<?php

/**
 * Smarty Internal Plugin Smarty Template Compiler Base
 * This file contains the basic classes and methods for compiling Smarty templates with lexer/parser
 *
 * @package    Smarty
 * @subpackage Compiler
 * @author     Uwe Tews
 */

/**
 * Main abstract compiler class
 *
 * @package    Smarty
 * @subpackage Compiler
 *
 * @property Smarty_Internal_SmartyTemplateCompiler $prefixCompiledCode  = ''
 * @property Smarty_Internal_SmartyTemplateCompiler $postfixCompiledCode = ''
 * @method registerPostCompileCallback($callback, $parameter = array(), $key = null, $replace = false)
 * @method unregisterPostCompileCallback($key)
 */
abstract class Smarty_Internal_TemplateCompilerBase
{

    /**
     * Smarty object
     *
     * @var Smarty
     */
    public $smarty = null;

    /**
     * Parser object
     *
     * @var Smarty_Internal_Templateparser
     */
    public $parser = null;

    /**
     * hash for nocache sections
     *
     * @var mixed
     */
    public $nocache_hash = null;

    /**
     * suppress generation of nocache code
     *
     * @var bool
     */
    public $suppressNocacheProcessing = false;

    /**
     * compile tag objects cache
     *
     * @var array
     */
    static $_tag_objects = array();

    /**
     * tag stack
     *
     * @var array
     */
    public $_tag_stack = array();

    /**
     * current template
     *
     * @var Smarty_Internal_Template
     */
    public $template = null;

    /**
     * merged included sub template data
     *
     * @var array
     */
    public $mergedSubTemplatesData = array();

    /**
     * merged sub template code
     *
     * @var array
     */
    public $mergedSubTemplatesCode = array();

    /**
     * collected template properties during compilation
     *
     * @var array
     */
    public $templateProperties = array();

    /**
     * source line offset for error messages
     *
     * @var int
     */
    public $trace_line_offset = 0;

    /**
     * trace uid
     *
     * @var string
     */
    public $trace_uid = '';

    /**
     * trace file path
     *
     * @var string
     */
    public $trace_filepath = '';

    /**
     * stack for tracing file and line of nested {block} tags
     *
     * @var array
     */
    public $trace_stack = array();

    /**
     * plugins loaded by default plugin handler
     *
     * @var array
     */
    public $default_handler_plugins = array();

    /**
     * saved preprocessed modifier list
     *
     * @var mixed
     */
    public $default_modifier_list = null;

    /**
     * force compilation of complete template as nocache
     *
     * @var boolean
     */
    public $forceNocache = false;

    /**
     * flag if compiled template file shall we written
     *
     * @var bool
     */
    public $write_compiled_code = true;

    /**
     * Template functions
     *
     * @var array
     */
    public $tpl_function = array();

    /**
     * called sub functions from template function
     *
     * @var array
     */
    public $called_functions = array();

    /**
     * compiled template or block function code
     *
     * @var string
     */
    public $blockOrFunctionCode = '';

    /**
     * php_handling setting either from Smarty or security
     *
     * @var int
     */
    public $php_handling = 0;

    /**
     * flags for used modifier plugins
     *
     * @var array
     */
    public $modifier_plugins = array();

    /**
     * type of already compiled modifier
     *
     * @var array
     */
    public $known_modifier_type = array();

    /**
     * parent compiler object for merged subtemplates and template functions
     *
     * @var Smarty_Internal_TemplateCompilerBase
     */
    public $parent_compiler = null;

    /**
     * Flag true when compiling nocache section
     *
     * @var bool
     */
    public $nocache = false;

    /**
     * Flag true when tag is compiled as nocache
     *
     * @var bool
     */
    public $tag_nocache = false;

    /**
     * Compiled tag prefix code
     *
     * @var array
     */
    public $prefix_code = array();

    /**
     * Prefix code  stack
     *
     * @var array
     */
    public $prefixCodeStack = array();

    /**
     * Tag has compiled code
     *
     * @var bool
     */
    public $has_code = false;

    /**
     * A variable string was compiled
     *
     * @var bool
     */
    public $has_variable_string = false;

    /**
     * Tag creates output
     *
     * @var bool
     */
    public $has_output = false;

    /**
     * Stack for {setfilter} {/setfilter}
     *
     * @var array
     */
    public $variable_filter_stack = array();

    /**
     * variable filters for {setfilter} {/setfilter}
     *
     * @var array
     */
    public $variable_filters = array();

    /**
     * Nesting count of looping tags like {foreach}, {for}, {section}, {while}
     *
     * @var int
     */
    public $loopNesting = 0;

    /**
     * Strip preg pattern
     *
     * @var string
     */
    public $stripRegEx = '![\t ]*[\r\n]+[\t ]*!';

    /**
     * plugin search order
     *
     * @var array
     */
    public $plugin_search_order = array('function', 'block', 'compiler', 'class');

    /**
     * General storage area for tag compiler plugins
     *
     * @var array
     */
    public $_cache = array();

