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authorctrlaltca <>2012-07-12 11:21:01 +0000
committerctrlaltca <>2012-07-12 11:21:01 +0000
commit903ae8a581fac1e6917fc3e31d2ad8fb91df80c3 (patch)
treee08bf04f0823650a231227ac3499121270172a23 /framework/Collections/TPriorityList.php
parent3e4e6e66aeb3f8fea4e1eb4237498ef9d2358f63 (diff)
standardize the use of unix eol; use svn properties to enforce native eol
Diffstat (limited to 'framework/Collections/TPriorityList.php')
-rw-r--r--framework/Collections/TPriorityList.php1486
1 files changed, 743 insertions, 743 deletions
diff --git a/framework/Collections/TPriorityList.php b/framework/Collections/TPriorityList.php
index 5258e802..a174ed13 100644
--- a/framework/Collections/TPriorityList.php
+++ b/framework/Collections/TPriorityList.php
@@ -1,743 +1,743 @@
-<?php
-/**
- * TPriorityList, TPriorityListIterator classes
- *
- * @author Brad Anderson <javalizard@gmail.com>
- * @link http://www.pradosoft.com/
- * @copyright Copyright &copy; 2005-2012 PradoSoft
- * @license http://www.pradosoft.com/license/
- * @version $Id: TPriorityList.php 2541 2008-10-21 15:05:13Z javalizard $
- * @package System.Collections
- */
-
-/**
- * TPriorityList class
- *
- * TPriorityList implements a priority ordered list collection class. It allows you to specify
- * any numeric for priorities down to a specific precision. The lower the numeric, the high the priority of the item in the
- * list. Thus -10 has a higher priority than -5, 0, 10 (the default), 18, 10005, etc. Per {@link round}, precision may be negative and
- * thus rounding can go by 10, 100, 1000, etc, instead of just .1, .01, .001, etc. The default precision allows for 8 decimal
- * places. There is also a default priority of 10, if no different default priority is specified or no item specific priority is indicated.
- * If you replace TList with this class it will work exactly the same with items inserted set to the default priority, until you start
- * using different priorities than the default priority.
- *
- * As you access the PHP array features of this class, it flattens and caches the results. If at all possible, this
- * will keep the cache fresh even when manipulated. If this is not possible the cache is cleared.
- * When an array of items are needed and the cache is outdated, the cache is recreated from the items and their priorities
- *
- * You can access, append, insert, remove an item by using
- * {@link itemAt}, {@link add}, {@link insertAt}, and {@link remove}.
- * To get the number of the items in the list, use {@link getCount}.
- * TPriorityList can also be used like a regular array as follows,
- * <code>
- * $list[]=$item; // append with the default priority. It may not be the last item if other items in the list are prioritized after the default priority
- * $list[$index]=$item; // $index must be between 0 and $list->Count-1. This sets the element regardless of priority. Priority stays the same.
- * $list[$index]=$item; // $index is $list->Count. This appends the item to the end of the list with the same priority as the last item in the list.
- * unset($list[$index]); // remove the item at $index
- * if(isset($list[$index])) // if the list has an item at $index
- * foreach($list as $index=>$item) // traverse each item in the list in proper priority order and add/insert order
- * $n=count($list); // returns the number of items in the list
- * </code>
- *
- * To extend TPriorityList for doing your own operations with each addition or removal,
- * override {@link insertAtIndexInPriority()} and {@link removeAtIndexInPriority()} and then call the parent.
- *
- * @author Brad Anderson <javalizard@gmail.com>
- * @version $Id: TPriorityList.php 2541 2008-10-21 15:05:13Z javalizard $
- * @package System.Collections
- * @since 3.2a
- */
-class TPriorityList extends TList
-{
- /**
- * @var array internal data storage
- */
- private $_d=array();
- /**
- * @var boolean indicates if the _d is currently ordered.
- */
- private $_o=false;
- /**
- * @var array cached flattened internal data storage
- */
- private $_fd=null;
- /**
- * @var integer number of items contain within the list
- */
- private $_c=0;
- /**
- * @var numeric the default priority of items without specified priorities
- */
- private $_dp=10;
- /**
- * @var integer the precision of the numeric priorities within this priority list.
- */
- private $_p=8;
-
- /**
- * Constructor.
- * Initializes the list with an array or an iterable object.
- * @param array|Iterator the intial data. Default is null, meaning no initial data.
- * @param boolean whether the list is read-only
- * @param numeric the default priority of items without specified priorities.
- * @param integer the precision of the numeric priorities
- * @throws TInvalidDataTypeException If data is not null and is neither an array nor an iterator.
- */
- public function __construct($data=null,$readOnly=false,$defaultPriority=10,$precision=8)
- {
- parent::__construct();
- if($data!==null)
- $this->copyFrom($data);
- $this->setReadOnly($readOnly);
- $this->setPrecision($precision);
- $this->setDefaultPriority($defaultPriority);
- }
-
- /**
- * Returns the number of items in the list.
- * This method is required by Countable interface.
- * @return integer number of items in the list.
- */
- public function count()
- {
- return $this->getCount();
- }
-
- /**
- * Returns the total number of items in the list
- * @return integer the number of items in the list
- */
- public function getCount()
- {
- return $this->_c;
- }
-
- /**
- * Gets the number of items at a priority within the list
- * @param numeric optional priority at which to count items. if no parameter, it will be set to the default {@link getDefaultPriority}
- * @return integer the number of items in the list at the specified priority
- */
- public function getPriorityCount($priority=null)
- {
- if($priority===null)
- $priority=$this->getDefaultPriority();
- $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
-
- if(!isset($this->_d[$priority]) || !is_array($this->_d[$priority]))
- return false;
- return count($this->_d[$priority]);
- }
-
- /**
- * @return numeric gets the default priority of inserted items without a specified priority
- */
- public function getDefaultPriority()
- {
- return $this->_dp;
- }
-
- /**
- * This must be called internally or when instantiated.
- * @param numeric sets the default priority of inserted items without a specified priority
- */
- protected function setDefaultPriority($value)
- {
- $this->_dp=(string)round(TPropertyValue::ensureFloat($value),$this->_p);
- }
-
- /**
- * @return integer The precision of numeric priorities, defaults to 8
- */
- public function getPrecision()
- {
- return $this->_p;
- }
-
- /**
- * This must be called internally or when instantiated.
