353 lines
10 KiB
PHP
353 lines
10 KiB
PHP
<?php
|
|
|
|
namespace SilverStripe\View;
|
|
|
|
use ArrayIterator;
|
|
use Iterator;
|
|
|
|
/**
|
|
* This tracks the current scope for an SSViewer instance. It has three goals:
|
|
* - Handle entering & leaving sub-scopes in loops and withs
|
|
* - Track Up and Top
|
|
* - (As a side effect) Inject data that needs to be available globally (used to live in ViewableData)
|
|
*
|
|
* In order to handle up, rather than tracking it using a tree, which would involve constructing new objects
|
|
* for each step, we use indexes into the itemStack (which already has to exist).
|
|
*
|
|
* Each item has three indexes associated with it
|
|
*
|
|
* - Pop. Which item should become the scope once the current scope is popped out of
|
|
* - Up. Which item is up from this item
|
|
* - Current. Which item is the first time this object has appeared in the stack
|
|
*
|
|
* We also keep the index of the current starting point for lookups. A lookup is a sequence of obj calls -
|
|
* when in a loop or with tag the end result becomes the new scope, but for injections, we throw away the lookup
|
|
* and revert back to the original scope once we've got the value we're after
|
|
*/
|
|
class SSViewer_Scope
|
|
{
|
|
const ITEM = 0;
|
|
const ITEM_ITERATOR = 1;
|
|
const ITEM_ITERATOR_TOTAL = 2;
|
|
const POP_INDEX = 3;
|
|
const UP_INDEX = 4;
|
|
const CURRENT_INDEX = 5;
|
|
const ITEM_OVERLAY = 6;
|
|
|
|
/**
|
|
* The stack of previous items ("scopes") - an indexed array of: item, item iterator, item iterator total,
|
|
* pop index, up index, current index & parent overlay
|
|
*
|
|
* @var array
|
|
*/
|
|
private $itemStack = [];
|
|
|
|
/**
|
|
* The current "global" item (the one any lookup starts from)
|
|
*
|
|
* @var object
|
|
*/
|
|
protected $item;
|
|
|
|
/**
|
|
* If we're looping over the current "global" item, here's the iterator that tracks with item we're up to
|
|
*
|
|
* @var Iterator
|
|
*/
|
|
protected $itemIterator;
|
|
|
|
/**
|
|
* Total number of items in the iterator
|
|
*
|
|
* @var int
|
|
*/
|
|
protected $itemIteratorTotal;
|
|
|
|
/**
|
|
* A pointer into the item stack for the item that will become the active scope on the next pop call
|
|
*
|
|
* @var int
|
|
*/
|
|
private $popIndex;
|
|
|
|
/**
|
|
* A pointer into the item stack for which item is "up" from this one
|
|
*
|
|
* @var int
|
|
*/
|
|
private $upIndex;
|
|
|
|
/**
|
|
* A pointer into the item stack for which the active item (or null if not in stack yet)
|
|
*
|
|
* @var int
|
|
*/
|
|
private $currentIndex;
|
|
|
|
/**
|
|
* A store of copies of the main item stack, so it's preserved during a lookup from local scope
|
|
* (which may push/pop items to/from the main item stack)
|
|
*
|
|
* @var array
|
|
*/
|
|
private $localStack = [];
|
|
|
|
/**
|
|
* The index of the current item in the main item stack, so we know where to restore the scope
|
|
* stored in $localStack.