    /**
     * counter for prefix variable number
     *
     * @var int
     */
    public static $prefixVariableNumber = 0;

    /**
     * method to compile a Smarty template
     *
     * @param mixed $_content template source
     * @param bool  $isTemplateSource
     *
     * @return bool true if compiling succeeded, false if it failed
     */
    abstract protected function doCompile($_content, $isTemplateSource = false);

    /**
     * Initialize compiler
     *
     * @param Smarty $smarty global instance
     */
    public function __construct(Smarty $smarty)
    {
        $this->smarty = $smarty;
        $this->nocache_hash = str_replace(array('.', ','), '_', uniqid(rand(), true));
    }

    /**
     * Method to compile a Smarty template
     *
     * @param  Smarty_Internal_Template                 $template template object to compile
     * @param  bool                                     $nocache  true is shall be compiled in nocache mode
     * @param null|Smarty_Internal_TemplateCompilerBase $parent_compiler
     *
     * @return bool true if compiling succeeded, false if it failed
     * @throws \Exception
     */
    public function compileTemplate(Smarty_Internal_Template $template, $nocache = null,
                                    Smarty_Internal_TemplateCompilerBase $parent_compiler = null)
    {
        // get code frame of compiled template
        $_compiled_code = $template->smarty->ext->_codeFrame->create($template,
                                                                     $this->compileTemplateSource($template, $nocache,
                                                                                                  $parent_compiler),
                                                                     $this->postFilter($this->blockOrFunctionCode) .
                                                                     join('', $this->mergedSubTemplatesCode), false,
                                                                     $this);
        return $_compiled_code;
    }

    /**
     * Compile template source and run optional post filter
     *
     * @param \Smarty_Internal_Template             $template
     * @param null|bool                             $nocache flag if template must be compiled in nocache mode
     * @param \Smarty_Internal_TemplateCompilerBase $parent_compiler
     *
     * @return string
     * @throws \Exception
     */
    public function compileTemplateSource(Smarty_Internal_Template $template, $nocache = null,
                                          Smarty_Internal_TemplateCompilerBase $parent_compiler = null)
    {
        try {
            // save template object in compiler class
            $this->template = $template;
            if (property_exists($this->template->smarty, 'plugin_search_order')) {
                $this->plugin_search_order = $this->template->smarty->plugin_search_order;
            }
            if ($this->smarty->debugging) {
                if (!isset($this->smarty->_debug)) {
                    $this->smarty->_debug = new Smarty_Internal_Debug();
                }
                $this->smarty->_debug->start_compile($this->template);
            }
            if (isset($this->template->smarty->security_policy)) {
                $this->php_handling = $this->template->smarty->security_policy->php_handling;
            } else {
                $this->php_handling = $this->template->smarty->php_handling;
            }
            $this->parent_compiler = $parent_compiler ? $parent_compiler : $this;
            $nocache = isset($nocache) ? $nocache : false;
            if (empty($template->compiled->nocache_hash)) {
                $template->compiled->nocache_hash = $this->nocache_hash;
            } else {
                $this->nocache_hash = $template->compiled->nocache_hash;
            }
            // flag for nocache sections
            $this->nocache = $nocache;
            $this->tag_nocache = false;
            // reset has nocache code flag
            $this->template->compiled->has_nocache_code = false;
            $this->has_variable_string = false;
            $this->prefix_code = array();
            // add file dependency
            if ($this->smarty->merge_compiled_includes || $this->template->source->handler->checkTimestamps()) {
                $this->parent_compiler->template->compiled->file_dependency[ $this->template->source->uid ] =
                    array($this->template->source->filepath, $this->template->source->getTimeStamp(),
                          $this->template->source->type,);
            }
            $this->smarty->_current_file = $this->template->source->filepath;
            // get template source
            if (!empty($this->template->source->components)) {
                // we have array of inheritance templates by extends: resource
                // generate corresponding source code sequence
                $_content =
                    Smarty_Internal_Compile_Extends::extendsSourceArrayCode($this->template->source->components);
            } else {
                // get template source
                $_content = $this->template->source->getContent();
            }
            $_compiled_code = $this->postFilter($this->doCompile($this->preFilter($_content), true));
        }
        catch (Exception $e) {
            if ($this->smarty->debugging) {
                $this->smarty->_debug->end_compile($this->template);
            }
            $this->_tag_stack = array();
            // free memory
            $this->parent_compiler = null;
            $this->template = null;
            $this->parser = null;
            throw $e;
        }
        if ($this->smarty->debugging) {
            $this->smarty->_debug->end_compile($this->template);
        }
        $this->parent_compiler = null;
        $this->parser = null;
        return $_compiled_code;
    }

