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<?php
/*
Plugin Name: BuddyPress Search Default
Plugin URI: https://gist.github.com/5805248
Description: Default search select is posts. Search on home URL for custom posts URL.
Author: Josef Jezek
Author URI: http://about.me/josefjezek
Version: 0.2
*/

// Default search select is posts.
add_filter( 'bp_search_form_type_select_options', 'jj_search_default', 10, 1);

function jj_search_default($options) {
  $newoptions = array();
  $newoptions['posts'] = $options['posts'];
  
  foreach( (array) $options as $option_value => $option_title ) {
    if ( $option_value != 'posts' ) {
      $newoptions[$option_value] = $option_title;
    }
  }
  
  return $newoptions;
}

// Search on home URL for custom posts URL.
add_filter( 'bp_core_search_site', 'jj_search_on_home_url', 10, 1);

function jj_search_on_home_url($url) {
  $search_which = !empty( $_POST['search-which'] ) ? $_POST['search-which'] : '';

  if ( $search_which == 'posts' ) {
    $search_terms = stripslashes( $_POST['search-terms'] );
    $query_string = '/?s=';

    return home_url( $query_string . urlencode( $search_terms ) );
  }

  return $url;
}
?>