Help with adding a conditional clause to mysql queries

I'm trying to tweak to the PHPmotion script (http://demo.phpmotiontemplates.com/default/)
to add another category to search.
I was told to do this:
1. Capture the category $_GET and $_POST values. Look through the top of search.php file,
and you can see how the keyword is retrieved and stored in a variable -
the "keyword"/"keywords" variables - you can do the same for your category".
2. After you've done that, you can do a check to see whether a category value was passed, and if so,
add an extra WHERE clause in the mysql queries in search.php to check based on the category value that was passed."

After someone else read that they said this:
"The way I understand it, they want you to see if the $keyword and $keywords variables are empty to see if any category was passed or requested.
You're already doing that by capturing the GET variable in
$keywords = $_GET['keyword'];
$keywords = str_replace(''s', "", $keywords)
The second line is just to replace single quotes with nothing.
Of course, if the variable is not empty is because someone passed a category and therefore in your query string you'll need to add
"WHERE category= '$keywords' "
I am assuming that the name of the field is category"

I've done some coding, but these instructions and are bit beyond my skill level.
A line of code example, would be helpful.
Any additional guidance or interpretation of these instructions will be appreciated.
Much thanks

<?php
error_reporting(0);
include_once ('classes/config.php');
include_once ('classes/sessions.php');

$default_album_pic = $config['default_album_pic'];

///////////////////////////////////////////////////////////////////////////////////////
// changed search server method to get to get rid of cache expired error

if( ( $_SERVER['REQUEST_METHOD'] != 'GET') ) dieNice();

$queryString = strtolower($_SERVER['QUERY_STRING']);
if (strstr($queryString,'%20union%20') OR strstr($queryString,'/*')) dieNice();

$referer    = mysql_real_escape_string( $_SERVER['HTTP_REFERER'] );
if ( $referer == '' ) dieNice();
if ( !ereg ($_SERVER['SERVER_NAME'], $referer) ) $flag_stop++;
if ( !ereg ($base_url, $referer) ) $flag_stop++;
if ( $flag_stop == 2 ) dieNice();

$keywords    = $_GET['keyword'];
$keywords    = str_replace('&#039;s', "", $keywords);

$debug_log_file = 'logs/search_log.txt';

if (@file_exists($debug_log_file)) {
    $fo = @fopen($debug_log_file, 'a');
         @fwrite($fo, $keywords);
         @fclose($fo);

} else {
         $fo = @fopen($debug_log_file, 'w');
         @fwrite($fo, $keywords);
         @fclose($fo);
}

$keyword     = mysql_real_escape_string($keywords);
$type     = mysql_real_escape_string( $_GET['type'] );

if ($type == '') {
    $keyword    = mysql_real_escape_string($keywords);
        $type        = mysql_real_escape_string($_GET['type']);
}

if ($keyword == '' | $type == '' ) {
    $type        = 'videos';
    $keyword     = 'none';
}


$get_type        = $type;

switch ( $get_type ) {

    case 'videos';
        $type_videos    = 1;
        $row_id        = 'video_id';
        $media_comments    = 'videocomments';
        $type_query_rows     = 'indexer, video_id, title, title_seo, date_uploaded, user_id, video_length, approved, public_private, description, tags, number_of_views';
    break;

     case 'audios';
        $type_audios     = 2;
        $row_id        = 'audio_id';
        $media_comments    = 'audiocomments';
        $type_query_rows     = 'indexer, audio_id, title, title_seo, date_uploaded, user_id, audio_length, approved, public_private, description, tags, number_of_views';
    break;

    case 'images';
        $type_images    = 3;
        $row_id        = 'image_id';
        $media_comments    = 'imagecomments';
        $type_query_rows     = 'indexer, image_id, gallery_id, title, title_seo, date_uploaded, user_id, approved, public_private, description, tags, number_of_views';
    break;

    case 'groups';
        //$type_groups    = 4;
        $row_id        = 'group_id';
        $media_comments    = 'groupcomments';
        $type_query_rows     = 'group_name, group_name_seo, public_private, todays_date, group_description, indexer, featured';

    break;

    case 'blogs';
        $type_blogs        = 5;
        $row_id         = 'blog_id';
        $media_comments    = 'blog_replys';
        $type_query_rows     = 'indexer, blog_owner, user_id, title, title_seo, description, tags, category, date_created, approved, number_of_views';
    break;
}

$query_get_type    = $get_type;

if ( $query_get_type == 'groups' ) {

    $query_get_type = 'group_profile';

    $page_guery        = "SELECT indexer FROM $query_get_type WHERE (group_name like '%$keyword%' or group_description like '%$keyword%')";
    $search_query    = "SELECT $type_query_rows FROM $query_get_type WHERE (group_name like '%$keyword%' or group_description like '%$keyword%') LIMIT "; // $set_limit, $limit";

} else {
    $tag_cloud         = make_tag_cloud( $get_type );
    $tag_cloud_block     = $tag_cloud[1];