    /**
     * Optionally process compiled code by post filter
     *
     * @param string $code compiled code
     *
     * @return string
     * @throws \SmartyException
     */
    public function postFilter($code)
    {
        // run post filter if on code
        if (!empty($code) &&
            (isset($this->smarty->autoload_filters[ 'post' ]) || isset($this->smarty->registered_filters[ 'post' ]))
        ) {
            return $this->smarty->ext->_filterHandler->runFilter('post', $code, $this->template);
        } else {
            return $code;
        }
    }

    /**
     * Run optional prefilter
     *
     * @param string $_content template source
     *
     * @return string
     * @throws \SmartyException
     */
    public function preFilter($_content)
    {
        // run pre filter if required
        if ($_content != '' &&
            ((isset($this->smarty->autoload_filters[ 'pre' ]) || isset($this->smarty->registered_filters[ 'pre' ])))
        ) {
            return $this->smarty->ext->_filterHandler->runFilter('pre', $_content, $this->template);
        } else {
            return $_content;
        }
    }

    /**
     * Compile Tag
     * This is a call back from the lexer/parser
     *
     * Save current prefix code
     * Compile tag
     * Merge tag prefix code with saved one
     * (required nested tags in attributes)
     *
     * @param  string $tag       tag name
     * @param  array  $args      array with tag attributes
     * @param  array  $parameter array with compilation parameter
     *
     * @throws SmartyCompilerException
     * @throws SmartyException
     * @return string compiled code
     */
    public function compileTag($tag, $args, $parameter = array())
    {
        $this->prefixCodeStack[] = $this->prefix_code;
        $this->prefix_code = array();
        $result = $this->compileTag2($tag, $args, $parameter);
        $this->prefix_code = array_merge($this->prefix_code, array_pop($this->prefixCodeStack));
        return $result;
    }

    /**
     * Compile Tag
     *
     * @param  string $tag       tag name
     * @param  array  $args      array with tag attributes
     * @param  array  $parameter array with compilation parameter
     *
     * @throws SmartyCompilerException
     * @throws SmartyException
     * @return string compiled code
     */
    private function compileTag2($tag, $args, $parameter)
    {
        $plugin_type = '';
        // $args contains the attributes parsed and compiled by the lexer/parser
        // assume that tag does compile into code, but creates no HTML output
        $this->has_code = true;
        $this->has_output = false;
        // log tag/attributes
        if (isset($this->smarty->_cache[ 'get_used_tags' ])) {
            $this->template->_cache[ 'used_tags' ][] = array($tag, $args);
        }
        // check nocache option flag
        foreach ($args as $arg) {
            if (!is_array($arg)) {
                if ($arg == "'nocache'") {
                    $this->tag_nocache = true;
                }
            } else {
                foreach ($arg as $k => $v) {
                    if ($k == "'nocache'" && (trim($v, "'\" ") == 'true')) {
                        $this->tag_nocache = true;
                    }
                }
            }
        }
        // compile the smarty tag (required compile classes to compile the tag are auto loaded)
        if (($_output = $this->callTagCompiler($tag, $args, $parameter)) === false) {
            if (isset($this->parent_compiler->tpl_function[ $tag ])) {
                // template defined by {template} tag
                $args[ '_attr' ][ 'name' ] = "'" . $tag . "'";
                $_output = $this->callTagCompiler('call', $args, $parameter);
            }
        }
        if ($_output !== false) {
            if ($_output !== true) {
                // did we get compiled code
                if ($this->has_code) {
                    // Does it create output?
                    if ($this->has_output) {
                        $_output .= "\n";
                    }
                    // return compiled code
                    return $_output;
                }
            }
            // tag did not produce compiled code
            return null;
        } else {
            // map_named attributes
            if (isset($args[ '_attr' ])) {
                foreach ($args[ '_attr' ] as $key => $attribute) {
                    if (is_array($attribute)) {
                        $args = array_merge($args, $attribute);
                    }
                }
            }
            // not an internal compiler tag
            if (strlen($tag) < 6 || substr($tag, - 5) != 'close') {
                // check if tag is a registered object
                if (isset($this->smarty->registered_objects[ $tag ]) && isset($parameter[ 'object_method' ])) {
                    $method = $parameter[ 'object_method' ];
                    if (!in_array($method, $this->smarty->registered_objects[ $tag ][ 3 ]) &&
                        (empty($this->smarty->registered_objects[ $tag ][ 1 ]) ||
                         in_array($method, $this->smarty->registered_objects[ $tag ][ 1 ]))
                    ) {
                        return $this->callTagCompiler('private_object_function', $args, $parameter, $tag, $method);
                    } elseif (in_array($method, $this->smarty->registered_objects[ $tag ][ 3 ])) {
                        return $this->callTagCompiler('private_object_block_function', $args, $parameter, $tag,
                                                      $method);
                    } else {
                        // throw exception
                        $this->trigger_template_error('not allowed method "' . $method . '" in registered object "' .
                                                      $tag . '"', null, true);
                    }
                }
                // check if tag is registered
                foreach (array(Smarty::PLUGIN_COMPILER, Smarty::PLUGIN_FUNCTION, Smarty::PLUGIN_BLOCK,) as $plugin_type)
                {
                    if (isset($this->smarty->registered_plugins[ $plugin_type ][ $tag ])) {
                        // if compiler function plugin call it now
                        if ($plugin_type == Smarty::PLUGIN_COMPILER) {
                            $new_args = array();
                            foreach ($args as $key => $mixed) {
                                if (is_array($mixed)) {
                                    $new_args = array_merge($new_args, $mixed);
                                } else {
                                    $new_args[ $key ] = $mixed;
                                }
                            }
                            if (!$this->smarty->registered_plugins[ $plugin_type ][ $tag ][ 1 ]) {
                                $this->tag_nocache = true;
                            }
                            return call_user_func_array($this->smarty->registered_plugins[ $plugin_type ][ $tag ][ 0 ],
                                                        array($new_args, $this));
                        }
                        // compile registered function or block function
                        if ($plugin_type == Smarty::PLUGIN_FUNCTION || $plugin_type == Smarty::PLUGIN_BLOCK) {
                            return $this->callTagCompiler('private_registered_' . $plugin_type, $args, $parameter,
                                                          $tag);
                        }
                    }
                }
                // check plugins from plugins folder
                foreach ($this->plugin_search_order as $plugin_type) {
                    if ($plugin_type == Smarty::PLUGIN_COMPILER &&
                        $this->smarty->loadPlugin('smarty_compiler_' . $tag) &&
                        (!isset($this->smarty->security_policy) ||
                         $this->smarty->security_policy->isTrustedTag($tag, $this))
                    ) {
                        $plugin = 'smarty_compiler_' . $tag;
                        if (is_callable($plugin)) {
                            // convert arguments format for old compiler plugins
                            $new_args = array();
                            foreach ($args as $key => $mixed) {
                                if (is_array($mixed)) {
                                    $new_args = array_merge($new_args, $mixed);
                                } else {
                                    $new_args[ $key ] = $mixed;
                                }
                            }

