linkID[$linkNum] || (!empty($config['database']) && !mysql_select_db($config['database'], $this->linkID[$linkNum])) ) {

                throw_exception(mysql_error());

            }

            $dbVersion = mysql_get_server_info($this->linkID[$linkNum]);

            //使用UTF8存取数据库

            mysql_query("SET NAMES '".C('DB_CHARSET')."'", $this->linkID[$linkNum]);

            //设置 sql_model

            if($dbVersion >'5.0.1'){

                mysql_query("SET sql_mode=''",$this->linkID[$linkNum]);

            }

            // 标记连接成功

            $this->connected    =   true;

            // 注销数据库连接配置信息

            if(1 != C('DB_DEPLOY_TYPE')) unset($this->config);

        }

        return $this->linkID[$linkNum];

    }



    /**

     * 释放查询结果

     * @access public

     */

    public function free() {

        mysql_free_result($this->queryID);

        $this->queryID = null;

    }



    /**

     * 执行查询 返回数据集

     * @access public

     * @param string $str  sql指令

     * @return mixed

     */

    public function query($str) {

        if(0===stripos($str, 'call')){ // 存储过程查询支持

            $this->close();

            $this->connected    =   false;

        }

        $this->initConnect(false);

        if ( !$this->_linkID ) return false;

        $this->queryStr = $str;

        //释放前次的查询结果

        if ( $this->queryID ) {    $this->free();    }

        N('db_query',1);

        // 记录开始执行时间

        G('queryStartTime');

        $this->queryID = mysql_query($str, $this->_linkID);

        $this->debug();

        if ( false === $this->queryID ) {

            $this->error();

            return false;

        } else {

            $this->numRows = mysql_num_rows($this->queryID);

            return $this->getAll();

        }

    }



    /**

     * 执行语句

     * @access public

     * @param string $str  sql指令

     * @return integer|false

     */

    public function execute($str) {

        $this->initConnect(true);

        if ( !$this->_linkID ) return false;

        $this->queryStr = $str;

        //释放前次的查询结果

        if ( $this->queryID ) {    $this->free();    }

        N('db_write',1);

        // 记录开始执行时间

        G('queryStartTime');

        $result =   mysql_query($str, $this->_linkID) ;

        $this->debug();

        if ( false === $result) {

            $this->error();

            return false;

        } else {

            $this->numRows = mysql_affected_rows($this->_linkID);

            $this->lastInsID = mysql_insert_id($this->_linkID);

            return $this->numRows;

        }

    }



    /**

     * 启动事务

     * @access public

     * @return void

     */

    public function startTrans() {

        $this->initConnect(true);

        if ( !$this->_linkID ) return false;

        //数据rollback 支持

        if ($this->transTimes == 0) {

            mysql_query('START TRANSACTION', $this->_linkID);

        }

        $this->transTimes++;

        return ;

    }



    /**

     * 用于非自动提交状态下面的查询提交

     * @access public

     * @return boolen

     */

    public function commit() {

        if ($this->transTimes > 0) {

            $result = mysql_query('COMMIT', $this->_linkID);

            $this->transTimes = 0;

            if(!$result){

                $this->error();

                return false;

            }

        }

        return true;

    }



    /**

     * 事务回滚

     * @access public

     * @return boolen

     */

    public function rollback() {

        if ($this->transTimes > 0) {

            $result = mysql_query('ROLLBACK', $this->_linkID);

            $this->transTimes = 0;

            if(!$result){

                $this->error();

                return false;

            }

        }

        return true;

    }



    /**

     * 获得所有的查询数据

     * @access private

     * @return array

     */

    private function getAll() {

        //返回数据集

        $result = array();

        if($this->numRows >0) {

            while($row = mysql_fetch_assoc($this->queryID)){

                $result[]   =   $row;

            }

            mysql_data_seek($this->queryID,0);

        }

        return $result;

    }



    /**

     * 取得数据表的字段信息

     * @access public

     * @return array

     */

    public function getFields($tableName) {

        $result =   $this->query('SHOW COLUMNS FROM '.$this->parseKey($tableName));

        $info   =   array();

        if($result) {

            foreach ($result as $key => $val) {

                $info[$val['Field']] = array(

                    'name'    => $val['Field'],

                    'type'    => $val['Type'],

                    'notnull' => (bool) (strtoupper($val['Null']) === 'NO'), // not null is empty, null is yes

                    'default' => $val['Default'],

                    'primary' => (strtolower($val['Key']) == 'pri'),

                    'autoinc' => (strtolower($val['Extra']) == 'auto_increment'),

                );

            }

        }

        return $info;

    }



    /**

     * 取得数据库的表信息

     * @access public

     * @return array

     */

    public function getTables($dbName='') {

        if(!empty($dbName)) {

           $sql    = 'SHOW TABLES FROM '.$dbName;

        }else{

           $sql    = 'SHOW TABLES ';

        }

        $result =   $this->query($sql);

        $info   =   array();

        foreach ($result as $key => $val) {

            $info[$key] = current($val);

        }

        return $info;

    }



    /**

     * 替换记录

     * @access public

     * @param mixed $data 数据

     * @param array $options 参数表达式

     * @return false | integer

     */

    public function replace($data,$options=array()) {

        foreach ($data as $key=>$val){

            $value   =  $this->parseValue($val);

            if(is_scalar($value)) { // 过滤非标量数据

                $values[]   =  $value;

                $fields[]     =  $this->parseKey($key);

            }

        }

        $sql   =  'REPLACE INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES ('.implode(',', $values).')';

        return $this->execute($sql);

    }



    /**

     * 插入记录

     * @access public

     * @param mixed $datas 数据

     * @param array $options 参数表达式

     * @param boolean $replace 是否replace

     * @return false | integer

     */

    public function insertAll($datas,$options=array(),$replace=false) {

        if(!is_array($datas[0])) return false;

        $fields = array_keys($datas[0]);

        array_walk($fields, array($this, 'parseKey'));

        $values  =  array();

        foreach ($datas as $data){

            $value   =  array();

            foreach ($data as $key=>$val){

                $val   =  $this->parseValue($val);

                if(is_scalar($val)) { // 过滤非标量数据

                    $value[]   =  $val;

                }

            }

            $values[]    = '('.implode(',', $value).')';

        }

        $sql   =  ($replace?'REPLACE':'INSERT').' INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES '.implode(',',$values);

        return $this->execute($sql);

    }



    /**

     * 关闭数据库

     * @access public

     * @return void

     */

    public function close() {

        if ($this->_linkID){

            mysql_close($this->_linkID);

        }

        $this->_linkID = null;

    }



    /**

     * 数据库错误信息

     * 并显示当前的SQL语句

     * @access public

     * @return string

     */

    public function error() {

        $this->error = mysql_errno().':'.mysql_error($this->_linkID);

        if('' != $this->queryStr){

            $this->error .= "\n [ SQL语句 ] : ".$this->queryStr;

        }

        trace($this->error,'','ERR');

        return $this->error;

    }



    /**

     * SQL指令安全过滤

     * @access public

     * @param string $str  SQL字符串

     * @return string

     */

    public function escapeString($str) {

        if($this->_linkID) {

            return mysql_real_escape_string($str,$this->_linkID);

        }else{

            return mysql_escape_string($str);

        }

    }



    /**

     * 字段和表名处理添加`

     * @access protected

     * @param string $key

     * @return string

     */

    protected function parseKey(&$key) {

        $key   =  trim($key);

        if(!preg_match('/[,\'\"\*\(\)`.\s]/',$key)) {

           $key = '`'.$key.'`';

        }

        return $key;

    }

}