Fix various compatibility issues with PHP 8

libs/ical/ParameterBag.php

@@ -0,0 +1,107 @@
+<?php
+
+/*
+ * This file is part of the eluceo/iCal package.
+ *
+ * (c) Markus Poerschke <markus@eluceo.de>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+namespace Eluceo\iCal;
+
+class ParameterBag
+{
+    /**
+     * The params.
+     *
+     * @var array
+     */
+    protected $params;
+
+    public function __construct($params = [])
+    {
+        $this->params = $params;
+    }
+
+    /**
+     * @param string $name
+     * @param mixed  $value
+     */
+    public function setParam($name, $value)
+    {
+        $this->params[$name] = $value;
+    }
+
+    /**
+     * @param $name
+     *
+     * @return array|mixed
+     */
+    public function getParam($name)
+    {
+        if (isset($this->params[$name])) {
+            return $this->params[$name];
+        }
+
+        return null;
+    }
+
+    /**
+     * Checks if there are any params.
+     */
+    public function hasParams(): bool
+    {
+        return count($this->params) > 0;
+    }
+
+    public function toString(): string
+    {
+        $line = '';
+        foreach ($this->params as $param => $paramValues) {
+            if (!is_array($paramValues)) {
+                $paramValues = [$paramValues];
+            }
+            foreach ($paramValues as $k => $v) {
+                $paramValues[$k] = $this->escapeParamValue($v);
+            }
+
+            if ('' != $line) {
+                $line .= ';';
+            }
+
+            $line .= $param . '=' . implode(',', $paramValues);
+        }
+
+        return $line;
+    }
+
+    /**
+     * Returns an escaped string for a param value.
+     *
+     * @param string $value
+     *
+     * @return string
+     */
+    private function escapeParamValue($value)
+    {
+        $count = 0;
+        $value = str_replace('\\', '\\\\', $value);
+        $value = str_replace('"', '\"', $value, $count);
+        $value = str_replace("\n", '\\n', $value);
+        if (false !== strpos($value, ';') || false !== strpos($value, ',') || false !== strpos($value, ':') || $count) {
+            $value = '"' . $value . '"';
+        }
+
+        return $value;
+    }
+
+    /**
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->toString();
+    }
+}