                            return $plugin($new_args, $this->smarty);
                        }
                        if (class_exists($plugin, false)) {
                            $plugin_object = new $plugin;
                            if (method_exists($plugin_object, 'compile')) {
                                return $plugin_object->compile($args, $this);
                            }
                        }
                        throw new SmartyException("Plugin \"{$tag}\" not callable");
                    } else {
                        if ($function = $this->getPlugin($tag, $plugin_type)) {
                            if (!isset($this->smarty->security_policy) ||
                                $this->smarty->security_policy->isTrustedTag($tag, $this)
                            ) {
                                return $this->callTagCompiler('private_' . $plugin_type . '_plugin', $args, $parameter,
                                                              $tag, $function);
                            }
                        }
                    }
                }
                if (is_callable($this->smarty->default_plugin_handler_func)) {
                    $found = false;
                    // look for already resolved tags
                    foreach ($this->plugin_search_order as $plugin_type) {
                        if (isset($this->default_handler_plugins[ $plugin_type ][ $tag ])) {
                            $found = true;
                            break;
                        }
                    }
                    if (!$found) {
                        // call default handler
                        foreach ($this->plugin_search_order as $plugin_type) {
                            if ($this->getPluginFromDefaultHandler($tag, $plugin_type)) {
                                $found = true;
                                break;
                            }
                        }
                    }
                    if ($found) {
                        // if compiler function plugin call it now
                        if ($plugin_type == Smarty::PLUGIN_COMPILER) {
                            $new_args = array();
                            foreach ($args as $mixed) {
                                $new_args = array_merge($new_args, $mixed);
                            }
                            return call_user_func_array($this->default_handler_plugins[ $plugin_type ][ $tag ][ 0 ],
                                                        array($new_args, $this));
                        } else {
                            return $this->callTagCompiler('private_registered_' . $plugin_type, $args, $parameter,
                                                          $tag);
                        }
                    }
                }
            } else {
                // compile closing tag of block function
                $base_tag = substr($tag, 0, - 5);
                // check if closing tag is a registered object
                if (isset($this->smarty->registered_objects[ $base_tag ]) && isset($parameter[ 'object_method' ])) {
                    $method = $parameter[ 'object_method' ];
                    if (in_array($method, $this->smarty->registered_objects[ $base_tag ][ 3 ])) {
                        return $this->callTagCompiler('private_object_block_function', $args, $parameter, $tag,
                                                      $method);
                    } else {
                        // throw exception
                        $this->trigger_template_error('not allowed closing tag method "' . $method .
                                                      '" in registered object "' . $base_tag . '"', null, true);
                    }
                }
                // registered block tag ?
                if (isset($this->smarty->registered_plugins[ Smarty::PLUGIN_BLOCK ][ $base_tag ]) ||
                    isset($this->default_handler_plugins[ Smarty::PLUGIN_BLOCK ][ $base_tag ])
                ) {
                    return $this->callTagCompiler('private_registered_block', $args, $parameter, $tag);
                }
                // registered function tag ?
                if (isset($this->smarty->registered_plugins[ Smarty::PLUGIN_FUNCTION ][ $tag ])) {
                    return $this->callTagCompiler('private_registered_function', $args, $parameter, $tag);
                }
                // block plugin?
                if ($function = $this->getPlugin($base_tag, Smarty::PLUGIN_BLOCK)) {
                    return $this->callTagCompiler('private_block_plugin', $args, $parameter, $tag, $function);
                }
                // function plugin?
                if ($function = $this->getPlugin($tag, Smarty::PLUGIN_FUNCTION)) {
                    if (!isset($this->smarty->security_policy) ||
                        $this->smarty->security_policy->isTrustedTag($tag, $this)
                    ) {
                        return $this->callTagCompiler('private_function_plugin', $args, $parameter, $tag, $function);
                    }
                }
                // registered compiler plugin ?
                if (isset($this->smarty->registered_plugins[ Smarty::PLUGIN_COMPILER ][ $tag ])) {
                    // if compiler function plugin call it now
                    $args = array();
                    if (!$this->smarty->registered_plugins[ Smarty::PLUGIN_COMPILER ][ $tag ][ 1 ]) {
                        $this->tag_nocache = true;
                    }
                    return call_user_func_array($this->smarty->registered_plugins[ Smarty::PLUGIN_COMPILER ][ $tag ][ 0 ],
                                                array($args, $this));
                }
                if ($this->smarty->loadPlugin('smarty_compiler_' . $tag)) {
                    $plugin = 'smarty_compiler_' . $tag;
                    if (is_callable($plugin)) {
                        return $plugin($args, $this->smarty);
                    }
                    if (class_exists($plugin, false)) {
                        $plugin_object = new $plugin;
                        if (method_exists($plugin_object, 'compile')) {
                            return $plugin_object->compile($args, $this);
                        }
                    }
                    throw new SmartyException("Plugin \"{$tag}\" not callable");
                }
            }
            $this->trigger_template_error("unknown tag \"" . $tag . "\"", null, true);
        }
    }

