<?php

/* Please see the README and LICENSE files. */

/**
 * This class tokenizes, then replacesa some block of text
 */
class Template_Parser {

    /**
     * The text to parse
     * @var String
     */
    protected $text;

    /**
     * The tokens found in the text
     * @var Template_Token[]
     */
    protected $tokens;

    /**
     * The text after replacing the tokens
     * @var String
     */
    protected $parsed_text;

    /**
     * Make new instance, store the text
     * @param String $text 
     */
    public function __construct($text) {
        $this->text = $text;
    }

    /**
     * Parse the text
     * @param String[] $vars Variables in the template
     * @param Data_Model $model A data model to get data from
     * @return String The parsed text 
     */
    public function parse($vars=NULL, $model=NULL) {
        $this->get_tokens();
        $this->parsed_text = $this->text;
        if (is_array($this->tokens)) {
            foreach ($this->tokens as $token) {
                $token->parse($vars, $model);
                $this->parsed_text = str_replace($token->text, $token->parsed, $this->parsed_text);
            }
        }
        return $this->parsed_text;
    }

    protected function get_tokens() {

        $cache_name = "template_" . md5($this->text);
        
        if (!($cached_object = Cache_Subsystem::cache_get($cache_name, Cache_Subsystem::CONTROLLER_FILE)) === false) {
            
        }
            if ($cached_object instanceof $this) {
                $this->tokens = $cached_object->tokens;
                return;
            }

            // Not in cache, tokenize

            if (!isset($this->tokens)) {
                $tfact = new Template_TokenFactory();
                $this->tokens = $tfact->tokenize($this->text);
            }
            if ($cached_object === false) {
                Cache_Subsystem::cache($cache_name, $this, 3600, Cache_Subsystem::CONTROLLER_FILE);
            }
        }

        function __get($name) {
            if (property_exists($this, $name)) {
                return $this->$name;
            }
        }

    }

?>