Improve component attach UX

pages/components.php

@@ -15,19 +15,26 @@ if (!$user->hasPermission("MACHINEMANAGER_VIEW")) {
 
 $writeaccess = $user->hasPermission("MACHINEMANAGER_EDIT");
 
-$components = $database->select("components", ["compid", "serial", "machineid", "model", "manufacturer", "capacity"]);
-
 $attachto = false;
 if (!empty($VARS["attachto"]) && Machine::exists($VARS["attachto"])) {
     $attachto = $VARS["attachto"];
+    $components = $database->select("components", ["compid", "serial", "machineid", "model", "manufacturer", "capacity"], ["machineid" => null]);
+} else {
+    $components = $database->select("components", ["compid", "serial", "machineid", "model", "manufacturer", "capacity"]);
 }
 ?>
 
-<div class="btn-group">
-    <?php if ($writeaccess) { ?>
-        <a href="app.php?page=editcomponent" class="btn btn-success"><i class="fas fa-plus"></i> <?php $Strings->get("Add Component"); ?></a>
-    <?php } ?>
-</div>
+<?php if ($attachto != false) { ?>
+    <div class="alert alert-info" role="alert">
+        Select an unused component to attach to machine #<?php echo htmlspecialchars($VARS["attachto"]); ?>
+    </div>
+<?php } else { ?>
+    <div class="btn-group">
+        <?php if ($writeaccess) { ?>
+            <a href="app.php?page=editcomponent" class="btn btn-success"><i class="fas fa-plus"></i> <?php $Strings->get("Add Component"); ?></a>
+        <?php } ?>
+    </div>
+<?php } ?>
 <table id="componenttable" class="table table-bordered table-hover table-sm">
     <thead>
         <tr>