    /**
     * compile variable
     *
     * @param string $variable
     *
     * @return string
     */
    public function compileVariable($variable)
    {
        if (strpos($variable, '(') == 0) {
            // not a variable variable
            $var = trim($variable, '\'');
            $this->tag_nocache = $this->tag_nocache |
                                 $this->template->ext->getTemplateVars->_getVariable($this->template, $var, null, true,
                                                                                     false)->nocache;
            // todo $this->template->compiled->properties['variables'][$var] = $this->tag_nocache | $this->nocache;
        }
        return '$_smarty_tpl->tpl_vars[' . $variable . ']->value';
    }

    /**
     * compile config variable
     *
     * @param string $variable
     *
     * @return string
     */
    public function compileConfigVariable($variable)
    {
        // return '$_smarty_tpl->config_vars[' . $variable . ']';
        return '$_smarty_tpl->smarty->ext->configLoad->_getConfigVariable($_smarty_tpl, ' . $variable . ')';
    }

    /**
     * This method is called from parser to process a text content section
     * - remove text from inheritance child templates as they may generate output
     * - strip text if strip is enabled
     *
     * @param string $text
     *
     * @return null|\Smarty_Internal_ParseTree_Text
     */
    public function processText($text)
    {
        if ((string) $text != '') {
            $store = array();
            $_store = 0;
            if ($this->parser->strip) {
                if (strpos($text, '<') !== false) {
                    // capture html elements not to be messed with
                    $_offset = 0;
                    if (preg_match_all('#(<script[^>]*>.*?</script[^>]*>)|(<textarea[^>]*>.*?</textarea[^>]*>)|(<pre[^>]*>.*?</pre[^>]*>)#is',
                                       $text, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
                        foreach ($matches as $match) {
                            $store[] = $match[ 0 ][ 0 ];
                            $_length = strlen($match[ 0 ][ 0 ]);
                            $replace = '@!@SMARTY:' . $_store . ':SMARTY@!@';
                            $text = substr_replace($text, $replace, $match[ 0 ][ 1 ] - $_offset, $_length);

                            $_offset += $_length - strlen($replace);
                            $_store ++;
                        }
                    }
                    $expressions = array(// replace multiple spaces between tags by a single space
                                         '#(:SMARTY@!@|>)[\040\011]+(?=@!@SMARTY:|<)#s' => '\1 \2',
                                         // remove newline between tags
                                         '#(:SMARTY@!@|>)[\040\011]*[\n]\s*(?=@!@SMARTY:|<)#s' => '\1\2',
                                         // remove multiple spaces between attributes (but not in attribute values!)
                                         '#(([a-z0-9]\s*=\s*("[^"]*?")|(\'[^\']*?\'))|<[a-z0-9_]+)\s+([a-z/>])#is' => '\1 \5',
                                         '#>[\040\011]+$#Ss' => '> ', '#>[\040\011]*[\n]\s*$#Ss' => '>',
                                         $this->stripRegEx => '',);

