<?php
/***************************************************************************
 *                              template.php
 *                            -------------------
 *   begin                : Saturday, Feb 13, 2001
 *   copyright            : (C) 2001 The phpBB Group
 *   email                : support@phpbb.com
 *
 *   $Id: template.php,v 1.10.2.5 2005/05/06 20:50:11 acydburn Exp $
 *
 *
 ***************************************************************************/

/***************************************************************************
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 ***************************************************************************/

/**
 * Template class. By Nathan Codding of the phpBB group.
 * The interface was originally inspired by PHPLib templates,
 * and the template file formats are quite similar.
 *
 */

class Template {
        var $classname = "Template";

        // variable that holds all the data we'll be substituting into
        // the compiled templates.
        // ...
        // This will end up being a multi-dimensional array like this:
        // $this->_tpldata[block.][iteration#][child.][iteration#][child2.][iteration#][variablename] == value
        // if it's a root-level variable, it'll be like this:
        // $this->_tpldata[.][0][varname] == value
        var $_tpldata = array();

        // Hash of filenames for each template handle.
        var $files = array();

        // Root template directory.
        var $root = "";

        // this will hash handle names to the compiled code for that handle.
        var $compiled_code = array();

        // This will hold the uncompiled code for that handle.
        var $uncompiled_code = array();

        /**
         * Constructor. Simply sets the root dir.
         *
         */
        function Template($root = ".")
        {
                $this->set_rootdir($root);
        }

        /**
         * Destroys this template object. Should be called when you're done with it, in order
         * to clear out the template data so you can load/parse a new template set.
         */
        function destroy()
        {
                $this->_tpldata = array();
        }

        /**
         * Sets the template root directory for this Template object.
         */
        function set_rootdir($dir)
        {
                if (!is_dir($dir))
                {
                        return false;
                }

                $this->root = $dir;
                return true;
        }

        /**
         * Sets the template filenames for handles. $filename_array
         * should be a hash of handle => filename pairs.
         */
        function set_filenames($filename_array)
        {
                if (!is_array($filename_array))
                {
                        return false;
                }

                reset($filename_array);
                while(list($handle, $filename) = each($filename_array))
                {
                        $this->files[$handle] = $this->make_filename($filename);
                }

                return true;
        }


        /**
         * Load the file for the handle, compile the file,
         * and run the compiled code. This will print out
         * the results of executing the template.
         */
        function pparse($handle)
        {
                if (!$this->loadfile($handle))
                {
                        die("Template->pparse(): Couldn't load template file for handle $handle");
                }

                // actually compile the template now.
                if (!isset($this->compiled_code[$handle]) || empty($this->compiled_code[$handle]))
                {
                        // Actually compile the code now.
                        $this->compiled_code[$handle] = $this->compile($this->uncompiled_code[$handle]);
                }

                // Run the compiled code.
                eval($this->compiled_code[$handle]);
                return true;
        }

        /**
         * Inserts the uncompiled code for $handle as the
         * value of $varname in the root-level. This can be used
         * to effectively include a template in the middle of another
         * template.
         * Note that all desired assignments to the variables in $handle should be done
         * BEFORE calling this function.
         */
        function assign_var_from_handle($varname, $handle)
        {
                if (!$this->loadfile($handle))
                {
                        die("Template->assign_var_from_handle(): Couldn't load template file for handle $handle");
                }

                // Compile it, with the "no echo statements" option on.
                $_str = "";
                $code = $this->compile($this->uncompiled_code[$handle], true, '_str');

                // evaluate the variable assignment.
                eval($code);
                // assign the value of the generated variable to the given varname.
                $this->assign_var($varname, $_str);

                return true;
        }

        /**
         * Block-level variable assignment. Adds a new block iteration with the given
         * variable assignments. Note that this should only be called once per block
         * iteration.
         */
        function assign_block_vars($blockname, $vararray)
        {
                if (strstr($blockname, '.'))
                {
                        // Nested block.
                        $blocks = explode('.', $blockname);
                        $blockcount = sizeof($blocks) - 1;
                        $str = '$this->_tpldata';
                        for ($i = 0; $i < $blockcount; $i++)
                        {
                                $str .= '[\'' . $blocks[$i] . '.\']';
                                eval('$lastiteration = sizeof(' . $str . ') - 1;');
                                $str .= '[' . $lastiteration . ']';
                        }
                        // Now we add the block that we're actually assigning to.
                        // We're adding a new iteration to this block with the given
                        // variable assignments.
                        $str .= '[\'' . $blocks[$blockcount] . '.\'][] = $vararray;';

