<?php
/**
* CSort class file.
*
* @author Qiang Xue <[email protected]>
* @link http://www.yiiframework.com/
* @copyright Copyright © 2008-2011 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
/**
* CSort represents information relevant to sorting.
*
* When data needs to be sorted according to one or several attributes,
* we can use CSort to represent the sorting information and generate
* appropriate hyperlinks that can lead to sort actions.
*
* CSort is designed to be used together with {@link CActiveRecord}.
* When creating a CSort instance, you need to specify {@link modelClass}.
* You can use CSort to generate hyperlinks by calling {@link link}.
* You can also use CSort to modify a {@link CDbCriteria} instance by calling {@link applyOrder} so that
* it can cause the query results to be sorted according to the specified
* attributes.
*
* In order to prevent SQL injection attacks, CSort ensures that only valid model attributes
* can be sorted. This is determined based on {@link modelClass} and {@link attributes}.
* When {@link attributes} is not set, all attributes belonging to {@link modelClass}
* can be sorted. When {@link attributes} is set, only those attributes declared in the property
* can be sorted.
*
* By configuring {@link attributes}, one can perform more complex sorts that may
* consist of things like compound attributes (e.g. sort based on the combination of
* first name and last name of users).
*
* The property {@link attributes} should be an array of key-value pairs, where the keys
* represent the attribute names, while the values represent the virtual attribute definitions.
* For more details, please check the documentation about {@link attributes}.
*
* @property string $orderBy The order-by columns represented by this sort object.
* This can be put in the ORDER BY clause of a SQL statement.
* @property array $directions Sort directions indexed by attribute names.
* The sort direction. Can be either CSort::SORT_ASC for ascending order or
* CSort::SORT_DESC for descending order.
*
* @author Qiang Xue <[email protected]>
* @package system.web
*/
class CSort extends CComponent
{
/**
* Sort ascending
* @since 1.1.10
*/
const SORT_ASC = false;
/**
* Sort descending
* @since 1.1.10
*/
const SORT_DESC = true;
/**
* @var boolean whether the sorting can be applied to multiple attributes simultaneously.
* Defaults to false, which means each time the data can only be sorted by one attribute.
*/
public $multiSort=false;
/**
* @var string the name of the model class whose attributes can be sorted.
* The model class must be a child class of {@link CActiveRecord}.
*/
public $modelClass;
/**
* @var array list of attributes that are allowed to be sorted.
* For example, array('user_id','create_time') would specify that only 'user_id'
* and 'create_time' of the model {@link modelClass} can be sorted.
* By default, this property is an empty array, which means all attributes in
* {@link modelClass} are allowed to be sorted.
*
* This property can also be used to specify complex sorting. To do so,
* a virtual attribute can be declared in terms of a key-value pair in the array.
* The key refers to the name of the virtual attribute that may appear in the sort request,
* while the value specifies the definition of the virtual attribute.
*
* In the simple case, a key-value pair can be like <code>'user'=>'user_id'</code>
* where 'user' is the name of the virtual attribute while 'user_id' means the virtual
* attribute is the 'user_id' attribute in the {@link modelClass}.
*
* A more flexible way is to specify the key-value pair as
* <pre>
* 'user'=>array(
* 'asc'=>'first_name, last_name',
* 'desc'=>'first_name DESC, last_name DESC',
* 'label'=>'Name'
* )
* </pre>
* where 'user' is the name of the virtual attribute that specifies the full name of user
* (a compound attribute consisting of first name and last name of user). In this case,
* we have to use an array to define the virtual attribute with three elements: 'asc',
* 'desc' and 'label'.
*
* The above approach can also be used to declare virtual attributes that consist of relational
* attributes. For example,
* <pre>
* 'price'=>array(
* 'asc'=>'item.price',
* 'desc'=>'item.price DESC',
* 'label'=>'Item Price'
* )
* </pre>
*
* Note, the attribute name should not contain '-' or '.' characters because
* they are used as {@link separators}.
