vendor/symfony/form/Symfony/Component/Form/AbstractRendererEngine.php

   1 <?php
   2
   3 /*
   4  * This file is part of the Symfony package.
   5  *
   6  * (c) Fabien Potencier <fabien@symfony.com>
   7  *
   8  * For the full copyright and license information, please view the LICENSE
   9  * file that was distributed with this source code.
  10  */
  11
  12 namespace Symfony\Component\Form;
  13
  14 /**
  15  * Default implementation of {@link FormRendererEngineInterface}.
  16  *
  17  * @author Bernhard Schussek <bschussek@gmail.com>
  18  */
  19 abstract class AbstractRendererEngine implements FormRendererEngineInterface
  20 {
  21     /**
  22      * The variable in {@link FormView} used as cache key.
  23      */
  24     const CACHE_KEY_VAR = 'cache_key';
  25
  26     /**
  27      * @var array
  28      */
  29     protected $defaultThemes;
  30
  31     /**
  32      * @var array
  33      */
  34     protected $themes = array();
  35
  36     /**
  37      * @var array
  38      */
  39     protected $resources = array();
  40
  41     /**
  42      * @var array
  43      */
  44     private $resourceHierarchyLevels = array();
  45
  46     /**
  47      * Creates a new renderer engine.
  48      *
  49      * @param array $defaultThemes The default themes. The type of these
  50      *                             themes is open to the implementation.
  51      */
  52     public function __construct(array $defaultThemes = array())
  53     {
  54         $this->defaultThemes = $defaultThemes;
  55     }
  56
  57     /**
  58      * {@inheritdoc}
  59      */
  60     public function setTheme(FormView $view, $themes)
  61     {
  62         $cacheKey = $view->vars[self::CACHE_KEY_VAR];
  63
  64         // Do not cast, as casting turns objects into arrays of properties
  65         $this->themes[$cacheKey] = is_array($themes) ? $themes : array($themes);
  66
  67         // Unset instead of resetting to an empty array, in order to allow
  68         // implementations (like TwigRendererEngine) to check whether $cacheKey
  69         // is set at all.
  70         unset($this->resources[$cacheKey]);
  71         unset($this->resourceHierarchyLevels[$cacheKey]);
  72     }
  73
  74     /**
  75      * {@inheritdoc}
  76      */
  77     public function getResourceForBlockName(FormView $view, $blockName)
  78     {
  79         $cacheKey = $view->vars[self::CACHE_KEY_VAR];
  80
  81         if (!isset($this->resources[$cacheKey][$blockName])) {
  82             $this->loadResourceForBlockName($cacheKey, $view, $blockName);
  83         }
  84
  85         return $this->resources[$cacheKey][$blockName];
  86     }
  87
  88     /**
  89      * {@inheritdoc}
  90      */
  91     public function getResourceForBlockNameHierarchy(FormView $view, array $blockNameHierarchy, $hierarchyLevel)
  92     {
  93         $cacheKey = $view->vars[self::CACHE_KEY_VAR];
  94         $blockName = $blockNameHierarchy[$hierarchyLevel];
  95
  96         if (!isset($this->resources[$cacheKey][$blockName])) {
  97             $this->loadResourceForBlockNameHierarchy($cacheKey, $view, $blockNameHierarchy, $hierarchyLevel);
  98         }
  99
 100         return $this->resources[$cacheKey][$blockName];
 101     }
 102
 103     /**
 104      * {@inheritdoc}
 105      */
 106     public function getResourceHierarchyLevel(FormView $view, array $blockNameHierarchy, $hierarchyLevel)
 107     {
 108         $cacheKey = $view->vars[self::CACHE_KEY_VAR];
 109         $blockName = $blockNameHierarchy[$hierarchyLevel];
 110
 111         if (!isset($this->resources[$cacheKey][$blockName])) {
 112             $this->loadResourceForBlockNameHierarchy($cacheKey, $view, $blockNameHierarchy, $hierarchyLevel);
 113         }
 114
 115         // If $block was previously rendered loaded with loadTemplateForBlock(), the template
 116         // is cached but the hierarchy level is not. In this case, we know that the  block
 117         // exists at this very hierarchy level, so we can just set it.