|
|
*
|
|
* @var int
|
|
*/
|
|
private $localIndex = 0;
|
|
|
|
/**
|
|
* @var object $item
|
|
* @var SSViewer_Scope $inheritedScope
|
|
*/
|
|
public function __construct($item, SSViewer_Scope $inheritedScope = null)
|
|
{
|
|
$this->item = $item;
|
|
|
|
$this->itemIterator = ($inheritedScope) ? $inheritedScope->itemIterator : null;
|
|
$this->itemIteratorTotal = ($inheritedScope) ? $inheritedScope->itemIteratorTotal : 0;
|
|
$this->itemStack[] = [$this->item, $this->itemIterator, $this->itemIteratorTotal, null, null, 0];
|
|
}
|
|
|
|
/**
|
|
* Returns the current "active" item
|
|
*
|
|
* @return object
|
|
*/
|
|
public function getItem()
|
|
{
|
|
return $this->itemIterator ? $this->itemIterator->current() : $this->item;
|
|
}
|
|
|
|
/**
|
|
* Called at the start of every lookup chain by SSTemplateParser to indicate a new lookup from local scope
|
|
*
|
|
* @return self
|
|
*/
|
|
public function locally()
|
|
{
|
|
list(
|
|
$this->item,
|
|
$this->itemIterator,
|
|
$this->itemIteratorTotal,
|
|
$this->popIndex,
|
|
$this->upIndex,
|
|
$this->currentIndex
|
|
) = $this->itemStack[$this->localIndex];
|
|
|
|
// Remember any un-completed (resetLocalScope hasn't been called) lookup chain. Even if there isn't an
|
|
// un-completed chain we need to store an empty item, as resetLocalScope doesn't know the difference later
|
|
$this->localStack[] = array_splice($this->itemStack, $this->localIndex + 1);
|
|
|
|
return $this;
|
|
}
|
|
|
|
/**
|
|
* Reset the local scope - restores saved state to the "global" item stack. Typically called after
|
|
* a lookup chain has been completed
|
|
*/
|
|
public function resetLocalScope()
|
|
{
|
|
// Restore previous un-completed lookup chain if set
|
|
$previousLocalState = $this->localStack ? array_pop($this->localStack) : null;
|
|
array_splice($this->itemStack, $this->localIndex + 1, count($this->itemStack ?? []), $previousLocalState);
|
|
|
|
list(
|
|
$this->item,
|
|
$this->itemIterator,
|
|
$this->itemIteratorTotal,
|
|
$this->popIndex,
|
|
$this->upIndex,
|
|
$this->currentIndex
|
|
) = end($this->itemStack);
|
|
}
|
|
|
|
/**
|
|
* @param string $name
|
|
* @param array $arguments
|
|
* @param bool $cache
|
|
* @param string $cacheName
|
|
* @return mixed
|
|
*/
|
|
public function getObj($name, $arguments = [], $cache = false, $cacheName = null)
|
|
{
|
|
$on = $this->itemIterator ? $this->itemIterator->current() : $this->item;
|
|
return $on->obj($name, $arguments, $cache, $cacheName);
|
|
}
|
|
|
|
/**
|
|
* @param string $name
|
|
* @param array $arguments
|
|
* @param bool $cache
|
|
* @param string $cacheName
|
|
* @return $this
|
|
*/
|
|
public function obj($name, $arguments = [], $cache = false, $cacheName = null)
|
|
{
|
|
switch ($name) {
|
|
case 'Up':
|
|
if ($this->upIndex === null) {
|
|
throw new \LogicException('Up called when we\'re already at the top of the scope');
|
|
}
|
|
|
|
list(
|
|
$this->item,
|
|
$this->itemIterator,
|
|
$this->itemIteratorTotal,
|
|
/* dud */,
|
|
$this->upIndex,
|
|
$this->currentIndex
|
|
) = $this->itemStack[$this->upIndex];
|
|
break;
|
|
case 'Top':
|
|
list(
|
|
$this->item,
|
|
$this->itemIterator,
|
|
$this->itemIteratorTotal,
|
|
/* dud */,
|
|
$this->upIndex,
|
|
$this->currentIndex
|
|
) = $this->itemStack[0];
|
|
break;
|
|
default:
|
|
$this->item = $this->getObj($name, $arguments, $cache, $cacheName);
|
|
$this->itemIterator = null;
|
|
$this->upIndex = $this->currentIndex ? $this->currentIndex : count($this->itemStack) - 1;
|
|
$this->currentIndex = count($this->itemStack);
|
|
break;
|
|
}
|
|
|
|
$this->itemStack[] = [
|
|
$this->item,
|
|
$this->itemIterator,
|
|
$this->itemIteratorTotal,
|
|
null,
|
|
$this->upIndex,
|
|
$this->currentIndex
|
|
];
|
|
return $this;
|
|
}
|
|
|
|
/**
|
|
* Gets the current object and resets the scope.
