<?php

namespace Delicious;

/**
 * This class provides the template rendering functions.
 *
 * @author Michael
 * @copyright (c) 2013, Michael Beers | Online Media en Design
 * @link http://michaelbeers.nl
 * @since 1.0
 */
class View {

    private $_module = '';
    private $_controller = '';
    private $_action = '';
    private $_theme = null; // The theme name.
    private $_layout = false; // The layout where the body should be wrapped in.
    private $_title = '';
    private $_titleSeparator = ' - ';
    private $_metadata = array();
    private $_scripts = array();
    private $_partials = array();
    private $_breadcrumbs = array();
    private $_cacheLifetime = 0;
    private $_data = array();
    private $_output = null;

    /**
     * Constructor.
     */
    public function __construct(array $config) {
        $this->_titleSeparator = $config['title_separator'];
        $this->_theme = $config['theme'];
        $this->_cacheLifetime = $config['cache_lifetime'];

        // Setup module, controller and action.
        $mc = explode("\\Controller\\", Dispatch::$_controller);
        $this->_module = $mc[0];
        $this->_controller = $mc[1];
        $this->_action = Dispatch::$_action;
    }

    /**
     * Magic get function for getting view data.
     *
     * @param string $name
     * @return mixed
     */
    public function __get($name) {
        return $this->_data[$name];
    }

    /**
     * Magic set function for setting view data.
     *
     * @param string $name
     * @param mixed $value
     */
    public function __set($name, $value) {
        $this->_data[$name] = $value;
    }

    /**
     * Magic function for rendering the view data.
     */
    public function __toString() {
        $view = strtolower($this->_controller) . '-' . strtolower($this->_action);
        return $this->render($view, array(), true);
    }

    // ----------------------------------------------------------------------

    /**
     * Render the HTML output.
     *
     * @param string $view
     * @param array $data
     * @param boolean $return
     */
    public function render($view, array $data = array(), $return = false) {
        // Merge all the given data to use it in all view files.
        is_array($data) || $data = (array) $data;
        $this->_data = array_merge($this->_data, $data);

        // Check if the data is cached or not.
        if ($this->_cacheLifetime > 0 && $this->_inCache($view)) {
            // The template is cached so it will loaded from the cache.
            $this->_output = $this->_loadCachedView($view);
        } else {
            // The template is not cached so it will be loaded by searching.
            if (empty($this->_title)) {
                // Guess the title whether its empty.
                $this->_title = $this->_guessTitle();
            }

            // Setup the default template variable.
            $template = array();
            $template['title'] = $this->_title;
            $template['breadcrumbs'] = $this->_breadcrumbs;
            $template['metadata'] = implode("\n\t\t", $this->_metadata) . "\n";
            $template['scripts'] = implode("\n\t\t", $this->_scripts) . "\n";
            $template['partials'] = array();

            $this->_data['template'] = &$template; // Make an reference for later updates.
            // Load all partial data.
            foreach ($this->_partials as $name => $partial) {
                // Fix data array.
                is_array($partial['data']) || $partial['data'] = (array) $partial['data'];

                if (isset($partial['view'])) {
                    $template['partials'][$name] = $this->_loadView($partial['view'], $partial['data']);
                } else {
                    $template['partials'][$name] = $partial['string'];
                }
            }

            // Load basic view.
            $this->_output = $this->_loadView($view, array());

            // Wrap the output into a template file.
            // Cache the view?
            if ($this->_cacheLifetime > 0) {
                $this->_setCache($view, $this->_output);
            }
        }

        // Return or print the output.
        if (!$return) {
            print $this->_output;
            return;
        }

        return $this->_output;
    }

    // ----------------------------------------------------------------------

    /**
     * Set the page title.
     *
     * @param string Each parameter will be a segment.
     */
    public function setTitle() {
        if ($segments = func_get_args()) {
            $this->_title = implode($this->_titleSeparator, $segments);
        } else {
            $this->_title = $this->_guessTitle();
        }
    }

    /**
     * Guess the title based on the module, controller and action.
     *
     * @return string
     */
    private function _guessTitle() {
        $title_parts = array();

        // Check whether the action isn't the default index.
        if ($this->_action != 'index') {
            $title_parts[] = $this->_action;
        }

        // Make sure the controller name does not exists as title part.
        if (!in_array($this->_controller, $title_parts)) {
            $title_parts[] = $this->_controller;
        }

        // Make sure the module name does not exists as title part.
        if (!in_array($this->_module, $title_parts)) {
            $title_parts[] = $this->_module;
        }

