Prestashop : Override Product controller : array feature with id feature as key

ProductController.php

<?php

class ProductController extends ProductControllerCore
{

	public function initContent()
	{
		FrontController::initContent();

		if (!$this->errors)
		{
			if (Pack::isPack((int)$this->product->id) && !Pack::isInStock((int)$this->product->id))
				$this->product->quantity = 0;

			$this->product->description = $this->transformDescriptionWithImg($this->product->description);

			// Assign to the template the id of the virtual product. "0" if the product is not downloadable.
			$this->context->smarty->assign('virtual', ProductDownload::getIdFromIdProduct((int)$this->product->id));

			$this->context->smarty->assign('customizationFormTarget', Tools::safeOutput(urldecode($_SERVER['REQUEST_URI'])));

			if (Tools::isSubmit('submitCustomizedDatas'))
			{
				// If cart has not been saved, we need to do it so that customization fields can have an id_cart
				// We check that the cookie exists first to avoid ghost carts
				if (!$this->context->cart->id && isset($_COOKIE[$this->context->cookie->getName()]))
				{
					$this->context->cart->add();
					$this->context->cookie->id_cart = (int)$this->context->cart->id;
				}
				$this->pictureUpload();
				$this->textRecord();
				$this->formTargetFormat();
			}
			else if (Tools::getIsset('deletePicture') && !$this->context->cart->deleteCustomizationToProduct($this->product->id, Tools::getValue('deletePicture')))
				$this->errors[] = Tools::displayError('An error occurred while deleting the selected picture.');

			
			$pictures = array();
			$text_fields = array();
			if ($this->product->customizable)
			{
				$files = $this->context->cart->getProductCustomization($this->product->id, Product::CUSTOMIZE_FILE, true);
				foreach ($files as $file)
					$pictures['pictures_'.$this->product->id.'_'.$file['index']] = $file['value'];

				$texts = $this->context->cart->getProductCustomization($this->product->id, Product::CUSTOMIZE_TEXTFIELD, true);

				foreach ($texts as $text_field)
					$text_fields['textFields_'.$this->product->id.'_'.$text_field['index']] = str_replace('<br />', "\n", $text_field['value']);
			}

			$this->context->smarty->assign(array(
				'pictures' => $pictures,
				'textFields' => $text_fields));

			// Assign template vars related to the category + execute hooks related to the category
			$this->assignCategory();
			// Assign template vars related to the price and tax
			$this->assignPriceAndTax();

			// Assign template vars related to the images
			$this->assignImages();
			// Assign attribute groups to the template
			$this->assignAttributesGroups();

			// Assign attributes combinations to the template
			$this->assignAttributesCombinations();

			// Pack management
			$pack_items = $this->product->cache_is_pack ? Pack::getItemTable($this->product->id, $this->context->language->id, true) : array();
			$this->context->smarty->assign('packItems', $pack_items);
			$this->context->smarty->assign('packs', Pack::getPacksTable($this->product->id, $this->context->language->id, true, 1));

			if (isset($this->category->id) && $this->category->id)
				$return_link = Tools::safeOutput($this->context->link->getCategoryLink($this->category));
			else
				$return_link = 'javascript: history.back();';

      /* Feature array by id */
      $features = $this->product->getFrontFeatures($this->context->language->id);
      foreach ($features as $key=>$value) {
        $features_by_key[$value['id_feature']]['name'] = $value['name'];
        $features_by_key[$value['id_feature']]['value'] = $value['value']; 	
      } 

      
			$this->context->smarty->assign(array(
				'stock_management' => Configuration::get('PS_STOCK_MANAGEMENT'),
				'customizationFields' => ($this->product->customizable) ? $this->product->getCustomizationFields($this->context->language->id) : false,
				'accessories' => $this->product->getAccessories($this->context->language->id),
				'return_link' => $return_link,
				'product' => $this->product,
				'product_manufacturer' => $product_manufacturer,
				'token' => Tools::getToken(false),
				'features' => $features,
        'features_by_key' => $features_by_key,
				'attachments' => (($this->product->cache_has_attachments) ? $this->product->getAttachments($this->context->language->id) : array()),
				'allow_oosp' => $this->product->isAvailableWhenOutOfStock((int)$this->product->out_of_stock),
				'last_qties' =>  (int)Configuration::get('PS_LAST_QTIES'),
				'HOOK_EXTRA_LEFT' => Hook::exec('displayLeftColumnProduct'),
				'HOOK_EXTRA_RIGHT' => Hook::exec('displayRightColumnProduct'),
				'HOOK_PRODUCT_OOS' => Hook::exec('actionProductOutOfStock', array('product' => $this->product)),
				'HOOK_PRODUCT_ACTIONS' => Hook::exec('displayProductButtons', array('product' => $this->product)),
				'HOOK_PRODUCT_TAB' =>  Hook::exec('displayProductTab', array('product' => $this->product)),
				'HOOK_PRODUCT_TAB_CONTENT' =>  Hook::exec('displayProductTabContent', array('product' => $this->product)),
				'display_qties' => (int)Configuration::get('PS_DISPLAY_QTIES'),
				'display_ht' => !Tax::excludeTaxeOption(),
				'currencySign' => $this->context->currency->sign,
				'currencyRate' => $this->context->currency->conversion_rate,
				'currencyFormat' => $this->context->currency->format,
				'currencyBlank' => $this->context->currency->blank,
				'jqZoomEnabled' => Configuration::get('PS_DISPLAY_JQZOOM'),
				'ENT_NOQUOTES' => ENT_NOQUOTES,
				'outOfStockAllowed' => (int)Configuration::get('PS_ORDER_OUT_OF_STOCK')
			));
		}

		$this->context->smarty->assign('errors', $this->errors);
		$this->setTemplate(_PS_THEME_DIR_.'product.tpl');
	}

}