<?php

namespace ManaPHP\Mvc\View {



    use ManaPHP\Component;

    use ManaPHP\Mvc\View\Renderer\EngineInterface;

    use ManaPHP\Mvc\View\Renderer\Exception;



    class Renderer extends Component implements RendererInterface

    {

        /**

         * @var \ManaPHP\Mvc\View\Renderer\EngineInterface[]

         */

        protected $_resolvedEngines = [];



        /**

         * @var array

         */

        protected $_registeredEngines = [];



        public function __construct()

        {

            $this->_registeredEngines['.phtml'] = 'ManaPHP\Mvc\View\Renderer\Engine\Php';

            $this->_registeredEngines['.tpl'] = 'ManaPHP\Mvc\View\Renderer\Engine\Smarty';

            $this->_registeredEngines['.html'] = 'ManaPHP\Mvc\View\Renderer\Engine\Html';

        }



        /**

         * @param string $extension

         *

         * @return \ManaPHP\Mvc\View\Renderer\EngineInterface

         * @throws \ManaPHP\Mvc\View\Renderer\Exception

         */

        protected function _loadEngine($extension)

        {

            $arguments = [$this->_dependencyInjector];

            $engine = $this->_registeredEngines[$extension];

            if ($engine instanceof \Closure) {

                $engine = call_user_func_array($engine, $arguments);

            } elseif (is_string($engine)) {

                $engine = $this->_dependencyInjector->getShared($engine, $arguments);

            }



            if (!$engine instanceof EngineInterface) {

                throw new Exception('Invalid template engine: it is not implements \ManaPHP\Mvc\Renderer\EngineInterface');

            }



            return $engine;

        }



        /** @noinspection PhpDocMissingThrowsInspection */

        /**

         * Checks whether $template exists on registered extensions and render it

         *

         * @noinspection PhpDocMissingThrowsInspection

         *

         * @param string  $template

         * @param boolean $directOutput

         * @param array   $vars

         *

         * @return static

         * @throws \ManaPHP\Mvc\View\Renderer\Exception

         */

        public function render($template, $vars, $directOutput = true)

        {

            $notExists = true;

            $content = null;



            foreach ($this->_registeredEngines as $extension => $engine) {

                $file = $template . $extension;

                if (file_exists($file)) {

                    if (DIRECTORY_SEPARATOR === '\\') {

                        $realPath = str_replace('\\', '/', realpath($file));

                        if ($file !== $realPath) {

                            trigger_error("File name ($realPath) case mismatch for $file", E_USER_ERROR);

                        }

                    }



                    if (!isset($this->_resolvedEngines[$extension])) {

                        $this->_resolvedEngines[$extension] = $this->_loadEngine($extension);

                    }



                    $engine = $this->_resolvedEngines[$extension];



                    $eventArguments = ['file' => $file, 'vars' => $vars];

                    $this->fireEvent('renderer:beforeRenderView', $eventArguments);



                    if (isset($vars['view'])) {

                        throw new Exception('variable \'view\' is reserved for PHP renderer engine.');

                    }

                    $vars['view'] = $this->_dependencyInjector->has('view') ? $this->_dependencyInjector->getShared('view') : null;



                    if (isset($vars['renderer'])) {

                        throw new Exception('variable \'render\' is reserved for PHP renderer engine.');

                    }

                    $vars['renderer'] = $this;



                    if ($directOutput) {

                        $engine->render($file, $vars);

                        $content = null;

                    } else {

                        ob_start();

                        try {

                            $engine->render($file, $vars);

                        } catch (\Exception $e) {

                            ob_end_clean();



                            /** @noinspection ExceptionsAnnotatingAndHandlingInspection */

                            throw $e;

                        }



                        $content = ob_get_clean();

                    }



                    $notExists = false;

                    $this->fireEvent('renderer:afterRenderView', $eventArguments);

                    break;

                }

            }



            if ($notExists) {

                throw new Exception("View '$template' was not found in the views directory");

            }



            return $content;

        }



        /**

         * @param string $template

         *

         * @return bool

         */

        public function exists($template)

        {

            foreach ($this->_registeredEngines as $extension => $engine) {

                if (is_file($template . $extension)) {

                    return true;

                }

            }



            return false;

        }



        /**

         * Register template engines

         *

         *<code>

         *$renderer->registerEngines(array(

         *  ".phtml" => "ManaPHP\Mvc\View\Renderer\Engine\Php",

         *  ".html" => "ManaPHP\Mvc\View\Renderer\Engine\Html",

         *));

         *</code>

         *

         * @param array $engines

         *

         * @return static

         */

        public function registerEngines($engines)

        {

            $this->_registeredEngines = $engines;



            return $this;

        }



        /**

         * Returns the registered template engines

         *

         * @brief array \ManaPHP\Mvc\View::getRegisteredEngines()

         */

        public function getRegisteredEngines()

        {

            return $this->_registeredEngines;

        }

    }

}