*
* Starting from version 1.1.3, an additional option named 'default' can be used in the virtual attribute
* declaration. This option specifies whether an attribute should be sorted in ascending or descending
* order upon user clicking the corresponding sort hyperlink if it is not currently sorted. The valid
* option values include 'asc' (default) and 'desc'. For example,
* <pre>
* 'price'=>array(
* 'asc'=>'item.price',
* 'desc'=>'item.price DESC',
* 'label'=>'Item Price',
* 'default'=>'desc',
* )
* </pre>
*
* Also starting from version 1.1.3, you can include a star ('*') element in this property so that
* all model attributes are available for sorting, in addition to those virtual attributes. For example,
* <pre>
* 'attributes'=>array(
* 'price'=>array(
* 'asc'=>'item.price',
* 'desc'=>'item.price DESC',
* 'label'=>'Item Price',
* 'default'=>'desc',
* ),
* '*',
* )
* </pre>
* Note that when a name appears as both a model attribute and a virtual attribute, the position of
* the star element in the array determines which one takes precedence. In particular, if the star
* element is the first element in the array, the model attribute takes precedence; and if the star
* element is the last one, the virtual attribute takes precedence.
*/
public $attributes=array();
/**
* @var string the name of the GET parameter that specifies which attributes to be sorted
* in which direction. Defaults to 'sort'.
*/
public $sortVar='sort';
/**
* @var string the tag appeared in the GET parameter that indicates the attribute should be sorted
* in descending order. Defaults to 'desc'.
*/
public $descTag='desc';
/**
* @var mixed the default order that should be applied to the query criteria when
* the current request does not specify any sort. For example, 'name, create_time DESC' or
* 'UPPER(name)'.
*
* Starting from version 1.1.3, you can also specify the default order using an array.
* The array keys could be attribute names or virtual attribute names as declared in {@link attributes},
* and the array values indicate whether the sorting of the corresponding attributes should
* be in descending order. For example,
* <pre>
* 'defaultOrder'=>array(
* 'price'=>CSort::SORT_DESC,
* )
* </pre>
* `SORT_DESC` and `SORT_ASC` are available since 1.1.10. In earlier Yii versions you should use
* `true` and `false` respectively.
*
* Please note when using array to specify the default order, the corresponding attributes
* will be put into {@link directions} and thus affect how the sort links are rendered
* (e.g. an arrow may be displayed next to the currently active sort link).
*/
public $defaultOrder;
/**
* @var string the route (controller ID and action ID) for generating the sorted contents.
* Defaults to empty string, meaning using the currently requested route.
*/
public $route='';
/**
* @var array separators used in the generated URL. This must be an array consisting of
* two elements. The first element specifies the character separating different
* attributes, while the second element specifies the character separating attribute name
* and the corresponding sort direction. Defaults to array('-','.').
*/
public $separators=array('-','.');
/**
* @var array the additional GET parameters (name=>value) that should be used when generating sort URLs.
* Defaults to null, meaning using the currently available GET parameters.
*/
public $params;
private $_directions;
/**
* Constructor.
* @param string $modelClass the class name of data models that need to be sorted.
* This should be a child class of {@link CActiveRecord}.
*/
public function __construct($modelClass=null)
{
$this->modelClass=$modelClass;
}
/**
* Modifies the query criteria by changing its {@link CDbCriteria::order} property.
* This method will use {@link directions} to determine which columns need to be sorted.
* They will be put in the ORDER BY clause. If the criteria already has non-empty {@link CDbCriteria::order} value,
* the new value will be appended to it.
* @param CDbCriteria $criteria the query criteria
*/
public function applyOrder($criteria)
{
$order=$this->getOrderBy($criteria);
if(!empty($order))
{
if(!empty($criteria->order))
$criteria->order.=', ';
$criteria->order.=$order;
}
}
/**
* @param CDbCriteria $criteria the query criteria
* @return string the order-by columns represented by this sort object.
