<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Form;
/**
* Default implementation of {@link FormRendererEngineInterface}.
*
* @author Bernhard Schussek <bschussek@gmail.com>
*/
abstract class AbstractRendererEngine implements FormRendererEngineInterface
{
/**
* The variable in {@link FormView} used as cache key.
*/
public const CACHE_KEY_VAR = 'cache_key';
protected $defaultThemes;
protected $themes = [];
protected $useDefaultThemes = [];
protected $resources = [];
private $resourceHierarchyLevels = [];
/**
* Creates a new renderer engine.
*
* @param array $defaultThemes The default themes. The type of these
* themes is open to the implementation.
*/
public function __construct(array $defaultThemes = [])
{
$this->defaultThemes = $defaultThemes;
}
/**
* {@inheritdoc}
*/
public function setTheme(FormView $view, $themes, $useDefaultThemes = true)
{
$cacheKey = $view->vars[self::CACHE_KEY_VAR];
// Do not cast, as casting turns objects into arrays of properties
$this->themes[$cacheKey] = \is_array($themes) ? $themes : [$themes];
$this->useDefaultThemes[$cacheKey] = (bool) $useDefaultThemes;
// Unset instead of resetting to an empty array, in order to allow
// implementations (like TwigRendererEngine) to check whether $cacheKey
// is set at all.
unset($this->resources[$cacheKey], $this->resourceHierarchyLevels[$cacheKey]);
}
/**
* {@inheritdoc}
*/
public function getResourceForBlockName(FormView $view, $blockName)
{
$cacheKey = $view->vars[self::CACHE_KEY_VAR];
if (!isset($this->resources[$cacheKey][$blockName])) {
$this->loadResourceForBlockName($cacheKey, $view, $blockName);
}
return $this->resources[$cacheKey][$blockName];
}
/**
* {@inheritdoc}
*/
public function getResourceForBlockNameHierarchy(FormView $view, array $blockNameHierarchy, $hierarchyLevel)
{
$cacheKey = $view->vars[self::CACHE_KEY_VAR];
$blockName = $blockNameHierarchy[$hierarchyLevel];
if (!isset($this->resources[$cacheKey][$blockName])) {
$this->loadResourceForBlockNameHierarchy($cacheKey, $view, $blockNameHierarchy, $hierarchyLevel);
}
return $this->resources[$cacheKey][$blockName];
}
/**
* {@inheritdoc}
*/
public function getResourceHierarchyLevel(FormView $view, array $blockNameHierarchy, $hierarchyLevel)
{
$cacheKey = $view->vars[self::CACHE_KEY_VAR];
$blockName = $blockNameHierarchy[$hierarchyLevel];
if (!isset($this->resources[$cacheKey][$blockName])) {
$this->loadResourceForBlockNameHierarchy($cacheKey, $view, $blockNameHierarchy, $hierarchyLevel);
}
// If $block was previously rendered loaded with loadTemplateForBlock(), the template
// is cached but the hierarchy level is not. In this case, we know that the block
// exists at this very hierarchy level, so we can just set it.
if (!isset($this->resourceHierarchyLevels[$cacheKey][$blockName])) {
$this->resourceHierarchyLevels[$cacheKey][$blockName] = $hierarchyLevel;
}
return $this->resourceHierarchyLevels[$cacheKey][$blockName];
}
/**
* Loads the cache with the resource for a given block name.
*
* @see getResourceForBlock()
*
* @param string $cacheKey The cache key of the form view
* @param FormView $view The form view for finding the applying themes
* @param string $blockName The name of the block to load
*
* @return bool True if the resource could be loaded, false otherwise
*/
abstract protected function loadResourceForBlockName($cacheKey, FormView $view, $blockName);
/**
* Loads the cache with the resource for a specific level of a block hierarchy.
*
* @see getResourceForBlockHierarchy()
*/
private function loadResourceForBlockNameHierarchy(string $cacheKey, FormView $view, array $blockNameHierarchy, $hierarchyLevel): bool
{
$blockName = $blockNameHierarchy[$hierarchyLevel];
// Try to find a template for that block
if ($this->loadResourceForBlockName($cacheKey, $view, $blockName)) {
// If loadTemplateForBlock() returns true, it was able to populate the
// cache. The only missing thing is to set the hierarchy level at which
// the template was found.
$this->resourceHierarchyLevels[$cacheKey][$blockName] = $hierarchyLevel;
return true;
}
if ($hierarchyLevel > 0) {
$parentLevel = $hierarchyLevel - 1;
$parentBlockName = $blockNameHierarchy[$parentLevel];
// The next two if statements contain slightly duplicated code. This is by intention
// and tries to avoid execution of unnecessary checks in order to increase performance.
if (isset($this->resources[$cacheKey][$parentBlockName])) {
// It may happen that the parent block is already loaded, but its level is not.
// In this case, the parent block must have been loaded by loadResourceForBlock(),
// which does not check the hierarchy of the block. Subsequently the block must have
// been found directly on the parent level.
if (!isset($this->resourceHierarchyLevels[$cacheKey][$parentBlockName])) {
$this->resourceHierarchyLevels[$cacheKey][$parentBlockName] = $parentLevel;
}
// Cache the shortcuts for further accesses
$this->resources[$cacheKey][$blockName] = $this->resources[$cacheKey][$parentBlockName];
$this->resourceHierarchyLevels[$cacheKey][$blockName] = $this->resourceHierarchyLevels[$cacheKey][$parentBlockName];
return true;
}
if ($this->loadResourceForBlockNameHierarchy($cacheKey, $view, $blockNameHierarchy, $parentLevel)) {
// Cache the shortcuts for further accesses
$this->resources[$cacheKey][$blockName] = $this->resources[$cacheKey][$parentBlockName];
$this->resourceHierarchyLevels[$cacheKey][$blockName] = $this->resourceHierarchyLevels[$cacheKey][$parentBlockName];
return true;
}
}
// Cache the result for further accesses
$this->resources[$cacheKey][$blockName] = false;
$this->resourceHierarchyLevels[$cacheKey][$blockName] = false;
return false;
}
}