Fix #11554: Status legend should react to current filter settings

The status legend shown at the bottom of the view all issues page should
factor in the current filter settings.

The following conditions should apply to showing the status legend:
* Don't show the legend if there is only one status selected by the
  filter
* Hide statuses from the legend that are hidden by the 'hide status'
  filter (for simple filters)
* Hide statuses from the legend that aren't selected using an advanced
  status filter

core/html_api.php

@@ -66,6 +66,8 @@
  * @uses error_api.php
  * @uses event_api.php
  * @uses file_api.php
+ * @uses filter_api.php
+ * @uses filter_constants_inc.php
  * @uses form_api.php
  * @uses helper_api.php
  * @uses lang_api.php
@@ -89,6 +91,8 @@
 require_api( 'error_api.php' );
 require_api( 'event_api.php' );
 require_api( 'file_api.php' );
+require_api( 'filter_api.php' );
+require_api( 'filter_constants_inc.php' );
 require_api( 'form_api.php' );
 require_api( 'helper_api.php' );
 require_api( 'lang_api.php' );
@@ -1219,6 +1223,15 @@ function html_status_legend() {
 	echo '<table class="width100" cellspacing="1">';
 	echo '<tr>';
 
+	# Don't show the legend if only one status is selected by the current filter
+	$t_current_filter = current_user_get_bug_filter();
+	$t_simple_filter = $t_current_filter['_view_type'] == 'simple';
+	if( $t_simple_filter ) {
+		if( !filter_field_is_any( $t_current_filter[FILTER_PROPERTY_STATUS_ID][0] ) ) {
+			return null;
+		}
+	}
+
 	$t_status_array = MantisEnum::getAssocArrayIndexedByValues( config_get( 'status_enum_string' ) );
 	$t_status_names = MantisEnum::getAssocArrayIndexedByValues( lang_get( 'status_enum_string' ) );
 	$enum_count = count( $t_status_array );
@@ -1236,6 +1249,27 @@ function html_status_legend() {
 		}
 	}
 
+	# Remove status values that won't appear as a result of the current filter
+	foreach( $t_status_array as $t_status => $t_name ) {
+		if( $t_simple_filter ) {
+			if( !filter_field_is_none( $t_current_filter[FILTER_PROPERTY_HIDE_STATUS_ID][0] ) &&
+				$t_status >= $t_current_filter[FILTER_PROPERTY_HIDE_STATUS_ID][0] ) {
+				unset( $t_status_array[$t_status] );
+			}
+		} else {
+			if( !in_array( META_FILTER_ANY, $t_current_filter[FILTER_PROPERTY_STATUS_ID] ) &&
+				!in_array( $t_status, $t_current_filter[FILTER_PROPERTY_STATUS_ID] ) ) {
+				unset( $t_status_array[$t_status] );
+			}
+		}
+	}
+
+	# If there aren't at least two statuses showable by the current filter,
+	# don't draw the status bar
+	if( count( $t_status_array ) <= 1 ) {
+		return null;
+	}
+
 	# draw the status bar
 	$width = (int)( 100 / count( $t_status_array ) );
 	foreach( $t_status_array as $t_status => $t_name ) {