- * @param integer The precision of numeric priorities.
- */
- protected function setPrecision($value)
- {
- $this->_p=TPropertyValue::ensureInteger($value);
- }
-
- /**
- * Returns an iterator for traversing the items in the list.
- * This method is required by the interface IteratorAggregate.
- * @return Iterator an iterator for traversing the items in the list.
- */
- public function getIterator()
- {
- return new ArrayIterator($this->flattenPriorities());
- }
-
- /**
- * This returns a list of the priorities within this list, ordered lowest to highest.
- * @return array the array of priority numerics in decreasing priority order
- */
- public function getPriorities()
- {
- $this->sortPriorities();
- return array_keys($this->_d);
- }
-
-
- /**
- * This orders the priority list internally.
- */
- protected function sortPriorities() {
- if(!$this->_o) {
- ksort($this->_d,SORT_NUMERIC);
- $this->_o=true;
- }
- }
-
- /**
- * This flattens the priority list into a flat array [0,...,n-1]
- * @return array array of items in the list in priority and index order
- */
- protected function flattenPriorities() {
- if(is_array($this->_fd))
- return $this->_fd;
-
- $this->sortPriorities();
- $this->_fd=array();
- foreach($this->_d as $priority => $itemsatpriority)
- $this->_fd=array_merge($this->_fd,$itemsatpriority);
- return $this->_fd;
- }
-
-
- /**
- * Returns the item at the index of a flattened priority list.
- * {@link offsetGet} calls this method.
- * @param integer the index of the item to get
- * @return mixed the element at the offset
- * @throws TInvalidDataValueException Issued when the index is invalid
- */
- public function itemAt($index)
- {
- if($index>=0&&$index<$this->getCount()) {
- $arr=$this->flattenPriorities();
- return $arr[$index];
- } else
- throw new TInvalidDataValueException('list_index_invalid',$index);
- }
-
- /**
- * Gets all the items at a specific priority.
- * @param numeric priority of the items to get. Defaults to null, filled in with the default priority, if left blank.
- * @return array all items at priority in index order, null if there are no items at that priority
- */
- public function itemsAtPriority($priority=null)
- {
- if($priority===null)
- $priority=$this->getDefaultPriority();
- $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
-
- return isset($this->_d[$priority])?$this->_d[$priority]:null;
- }
-
- /**
- * Returns the item at an index within a priority
- * @param integer the index into the list of items at priority
- * @param numeric the priority which to index. no parameter or null will result in the default priority
- * @return mixed the element at the offset, false if no element is found at the offset
- */
- public function itemAtIndexInPriority($index,$priority=null)
- {
- if($priority===null)
- $priority=$this->getDefaultPriority();
- $priority=(string)round(TPropertyValue::ensureFloat($priority), $this->_p);
-
- return !isset($this->_d[$priority])?false:(
- isset($this->_d[$priority][$index])?$this->_d[$priority][$index]:false
- );
- }
-
- /**
- * Appends an item into the list at the end of the specified priority. The position of the added item may
- * not be at the end of the list.
- * @param mixed item to add into the list at priority
- * @param numeric priority blank or null for the default priority
- * @return int the index within the flattened array
- * @throws TInvalidOperationException if the map is read-only
- */
- public function add($item,$priority=null)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- return $this->insertAtIndexInPriority($item,false,$priority,true);
- }
-
- /**
- * Inserts an item at an index. It reads the priority of the item at index within the flattened list
- * and then inserts the item at that priority-index.
- * @param integer the specified position in the flattened list.
- * @param mixed new item to add
- * @throws TInvalidDataValueException If the index specified exceeds the bound
- * @throws TInvalidOperationException if the list is read-only
- */
- public function insertAt($index,$item)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if(($priority=$this->priorityAt($index,true))!==false)
- $this->insertAtIndexInPriority($item,$priority[1],$priority[0]);
- else
- throw new TInvalidDataValueException('list_index_invalid',$index);
- }
-
- /**
- * Inserts an item at the specified index within a priority. Override and call this method to
- * insert your own functionality.
- * @param mixed item to add within the list.
- * @param integer index within the priority to add the item, defaults to false which appends the item at the priority
- * @param numeric priority priority of the item. defaults to null, which sets it to the default priority
- * @param boolean preserveCache specifies if this is a special quick function or not. This defaults to false.
- * @throws TInvalidDataValueException If the index specified exceeds the bound
- * @throws TInvalidOperationException if the list is read-only
- */
- public function insertAtIndexInPriority($item,$index=false,$priority=null,$preserveCache=false)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if($priority===null)
- $priority=$this->getDefaultPriority();
- $priority=(string)round(TPropertyValue::ensureFloat($priority), $this->_p);
-
- if($preserveCache) {
- $this->sortPriorities();
- $cc=0;
- foreach($this->_d as $prioritykey=>$items)
- if($prioritykey>=$priority)
- break;
- else
- $cc+=count($items);
-
- if($index===false&&isset($this->_d[$priority])) {
- $c=count($this->_d[$priority]);
- $c+=$cc;
- $this->_d[$priority][]=$item;
- } else if(isset($this->_d[$priority])) {
- $c=$index+$cc;
- array_splice($this->_d[$priority],$index,0,array($item));
- } else {
- $c = $cc;
- $this->_o = false;
- $this->_d[$priority]=array($item);
- }
-
- if($this->_fd&&is_array($this->_fd)) // if there is a flattened array cache
- array_splice($this->_fd,$c,0,array($item));
- } else {
- $c=null;
- if($index===false&&isset($this->_d[$priority])) {
- $cc=count($this->_d[$priority]);
- $this->_d[$priority][]=$item;
- } else if(isset($this->_d[$priority])) {
- $cc=$index;
- array_splice($this->_d[$priority],$index,0,array($item));
- } else {
- $cc=0;
- $this->_o=false;
- $this->_d[$priority]=array($item);
- }
- if($this->_fd&&is_array($this->_fd)&&count($this->_d)==1)
- array_splice($this->_fd,$cc,0,array($item));
- else
- $this->_fd=null;
- }
-
- $this->_c++;
-
- return $c;
-
- }
-
-
- /**
- * Removes an item from the priority list.
