<?php

namespace Anax\View;

/**
 * A view container, store all views per region, render at will.
 */
class ViewContainer implements
    \Anax\Common\ConfigureInterface,
    \Anax\Common\AppInjectableInterface
{
    use \Anax\Common\ConfigureTrait,
        \Anax\Common\AppInjectableTrait;


    /** @var [] $views Array for all views. */
    private $views = [];


    /**
     * Convert template to path to template file.
     *
     * @param string $template the name of the template file to include
     *
     * @throws Anax\View\Exception when template file is missing
     *
     * @return string as path to the template file
     */
    public function getTemplateFile($template)
    {
        $paths  = $this->config["path"];
        $suffix = $this->config["suffix"];

        foreach ($paths as $path) {
            $file = $path . "/" . $template . $suffix;
            if (is_file($file)) {
                return $file;
            }
        }

        throw new Exception("Could not find template file '$template'.");
    }


    /**
     * Add (create) a view to be included, pass optional data and put the
     * view in an optional specific region (default region is "main") and
     * pass an optional sort value where the highest value is rendered first.
     * The $template can be a:
     *  filename (string),
     *  callback (array with key callback set to a callable array),
     *  view array (key value array with template, data, region, sort)
     *
     * @param string  $template the name of the template file to include.
     * @param array   $data     variables to make available to the view,
     *                          default is empty.
     * @param string  $region   which region to attach the view, default is
     *                          "main".
     * @param integer $sort     which order to display the views.
     *
     * @return self for chaining.
     */
    public function add($template, $data = [], $region = "main", $sort = 0)
    {
        if (empty($template)) {
            return $this;
        }

        $view = new View();

        if (is_string($template)) {
            $tpl = $this->getTemplateFile($template);
            $type = "file";
        } elseif (is_array($template)) {
            // Can be array with complete view or array with callable callback
            $tpl = $template;
            $type = null;
            $region = isset($tpl["region"])
                ? $tpl["region"]
                : $region;

            if (isset($tpl["callback"])) {
                $tpl["template"] = $template;
                $tpl["type"] = "callback";
            } elseif (isset($tpl["template"])) {
                if (!isset($tpl["type"]) || $tpl["type"] === "file") {
                    $tpl["type"] = "file";
                    $tpl["template"] = $this->getTemplateFile($tpl["template"]);
                }
            }
        }

        $view->set($tpl, $data, $sort, $type);
        $this->views[$region][] = $view;

        return $this;
    }


    /**
     * Add a callback to be rendered as a view.
     *
     * @param string $callback function to call to get the content of the view
     * @param array  $data     variables to make available to the view, default is empty
     * @param string $region   which region to attach the view
     * @param int    $sort     which order to display the views
     *
     * @return $this
     */
    public function addCallback($callback, $data = [], $region = "main", $sort = 0)
    {
        $view = new View();
        $view->set(["callback" => $callback], $data, $sort, "callback");
        $this->views[$region][] = $view;

        return $this;
    }


    /**
     * Add a string as a view.
     *
     * @param string $content the content
     * @param string $region  which region to attach the view
     * @param int    $sort    which order to display the views
     *
     * @return $this
     */
    public function addString($content, $region = "main", $sort = 0)
    {
        $view = new View();
        $view->set($content, [], $sort, "string");
        $this->views[$region][] = $view;
        
        return $this;
    }


    /**
     * Check if a region has views to render.
     *
     * @param string $region which region to check
     *
     * @return $this
     */
    public function hasContent($region)
    {
        return isset($this->views[$region]);
    }


    /**
     * Render all views for a specific region.
     *
     * @param string $region which region to use
     *
     * @return void
     */
    public function render($region = "main")
    {
        if (!isset($this->views[$region])) {
            return $this;
        }

        mergesort($this->views[$region], function ($viewA, $viewB) {
            $sortA = $viewA->sortOrder();
            $sortB = $viewB->sortOrder();

            if ($sortA == $sortB) {
                return 0;
            }

            return $sortA < $sortB ? -1 : 1;
        });

        foreach ($this->views[$region] as $view) {
            $view->render($this->app);
        }
    }


    /**
     * Render all views for a specific region and buffer the result.
     *
     * @param string $region which region to use.
     *
     * @return string with the buffered results.
     */
    public function renderBuffered($region = "main")
    {
        ob_start();
        $this->render($region);
        $res = ob_get_contents();
        ob_end_clean();
        return $res;
    }
}