                    $text = preg_replace(array_keys($expressions), array_values($expressions), $text);
                    $_offset = 0;
                    if (preg_match_all('#@!@SMARTY:([0-9]+):SMARTY@!@#is', $text, $matches,
                                       PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
                        foreach ($matches as $match) {
                            $_length = strlen($match[ 0 ][ 0 ]);
                            $replace = $store[ $match[ 1 ][ 0 ] ];
                            $text = substr_replace($text, $replace, $match[ 0 ][ 1 ] + $_offset, $_length);

                            $_offset += strlen($replace) - $_length;
                            $_store ++;
                        }
                    }
                } else {
                    $text = preg_replace($this->stripRegEx, '', $text);
                }
            }
            return new Smarty_Internal_ParseTree_Text($text);
        }
        return null;
    }

    /**
     * lazy loads internal compile plugin for tag and calls the compile method
     * compile objects cached for reuse.
     * class name format:  Smarty_Internal_Compile_TagName
     * plugin filename format: Smarty_Internal_TagName.php
     *
     * @param  string $tag    tag name
     * @param  array  $args   list of tag attributes
     * @param  mixed  $param1 optional parameter
     * @param  mixed  $param2 optional parameter
     * @param  mixed  $param3 optional parameter
     *
     * @return string compiled code
     */
    public function callTagCompiler($tag, $args, $param1 = null, $param2 = null, $param3 = null)
    {
        // re-use object if already exists
        if (!isset(self::$_tag_objects[ $tag ])) {
            // lazy load internal compiler plugin
            $_tag = explode('_', $tag);
            $_tag = array_map('ucfirst', $_tag);
            $class_name = 'Smarty_Internal_Compile_' . implode('_', $_tag);
            if (class_exists($class_name) &&
                (!isset($this->smarty->security_policy) || $this->smarty->security_policy->isTrustedTag($tag, $this))
            ) {
                self::$_tag_objects[ $tag ] = new $class_name;
            } else {
                self::$_tag_objects[ $tag ] = false;
                return false;
            }
        }
        // compile this tag
        return self::$_tag_objects[ $tag ] === false ? false :
            self::$_tag_objects[ $tag ]->compile($args, $this, $param1, $param2, $param3);
    }

    /**
     * Check for plugins and return function name
     *
     * @param         $plugin_name
     * @param  string $plugin_type type of plugin
     *
     * @return string call name of function
     */
    public function getPlugin($plugin_name, $plugin_type)
    {
        $function = null;
        if ($this->template->caching && ($this->nocache || $this->tag_nocache)) {
            if (isset($this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ])) {
                $function =
                    $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ][ 'function' ];
            } elseif (isset($this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ])) {
                $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ] =
                    $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ];
                $function =
                    $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ][ 'function' ];
            }
        } else {
            if (isset($this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ])) {
                $function =
                    $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ][ 'function' ];
            } elseif (isset($this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ])) {
                $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ] =
                    $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ];
                $function =
                    $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ][ 'function' ];
            }
        }
        if (isset($function)) {
            if ($plugin_type == 'modifier') {
                $this->modifier_plugins[ $plugin_name ] = true;
            }

            return $function;
        }
        // loop through plugin dirs and find the plugin
        $function = 'smarty_' . $plugin_type . '_' . $plugin_name;
        $file = $this->smarty->loadPlugin($function, false);

        if (is_string($file)) {
            if ($this->template->caching && ($this->nocache || $this->tag_nocache)) {
                $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ][ 'file' ] =
                    $file;
                $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ $plugin_type ][ 'function' ] =
                    $function;
            } else {
                $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ][ 'file' ] =
                    $file;
                $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ $plugin_type ][ 'function' ] =
                    $function;
            }
            if ($plugin_type == 'modifier') {
                $this->modifier_plugins[ $plugin_name ] = true;
            }

            return $function;
        }
        if (is_callable($function)) {
            // plugin function is defined in the script
            return $function;
        }

        return false;
    }

    /**
     * Check for plugins by default plugin handler
     *
     * @param  string $tag         name of tag
     * @param  string $plugin_type type of plugin
     *
     * @return boolean true if found
     */
    public function getPluginFromDefaultHandler($tag, $plugin_type)
    {
        $callback = null;
        $script = null;
        $cacheable = true;
        $result = call_user_func_array($this->smarty->default_plugin_handler_func,
                                       array($tag, $plugin_type, $this->template, &$callback, &$script, &$cacheable,));
        if ($result) {
            $this->tag_nocache = $this->tag_nocache || !$cacheable;
            if ($script !== null) {
                if (is_file($script)) {
                    if ($this->template->caching && ($this->nocache || $this->tag_nocache)) {
                        $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $tag ][ $plugin_type ][ 'file' ] =
                            $script;
                        $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $tag ][ $plugin_type ][ 'function' ] =
                            $callback;
                    } else {
                        $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $tag ][ $plugin_type ][ 'file' ] =
                            $script;
                        $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $tag ][ $plugin_type ][ 'function' ] =
                            $callback;
                    }
                    require_once $script;
                } else {
                    $this->trigger_template_error("Default plugin handler: Returned script file \"{$script}\" for \"{$tag}\" not found");
                }
            }
            if (is_callable($callback)) {
                $this->default_handler_plugins[ $plugin_type ][ $tag ] = array($callback, true, array());