- * The list will search for the item. The first matching item found will be removed from the list.
- * @param mixed item the item to be removed.
- * @param numeric priority of item to remove. without this parameter it defaults to false.
- * A value of false means any priority. null will be filled in with the default priority.
- * @return integer index within the flattened list at which the item is being removed
- * @throws TInvalidDataValueException If the item does not exist
- */
- public function remove($item,$priority=false)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if(($p=$this->priorityOf($item,true))!==false)
- {
- if($priority!==false) {
- if($priority===null)
- $priority=$this->getDefaultPriority();
- $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
-
- if($p[0]!=$priority)
- throw new TInvalidDataValueException('list_item_inexistent');
- }
- $this->removeAtIndexInPriority($p[1],$p[0]);
- return $p[2];
- }
- else
- throw new TInvalidDataValueException('list_item_inexistent');
- }
-
- /**
- * Removes an item at the specified index in the flattened list.
- * @param integer index of the item to be removed.
- * @return mixed the removed item.
- * @throws TInvalidDataValueException If the index specified exceeds the bound
- * @throws TInvalidOperationException if the list is read-only
- */
- public function removeAt($index)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if(($priority=$this->priorityAt($index, true))!==false)
- return $this->removeAtIndexInPriority($priority[1],$priority[0]);
- throw new TInvalidDataValueException('list_index_invalid',$index);
- }
-
- /**
- * Removes the item at a specific index within a priority. Override
- * and call this method to insert your own functionality.
- * @param integer index of item to remove within the priority.
- * @param numeric priority of the item to remove, defaults to null, or left blank, it is then set to the default priority
- * @return mixed the removed item.
- * @throws TInvalidDataValueException If the item does not exist
- */
- public function removeAtIndexInPriority($index, $priority=null)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if($priority===null)
- $priority=$this->getDefaultPriority();
- $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
-
- if(!isset($this->_d[$priority])||$index<0||$index>=count($this->_d[$priority]))
- throw new TInvalidDataValueException('list_item_inexistent');
-
- // $value is an array of elements removed, only one
- $value=array_splice($this->_d[$priority],$index,1);
- $value=$value[0];
-
- if(!count($this->_d[$priority]))
- unset($this->_d[$priority]);
-
- $this->_c--;
- $this->_fd=null;
- return $value;
- }
-
- /**
- * Removes all items in the priority list by calling removeAtIndexInPriority from the last item to the first.
- */
- public function clear()
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- $d=array_reverse($this->_d,true);
- foreach($this->_d as $priority=>$items) {
- for($index=count($items)-1;$index>=0;$index--)
- $this->removeAtIndexInPriority($index,$priority);
- unset($this->_d[$priority]);
- }
- }
-
- /**
- * @param mixed item
- * @return boolean whether the list contains the item
- */
- public function contains($item)
- {
- return $this->indexOf($item)>=0;
- }
-
- /**
- * @param mixed item
- * @return integer the index of the item in the flattened list (0 based), -1 if not found.
- */
- public function indexOf($item)
- {
- if(($index=array_search($item,$this->flattenPriorities(),true))===false)
- return -1;
- else
- return $index;
- }
-
- /**
- * Returns the priority of a particular item
- * @param mixed the item to look for within the list
- * @param boolean withindex this specifies if the full positional data of the item within the list is returned.
- * This defaults to false, if no parameter is provided, so only provides the priority number of the item by default.
- * @return numeric|array the priority of the item in the list, false if not found.
- * if withindex is true, an array is returned of [0 => $priority, 1 => $priorityIndex, 2 => flattenedIndex,
- * 'priority' => $priority, 'index' => $priorityIndex, 'absindex' => flattenedIndex]
- */
- public function priorityOf($item,$withindex = false)
- {
- $this->sortPriorities();
-
- $absindex = 0;
- foreach($this->_d as $priority=>$items) {
- if(($index=array_search($item,$items,true))!==false) {
- $absindex+=$index;
- return $withindex?array($priority,$index,$absindex,
- 'priority'=>$priority,'index'=>$index,'absindex'=>$absindex):$priority;
- } else
- $absindex+=count($items);
- }
-
- return false;
- }
-
- /**
- * Retutrns the priority of an item at a particular flattened index.
- * @param integer index of the item within the list
- * @param boolean withindex this specifies if the full positional data of the item within the list is returned.
- * This defaults to false, if no parameter is provided, so only provides the priority number of the item by default.
- * @return numeric|array the priority of the item in the list, false if not found.
- * if withindex is true, an array is returned of [0 => $priority, 1 => $priorityIndex, 2 => flattenedIndex,
- * 'priority' => $priority, 'index' => $priorityIndex, 'absindex' => flattenedIndex]
- */
- public function priorityAt($index,$withindex = false)
- {
- if($index<0||$index>=$this->getCount())
- throw new TInvalidDataValueException('list_index_invalid',$index);
-
- $absindex=$index;
- $this->sortPriorities();
- foreach($this->_d as $priority=>$items) {
- if($index>=($c=count($items)))
- $index-=$c;
- else
- return $withindex?array($priority,$index,$absindex,
- 'priority'=>$priority,'index'=>$index,'absindex'=>$absindex):$priority;
- }
- return false;
- }
-
- /**
- * This inserts an item before another item within the list. It uses the same priority as the
- * found index item and places the new item before it.
- * @param mixed indexitem the item to index
- * @param mixed the item to add before indexitem
- * @return integer where the item has been inserted in the flattened list
- * @throws TInvalidDataValueException If the item does not exist
- */
- public function insertBefore($indexitem, $item)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if(($priority=$this->priorityOf($indexitem,true))===false)
- throw new TInvalidDataValueException('list_item_inexistent');
-
- $this->insertAtIndexInPriority($item,$priority[1],$priority[0]);
-
- return $priority[2];
- }
-
- /**
- * This inserts an item after another item within the list. It uses the same priority as the
- * found index item and places the new item after it.