                        // Now we evaluate this assignment we've built up.
                        eval($str);
                }
                else
                {
                        // Top-level block.
                        // Add a new iteration to this block with the variable assignments
                        // we were given.
                        $this->_tpldata[$blockname . '.'][] = $vararray;
                }

                return true;
        }

        /**
         * Root-level variable assignment. Adds to current assignments, overriding
         * any existing variable assignment with the same name.
         */
        function assign_vars($vararray)
        {
                reset ($vararray);
                while (list($key, $val) = each($vararray))
                {
                        $this->_tpldata['.'][0][$key] = $val;
                }

                return true;
        }

        /**
         * Root-level variable assignment. Adds to current assignments, overriding
         * any existing variable assignment with the same name.
         */
        function assign_var($varname, $varval)
        {
                $this->_tpldata['.'][0][$varname] = $varval;

                return true;
        }


        /**
         * Generates a full path+filename for the given filename, which can either
         * be an absolute name, or a name relative to the rootdir for this Template
         * object.
         */
        function make_filename($filename)
        {
                // Check if it's an absolute or relative path.
                if (substr($filename, 0, 1) != '/')
                {
                $filename = ($rp_filename = phpbb_realpath($this->root . '/' . $filename)) ? $rp_filename : $filename;
                }

                if (!file_exists($filename))
                {
                        die("Template->make_filename(): Error - file $filename does not exist");
                }

                return $filename;
        }


        /**
         * If not already done, load the file for the given handle and populate
         * the uncompiled_code[] hash with its code. Do not compile.
         */
        function loadfile($handle)
        {
                // If the file for this handle is already loaded and compiled, do nothing.
                if (isset($this->uncompiled_code[$handle]) && !empty($this->uncompiled_code[$handle]))
                {
                        return true;
                }

                // If we don't have a file assigned to this handle, die.
                if (!isset($this->files[$handle]))
                {
                        die("Template->loadfile(): No file specified for handle $handle");
                }

                $filename = $this->files[$handle];

                $str = implode("", @file($filename));
                if (empty($str))
                {
                        die("Template->loadfile(): File $filename for handle $handle is empty");
                }

                $this->uncompiled_code[$handle] = $str;

                return true;
        }



        /**
         * Compiles the given string of code, and returns
         * the result in a string.
         * If "do_not_echo" is true, the returned code will not be directly
         * executable, but can be used as part of a variable assignment
         * for use in assign_code_from_handle().
         */
        function compile($code, $do_not_echo = false, $retvar = '')
        {
                // replace \ with \\ and then ' with \'.
                $code = str_replace('\\', '\\\\', $code);
                $code = str_replace('\'', '\\\'', $code);

                // change template varrefs into PHP varrefs

                // This one will handle varrefs WITH namespaces
                $varrefs = array();
                preg_match_all('#\{(([a-z0-9\-_]+?\.)+?)([a-z0-9\-_]+?)\}#is', $code, $varrefs);
                $varcount = sizeof($varrefs[1]);
                for ($i = 0; $i < $varcount; $i++)
                {
                        $namespace = $varrefs[1][$i];
                        $varname = $varrefs[3][$i];
                        $new = $this->generate_block_varref($namespace, $varname);

                        $code = str_replace($varrefs[0][$i], $new, $code);
                }

                // This will handle the remaining root-level varrefs
                $code = preg_replace('#\{([a-z0-9\-_]*?)\}#is', '\' . ( ( isset($this->_tpldata[\'.\'][0][\'\1\']) ) ? $this->_tpldata[\'.\'][0][\'\1\'] : \'\' ) . \'', $code);

                // Break it up into lines.
                $code_lines = explode("\n", $code);

                $block_nesting_level = 0;
                $block_names = array();
                $block_names[0] = ".";

                // Second: prepend echo ', append ' . "\n"; to each line.
                $line_count = sizeof($code_lines);
                for ($i = 0; $i < $line_count; $i++)
                {
                        $code_lines[$i] = chop($code_lines[$i]);
                        if (preg_match('#<!-- BEGIN (.*?) -->#', $code_lines[$i], $m))
                        {
                                $n[0] = $m[0];
                                $n[1] = $m[1];

                                // Added: dougk_ff7-Keeps templates from bombing if begin is on the same line as end.. I think. :)
                                if ( preg_match('#<!-- END (.*?) -->#', $code_lines[$i], $n) )
                                {
                                        $block_nesting_level++;
                                        $block_names[$block_nesting_level] = $m[1];
                                        if ($block_nesting_level < 2)
                                        {
                                                // Block is not nested.
                                                $code_lines[$i] = '$_' . $n[1] . '_count = ( isset($this->_tpldata[\'' . $n[1] . '.\']) ) ?  sizeof($this->_tpldata[\'' . $n[1] . '.\']) : 0;';
                                                $code_lines[$i] .= "\n" . 'for ($_' . $n[1] . '_i = 0; $_' . $n[1] . '_i < $_' . $n[1] . '_count; $_' . $n[1] . '_i++)';
                                                $code_lines[$i] .= "\n" . '{';
                                        }
                                        else
                                        {
                                                // This block is nested.