                return true;
            } else {
                $this->trigger_template_error("Default plugin handler: Returned callback for \"{$tag}\" not callable");
            }
        }

        return false;
    }

    /**
     * Append code segments and remove unneeded ?> <?php transitions
     *
     * @param string $left
     * @param string $right
     *
     * @return string
     */
    public function appendCode($left, $right)
    {
        if (preg_match('/\s*\?>\s*$/', $left) && preg_match('/^\s*<\?php\s+/', $right)) {
            $left = preg_replace('/\s*\?>\s*$/', "\n", $left);
            $left .= preg_replace('/^\s*<\?php\s+/', '', $right);
        } else {
            $left .= $right;
        }
        return $left;
    }

    /**
     * Inject inline code for nocache template sections
     * This method gets the content of each template element from the parser.
     * If the content is compiled code and it should be not cached the code is injected
     * into the rendered output.
     *
     * @param  string  $content content of template element
     * @param  boolean $is_code true if content is compiled code
     *
     * @return string  content
     */
    public function processNocacheCode($content, $is_code)
    {
        // If the template is not evaluated and we have a nocache section and or a nocache tag
        if ($is_code && !empty($content)) {
            // generate replacement code
            if ((!($this->template->source->handler->recompiled) || $this->forceNocache) && $this->template->caching &&
                !$this->suppressNocacheProcessing && ($this->nocache || $this->tag_nocache)
            ) {
                $this->template->compiled->has_nocache_code = true;
                $_output = addcslashes($content, '\'\\');
                $_output = str_replace("^#^", "'", $_output);
                $_output = "<?php echo '/*%%SmartyNocache:{$this->nocache_hash}%%*/" . $_output .
                           "/*/%%SmartyNocache:{$this->nocache_hash}%%*/';?>\n";
                // make sure we include modifier plugins for nocache code
                foreach ($this->modifier_plugins as $plugin_name => $dummy) {
                    if (isset($this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ 'modifier' ])) {
                        $this->parent_compiler->template->compiled->required_plugins[ 'nocache' ][ $plugin_name ][ 'modifier' ] =
                            $this->parent_compiler->template->compiled->required_plugins[ 'compiled' ][ $plugin_name ][ 'modifier' ];
                    }
                }
            } else {
                $_output = $content;
            }
        } else {
            $_output = $content;
        }
        $this->modifier_plugins = array();
        $this->suppressNocacheProcessing = false;
        $this->tag_nocache = false;

        return $_output;
    }

    /**
     * Get Id
     *
     * @param string $input
     *
     * @return bool|string
     */
    public function getId($input)
    {
        if (preg_match('~^([\'"]*)([0-9]*[a-zA-Z_]\w*)\1$~', $input, $match)) {
            return $match[ 2 ];
        }
        return false;
    }

    /**
     * Get variable name from string
     *
     * @param string $input
     *
     * @return bool|string
     */
    public function getVariableName($input)
    {
        if (preg_match('~^[$]_smarty_tpl->tpl_vars\[[\'"]*([0-9]*[a-zA-Z_]\w*)[\'"]*\]->value$~', $input, $match)) {
            return $match[ 1 ];
        }
        return false;
    }

    /**
     * Set nocache flag in variable or create new variable
     *
     * @param string $varName
     */
    public function setNocacheInVariable($varName)
    {
        // create nocache var to make it know for further compiling
        if ($_var = $this->getId($varName)) {
            if (isset($this->template->tpl_vars[ $_var ])) {
                $this->template->tpl_vars[ $_var ] = clone $this->template->tpl_vars[ $_var ];
                $this->template->tpl_vars[ $_var ]->nocache = true;
            } else {
                $this->template->tpl_vars[ $_var ] = new Smarty_Variable(null, true);
            }
        }
    }

    /**
     * @param array $_attr tag attributes
     * @param array $validScopes
     *
     * @return int|string
     * @throws \SmartyCompilerException
     */
    public function convertScope($_attr, $validScopes)
    {
        $_scope = 0;
        if (isset($_attr[ 'scope' ])) {
            $_scopeName = trim($_attr[ 'scope' ], "'\"");
            if (is_numeric($_scopeName) && in_array($_scopeName, $validScopes)) {
                $_scope = $_scopeName;
            } elseif (is_string($_scopeName)) {
                $_scopeName = trim($_scopeName, "'\"");
                $_scope = isset($validScopes[ $_scopeName ]) ? $validScopes[ $_scopeName ] : false;
            } else {
                $_scope = false;
            }
            if ($_scope === false) {
                $err = var_export($_scopeName, true);
                $this->trigger_template_error("illegal value '{$err}' for \"scope\" attribute", null, true);
            }
        }
        return $_scope;
    }