- * @param mixed indexitem the item to index
- * @param mixed the item to add after indexitem
- * @return integer where the item has been inserted in the flattened list
- * @throws TInvalidDataValueException If the item does not exist
- */
- public function insertAfter($indexitem, $item)
- {
- if($this->getReadOnly())
- throw new TInvalidOperationException('list_readonly',get_class($this));
-
- if(($priority=$this->priorityOf($indexitem,true))===false)
- throw new TInvalidDataValueException('list_item_inexistent');
-
- $this->insertAtIndexInPriority($item,$priority[1]+1,$priority[0]);
-
- return $priority[2]+1;
- }
-
- /**
- * @return array the priority list of items in array
- */
- public function toArray()
- {
- return $this->flattenPriorities();
- }
-
- /**
- * @return array the array of priorities keys with values of arrays of items. The priorities are sorted so important priorities, lower numerics, are first.
- */
- public function toPriorityArray()
- {
- $this->sortPriorities();
- return $this->_d;
- }
-
- /**
- * Combines the map elements which have a priority below the parameter value
- * @param numeric the cut-off priority. All items of priority less than this are returned.
- * @param boolean whether or not the input cut-off priority is inclusive. Default: false, not inclusive.
- * @return array the array of priorities keys with values of arrays of items that are below a specified priority.
- * The priorities are sorted so important priorities, lower numerics, are first.
- */
- public function toArrayBelowPriority($priority,$inclusive=false)
- {
- $this->sortPriorities();
- $items=array();
- foreach($this->_d as $itemspriority=>$itemsatpriority)
- {
- if((!$inclusive&&$itemspriority>=$priority)||$itemspriority>$priority)
- break;
- $items=array_merge($items,$itemsatpriority);
- }
- return $items;
- }
-
- /**
- * Combines the map elements which have a priority above the parameter value
- * @param numeric the cut-off priority. All items of priority greater than this are returned.
- * @param boolean whether or not the input cut-off priority is inclusive. Default: true, inclusive.
- * @return array the array of priorities keys with values of arrays of items that are above a specified priority.
- * The priorities are sorted so important priorities, lower numerics, are first.
- */
- public function toArrayAbovePriority($priority,$inclusive=true)
- {
- $this->sortPriorities();
- $items=array();
- foreach($this->_d as $itemspriority=>$itemsatpriority)
- {
- if((!$inclusive&&$itemspriority<=$priority)||$itemspriority<$priority)
- continue;
- $items=array_merge($items,$itemsatpriority);
- }
- return $items;
- }
-
-
- /**
- * Copies iterable data into the priority list.
- * Note, existing data in the map will be cleared first.
- * @param mixed the data to be copied from, must be an array or object implementing Traversable
- * @throws TInvalidDataTypeException If data is neither an array nor an iterator.
- */
- public function copyFrom($data)
- {
- if($data instanceof TPriorityList)
- {
- if($this->getCount()>0)
- $this->clear();
- foreach($data->getPriorities() as $priority)
- {
- foreach($data->itemsAtPriority($priority) as $index=>$item)
- $this->insertAtIndexInPriority($item,$index,$priority);
- }
- } else if(is_array($data)||$data instanceof Traversable) {
- if($this->getCount()>0)
- $this->clear();
- foreach($data as $key=>$item)
- $this->add($item);
- } else if($data!==null)
- throw new TInvalidDataTypeException('map_data_not_iterable');
- }
-
- /**
- * Merges iterable data into the priority list.
- * New data will be appended to the end of the existing data. If another TPriorityList is merged,
- * the incoming parameter items will be appended at the priorities they are present. These items will be added
- * to the end of the existing items with equal priorities, if there are any.
- * @param mixed the data to be merged with, must be an array or object implementing Traversable
- * @throws TInvalidDataTypeException If data is neither an array nor an iterator.
- */
- public function mergeWith($data)
- {
- if($data instanceof TPriorityList)
- {
- foreach($data->getPriorities() as $priority)
- {
- foreach($data->itemsAtPriority($priority) as $index=>$item)
- $this->insertAtIndexInPriority($item,false,$priority);
- }
- }
- else if(is_array($data)||$data instanceof Traversable)
- {
- foreach($data as $priority=>$item)
- $this->add($item);
-
- }
- else if($data!==null)
- throw new TInvalidDataTypeException('map_data_not_iterable');
- }
-
- /**
- * Returns whether there is an element at the specified offset.
- * This method is required by the interface ArrayAccess.
- * @param mixed the offset to check on
- * @return boolean
- */
- public function offsetExists($offset)
- {
- return ($offset>=0&&$offset<$this->getCount());
- }
-
- /**
- * Returns the element at the specified offset.
- * This method is required by the interface ArrayAccess.
- * @param integer the offset to retrieve element.
- * @return mixed the element at the offset, null if no element is found at the offset
- */
- public function offsetGet($offset)
- {
- return $this->itemAt($offset);
- }
-
- /**
- * Sets the element at the specified offset. This method is required by the interface ArrayAccess.
- * Setting elements in a priority list is not straight forword when appending and setting at the
- * end boundary. When appending without an offset (a null offset), the item will be added at
- * the default priority. The item may not be the last item in the list. When appending with an
- * offset equal to the count of the list, the item will get be appended with the last items priority.
- *
- * All together, when setting the location of an item, the item stays in that location, but appending
- * an item into a priority list doesn't mean the item is at the end of the list.
- * @param integer the offset to set element
- * @param mixed the element value
- */
- public function offsetSet($offset,$item)
- {
- if($offset===null)
- return $this->add($item);
- if($offset===$this->getCount()) {
- $priority=$this->priorityAt($offset-1,true);
- $priority[1]++;
- } else {
- $priority=$this->priorityAt($offset,true);
- $this->removeAtIndexInPriority($priority[1],$priority[0]);
- }
- $this->insertAtIndexInPriority($item,$priority[1],$priority[0]);
- }
-
- /**
- * Unsets the element at the specified offset.
- * This method is required by the interface ArrayAccess.
