<?php

/**
 * Project: 
 * Contenido Content Management System
 * 
 * Description: 
 * 
 * Requirements: 
 * @con_php_req 5
 * 
 *
 * @package    ContenidoBackendArea
 * @version    0.2
 * @author     unknown
 * @copyright  four for business AG <www.4fb.de>
 * @license    http://www.contenido.org/license/LIZENZ.txt
 * @link       http://www.4fb.de
 * @link       http://www.contenido.org
 * 
 * 
 * 
 * {@internal 
 *   created  unknown
 *   modified 2008-07-07, bilal arslan, added security fix
 *
 *   $Id$:
 * }}
 * 
 */
if (!defined('CON_FRAMEWORK')) {
    die('Illegal call');
}

function injectSQL(&$db, $prefix, $file, &$failedChunks, $replacements = []) {
    $file = trim($file);

    if (!isReadable($file)) {
        return false;
    }

    $sqlFile = file_get_contents($file);

    $sqlFile = remove_comments($sqlFile);
    $sqlFile = remove_remarks($sqlFile);
    $sqlFile = str_replace("!PREFIX!", $prefix, $sqlFile);
    $sqlFile = trim($sqlFile);

    $sqlChunks = split_sql_file(trim($sqlFile), ";");

    foreach ($sqlChunks as $sqlChunk) {
        foreach ($replacements as $find => $replace) {
            $sqlChunk = str_replace($find, $replace, $sqlChunk);
        }

        $db->query($sqlChunk);

        if ($db->Errno != 0) {
            $failedChunks[] = ["sql" => $sqlChunk, "errno" => $db->Errno, "error" => $db->Error];
        }
    }

    return true;
}

//
// remove_comments will strip the sql comment lines out of an uploaded sql file
// specifically for mssql and postgres type files in the install....
//
function remove_comments(&$output) {
    $lines = explode("\n", $output);
    $output = "";

    // try to keep mem. use down
    $linecount = count($lines);

    $in_comment = false;
    for ($i = 0; $i < $linecount; $i++) {
        if (preg_match("/^\/\*/", preg_quote($lines[$i]))) {
            $in_comment = true;
        }

        if (!$in_comment) {
            $output .= $lines[$i] . "\n";
        }

        if (preg_match("/\*\/$/", preg_quote($lines[$i]))) {
            $in_comment = false;
        }
    }

    unset($lines);
    return $output;
}

//
// remove_remarks will strip the sql comment lines out of an uploaded sql file
//
function remove_remarks($sql) {
    $lines = explode("\n", $sql);

    // try to keep mem. use down
    $sql = "";

    $linecount = count($lines);
    $output = "";

    for ($i = 0; $i < $linecount; $i++) {
        if (($i != ($linecount - 1)) || (strlen($lines[$i]) > 0)) {
            if (!empty($lines[$i][0]) && $lines[$i][0] != "#") {
                $output .= $lines[$i] . "\n";
            } else {
                $output .= "\n";
            }
            // Trading a bit of speed for lower mem. use here.
            $lines[$i] = "";
        }
    }

    return $output;
}

//
// split_sql_file will split an uploaded sql file into single sql statements.
// Note: expects trim() to have already been run on $sql.
//
function split_sql_file($sql, $delimiter) {
    // Split up our string into "possible" SQL statements.
    $tokens = explode($delimiter, $sql);

    // try to save mem.
    $sql = "";
    $output = [];

    // we don't actually care about the matches preg gives us.
    $matches = [];

    // this is faster than calling count($oktens) every time thru the loop.
    $token_count = count($tokens);
    for ($i = 0; $i < $token_count; $i++) {
        // Don't wanna add an empty string as the last thing in the array.
        if (($i != ($token_count - 1)) || (strlen($tokens[$i] > 0))) {
            // This is the total number of single quotes in the token.
            $total_quotes = preg_match_all("/'/", $tokens[$i], $matches);
            // Counts single quotes that are preceded by an odd number of backslashes, 
            // which means they're escaped quotes.
            $escaped_quotes = preg_match_all("/(?<!\\\\)(\\\\\\\\)*\\\\'/", $tokens[$i], $matches);

            $unescaped_quotes = $total_quotes - $escaped_quotes;

            // If the number of unescaped quotes is even, then the delimiter did NOT occur inside a string literal.
            if (($unescaped_quotes % 2) == 0) {
                // It's a complete sql statement.
                $output[] = $tokens[$i];
                // save memory.
                $tokens[$i] = "";
            } else {
                // incomplete sql statement. keep adding tokens until we have a complete one.
                // $temp will hold what we have so far.
                $temp = $tokens[$i] . $delimiter;
                // save memory..
                $tokens[$i] = "";

                // Do we have a complete statement yet? 
                $complete_stmt = false;

                for ($j = $i + 1; (!$complete_stmt && ($j < $token_count)); $j++) {
                    // This is the total number of single quotes in the token.
                    $total_quotes = preg_match_all("/'/", $tokens[$j], $matches);
                    // Counts single quotes that are preceded by an odd number of backslashes, 
                    // which means they're escaped quotes.
                    $escaped_quotes = preg_match_all("/(?<!\\\\)(\\\\\\\\)*\\\\'/", $tokens[$j], $matches);

                    $unescaped_quotes = $total_quotes - $escaped_quotes;

                    if (($unescaped_quotes % 2) == 1) {
                        // odd number of unescaped quotes. In combination with the previous incomplete
                        // statement(s), we now have a complete statement. (2 odds always make an even)
                        $output[] = $temp . $tokens[$j];

                        // save memory.
                        $tokens[$j] = "";
                        $temp = "";

                        // exit the loop.
                        $complete_stmt = true;
                        // make sure the outer loop continues at the right point.
                        $i = $j;
                    } else {
                        // even number of unescaped quotes. We still don't have a complete statement. 
                        // (1 odd and 1 even always make an odd)
                        $temp .= $tokens[$j] . $delimiter;
                        // save memory.
                        $tokens[$j] = "";
                    }
                } // for..
            } // else
        }
    }

    return $output;
}

?>