* This can be put in the ORDER BY clause of a SQL statement.
* @since 1.1.0
*/
public function getOrderBy($criteria=null)
{
$directions=$this->getDirections();
if(empty($directions))
return is_string($this->defaultOrder) ? $this->defaultOrder : '';
else
{
if($this->modelClass!==null)
$schema=CActiveRecord::model($this->modelClass)->getDbConnection()->getSchema();
$orders=array();
foreach($directions as $attribute=>$descending)
{
$definition=$this->resolveAttribute($attribute);
if(is_array($definition))
{
if($descending)
$orders[]=isset($definition['desc']) ? $definition['desc'] : $attribute.' DESC';
else
$orders[]=isset($definition['asc']) ? $definition['asc'] : $attribute;
}
elseif($definition!==false)
{
$attribute=$definition;
if(isset($schema))
{
if(($pos=strpos($attribute,'.'))!==false)
$attribute=$schema->quoteTableName(substr($attribute,0,$pos)).'.'.$schema->quoteColumnName(substr($attribute,$pos+1));
else
$attribute=($criteria===null || $criteria->alias===null ? CActiveRecord::model($this->modelClass)->getTableAlias(true) : $schema->quoteTableName($criteria->alias)).'.'.$schema->quoteColumnName($attribute);
}
$orders[]=$descending?$attribute.' DESC':$attribute;
}
}
return implode(', ',$orders);
}
}
/**
* Generates a hyperlink that can be clicked to cause sorting.
* @param string $attribute the attribute name. This must be the actual attribute name, not alias.
* If it is an attribute of a related AR object, the name should be prefixed with
* the relation name (e.g. 'author.name', where 'author' is the relation name).
* @param string $label the link label. If null, the label will be determined according
* to the attribute (see {@link resolveLabel}).
* @param array $htmlOptions additional HTML attributes for the hyperlink tag
* @return string the generated hyperlink
*/
public function link($attribute,$label=null,$htmlOptions=array())
{
if($label===null)
$label=$this->resolveLabel($attribute);
if(($definition=$this->resolveAttribute($attribute))===false)
return $label;
$directions=$this->getDirections();
if(isset($directions[$attribute]))
{
$class=$directions[$attribute] ? 'desc' : 'asc';
if(isset($htmlOptions['class']))
$htmlOptions['class'].=' '.$class;
else
$htmlOptions['class']=$class;
$descending=!$directions[$attribute];
unset($directions[$attribute]);
}
elseif(is_array($definition) && isset($definition['default']))
$descending=$definition['default']==='desc';
else
$descending=false;
if($this->multiSort)
$directions=array_merge(array($attribute=>$descending),$directions);
else
$directions=array($attribute=>$descending);
$url=$this->createUrl(Yii::app()->getController(),$directions);
return $this->createLink($attribute,$label,$url,$htmlOptions);
}
/**
* Resolves the attribute label for the specified attribute.
* This will invoke {@link CActiveRecord::getAttributeLabel} to determine what label to use.
* If the attribute refers to a virtual attribute declared in {@link attributes},
* then the label given in the {@link attributes} will be returned instead.
* @param string $attribute the attribute name.
* @return string the attribute label
*/
public function resolveLabel($attribute)
{
$definition=$this->resolveAttribute($attribute);
if(is_array($definition))
{
if(isset($definition['label']))
return $definition['label'];
}
elseif(is_string($definition))
$attribute=$definition;
if($this->modelClass!==null)
return CActiveRecord::model($this->modelClass)->getAttributeLabel($attribute);
else
return $attribute;
}
/**
* Returns the currently requested sort information.
* @return array sort directions indexed by attribute names.
* Sort direction can be either CSort::SORT_ASC for ascending order or
* CSort::SORT_DESC for descending order.
