/*

事务脚本模式: 类似于thinkphp中的model层，或者说就是操作数据库的类。

个人觉得实践中使用起来还是挺简单方便的，就是SQL语句写死了的话，灵活性就不够。

示例代码如下：

*/

namespace woo\process;

abstract class Base{

static $DB; //pdo对象

static $stmts = array(); //sql语句句柄

function __construct (){

$dsn = \woo\base\ApplicationRegistry::getDSN();

if(is_null($dsn)){

throw new \woo\base\AppException("No DSN");

}

self::$DB = new PDO($dsn);

self::$DB->setAttribute(\PDO::ATTR_ERRMODE,\PDO::ERRMODE_EXCEPTION);

}

function prepareStatement($stmt_s){ //缓存sql语句句柄

if(isset(self::$stmts($stmt_s)){

return self::$stmts[$stmt_s];

}

$stmt_handle = self::$DB->prepare($stmt_s);

self::$stmts[$stmt_s] = $stmt_handle;

return $stmt_handle;

}

protected function doStatement($stmt_s,$values_a){ //执行sql并获取一个语句资源

$sth = $this->prepareStatement($stmt_s);

$sth->closeCursor();

$db_result = $sth->execute($values_a);

return $sth;

}

}

//这个类就是向数据库中写入一些数据，比较简单没什么好多说的

class VenueManager extends Base{

static $add_venue = "INSERT INTO venue (name) values(?)";

static $add_space = "INSERT INTO space (name,venue) values(?,?)";

static $check_slot = "SELECT id,name FROM event WHERE space = ? AND (start+duration)>? AND start ";

static $add_event = "INSERT INTO event (name,space,start,duration) values(?,?,?,?)";

function addVenue($name,$space_array){

$ret = array();

$ret['venue'] = array($name);

$this->doStatement(self::$add_venue,$ret['venue']);

$v_id = self::$DB->lastInsertId();

$ret['spaces'] = array();

foreach($space_array as $space_name){

$values = array($space_name,$v_id);

$this->doStatement(self::$add_space,$values);

$s_id = self::$DB->lastInsertId();

array_unshift($values,$s_id);

$ret['spaces'][] = $values;

}

return $ret;

}

function bookEvent ($space_id,$name,$time,$duration){

$values = array($space_id,$time,($time+$duration));

$stmt = $this->doStatement(self::$check_slot,$values,false);

if($result = $stmt->fetch()){

throw new \woo\base\AppException("double booked! try again");

}

$this->doStatement(self::$add_event,array($name,$space_id,$time,$duration));

}

}

//客户端,使用起来还是比较简便的

$venue = new VenueManager();

$venue->addVenue('test',array('test1','test2','test3'));