<?php

/**
 *
 *
 * @author Sebastian Büttner <sebastian.buettner@powerserverplus.net>
 * @package void
 * @version 1.0.0
 * @copyright (c) 2013, powerserverplus.net
 */

class FileNotFoundException extends Exception {}

class Template
{
    /**
     * Whether to use debugging or not
     */
    const DEBUG = true;

    /**
     * @var String Path to tempalte dir
     */
    const template_dir = 'templates';

    /**
     * @var String (sub)template filename
     */
    protected $template = '';

    /**
     * @var Array data to be used within the template
     */
    protected $data;

    /**
     * Template constructor
     *
     * @param String $templ name of the template
     */
    public function __construct($templ, $layout = 'index')
    {
        $this->load($layout);

        $this->data = array();
        $this->assign('subtemplate', $templ);
    }

    /**
     * Save a passed variable for later use in template
     *
     * @param String $name name of the varaible used to identify
     * @param Mixed $value value to be assigned to the variable
     */
    public function assign($name, $value)
    {
        /* Separate name by dot */
        $path = explode('.', $name);

        /* Take the last element of the array, as this is our final identifier */
        $lastKey = array_pop($path);

        /* Create / fill array structure, start with the template`s data base array */
        $parent = &$this->data;

        /* Iterate through the given name structure... */
        foreach ($path as $key)
        {
            /* ...And create substructres where needed */
            if (!isset($parent[$key]))
                $parent[$key] = array();

            /* Move the parent `pointer` deeper within the structure */
            $parent = &$parent[$key];
        }

        /* Finally assign the value to the deepest element in structure */
        $parent[$lastKey] = $value;
    }

    /*
     *
     */
    public function phpize_var($var, $intend = false)
    {
        $php = '';

        switch ( gettype($var) )
        {
            case 'boolean':
                $php .= $var === true ? 'true' : 'false';

                break;

            case 'integer':
            case 'double':
                $php .= $var;

                break;

            case 'string':
                $php .= "'" .
                        str_replace("'", "\\'", $var) .
                        "'";

                break;

            case 'object':
                $php .= '(object)';
            case 'array':
                $php .= 'array(' . ($intend ? "\n" : '') ;

                foreach ($var as $key => $value)
                {
                    $php .= $this->phpize_var($key, $intend) .
                            ' => ' .
                            $this->phpize_var($value, $intend) .
                            ', ';

                    if ($intend)
                        $php .= "\n";
                }

                $php .= ')';

                break;

            case 'NULL':
                $php .= 'NULL';

                break;

            case 'resource':
            default:

        }

        if ($intend)
            $php = str_replace("\n", "\n  ", $php);

        return $php;
    }

    /**
     * Prepare and display the tempalte
     *
     */
    public function display()
    {
        /* We start with no code */
        $template_code = '';

        /* Merge template data with session-flash data */
        $data = $this->data;

        if (isset($_SESSION['appends']) && is_array($_SESSION['appends']) && !empty($_SESSION['appends']))
            $data = array_merge($data, $_SESSION['appends']);

        $_SESSION['appends'] = array();

        /* And iterate then over all passed variables, making them executable code again */
        foreach ($data as $key => $value)
        {
            /* Secure that variables are valid for php */
            if (! preg_match('/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/ims', $key) )
                continue;

            /* Add a new line to the template code */
            $template_code .=
                /* Write varaible name */
                '$' . $key . ' = ' . $this->phpize_var($value, true) . ';' . "\n";

        }

        $template_vars = $template_code;

        /* Put a php close tag, as we are continuing with out html-code-template */
        $template_code .= '?>';

        /* Append the template */
        $template_code .= file_get_contents($this->template);

        /* Execute the build string as PHP-Code */
        eval($template_code);

        /* Debug */

        if (self::DEBUG)
        {
            echo "<div style='display: none; width: 80%; position: absolute; top: 50px; left: 50%; margin-left: -45%; background: url(/images/bg.png); z-index: 1001; border-radius: 8px; border: 4px solid #E6572C; padding: 30px; color: #555; text-shadow: 0 1px 1px #fff ' id='debug'>\n";
            echo "<h3 style='font-style: normal; color: #E6572C; border-bottom: 2px solid #bbb; margin-bottom: 20px;'>Template vars:</h3><pre style='background: #ffffff; border-radius: 2px; border: 1px solid #aaa; padding: 5px; margin: 10px 0;'>" . ($template_vars) . "</pre>";
            echo "</div>";
        }
        echo "<script type='text/javascript'>$(document).ready( function(){ $(document).keypress( function(e){ if (e.keyCode == 100) $('#debug').slideToggle() } ) } );</script>\n";
    }

    /**
     * Includes a given template by name
     *
     * @param String $templ the name of the tempalte file to be included
     */
    static function getInclude($templ)
    {
        /* Build the full path of the file to load */
        $filename = Template::template_dir . '/' . $templ . '.template.php';

        /* Check whether the requested file does exist, if not throw exception */
        if ( ! file_exists($filename) )
            throw new FileNotFoundException('Template file ' . $filename . ' not found.');

        /* return the filename to include */
        return $filename;
    }

    /**
     * Helper function, gives $default back when $var is unset
     *
     * @param Mixed $var
     * @param Mixed $default
     *
     */
    static function withDefault(&$var, $default)
    {
        if (!isset($var))
            return $default;

        return $var;
    }

    /**
     * Try to load template by name, can throw FileNotFoundException
     *
     * @param String $templ template name
     */
    private function load($templ)
    {
        /* Build the full path of the file to load */
        $filename = Template::template_dir . '/' . $templ . '.template.php';

        /* Check whether the requested file does exist, if not throw exception */
        if ( ! file_exists($filename) )
            throw new FileNotFoundException('Template file ' . $filename . ' not found.');

        /* Set the filename of the template */
        $this->template = $filename;
    }


}

?>