*/
public function getDirections()
{
if($this->_directions===null)
{
$this->_directions=array();
if(isset($_GET[$this->sortVar]) && is_string($_GET[$this->sortVar]))
{
$attributes=explode($this->separators[0],$_GET[$this->sortVar]);
foreach($attributes as $attribute)
{
if(($pos=strrpos($attribute,$this->separators[1]))!==false)
{
$descending=substr($attribute,$pos+1)===$this->descTag;
if($descending)
$attribute=substr($attribute,0,$pos);
}
else
$descending=false;
if(($this->resolveAttribute($attribute))!==false)
{
$this->_directions[$attribute]=$descending;
if(!$this->multiSort)
return $this->_directions;
}
}
}
if($this->_directions===array() && is_array($this->defaultOrder))
$this->_directions=$this->defaultOrder;
}
return $this->_directions;
}
/**
* Returns the sort direction of the specified attribute in the current request.
* @param string $attribute the attribute name
* @return mixed Sort direction of the attribute. Can be either CSort::SORT_ASC
* for ascending order or CSort::SORT_DESC for descending order. Value is null
* if the attribute doesn't need to be sorted.
*/
public function getDirection($attribute)
{
$this->getDirections();
return isset($this->_directions[$attribute]) ? $this->_directions[$attribute] : null;
}
/**
* Creates a URL that can lead to generating sorted data.
* @param CController $controller the controller that will be used to create the URL.
* @param array $directions the sort directions indexed by attribute names.
* The sort direction can be either CSort::SORT_ASC for ascending order or
* CSort::SORT_DESC for descending order.
* @return string the URL for sorting
*/
public function createUrl($controller,$directions)
{
$sorts=array();
foreach($directions as $attribute=>$descending)
$sorts[]=$descending ? $attribute.$this->separators[1].$this->descTag : $attribute;
$params=$this->params===null ? $_GET : $this->params;
$params[$this->sortVar]=implode($this->separators[0],$sorts);
return $controller->createUrl($this->route,$params);
}
/**
* Returns the real definition of an attribute given its name.
*
* The resolution is based on {@link attributes} and {@link CActiveRecord::attributeNames}.
* <ul>
* <li>When {@link attributes} is an empty array, if the name refers to an attribute of {@link modelClass},
* then the name is returned back.</li>
* <li>When {@link attributes} is not empty, if the name refers to an attribute declared in {@link attributes},
* then the corresponding virtual attribute definition is returned. Starting from version 1.1.3, if {@link attributes}
* contains a star ('*') element, the name will also be used to match against all model attributes.</li>
* <li>In all other cases, false is returned, meaning the name does not refer to a valid attribute.</li>
* </ul>
* @param string $attribute the attribute name that the user requests to sort on
* @return mixed the attribute name or the virtual attribute definition. False if the attribute cannot be sorted.
*/
public function resolveAttribute($attribute)
{
if($this->attributes!==array())
$attributes=$this->attributes;
elseif($this->modelClass!==null)
$attributes=CActiveRecord::model($this->modelClass)->attributeNames();
else
return false;
foreach($attributes as $name=>$definition)
{
if(is_string($name))
{
if($name===$attribute)
return $definition;
}
elseif($definition==='*')
{
if($this->modelClass!==null && CActiveRecord::model($this->modelClass)->hasAttribute($attribute))
return $attribute;
}
elseif($definition===$attribute)
return $attribute;
}
return false;
}
/**
* Creates a hyperlink based on the given label and URL.
* You may override this method to customize the link generation.
* @param string $attribute the name of the attribute that this link is for
* @param string $label the label of the hyperlink
* @param string $url the URL
* @param array $htmlOptions additional HTML options
* @return string the generated hyperlink
*/
protected function createLink($attribute,$label,$url,$htmlOptions)
{
return CHtml::link($label,$url,$htmlOptions);
}
}