|
|
*
|
|
* @return object
|
|
*/
|
|
public function self()
|
|
{
|
|
$result = $this->itemIterator ? $this->itemIterator->current() : $this->item;
|
|
$this->resetLocalScope();
|
|
|
|
return $result;
|
|
}
|
|
|
|
/**
|
|
* Jump to the last item in the stack, called when a new item is added before a loop/with
|
|
*
|
|
* @return self
|
|
*/
|
|
public function pushScope()
|
|
{
|
|
$newLocalIndex = count($this->itemStack ?? []) - 1;
|
|
|
|
$this->popIndex = $this->itemStack[$newLocalIndex][SSViewer_Scope::POP_INDEX] = $this->localIndex;
|
|
$this->localIndex = $newLocalIndex;
|
|
|
|
// We normally keep any previous itemIterator around, so local $Up calls reference the right element. But
|
|
// once we enter a new global scope, we need to make sure we use a new one
|
|
$this->itemIterator = $this->itemStack[$newLocalIndex][SSViewer_Scope::ITEM_ITERATOR] = null;
|
|
|
|
return $this;
|
|
}
|
|
|
|
/**
|
|
* Jump back to "previous" item in the stack, called after a loop/with block
|
|
*
|
|
* @return self
|
|
*/
|
|
public function popScope()
|
|
{
|
|
$this->localIndex = $this->popIndex;
|
|
$this->resetLocalScope();
|
|
|
|
return $this;
|
|
}
|
|
|
|
/**
|
|
* Fast-forwards the current iterator to the next item
|
|
*
|
|
* @return mixed
|
|
*/
|
|
public function next()
|
|
{
|
|
if (!$this->item) {
|
|
return false;
|
|
}
|
|
|
|
if (!$this->itemIterator) {
|
|
if (is_array($this->item)) {
|
|
$this->itemIterator = new ArrayIterator($this->item);
|
|
} else {
|
|
$this->itemIterator = $this->item->getIterator();
|
|
}
|
|
|
|
$this->itemStack[$this->localIndex][SSViewer_Scope::ITEM_ITERATOR] = $this->itemIterator;
|
|
$this->itemIteratorTotal = iterator_count($this->itemIterator); // Count the total number of items
|
|
$this->itemStack[$this->localIndex][SSViewer_Scope::ITEM_ITERATOR_TOTAL] = $this->itemIteratorTotal;
|
|
$this->itemIterator->rewind();
|
|
} else {
|
|
$this->itemIterator->next();
|
|
}
|
|
|
|
$this->resetLocalScope();
|
|
|
|
if (!$this->itemIterator->valid()) {
|
|
return false;
|
|
}
|
|
|
|
return $this->itemIterator->key();
|
|
}
|
|
|
|
/**
|
|
* @param string $name
|
|
* @param array $arguments
|
|
* @return mixed
|
|
*/
|
|
public function __call($name, $arguments)
|
|
{
|
|
$on = $this->itemIterator ? $this->itemIterator->current() : $this->item;
|
|
$retval = $on ? $on->$name(...$arguments) : null;
|
|
|
|
$this->resetLocalScope();
|
|
return $retval;
|
|
}
|
|
|
|
/**
|
|
* @return array
|
|
*/
|
|
protected function getItemStack()
|
|
{
|
|
return $this->itemStack;
|
|
}
|
|
|
|
/**
|
|
* @param array $stack
|
|
*/
|
|
protected function setItemStack(array $stack)
|
|
{
|
|
$this->itemStack = $stack;
|
|
}
|
|
|
|
/**
|
|
* @return int|null
|
|
*/
|
|
protected function getUpIndex()
|
|
{
|
|
return $this->upIndex;
|
|
}
|
|
}
|