        $title = humanize(implode($this->_titleSeparator, $title_parts));
        return $title;
    }

    // ----------------------------------------------------------------------

    /**
     * Add new breadcrumb to the page.
     *
     * @param type $name
     * @param type $url
     */
    public function addBreadcrumb($name, $url = '') {
        $this->_breadcrumbs[] = array('name' => $name, 'url' => $url);
    }

    /**
     * Add new metadata to the page.
     *
     * @param string $name Name of the metadata.
     * @param string $content Content of the metadata.
     * @param string $type Metadata type (meta, link or charset).
     */
    public function addMeta($name, $content, $type = 'meta') {
        $name = h(strip_tags($name));
        $content = h(strip_tags($content));

        // Fix for keywords.
        if ($name === 'keywords' && !strpos($content, ', ')) {
            $content = preg_replace('/[\s]+/', ', ', trim($content));
        }

        // Fix for html5 charset
        if ($name === 'charset') {
            $type = 'charset';
        }

        switch ($type) {
            case 'meta':
                $this->_metadata[$name] = '<meta name="' . $name . '" content="' . $content .
                        '" />';
                break;
            case 'link':
                $this->_metadata[$content] = '<link rel="' . $name . '" href="' . $content .
                        '" />';
                break;
            case 'charset':
                $this->_metadata[$name] = '<meta charset="' . $content . '" />';
                break;
        }
    }

    /**
     * Add new script to the page.
     *
     * @param string $name Name of the script.
     * @param string $url Url of the script.
     */
    public function addScript($name, $url, $type = 'text/javascript') {
        $this->_scripts[$name] = '<script type="' . $type . '" src="' . $url . '"></script>';
    }

    // ----------------------------------------------------------------------

    /**
     * Return cache id.
     *
     * @param string $view
     * @return string
     */
    private function _getCacheId($view) {
        $parts = array(
            strtolower($this->_module),
            strtolower($this->_controller),
            strtolower($this->_action),
            $view
        );

        return md5(implode('-', $parts));
    }

    /**
     * Return whether the view is already in the cache or not.
     *
     * @param string $view
     * @return boolean
     */
    private function _inCache($view) {
        $id = $this->_getCacheId($view);
        $filename = PUBLIC_PATH . 'data' . DS . 'cache' . DS . $id . '.cache';

        if (is_file($filename)) {
            clearstatcache();

            if (filemtime($filename) > (time() - $this->_cacheLifetime)) {
                $isCached = true;
            }
        }

        return isset($isCached) ? true : false;
    }

    /**
     * Sets a file to the cache.
     *
     * @param string $view
     * @param mixed $content
     */
    private function _setCache($view, $content) {
        $id = $this->_getCacheId($view);
        $filename = PUBLIC_PATH . 'data' . DS . 'cache' . DS . $id . '.cache';
        $directory = PUBLIC_PATH . 'data' . DS . 'cache' . DS;

        // Make directory if not exists.
        @mkdir($directory, 0775);

        // Write the content to the cache.
        if ($fp = fopen($filename, 'wb')) {
            fwrite($fp, $content);
            fclose($fp);
        }
    }

    /**
     * Return a cached view.
     *
     * @param string $view
     * @return mixed
     */
    private function _loadCachedView($view) {
        $id = $this->_getCacheId($view);
        $filename = PUBLIC_PATH . 'data' . DS . 'cache' . DS . $id . '.cache';

        if ($fp = fopen($filename, 'rb')) {
            $output = fread($fp, filesize($filename));
            fclose($fp);
        }

        return isset($output) ? $output : false;
    }

    /**
     * Return a normal view.
     *
     * @param string $view
     * @param array $data
     * @param string $override_path
     * @return mixed
     */
    private function _loadView($view, array $data = array(), $override_path = false) {
        $path = PACKAGE_PATH . ucfirst($this->_module) . DS . 'View' . DS . $view . EXT;

        // Override the default path.
        if ($override_path) {
            $path = $override_path . $view . EXT;
        }

        // Check if the file exists.
        if (!file_exists($path)) {
            $output = 'Error loading view "' . $view . '" in "' . ucfirst($this->_module) . DS . 'View' . '".';
            log_message($output);
            return $output;
        }

        // Start rendering (gzip compression supported)
        if (ob_start("ob_gzhandler") === false) {
            ob_start();
        }

        extract($this->_data);
        require ($path);
        $output = ob_get_clean();
        // End rendering...

        return $output;
    }

}