- * @param mixed the offset to unset element
- */
- public function offsetUnset($offset)
- {
- $this->removeAt($offset);
- }
-}
+<?php
+/**
+ * TPriorityList, TPriorityListIterator classes
+ *
+ * @author Brad Anderson <javalizard@gmail.com>
+ * @link http://www.pradosoft.com/
+ * @copyright Copyright &copy; 2005-2012 PradoSoft
+ * @license http://www.pradosoft.com/license/
+ * @version $Id: TPriorityList.php 2541 2008-10-21 15:05:13Z javalizard $
+ * @package System.Collections
+ */
+
+/**
+ * TPriorityList class
+ *
+ * TPriorityList implements a priority ordered list collection class. It allows you to specify
+ * any numeric for priorities down to a specific precision. The lower the numeric, the high the priority of the item in the
+ * list. Thus -10 has a higher priority than -5, 0, 10 (the default), 18, 10005, etc. Per {@link round}, precision may be negative and
+ * thus rounding can go by 10, 100, 1000, etc, instead of just .1, .01, .001, etc. The default precision allows for 8 decimal
+ * places. There is also a default priority of 10, if no different default priority is specified or no item specific priority is indicated.
+ * If you replace TList with this class it will work exactly the same with items inserted set to the default priority, until you start
+ * using different priorities than the default priority.
+ *
+ * As you access the PHP array features of this class, it flattens and caches the results. If at all possible, this
+ * will keep the cache fresh even when manipulated. If this is not possible the cache is cleared.
+ * When an array of items are needed and the cache is outdated, the cache is recreated from the items and their priorities
+ *
+ * You can access, append, insert, remove an item by using
+ * {@link itemAt}, {@link add}, {@link insertAt}, and {@link remove}.
+ * To get the number of the items in the list, use {@link getCount}.
+ * TPriorityList can also be used like a regular array as follows,
+ * <code>
+ * $list[]=$item; // append with the default priority. It may not be the last item if other items in the list are prioritized after the default priority
+ * $list[$index]=$item; // $index must be between 0 and $list->Count-1. This sets the element regardless of priority. Priority stays the same.
+ * $list[$index]=$item; // $index is $list->Count. This appends the item to the end of the list with the same priority as the last item in the list.
+ * unset($list[$index]); // remove the item at $index
+ * if(isset($list[$index])) // if the list has an item at $index
+ * foreach($list as $index=>$item) // traverse each item in the list in proper priority order and add/insert order
+ * $n=count($list); // returns the number of items in the list
+ * </code>
+ *
+ * To extend TPriorityList for doing your own operations with each addition or removal,
+ * override {@link insertAtIndexInPriority()} and {@link removeAtIndexInPriority()} and then call the parent.
+ *
+ * @author Brad Anderson <javalizard@gmail.com>
+ * @version $Id: TPriorityList.php 2541 2008-10-21 15:05:13Z javalizard $
+ * @package System.Collections
+ * @since 3.2a
+ */
+class TPriorityList extends TList
+{
+ /**
+ * @var array internal data storage
+ */
+ private $_d=array();
+ /**
+ * @var boolean indicates if the _d is currently ordered.
+ */
+ private $_o=false;
+ /**
+ * @var array cached flattened internal data storage
+ */
+ private $_fd=null;
+ /**
+ * @var integer number of items contain within the list
+ */
+ private $_c=0;
+ /**
+ * @var numeric the default priority of items without specified priorities
+ */
+ private $_dp=10;
+ /**
+ * @var integer the precision of the numeric priorities within this priority list.
+ */
+ private $_p=8;
+
+ /**
+ * Constructor.
+ * Initializes the list with an array or an iterable object.
+ * @param array|Iterator the intial data. Default is null, meaning no initial data.
+ * @param boolean whether the list is read-only
+ * @param numeric the default priority of items without specified priorities.
+ * @param integer the precision of the numeric priorities
+ * @throws TInvalidDataTypeException If data is not null and is neither an array nor an iterator.
+ */
+ public function __construct($data=null,$readOnly=false,$defaultPriority=10,$precision=8)
+ {
+ parent::__construct();
+ if($data!==null)
+ $this->copyFrom($data);
+ $this->setReadOnly($readOnly);
+ $this->setPrecision($precision);
+ $this->setDefaultPriority($defaultPriority);
+ }
+
+ /**
+ * Returns the number of items in the list.
+ * This method is required by Countable interface.
+ * @return integer number of items in the list.
+ */
+ public function count()
+ {
+ return $this->getCount();
+ }
+
+ /**
+ * Returns the total number of items in the list
+ * @return integer the number of items in the list
+ */
+ public function getCount()
+ {
+ return $this->_c;
+ }
+
+ /**
+ * Gets the number of items at a priority within the list
+ * @param numeric optional priority at which to count items. if no parameter, it will be set to the default {@link getDefaultPriority}
+ * @return integer the number of items in the list at the specified priority
+ */
+ public function getPriorityCount($priority=null)
+ {
+ if($priority===null)
+ $priority=$this->getDefaultPriority();
+ $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
+
+ if(!isset($this->_d[$priority]) || !is_array($this->_d[$priority]))
+ return false;
+ return count($this->_d[$priority]);
+ }
+
+ /**
+ * @return numeric gets the default priority of inserted items without a specified priority
+ */
+ public function getDefaultPriority()
+ {
+ return $this->_dp;
+ }
+
+ /**
+ * This must be called internally or when instantiated.
+ * @param numeric sets the default priority of inserted items without a specified priority
+ */
+ protected function setDefaultPriority($value)
+ {
+ $this->_dp=(string)round(TPropertyValue::ensureFloat($value),$this->_p);
+ }
+
+ /**
+ * @return integer The precision of numeric priorities, defaults to 8
+ */
+ public function getPrecision()
+ {
+ return $this->_p;
+ }
+
+ /**
+ * This must be called internally or when instantiated.
+ * @param integer The precision of numeric priorities.
+ */
+ protected function setPrecision($value)
+ {
+ $this->_p=TPropertyValue::ensureInteger($value);
+ }
+
+ /**
+ * Returns an iterator for traversing the items in the list.
+ * This method is required by the interface IteratorAggregate.
+ * @return Iterator an iterator for traversing the items in the list.
+ */
+ public function getIterator()
+ {
+ return new ArrayIterator($this->flattenPriorities());
+ }
+
+ /**
+ * This returns a list of the priorities within this list, ordered lowest to highest.
+ * @return array the array of priority numerics in decreasing priority order
+ */
+ public function getPriorities()
+ {
+ $this->sortPriorities();
+ return array_keys($this->_d);
+ }
+
+
+ /**
+ * This orders the priority list internally.