    $page_guery        = "SELECT indexer FROM $query_get_type WHERE approved = 'yes' AND public_private = 'public' and (title like '%$keyword%' or tags like '%$keyword%' or description like '%$keyword%')";
    $search_query    = "SELECT $type_query_rows FROM $query_get_type WHERE approved = 'yes' AND public_private = 'public' and (title like '%$keyword%' or tags like '%$keyword%' or description like '%$keyword%') LIMIT "; // $set_limit, $limit";
}

if ( $query_get_type == 'group_profile' ) {

        $limit        = (int) mysql_real_escape_string( $config['search_page_limits'] );
        $pagination     = pagination($page_guery, $limit);
        $set_limit        = $pagination[0]['set_limit'];
        $total_pages    = $pagination[0]['total_pages'];
        $current_page     = $pagination[0]['current_page'];
        $total_records     = $pagination[0]['total_records'];
        $next_page         = $pagination[0]['next_page'];
        $prev_page         = $pagination[0]['prev_page'];
        $nl             = $pagination[0]['nl'];
        $pl             = $pagination[0]['pl'];

        $results_of     = $current_page * $limit;
        $results_show     = $set_limit + 1;

        if ( $results_of > $total_records )    $results_of = $total_records;
        if ( $set_limit == 0 )             $results_show = 1;
        if ( $total_records == 0 )         $results_show = 0;

     //define($get_type, true);

     // TODO //
     /*
     add group rating to search display
     re-write the 3 queries below using 1 JOIN query
     */
     // END //

    $sql            = $search_query . $set_limit .','. $limit;
    $query         = @mysql_query($sql);

    while ($result = @mysql_fetch_array($query)) {

            $group_id            = $result['indexer'];
            $sql2             = "SELECT indexer, video_id FROM group_videos WHERE group_id = $group_id AND video_status = 'active'";
            $query2             = @mysql_query($sql2);
            $count_group_videos     = @mysql_num_rows($query2);

            //get group video thumbnail
            if ($count_group_videos == 0) {

                $video_picture    = 'default_no_group_video';
                $group_video_id     = 0;

            } else {

                $result2             = @mysql_fetch_array($query2);
                $group_video_id         = mysql_real_escape_string($result2['video_id']);
                $sql0             = "SELECT indexer, video_id FROM videos WHERE indexer = $group_video_id";
                $query0            = @mysql_query($sql0);
                $result0             = @mysql_fetch_array($query0);
                $group_video_image    = $result0['video_id'];
                $video_picture         = $result0['video_id'];
                $group_video_id         = $result0['indexer'];
            }

            $video_array = array('video_picture'    => $video_picture,
                           'group_video_id'     => $group_video_id);

            $sql3                = "SELECT indexer FROM group_membership WHERE group_id = $group_id";
            $query3            = @mysql_query($sql3);
            $count_group_members     = @mysql_num_rows($query3);

            $sql4             = "SELECT member_username, member_id FROM group_membership WHERE group_id = $group_id AND group_admin = 'yes'";
            $query4             = @mysql_query($sql4);
            $result4             = @mysql_fetch_array($query4);
            $admin_username        = $result4['member_username'];

            $group_other_info     = array('group_videos'         => $count_group_videos,
                                    'group_members'     => $count_group_members,
                                    'admin_username'    => $admin_username);

            //merge arrays
            $group_array    = @array_merge($result, $group_other_info, $video_array);
            $mygroups[]     = $group_array;
        }
}

if ( $type == 'videos' || $type == 'audios' || $type == 'images' || $type == 'blogs'  ) {

    $limit        = (int) mysql_real_escape_string( $config['search_page_limits'] );
        $pagination     = pagination($page_guery, $limit);
        $set_limit        = $pagination[0]['set_limit'];
        $total_pages    = $pagination[0]['total_pages'];
        $current_page     = $pagination[0]['current_page'];
        $total_records     = $pagination[0]['total_records'];
        $next_page         = $pagination[0]['next_page'];
        $prev_page         = $pagination[0]['prev_page'];
        $nl             = $pagination[0]['nl'];
        $pl             = $pagination[0]['pl'];

        $result_search     = array();
        $sql            = $search_query . $set_limit .','. $limit;
        $query         = @mysql_query($sql);

        $results_of     = $current_page * $limit;
        $results_show     = $set_limit + 1;

        if ( $results_of > $total_records )    $results_of = $total_records;
        if ( $set_limit == 0 )             $results_show = 1;
        if ( $total_records == 0 )         $results_show = 0;

     define($get_type, true);

        while ($result1 = @mysql_fetch_array($query)) {

            $media_id        = mysql_real_escape_string($result1['indexer']);
            $sql2         = "SELECT indexer FROM $media_comments WHERE $row_id = $media_id";
           $query2         = @mysql_query($sql2);
            $comments_number    = @mysql_num_rows($query2);
            $comments_array     = array('comments' => $comments_number);

