- ReqHandler added

- interface reworked

class/ReqHandler.php

@@ -0,0 +1,139 @@
+<?php
+
+
+// response types
+const RESP_NONE = "none";
+const RESP_PLAIN = "plain";
+const RESP_JSON = "json";
+
+// Request Handler Assignment class
+// Members get populated when instantiated by ReqHandler;
+// should not be used outside ReqHandler
+class ReqHandlerAssignment
+{
+    // members
+    public string $action; // action string
+    public array $params; // request parameters
+    public string $handler; // handler function
+    public string $hint; // human-readable hint about what this action performs
+    public string $level; // required command authentication level
+    public string $resp_type; // response type
+    public ReqHandler $rh; // reference to request handler
+
+    function __construct(string $action, array $params, string $level, string $handler, string $resp_type, string $hint, ReqHandler &$rh)
+    {
+        $this->action = $action;
+        $this->params = $params;
+        $this->level = $level;
+        $this->handler = $handler;
+        $this->resp_type = $resp_type;
+        $this->hint = $hint;
+        $this->rh = &$rh; // assign be reference
+    }
+}
+
+// Request Handler class
+class ReqHandler
+{
+    private array $mapping; // action-handler mapping
+    private array $request; // reference to $_REQUEST
+    private array $files; // reference to $_FILES
+    private string $level; // max privilege level
+
+    // Constructor
+    function __construct()
+    {
+        // create reference bindings
+        $this->request = &$_REQUEST;
+        $this->files = &$_FILES;
+
+        $this->mapping = [PRIVILEGE_NONE => [], PRIVILEGE_PLAYER => [], PRIVILEGE_CREATOR => [], PRIVILEGE_QUIZMASTER => []]; // create assignment categories
+        $this->level = PRIVILEGE_NONE;
+    }
+
+    // Add new handler
+    function add(string|array $actions, array $params, string $level, string $handler, string $resp_type, string $hint): bool
+    {
+        // convert single actions to array
+        $actions = is_string($actions) ? [$actions] : $actions;
+
+        // cannot assign more than one handler to the same action
+        foreach ($actions as $action) {
+            if (in_array($action, $this->mapping[$level])) {
+                return false;
+            }
+
+            // create the assignment object
+            $assignment = new ReqHandlerAssignment($action, $params, $level, $handler, $resp_type, $hint, $this);
+            $this->mapping[$level][$action] = $assignment;
+        }
+
+        return true;
+    }
+
+    const ACTION_KEY = "action";
+
+    // Process possible pending request. Also check access privilege.
+    function process(string $level = null, string $action_key = self::ACTION_KEY) : array {
+        // get action
+        $action = $this->request[$action_key] ?? "";
+
+        // don't process empty actions
+        if (trim($action) === "") {
+            return ["", false];
+        }
+
+        // if privilege level is specified, then store
+        $this->level = $level ?? $this->level;
+
+        $resp = "";
+        $success = false;
+
+        // look up action
+        $categories = array_keys($this->mapping);
+        $highest_category_index = array_search($this->level, $categories);
+        for ($i = 0; ($i < count($categories)) && ($i <= $highest_category_index); $i++) {
+            // get category
+            $category = &$this->mapping[$categories[$i]];
+
+            // find the command level category that includes this action
+            if (array_key_exists($action, $category)) {
+                // get assignment
+                $assignment = &$category[$action];
+
+                // check that all required parameters were passed
+                $all_params_passed = true;
+                foreach ($assignment->params as $param) {
+                    $all_params_passed &= array_key_exists($param, $this->request);
+                }
+
+                // if params were provided, then invoke the callback
+                if ($all_params_passed) {
+                    $handler = $assignment->handler;
+                    $raw_resp = $handler($this, $this->request);
+
+                    // convert response to preset response type
+                    if ($assignment->resp_type !== RESP_NONE) { // if command returns with anything at all
+                        if ($assignment->resp_type === RESP_JSON) { // JSON
+                            $resp = json_encode($raw_resp);
+                        } else if ($assignment->resp_type === RESP_PLAIN) { // PLAIN
+                            $resp = $raw_resp;
+                        }
+                    }
+
+                    // processing successful
+                    $success = true;
+
+                    break; // break the loop
+                }
+            }
+        }
+
+        return [$resp, $success];
+    }
+
+    // Set access privilege level
+    function set_privilege_level(string $level) {
+        $this->level = $level;
+    }
+}

style/spreadquiz_mobile.css

@@ -38,6 +38,10 @@
         width: calc(100vw - 3em);
     }
 
+    section.answer label {
+        max-width: 80%;
+    }
+
     section#infobox {
         top: unset;
         left: 0;

usermgr.php

@@ -7,6 +7,7 @@ require_once "controller.php";
 
 $userdb = new \SleekDB\Store(USERDB, DATADIR, ["timeout" => false]);
 
+const PRIVILEGE_NONE = "none";
 const PRIVILEGE_PLAYER = "player";
 const PRIVILEGE_CREATOR = "creator";
 const PRIVILEGE_QUIZMASTER = "admin"; // TODO: refactor!