                                                // Generate a namespace string for this block.
                                                $namespace = implode('.', $block_names);
                                                // strip leading period from root level..
                                                $namespace = substr($namespace, 2);
                                                // Get a reference to the data array for this block that depends on the
                                                // current indices of all parent blocks.
                                                $varref = $this->generate_block_data_ref($namespace, false);
                                                // Create the for loop code to iterate over this block.
                                                $code_lines[$i] = '$_' . $n[1] . '_count = ( isset(' . $varref . ') ) ? sizeof(' . $varref . ') : 0;';
                                                $code_lines[$i] .= "\n" . 'for ($_' . $n[1] . '_i = 0; $_' . $n[1] . '_i < $_' . $n[1] . '_count; $_' . $n[1] . '_i++)';
                                                $code_lines[$i] .= "\n" . '{';
                                        }

                                        // We have the end of a block.
                                        unset($block_names[$block_nesting_level]);
                                        $block_nesting_level--;
                                        $code_lines[$i] .= '} // END ' . $n[1];
                                        $m[0] = $n[0];
                                        $m[1] = $n[1];
                                }
                                else
                                {
                                        // We have the start of a block.
                                        $block_nesting_level++;
                                        $block_names[$block_nesting_level] = $m[1];
                                        if ($block_nesting_level < 2)
                                        {
                                                // Block is not nested.
                                                $code_lines[$i] = '$_' . $m[1] . '_count = ( isset($this->_tpldata[\'' . $m[1] . '.\']) ) ? sizeof($this->_tpldata[\'' . $m[1] . '.\']) : 0;';
                                                $code_lines[$i] .= "\n" . 'for ($_' . $m[1] . '_i = 0; $_' . $m[1] . '_i < $_' . $m[1] . '_count; $_' . $m[1] . '_i++)';
                                                $code_lines[$i] .= "\n" . '{';
                                        }
                                        else
                                        {
                                                // This block is nested.

                                                // Generate a namespace string for this block.
                                                $namespace = implode('.', $block_names);
                                                // strip leading period from root level..
                                                $namespace = substr($namespace, 2);
                                                // Get a reference to the data array for this block that depends on the
                                                // current indices of all parent blocks.
                                                $varref = $this->generate_block_data_ref($namespace, false);
                                                // Create the for loop code to iterate over this block.
                                                $code_lines[$i] = '$_' . $m[1] . '_count = ( isset(' . $varref . ') ) ? sizeof(' . $varref . ') : 0;';
                                                $code_lines[$i] .= "\n" . 'for ($_' . $m[1] . '_i = 0; $_' . $m[1] . '_i < $_' . $m[1] . '_count; $_' . $m[1] . '_i++)';
                                                $code_lines[$i] .= "\n" . '{';
                                        }
                                }
                        }
                        else if (preg_match('#<!-- END (.*?) -->#', $code_lines[$i], $m))
                        {
                                // We have the end of a block.
                                unset($block_names[$block_nesting_level]);
                                $block_nesting_level--;
                                $code_lines[$i] = '} // END ' . $m[1];
                        }
                        else
                        {
                                // We have an ordinary line of code.
                                if (!$do_not_echo)
                                {
                                        $code_lines[$i] = 'echo \'' . $code_lines[$i] . '\' . "\\n";';
                                }
                                else
                                {
                                        $code_lines[$i] = '$' . $retvar . '.= \'' . $code_lines[$i] . '\' . "\\n";'; 
                                }
                        }
                }

                // Bring it back into a single string of lines of code.
                $code = implode("\n", $code_lines);
                return $code    ;

        }


        /**
         * Generates a reference to the given variable inside the given (possibly nested)
         * block namespace. This is a string of the form:
         * ' . $this->_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['varname'] . '
         * It's ready to be inserted into an "echo" line in one of the templates.
         * NOTE: expects a trailing "." on the namespace.
         */
        function generate_block_varref($namespace, $varname)
        {
                // Strip the trailing period.
                $namespace = substr($namespace, 0, strlen($namespace) - 1);

                // Get a reference to the data block for this namespace.
                $varref = $this->generate_block_data_ref($namespace, true);
                // Prepend the necessary code to stick this in an echo line.

                // Append the variable reference.
                $varref .= '[\'' . $varname . '\']';

                $varref = '\' . ( ( isset(' . $varref . ') ) ? ' . $varref . ' : \'\' ) . \'';

                return $varref;

        }


        /**
         * Generates a reference to the array of data values for the given
         * (possibly nested) block namespace. This is a string of the form:
         * $this->_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['$childN']
         *
         * If $include_last_iterator is true, then [$_childN_i] will be appended to the form shown above.
         * NOTE: does not expect a trailing "." on the blockname.
         */
        function generate_block_data_ref($blockname, $include_last_iterator)
        {
                // Get an array of the blocks involved.
                $blocks = explode(".", $blockname);
                $blockcount = sizeof($blocks) - 1;
                $varref = '$this->_tpldata';
                // Build up the string with everything but the last child.
                for ($i = 0; $i < $blockcount; $i++)
                {
                        $varref .= '[\'' . $blocks[$i] . '.\'][$_' . $blocks[$i] . '_i]';
                }
                // Add the block reference for the last child.
                $varref .= '[\'' . $blocks[$blockcount] . '.\']';
                // Add the iterator for the last child if requried.
                if ($include_last_iterator)
                {
                        $varref .= '[$_' . $blocks[$blockcount] . '_i]';
                }

                return $varref;
        }

}

?>