            $id            = $media_id;

            if ( $get_type == 'videos' ) {

                $stars_array = stars_array($media_id);
            } else {

                include ('stars_include.php');
                $stars_array    = array('star1' => $star1,'star2' => $star2,'star3' => $star3, 'star4' => $star4,'star5' => $star5);
            }

            // we need dynamic media image query
            $result_image    = $get_type;

            switch ( $result_image ) {

                case 'audios';
                    $pic_sql        = "SELECT album_picture FROM audio_albums WHERE album_id = '$media_id' LIMIT 1";
                $album_pic_result = @mysql_query($pic_sql);
                $row            = mysql_fetch_array( $album_pic_result );
                $album_pic_result = $row['album_picture'];
                if ( $album_pic_result != "" ) {
                    $album_pic = 'addons/audio/images/album_images/' . $album_pic_result;
                } else {
                    $album_pic = 'addons/audio/images/' . $default_album_pic;
                }
                $result_image_array    = array('media_image' => $album_pic);
            break;

            case 'images';
                    $full_view        = $result1['image_id'];
                    $full_url        = $config['site_base_url'] . '/addons/albums/images/'.$full_view;
                $result_image_array    = array('media_image' => $full_url);
            break;

            case 'blogs';

                $blog_owner    = $result1['user_id'];
                $a1_sql    = "SELECT file_name, approved FROM pictures WHERE user_id = $blog_owner";
                $a1_result    = @mysql_query($a1_sql);

                if (@mysql_num_rows($a1_result) != 0) {
                    $a1_result = @mysql_fetch_array($a1_result);
                    $a1_existing_file = $a1_result['file_name'];
                    $a1_approved = $a1_result['approved'];

                    if ($a1_approved == "yes") {
                        $poster_picture = $config['site_base_url'] . '/pictures/' . $a1_existing_file;
                    } else {
                        $poster_picture = $config['site_base_url'] . "/themes/$user_theme/images/placeholder.gif";
                    }
                } else {
                    $poster_picture = $config['site_base_url'] . "/themes/$user_theme/images/placeholder.gif";
                }

                $result_image_array    = array('media_image' => $poster_picture);
            break;

        } // end switch media images

        //merge arrays

             if ( sizeof($result_image_array) > 0 )
                 $result2    = @array_merge($result1, $comments_array, $stars_array, $result_image_array);
            else
                $result2    = @array_merge($result1, $comments_array, $stars_array);

            $result_search[]     = $result2;
        }

}

//PAGINATION PLUS
$url = 'search.php';
$additional_url_variable = "?keyword=$keyword&type=$type&page=";
include_once('includes/pagination.inc.php');
//PAGINATION PLUS >> end

// checking for any error codes
$codes = $_GET['code'];
$error_code = errorcodes($codes);

if (!empty($error_code)) {
    $blk_notification = $error_code['error_display'];
         $message_type = $error_code['error_type'];
         $error_message =$error_code['error_message'];
}

// create dynamic template words
$url_link        = $get_type;

if ( $url_link == 'images' ) $url_link = 'albums';
if ( $query_get_type == 'group_profile' ) {
    if ( $results_show == 0 ) $type_groups = '0'; else $type_groups = 4;
}

$get_type         = ucwords($get_type);
$get_type_word    = substr($get_type, 0, -1);
$page_title        = $config['site_name'] . ' ' . $get_type_word . ' ' . $lang_search . ' ' . $lang_results . ' ' . $lang_for . ' ' . $keyword;
$template        = "themes/$user_theme/templates/main_1.htm";
$inner_template1     = "themes/$user_theme/templates/search_results.htm";
$TBS            = new clsTinyButStrong;
$TBS->NoErr     = true;

$TBS->LoadTemplate("$template");

if ( $query_get_type == 'group_profile' ) $TBS->MergeBlock('blkfeatured', $mygroups); else $TBS->MergeBlock('blkfeatured', $result_search);

$TBS->Render = TBS_OUTPUT;
$TBS->Show();
@mysql_close();
die();

function dieNice() {
    header("Location: index.php");
    die();
}
?>

PHP:

 

I don't think I want to look through the code, just wanted to tell you that the code itself is... quite horrible, and very outdated. mysql_-functions, ereg being used... these are deprecated functions - same for suppressing any errors with @... this is a trainwreck, and should probably be avoided.
The code as it is today could probably also be condensed quite a bit, albeit, again, I haven't really looked into it very closely.

 

With all due respect, that's not very helpful

 

It's a suggestion that you find another plugin or theme that does what you want, as the current code is looking to be at least 5-6 years old (if not, it's just plain horrible).
Besides, hardcoding the video, audio and so forth values makes no sense - why not just pull them out of the DB to begin with (since you're matching against them, they have to be stored), and create a list based on that.

 

I want to write a more helpful reply here, but I have to agree with PoPSiCLe on this one! While that code can be modified to do what you want, you will struggle to find a one line cut-and-paste piece of code to fix your issues. You should either find a plugin that does what you want (hopefully a better coded one that is easier to work with and modify) or pay a PHP developer to modify it for you.