+ */
+ protected function sortPriorities() {
+ if(!$this->_o) {
+ ksort($this->_d,SORT_NUMERIC);
+ $this->_o=true;
+ }
+ }
+
+ /**
+ * This flattens the priority list into a flat array [0,...,n-1]
+ * @return array array of items in the list in priority and index order
+ */
+ protected function flattenPriorities() {
+ if(is_array($this->_fd))
+ return $this->_fd;
+
+ $this->sortPriorities();
+ $this->_fd=array();
+ foreach($this->_d as $priority => $itemsatpriority)
+ $this->_fd=array_merge($this->_fd,$itemsatpriority);
+ return $this->_fd;
+ }
+
+
+ /**
+ * Returns the item at the index of a flattened priority list.
+ * {@link offsetGet} calls this method.
+ * @param integer the index of the item to get
+ * @return mixed the element at the offset
+ * @throws TInvalidDataValueException Issued when the index is invalid
+ */
+ public function itemAt($index)
+ {
+ if($index>=0&&$index<$this->getCount()) {
+ $arr=$this->flattenPriorities();
+ return $arr[$index];
+ } else
+ throw new TInvalidDataValueException('list_index_invalid',$index);
+ }
+
+ /**
+ * Gets all the items at a specific priority.
+ * @param numeric priority of the items to get. Defaults to null, filled in with the default priority, if left blank.
+ * @return array all items at priority in index order, null if there are no items at that priority
+ */
+ public function itemsAtPriority($priority=null)
+ {
+ if($priority===null)
+ $priority=$this->getDefaultPriority();
+ $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
+
+ return isset($this->_d[$priority])?$this->_d[$priority]:null;
+ }
+
+ /**
+ * Returns the item at an index within a priority
+ * @param integer the index into the list of items at priority
+ * @param numeric the priority which to index. no parameter or null will result in the default priority
+ * @return mixed the element at the offset, false if no element is found at the offset
+ */
+ public function itemAtIndexInPriority($index,$priority=null)
+ {
+ if($priority===null)
+ $priority=$this->getDefaultPriority();
+ $priority=(string)round(TPropertyValue::ensureFloat($priority), $this->_p);
+
+ return !isset($this->_d[$priority])?false:(
+ isset($this->_d[$priority][$index])?$this->_d[$priority][$index]:false
+ );
+ }
+
+ /**
+ * Appends an item into the list at the end of the specified priority. The position of the added item may
+ * not be at the end of the list.
+ * @param mixed item to add into the list at priority
+ * @param numeric priority blank or null for the default priority
+ * @return int the index within the flattened array
+ * @throws TInvalidOperationException if the map is read-only
+ */
+ public function add($item,$priority=null)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ return $this->insertAtIndexInPriority($item,false,$priority,true);
+ }
+
+ /**
+ * Inserts an item at an index. It reads the priority of the item at index within the flattened list
+ * and then inserts the item at that priority-index.
+ * @param integer the specified position in the flattened list.
+ * @param mixed new item to add
+ * @throws TInvalidDataValueException If the index specified exceeds the bound
+ * @throws TInvalidOperationException if the list is read-only
+ */
+ public function insertAt($index,$item)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if(($priority=$this->priorityAt($index,true))!==false)
+ $this->insertAtIndexInPriority($item,$priority[1],$priority[0]);
+ else
+ throw new TInvalidDataValueException('list_index_invalid',$index);
+ }
+
+ /**
+ * Inserts an item at the specified index within a priority. Override and call this method to
+ * insert your own functionality.
+ * @param mixed item to add within the list.
+ * @param integer index within the priority to add the item, defaults to false which appends the item at the priority
+ * @param numeric priority priority of the item. defaults to null, which sets it to the default priority
+ * @param boolean preserveCache specifies if this is a special quick function or not. This defaults to false.
+ * @throws TInvalidDataValueException If the index specified exceeds the bound
+ * @throws TInvalidOperationException if the list is read-only
+ */
+ public function insertAtIndexInPriority($item,$index=false,$priority=null,$preserveCache=false)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if($priority===null)
+ $priority=$this->getDefaultPriority();
+ $priority=(string)round(TPropertyValue::ensureFloat($priority), $this->_p);
+
+ if($preserveCache) {
+ $this->sortPriorities();
+ $cc=0;
+ foreach($this->_d as $prioritykey=>$items)
+ if($prioritykey>=$priority)
+ break;
+ else
+ $cc+=count($items);
+
+ if($index===false&&isset($this->_d[$priority])) {
+ $c=count($this->_d[$priority]);
+ $c+=$cc;
+ $this->_d[$priority][]=$item;
+ } else if(isset($this->_d[$priority])) {
+ $c=$index+$cc;
+ array_splice($this->_d[$priority],$index,0,array($item));
+ } else {
+ $c = $cc;
+ $this->_o = false;
+ $this->_d[$priority]=array($item);
+ }
+
+ if($this->_fd&&is_array($this->_fd)) // if there is a flattened array cache
+ array_splice($this->_fd,$c,0,array($item));
+ } else {
+ $c=null;
+ if($index===false&&isset($this->_d[$priority])) {
+ $cc=count($this->_d[$priority]);
+ $this->_d[$priority][]=$item;
+ } else if(isset($this->_d[$priority])) {
+ $cc=$index;
+ array_splice($this->_d[$priority],$index,0,array($item));
+ } else {
+ $cc=0;
+ $this->_o=false;
+ $this->_d[$priority]=array($item);
+ }
+ if($this->_fd&&is_array($this->_fd)&&count($this->_d)==1)
+ array_splice($this->_fd,$cc,0,array($item));
+ else
+ $this->_fd=null;
+ }
+
+ $this->_c++;
+
+ return $c;
+
+ }
+
+
+ /**
+ * Removes an item from the priority list.
+ * The list will search for the item. The first matching item found will be removed from the list.
+ * @param mixed item the item to be removed.
+ * @param numeric priority of item to remove. without this parameter it defaults to false.
+ * A value of false means any priority. null will be filled in with the default priority.
