Fix various compatibility issues with PHP 8

libs/ical/Component.php

@@ -0,0 +1,184 @@
+<?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;
+
+use Eluceo\iCal\Util\ComponentUtil;
+
+/**
+ * Abstract Calender Component.
+ */
+abstract class Component
+{
+    /**
+     * Array of Components.
+     *
+     * @var Component[]
+     */
+    protected $components = [];
+
+    /**
+     * The order in which the components will be rendered during build.
+     *
+     * Not defined components will be appended at the end.
+     *
+     * @var array
+     */
+    private $componentsBuildOrder = ['VTIMEZONE', 'DAYLIGHT', 'STANDARD'];
+
+    /**
+     * The type of the concrete Component.
+     *
+     * @abstract
+     *
+     * @return string
+     */
+    abstract public function getType();
+
+    /**
+     * Building the PropertyBag.
+     *
+     * @abstract
+     *
+     * @return PropertyBag
+     */
+    abstract public function buildPropertyBag();
+
+    /**
+     * Adds a Component.
+     *
+     * If $key is given, the component at $key will be replaced else the component will be append.
+     *
+     * @param Component $component The Component that will be added
+     * @param null      $key       The key of the Component
+     */
+    public function addComponent(self $component, $key = null)
+    {
+        if (null == $key) {
+            $this->components[] = $component;
+        } else {
+            $this->components[$key] = $component;
+        }
+    }
+
+    /**
+     * Set all Components.
+     *
+     * @param Component[] $components The array of Component that will be set
+     * @param null        $key        The key of the Component
+     */
+    public function setComponents(array $components)
+    {
+        $this->components = $components;
+
+        return $this;
+    }
+
+    /**
+     * Renders an array containing the lines of the iCal file.
+     *
+     * @return array
+     */
+    public function build()
+    {
+        $lines = [];
+
+        $lines[] = sprintf('BEGIN:%s', $this->getType());
+
+        /** @var $property Property */
+        foreach ($this->buildPropertyBag() as $property) {
+            foreach ($property->toLines() as $l) {
+                $lines[] = $l;
+            }
+        }
+
+        $this->buildComponents($lines);
+
+        $lines[] = sprintf('END:%s', $this->getType());
+
+        $ret = [];
+
+        foreach ($lines as $line) {
+            foreach (ComponentUtil::fold($line) as $l) {
+                $ret[] = $l;
+            }
+        }
+
+        return $ret;
+    }
+
+    /**
+     * Renders the output.
+     *
+     * @return string
+     */
+    public function render()
+    {
+        return implode("\r\n", $this->build());
+    }
+
+    /**
+     * Renders the output when treating the class as a string.
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->render();
+    }
+
+    /**
+     * @param $lines
+     *
+     * @return array
+     */
+    private function buildComponents(array &$lines)
+    {
+        $componentsByType = [];
+
+        /** @var $component Component */
+        foreach ($this->components as $component) {
+            $type = $component->getType();
+            if (!isset($componentsByType[$type])) {
+                $componentsByType[$type] = [];
+            }
+            $componentsByType[$type][] = $component;
+        }
+
+        // render ordered components
+        foreach ($this->componentsBuildOrder as $type) {
+            if (!isset($componentsByType[$type])) {
+                continue;
+            }
+            foreach ($componentsByType[$type] as $component) {
+                $this->addComponentLines($lines, $component);
+            }
+            unset($componentsByType[$type]);
+        }
+
+        // render all other
+        foreach ($componentsByType as $components) {
+            foreach ($components as $component) {
+                $this->addComponentLines($lines, $component);
+            }
+        }
+    }
+
+    /**
+     * @param Component $component
+     */
+    private function addComponentLines(array &$lines, self $component)
+    {
+        foreach ($component->build() as $l) {
+            $lines[] = $l;
+        }
+    }
+}