 118         if (!isset($this->resourceHierarchyLevels[$cacheKey][$blockName])) {
 119             $this->resourceHierarchyLevels[$cacheKey][$blockName] = $hierarchyLevel;
 120         }
 121
 122         return $this->resourceHierarchyLevels[$cacheKey][$blockName];
 123     }
 124
 125     /**
 126      * Loads the cache with the resource for a given block name.
 127      *
 128      * @see getResourceForBlock()
 129      *
 130      * @param string   $cacheKey  The cache key of the form view.
 131      * @param FormView $view      The form view for finding the applying themes.
 132      * @param string   $blockName The name of the block to load.
 133      *
 134      * @return Boolean True if the resource could be loaded, false otherwise.
 135      */
 136     abstract protected function loadResourceForBlockName($cacheKey, FormView $view, $blockName);
 137
 138     /**
 139      * Loads the cache with the resource for a specific level of a block hierarchy.
 140      *
 141      * @see getResourceForBlockHierarchy()
 142      *
 143      * @param string   $cacheKey           The cache key used for storing the
 144      *                                     resource.
 145      * @param FormView $view               The form view for finding the applying
 146      *                                     themes.
 147      * @param array    $blockNameHierarchy The block hierarchy, with the most
 148      *                                     specific block name at the end.
 149      * @param integer  $hierarchyLevel     The level in the block hierarchy that
 150      *                                     should be loaded.
 151      *
 152      * @return Boolean True if the resource could be loaded, false otherwise.
 153      */
 154     private function loadResourceForBlockNameHierarchy($cacheKey, FormView $view, array $blockNameHierarchy, $hierarchyLevel)
 155     {
 156         $blockName = $blockNameHierarchy[$hierarchyLevel];
 157
 158         // Try to find a template for that block
 159         if ($this->loadResourceForBlockName($cacheKey, $view, $blockName)) {
 160             // If loadTemplateForBlock() returns true, it was able to populate the
 161             // cache. The only missing thing is to set the hierarchy level at which
 162             // the template was found.
 163             $this->resourceHierarchyLevels[$cacheKey][$blockName] = $hierarchyLevel;
 164
 165             return true;
 166         }
 167
 168         if ($hierarchyLevel > 0) {
 169             $parentLevel = $hierarchyLevel - 1;
 170             $parentBlockName = $blockNameHierarchy[$parentLevel];
 171
 172             // The next two if statements contain slightly duplicated code. This is by intention
 173             // and tries to avoid execution of unnecessary checks in order to increase performance.
 174
 175             if (isset($this->resources[$cacheKey][$parentBlockName])) {
 176                 // It may happen that the parent block is already loaded, but its level is not.
 177                 // In this case, the parent block must have been loaded by loadResourceForBlock(),
 178                 // which does not check the hierarchy of the block. Subsequently the block must have
 179                 // been found directly on the parent level.
 180                 if (!isset($this->resourceHierarchyLevels[$cacheKey][$parentBlockName])) {
 181                     $this->resourceHierarchyLevels[$cacheKey][$parentBlockName] = $parentLevel;
 182                 }
 183
 184                 // Cache the shortcuts for further accesses
 185                 $this->resources[$cacheKey][$blockName] = $this->resources[$cacheKey][$parentBlockName];
 186                 $this->resourceHierarchyLevels[$cacheKey][$blockName] = $this->resourceHierarchyLevels[$cacheKey][$parentBlockName];
 187
 188                 return true;
 189             }
 190
 191             if ($this->loadResourceForBlockNameHierarchy($cacheKey, $view, $blockNameHierarchy, $parentLevel)) {
 192                 // Cache the shortcuts for further accesses
 193                 $this->resources[$cacheKey][$blockName] = $this->resources[$cacheKey][$parentBlockName];
 194                 $this->resourceHierarchyLevels[$cacheKey][$blockName] = $this->resourceHierarchyLevels[$cacheKey][$parentBlockName];
 195
 196                 return true;
 197             }
 198         }
 199
 200         // Cache the result for further accesses
 201         $this->resources[$cacheKey][$blockName] = false;
 202         $this->resourceHierarchyLevels[$cacheKey][$blockName] = false;
 203
 204         return false;
 205     }
 206 }