    /**
     * Generate nocache code string
     *
     * @param string $code PHP code
     *
     * @return string
     */
    public function makeNocacheCode($code)
    {
        return "echo '/*%%SmartyNocache:{$this->nocache_hash}%%*/<?php " .
               str_replace("^#^", "'", addcslashes($code, '\'\\')) .
               "?>/*/%%SmartyNocache:{$this->nocache_hash}%%*/';\n";
    }

    /**
     * display compiler error messages without dying
     * If parameter $args is empty it is a parser detected syntax error.
     * In this case the parser is called to obtain information about expected tokens.
     * If parameter $args contains a string this is used as error message
     *
     * @param  string   $args    individual error message or null
     * @param  string   $line    line-number
     * @param null|bool $tagline if true the line number of last tag
     *
     * @throws \SmartyCompilerException when an unexpected token is found
     */
    public function trigger_template_error($args = null, $line = null, $tagline = null)
    {
        $lex = $this->parser->lex;
        if ($tagline === true) {
            // get line number of Tag
            $line = $lex->taglineno;
        } elseif (!isset($line)) {
            // get template source line which has error
            $line = $lex->line;
        } else {
            $line = (int) $line;
        }

        if (in_array($this->template->source->type, array('eval', 'string'))) {
            $templateName = $this->template->source->type . ':' . trim(preg_replace('![\t\r\n]+!', ' ',
                                                                                    strlen($lex->data) > 40 ?
                                                                                        substr($lex->data, 0, 40) .
                                                                                        '...' : $lex->data));
        } else {
            $templateName = $this->template->source->type . ':' . $this->template->source->filepath;
        }

        //        $line += $this->trace_line_offset;
        $match = preg_split("/\n/", $lex->data);
        $error_text =
            'Syntax error in template "' . (empty($this->trace_filepath) ? $templateName : $this->trace_filepath) .
            '"  on line ' . ($line + $this->trace_line_offset) . ' "' .
            trim(preg_replace('![\t\r\n]+!', ' ', $match[ $line - 1 ])) . '" ';
        if (isset($args)) {
            // individual error message
            $error_text .= $args;
        } else {
            $expect = array();
            // expected token from parser
            $error_text .= ' - Unexpected "' . $lex->value . '"';
            if (count($this->parser->yy_get_expected_tokens($this->parser->yymajor)) <= 4) {
                foreach ($this->parser->yy_get_expected_tokens($this->parser->yymajor) as $token) {
                    $exp_token = $this->parser->yyTokenName[ $token ];
                    if (isset($lex->smarty_token_names[ $exp_token ])) {
                        // token type from lexer
                        $expect[] = '"' . $lex->smarty_token_names[ $exp_token ] . '"';
                    } else {
                        // otherwise internal token name
                        $expect[] = $this->parser->yyTokenName[ $token ];
                    }
                }
                $error_text .= ', expected one of: ' . implode(' , ', $expect);
            }
        }
        $e = new SmartyCompilerException($error_text);
        $e->line = $line;
        $e->source = trim(preg_replace('![\t\r\n]+!', ' ', $match[ $line - 1 ]));
        $e->desc = $args;
        $e->template = $this->template->source->filepath;
        throw $e;
    }

    /**
     * Return var_export() value with all white spaces removed
     *
     * @param  mixed $value
     *
     * @return string
     */
    public function getVarExport($value)
    {
        return preg_replace('/\s/', '', var_export($value, true));
    }

    /**
     * Check if $value contains variable elements
     *
     * @param mixed $value
     *
     * @return bool|int
     */
    public function isVariable($value)
    {
        if (is_string($value)) {
            return preg_match('/[$(]/', $value);
        }
        if (is_bool($value) || is_numeric($value)) {
            return false;
        }
        if (is_array($value)) {
            foreach ($value as $k => $v) {
                if ($this->isVariable($k) || $this->isVariable($v)) {
                    return true;
                }
            }
            return false;
        }
        return false;
    }

    /**
     * Get new prefix variable name
     *
     * @return string
     */
    public function getNewPrefixVariable()
    {
        self::$prefixVariableNumber ++;
        return $this->getPrefixVariable();
    }

    /**
     * Get current prefix variable name
     *
     * @return string
     */
    public function getPrefixVariable()
    {
        return '$_prefixVariable' . self::$prefixVariableNumber;
    }

    /**
     * append  code to prefix buffer
     *
     * @param string $code
     */
    public function appendPrefixCode($code)
    {
        $this->prefix_code[] = $code;
    }

    /**
     * get prefix code string
     *
     * @return string
     */
    public function getPrefixCode()
    {
        $code = '';
        $prefixArray = array_merge($this->prefix_code, array_pop($this->prefixCodeStack));
        $this->prefixCodeStack[] = array();
        foreach ($prefixArray as $c) {
            $code = $this->appendCode($code, $c);
        }
        $this->prefix_code = array();
        return $code;
    }

}