+ * @return integer index within the flattened list at which the item is being removed
+ * @throws TInvalidDataValueException If the item does not exist
+ */
+ public function remove($item,$priority=false)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if(($p=$this->priorityOf($item,true))!==false)
+ {
+ if($priority!==false) {
+ if($priority===null)
+ $priority=$this->getDefaultPriority();
+ $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
+
+ if($p[0]!=$priority)
+ throw new TInvalidDataValueException('list_item_inexistent');
+ }
+ $this->removeAtIndexInPriority($p[1],$p[0]);
+ return $p[2];
+ }
+ else
+ throw new TInvalidDataValueException('list_item_inexistent');
+ }
+
+ /**
+ * Removes an item at the specified index in the flattened list.
+ * @param integer index of the item to be removed.
+ * @return mixed the removed item.
+ * @throws TInvalidDataValueException If the index specified exceeds the bound
+ * @throws TInvalidOperationException if the list is read-only
+ */
+ public function removeAt($index)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if(($priority=$this->priorityAt($index, true))!==false)
+ return $this->removeAtIndexInPriority($priority[1],$priority[0]);
+ throw new TInvalidDataValueException('list_index_invalid',$index);
+ }
+
+ /**
+ * Removes the item at a specific index within a priority. Override
+ * and call this method to insert your own functionality.
+ * @param integer index of item to remove within the priority.
+ * @param numeric priority of the item to remove, defaults to null, or left blank, it is then set to the default priority
+ * @return mixed the removed item.
+ * @throws TInvalidDataValueException If the item does not exist
+ */
+ public function removeAtIndexInPriority($index, $priority=null)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if($priority===null)
+ $priority=$this->getDefaultPriority();
+ $priority=(string)round(TPropertyValue::ensureFloat($priority),$this->_p);
+
+ if(!isset($this->_d[$priority])||$index<0||$index>=count($this->_d[$priority]))
+ throw new TInvalidDataValueException('list_item_inexistent');
+
+ // $value is an array of elements removed, only one
+ $value=array_splice($this->_d[$priority],$index,1);
+ $value=$value[0];
+
+ if(!count($this->_d[$priority]))
+ unset($this->_d[$priority]);
+
+ $this->_c--;
+ $this->_fd=null;
+ return $value;
+ }
+
+ /**
+ * Removes all items in the priority list by calling removeAtIndexInPriority from the last item to the first.
+ */
+ public function clear()
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ $d=array_reverse($this->_d,true);
+ foreach($this->_d as $priority=>$items) {
+ for($index=count($items)-1;$index>=0;$index--)
+ $this->removeAtIndexInPriority($index,$priority);
+ unset($this->_d[$priority]);
+ }
+ }
+
+ /**
+ * @param mixed item
+ * @return boolean whether the list contains the item
+ */
+ public function contains($item)
+ {
+ return $this->indexOf($item)>=0;
+ }
+
+ /**
+ * @param mixed item
+ * @return integer the index of the item in the flattened list (0 based), -1 if not found.
+ */
+ public function indexOf($item)
+ {
+ if(($index=array_search($item,$this->flattenPriorities(),true))===false)
+ return -1;
+ else
+ return $index;
+ }
+
+ /**
+ * Returns the priority of a particular item
+ * @param mixed the item to look for within the list
+ * @param boolean withindex this specifies if the full positional data of the item within the list is returned.
+ * This defaults to false, if no parameter is provided, so only provides the priority number of the item by default.
+ * @return numeric|array the priority of the item in the list, false if not found.
+ * if withindex is true, an array is returned of [0 => $priority, 1 => $priorityIndex, 2 => flattenedIndex,
+ * 'priority' => $priority, 'index' => $priorityIndex, 'absindex' => flattenedIndex]
+ */
+ public function priorityOf($item,$withindex = false)
+ {
+ $this->sortPriorities();
+
+ $absindex = 0;
+ foreach($this->_d as $priority=>$items) {
+ if(($index=array_search($item,$items,true))!==false) {
+ $absindex+=$index;
+ return $withindex?array($priority,$index,$absindex,
+ 'priority'=>$priority,'index'=>$index,'absindex'=>$absindex):$priority;
+ } else
+ $absindex+=count($items);
+ }
+
+ return false;
+ }
+
+ /**
+ * Retutrns the priority of an item at a particular flattened index.
+ * @param integer index of the item within the list
+ * @param boolean withindex this specifies if the full positional data of the item within the list is returned.
+ * This defaults to false, if no parameter is provided, so only provides the priority number of the item by default.
+ * @return numeric|array the priority of the item in the list, false if not found.
+ * if withindex is true, an array is returned of [0 => $priority, 1 => $priorityIndex, 2 => flattenedIndex,
+ * 'priority' => $priority, 'index' => $priorityIndex, 'absindex' => flattenedIndex]
+ */
+ public function priorityAt($index,$withindex = false)
+ {
+ if($index<0||$index>=$this->getCount())
+ throw new TInvalidDataValueException('list_index_invalid',$index);
+
+ $absindex=$index;
+ $this->sortPriorities();
+ foreach($this->_d as $priority=>$items) {
+ if($index>=($c=count($items)))
+ $index-=$c;
+ else
+ return $withindex?array($priority,$index,$absindex,
+ 'priority'=>$priority,'index'=>$index,'absindex'=>$absindex):$priority;
+ }
+ return false;
+ }
+
+ /**
+ * This inserts an item before another item within the list. It uses the same priority as the
+ * found index item and places the new item before it.
+ * @param mixed indexitem the item to index
+ * @param mixed the item to add before indexitem
+ * @return integer where the item has been inserted in the flattened list
+ * @throws TInvalidDataValueException If the item does not exist
+ */
+ public function insertBefore($indexitem, $item)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if(($priority=$this->priorityOf($indexitem,true))===false)
+ throw new TInvalidDataValueException('list_item_inexistent');
+
+ $this->insertAtIndexInPriority($item,$priority[1],$priority[0]);
+
+ return $priority[2];
+ }
+
+ /**
+ * This inserts an item after another item within the list. It uses the same priority as the
+ * found index item and places the new item after it.
