<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2014 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
namespace Think\Db\Driver;
use Think\Db;
defined('THINK_PATH') or exit();
/**
 * Firebird数据库驱动
 */
class Ibase extends Db{

    protected $selectSql  =     'SELECT %LIMIT% %DISTINCT% %FIELD% FROM %TABLE%%JOIN%%WHERE%%GROUP%%HAVING%%ORDER%';
    /**
     * 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('interbase') ) {
            E(L('_NOT_SUPPERT_').':Interbase or Firebird');
        }
        if(!empty($config)) {
            $this->config   =   $config;
            if(empty($this->config['params'])) {
                $this->config['params'] =   array();
            }
        }
    }

    /**
     * 连接数据库方法
     * @access public
     * @throws Think\Execption
     */
    public function connect($config='',$linkNum=0) {
        if ( !isset($this->linkID[$linkNum]) ) {
            if(empty($config))  $config =   $this->config;
            $pconnect   = !empty($config['params']['persist'])? $config['params']['persist']:$this->pconnect;
            $conn = $pconnect ? 'ibase_pconnect':'ibase_connect';
            // 处理不带端口号的socket连接情况
            $host = $config['hostname'].($config['hostport']?"/{$config['hostport']}":'');
            $this->linkID[$linkNum] = $conn($host.':'.$config['database'], $config['username'], $config['password'],$config['charset'],0,3);
            if ( !$this->linkID[$linkNum]) {
                E(ibase_errmsg());
            }
            // 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() {
        ibase_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) {
        $this->initConnect(false);
        if ( !$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');
        $this->queryID = ibase_query($this->_linkID, $str);
        $this->debug();
        if ( false === $this->queryID ) {
            $this->error();
            return false;
        } else {
            return $this->getAll();
        }
    }

    /**
     * 执行语句
     * @access public
     * @param string $str  sql指令
     * @return integer
     */
    public function execute($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');
        $result =   ibase_query($this->_linkID, $str) ;
        $this->debug();
        if ( false === $result) {
            $this->error();
            return false;
        } else {
            $this->numRows = ibase_affected_rows($this->_linkID);
            $this->lastInsID =0;
            return $this->numRows;
        }
    }

    public function startTrans() {
        $this->initConnect(true);
        if ( !$this->_linkID ) return false;
        //数据rollback 支持
        if ($this->transTimes == 0) {
            ibase_trans( IBASE_DEFAULT, $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) {
            $result =  ibase_commit($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) {
            $result =ibase_rollback($this->_linkID);
            $this->transTimes = 0;
            if(!$result){
                $this->error();
                return false;
            }
        }
        return true;
    }

    /**
     * BLOB字段解密函数 Firebird特有
     * @access public
     * @param $blob 待解密的BLOB
     * @return 二进制数据
     */
     public function BlobDecode($blob) {
        $maxblobsize = 262144;
        $blob_data = ibase_blob_info($this->_linkID, $blob );
        $blobid = ibase_blob_open($this->_linkID, $blob );
        if( $blob_data[0] > $maxblobsize ) {
            $realblob = ibase_blob_get($blobid, $maxblobsize);
            while($string = ibase_blob_get($blobid, 8192)){
                $realblob .= $string;
            }
        } else {
            $realblob = ibase_blob_get($blobid, $blob_data[0]);
        }
        ibase_blob_close( $blobid );
        return( $realblob );
    }

    /**
     * 获得所有的查询数据
     * @access private
     * @return array
     */
    private function getAll() {
        //返回数据集
        $result = array();
        while ( $row = ibase_fetch_assoc($this->queryID)) {
            $result[]   =   $row;
        }
        //剑雷 2007.12.30 自动解密BLOB字段
        //取BLOB字段清单
        $bloblist = array();
        $fieldCount = ibase_num_fields($this->queryID);
        for ($i = 0; $i < $fieldCount; $i++) {
         $col_info = ibase_field_info($this->queryID, $i);
         if ($col_info['type']=='BLOB') {
           $bloblist[]=trim($col_info['name']);
         }
        }
       //如果有BLOB字段,就进行解密处理
       if (!empty($bloblist)) {
         $i=0;
         foreach ($result as $row) {
           foreach($bloblist as $field) {
               if (!empty($row[$field])) $result[$i][$field]=$this->BlobDecode($row[$field]);
          }
          $i++;
        }
      }
     return $result;
    }

    /**
     * 取得数据表的字段信息
     * @access public
     */
    public function getFields($tableName) {
        $result   =  $this->query('SELECT RDB$FIELD_NAME AS FIELD, RDB$DEFAULT_VALUE AS DEFAULT1, RDB$NULL_FLAG AS NULL1 FROM RDB$RELATION_FIELDS WHERE RDB$RELATION_NAME=UPPER(\''.$tableName.'\') ORDER By RDB$FIELD_POSITION');
        $info   =   array();
        if($result) {
            foreach ($result as $key => $val) {
                $info[trim($val['FIELD'])] = array(
                    'name'    => trim($val['FIELD']),
                    'type'    => '',
                    'notnull' => (bool) ($val['NULL1'] ==1), // 1表示不为Null
                    'default' => $val['DEFAULT1'],
                    'primary' => false,
                    'autoinc' => false,
                );
           }
      }
      //剑雷 取表字段类型
     $sql='select first 1 * from '. $tableName;
     $rs_temp = ibase_query ($this->_linkID, $sql);
     $fieldCount = ibase_num_fields($rs_temp);

     for ($i = 0; $i < $fieldCount; $i++)
     {
       $col_info = ibase_field_info($rs_temp, $i);
       $info[trim($col_info['name'])]['type']=$col_info['type'];
     }
     ibase_free_result ($rs_temp);

     //剑雷 取表的主键
     $sql='select b.rdb$field_name as FIELD_NAME from rdb$relation_constraints a join rdb$index_segments b
on a.rdb$index_name=b.rdb$index_name
where a.rdb$constraint_type=\'PRIMARY KEY\' and a.rdb$relation_name=UPPER(\''.$tableName.'\')';
     $rs_temp = ibase_query ($this->_linkID, $sql);
     while ($row=ibase_fetch_object($rs_temp)) {
      $info[trim($row->FIELD_NAME)]['primary']=True;
     }
     ibase_free_result ($rs_temp);

     return $info;
    }

    /**
     * 取得数据库的表信息
     * @access public
     */
    public function getTables($dbName='') {
        $sql='SELECT DISTINCT RDB$RELATION_NAME FROM RDB$RELATION_FIELDS WHERE RDB$SYSTEM_FLAG=0';
        $result   =  $this->query($sql);
        $info   =   array();
        foreach ($result as $key => $val) {
            $info[$key] = trim(current($val));
        }
        return $info;
    }

    /**
     * 关闭数据库
     * @access public
     */
    public function close() {
        if ($this->_linkID){
            ibase_close($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 = ibase_errcode().':'.ibase_errmsg();
        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 $str  SQL指令
     * @return string
     */
    public function escapeString($str) {
        return str_replace("'", "''", $str);
    }

    /**
     * limit
     * @access public
     * @param $limit limit表达式
     * @return string
     */
	public function parseLimit($limit) {
        $limitStr    = '';
        if(!empty($limit)) {
            $limit  =   explode(',',$limit);
            if(count($limit)>1) {
                 $limitStr = ' FIRST '.($limit[1]-$limit[0]).' SKIP '.$limit[0].' ';
            }else{
              $limitStr = ' FIRST '.$limit[0].' ';
            }
        }
		return $limitStr;
	}
}