+ * @param mixed indexitem the item to index
+ * @param mixed the item to add after indexitem
+ * @return integer where the item has been inserted in the flattened list
+ * @throws TInvalidDataValueException If the item does not exist
+ */
+ public function insertAfter($indexitem, $item)
+ {
+ if($this->getReadOnly())
+ throw new TInvalidOperationException('list_readonly',get_class($this));
+
+ if(($priority=$this->priorityOf($indexitem,true))===false)
+ throw new TInvalidDataValueException('list_item_inexistent');
+
+ $this->insertAtIndexInPriority($item,$priority[1]+1,$priority[0]);
+
+ return $priority[2]+1;
+ }
+
+ /**
+ * @return array the priority list of items in array
+ */
+ public function toArray()
+ {
+ return $this->flattenPriorities();
+ }
+
+ /**
+ * @return array the array of priorities keys with values of arrays of items. The priorities are sorted so important priorities, lower numerics, are first.
+ */
+ public function toPriorityArray()
+ {
+ $this->sortPriorities();
+ return $this->_d;
+ }
+
+ /**
+ * Combines the map elements which have a priority below the parameter value
+ * @param numeric the cut-off priority. All items of priority less than this are returned.
+ * @param boolean whether or not the input cut-off priority is inclusive. Default: false, not inclusive.
+ * @return array the array of priorities keys with values of arrays of items that are below a specified priority.
+ * The priorities are sorted so important priorities, lower numerics, are first.
+ */
+ public function toArrayBelowPriority($priority,$inclusive=false)
+ {
+ $this->sortPriorities();
+ $items=array();
+ foreach($this->_d as $itemspriority=>$itemsatpriority)
+ {
+ if((!$inclusive&&$itemspriority>=$priority)||$itemspriority>$priority)
+ break;
+ $items=array_merge($items,$itemsatpriority);
+ }
+ return $items;
+ }
+
+ /**
+ * Combines the map elements which have a priority above the parameter value
+ * @param numeric the cut-off priority. All items of priority greater than this are returned.
+ * @param boolean whether or not the input cut-off priority is inclusive. Default: true, inclusive.
+ * @return array the array of priorities keys with values of arrays of items that are above a specified priority.
+ * The priorities are sorted so important priorities, lower numerics, are first.
+ */
+ public function toArrayAbovePriority($priority,$inclusive=true)
+ {
+ $this->sortPriorities();
+ $items=array();
+ foreach($this->_d as $itemspriority=>$itemsatpriority)
+ {
+ if((!$inclusive&&$itemspriority<=$priority)||$itemspriority<$priority)
+ continue;
+ $items=array_merge($items,$itemsatpriority);
+ }
+ return $items;
+ }
+
+
+ /**
+ * Copies iterable data into the priority list.
+ * Note, existing data in the map will be cleared first.
+ * @param mixed the data to be copied from, must be an array or object implementing Traversable
+ * @throws TInvalidDataTypeException If data is neither an array nor an iterator.
+ */
+ public function copyFrom($data)
+ {
+ if($data instanceof TPriorityList)
+ {
+ if($this->getCount()>0)
+ $this->clear();
+ foreach($data->getPriorities() as $priority)
+ {
+ foreach($data->itemsAtPriority($priority) as $index=>$item)
+ $this->insertAtIndexInPriority($item,$index,$priority);
+ }
+ } else if(is_array($data)||$data instanceof Traversable) {
+ if($this->getCount()>0)
+ $this->clear();
+ foreach($data as $key=>$item)
+ $this->add($item);
+ } else if($data!==null)
+ throw new TInvalidDataTypeException('map_data_not_iterable');
+ }
+
+ /**
+ * Merges iterable data into the priority list.
+ * New data will be appended to the end of the existing data. If another TPriorityList is merged,
+ * the incoming parameter items will be appended at the priorities they are present. These items will be added
+ * to the end of the existing items with equal priorities, if there are any.
+ * @param mixed the data to be merged with, must be an array or object implementing Traversable
+ * @throws TInvalidDataTypeException If data is neither an array nor an iterator.
+ */
+ public function mergeWith($data)
+ {
+ if($data instanceof TPriorityList)
+ {
+ foreach($data->getPriorities() as $priority)
+ {
+ foreach($data->itemsAtPriority($priority) as $index=>$item)
+ $this->insertAtIndexInPriority($item,false,$priority);
+ }
+ }
+ else if(is_array($data)||$data instanceof Traversable)
+ {
+ foreach($data as $priority=>$item)
+ $this->add($item);
+
+ }
+ else if($data!==null)
+ throw new TInvalidDataTypeException('map_data_not_iterable');
+ }
+
+ /**
+ * Returns whether there is an element at the specified offset.
+ * This method is required by the interface ArrayAccess.
+ * @param mixed the offset to check on
+ * @return boolean
+ */
+ public function offsetExists($offset)
+ {
+ return ($offset>=0&&$offset<$this->getCount());
+ }
+
+ /**
+ * Returns the element at the specified offset.
+ * This method is required by the interface ArrayAccess.
+ * @param integer the offset to retrieve element.
+ * @return mixed the element at the offset, null if no element is found at the offset
+ */
+ public function offsetGet($offset)
+ {
+ return $this->itemAt($offset);
+ }
+
+ /**
+ * Sets the element at the specified offset. This method is required by the interface ArrayAccess.
+ * Setting elements in a priority list is not straight forword when appending and setting at the
+ * end boundary. When appending without an offset (a null offset), the item will be added at
+ * the default priority. The item may not be the last item in the list. When appending with an
+ * offset equal to the count of the list, the item will get be appended with the last items priority.
+ *
+ * All together, when setting the location of an item, the item stays in that location, but appending
+ * an item into a priority list doesn't mean the item is at the end of the list.
+ * @param integer the offset to set element
+ * @param mixed the element value
+ */
+ public function offsetSet($offset,$item)
+ {
+ if($offset===null)
+ return $this->add($item);
+ if($offset===$this->getCount()) {
+ $priority=$this->priorityAt($offset-1,true);
+ $priority[1]++;
+ } else {
+ $priority=$this->priorityAt($offset,true);
+ $this->removeAtIndexInPriority($priority[1],$priority[0]);
+ }
+ $this->insertAtIndexInPriority($item,$priority[1],$priority[0]);
+ }
+
+ /**
+ * Unsets the element at the specified offset.
+ * This method is required by the interface ArrayAccess.
+ * @param mixed the offset to unset element
+ */
+ public function offsetUnset($offset)
+ {
+ $this->removeAt($offset);
+ }
+}