commit 174e8090544c0d1925597cf59808ff9a0fb021a1
Author: Dirk Heilig <heilig@adesso-mobile.de>
Date:   Thu Apr 20 12:37:33 2023 +0200

    init

diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 0000000..d0fb3f2
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1 @@
+htdocs/vendor/*
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..acac0b5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+htdocs/cache/*
+htdocs/vendor/*
diff --git a/.prettierignore b/.prettierignore
new file mode 100644
index 0000000..6df1723
--- /dev/null
+++ b/.prettierignore
@@ -0,0 +1,3 @@
+htdocs/cache/*
+htdocs/vendor/*
+idea/*
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..1b29788
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,8 @@
+FROM php:8-apache
+RUN apt-get update && apt-get upgrade -y && apt-get install -y curl git unzip && rm -rf /var/lib/apt/lists/*
+RUN rm /var/www/html/* -rf
+RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
+COPY htdocs/ /var/www/html
+WORKDIR /var/www/html
+RUN composer install
+RUN chown www-data:www-data /var/www/html
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..7fbb274
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,16 @@
+.PHONY: install prettier
+
+prettier:
+	prettier -w .
+
+
+install: htdocs/vendor
+
+htdocs/vendor: htdocs/composer.json htdocs/composer.lock
+	cd htdocs ; composer install --no-dev --optimize-autoloader
+	touch htdocs/vendor
+
+htdocs/composer.lock: htdocs/composer.json
+	cd htdocs ; composer install --no-dev --optimize-autoloader
+	touch htdocs/composer.lock
+
diff --git a/htdocs/api/index.php b/htdocs/api/index.php
new file mode 100644
index 0000000..3b02027
--- /dev/null
+++ b/htdocs/api/index.php
@@ -0,0 +1,198 @@
+<?php
+header("Access-Control-Allow-Origin: *");
+use ICal\Event;
+use ICal\ICal;
+
+define("CACHE_DIR", "/tmp/app_data/cache");
+define("CACHE_TTL", 60 * 60);
+define("MAX_FILE_SIZE", 1024 * 1024 * 10);
+
+if (!isset($_REQUEST["url"])) {
+    header("HTTP/1.1 400 Bad Request");
+    echo "No url given";
+    exit();
+}
+$url = $_REQUEST["url"];
+$parsedUrl = parse_url($url);
+$host = $parsedUrl["host"];
+$hostIp = gethostbyname($host);
+if (
+    !filter_var(
+        $hostIp,
+        FILTER_VALIDATE_IP,
+        FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE
+    )
+) {
+    header("HTTP/1.1 400 Bad Request");
+    exit();
+}
+
+if (0 !== strpos($url, "http")) {
+    header("HTTP/1.1 400 Bad Request");
+    exit();
+}
+
+$start = isset($_REQUEST["start"]) ? $_REQUEST["start"] : "today";
+$end = isset($_REQUEST["end"]) ? $_REQUEST["end"] : "tomorrow";
+$maxItems = isset($_REQUEST["maxitems"]) ? intval($_REQUEST["maxitems"]) : 10;
+
+$completeCacheFile =
+    CACHE_DIR .
+    "/complete_" .
+    md5(json_encode([$url, $start, $end, $maxItems]));
+
+$start = strtotime($start);
+$end = strtotime($end);
+
+if (false === $start) {
+    header("HTTP/1.1 400 Bad Request");
+    echo "Start value is not a valid strtotime() parameter";
+    exit();
+}
+if (false === $end) {
+    header("HTTP/1.1 400 Bad Request");
+    echo "End value is not a valid strtotime() parameter";
+    exit();
+}
+if ($start > $end) {
+    header("HTTP/1.1 400 Bad Request");
+    echo "Start value is after end value";
+    exit();
+}
+
+if ($end - $start > 60 * 60 * 24 * 90) {
+    header("HTTP/1.1 400 Bad Request");
+    echo "Maximum range is 90 days";
+    exit();
+}
+if ($maxItems > 100) {
+    header("HTTP/1.1 400 Bad Request");
+    echo "Maximum number of items is 100";
+    exit();
+}
+
+header("X-Debug-used-url: $url");
+header("X-Debug-start: $start (" . date("Y-m-d", $start) . ")");
+header("X-Debug-end: $end (" . date("Y-m-d", $end) . ")");
+header("X-Debug-max-items: $maxItems");
+
+require_once __DIR__ . "/../vendor/autoload.php";
+
+if (!is_dir(CACHE_DIR)) {
+    mkdir(CACHE_DIR, 0777, true);
+}
+
+$urlCacheFile = CACHE_DIR . "/url_" . md5($url);
+header(
+    "X-Debug-Cache-File-data: " .
+        json_encode([$url, $start, $end, $maxItems], JSON_UNESCAPED_SLASHES)
+);
+if (
+    file_exists($completeCacheFile) &&
+    filemtime($completeCacheFile) > time() - CACHE_TTL
+) {
+    header("Content-Type: application/json");
+    header("X-Debug-Cache-Hit: complete");
+    readfile($completeCacheFile);
+    //use fast response time to allow cache cleaning for 500ms
+    $cacheCleanEnd = microtime(true) + 0.5;
+    $cacheFiles = glob(CACHE_DIR . "/*");
+    do {
+        $cacheFile = array_shift($cacheFiles);
+        if (filemtime($cacheFile) < time() - CACHE_TTL) {
+            unlink($cacheFile);
+        }
+    } while (microtime(true) <= $cacheCleanEnd && count($cacheFiles) > 0);
+
+    exit();
+}
+
+if (
+    !file_exists($urlCacheFile) ||
+    filemtime($urlCacheFile) < time() - CACHE_TTL
+) {
+    $dlStart = microtime(true);
+    $size = 0;
+    $fp_in = fopen($url, "r");
+    $fp_out = fopen($urlCacheFile, "w");
+    while ($fp_in && !feof($fp_in)) {
+        $size += fwrite($fp_out, fread($fp_in, 1024 * 1024));
+        if ($size > MAX_FILE_SIZE) {
+            header("HTTP/1.1 400 Bad Request");
+            echo "File is too big";
+            fclose($fp_in);
+            fclose($fp_out);
+            unlink($urlCacheFile);
+            exit();
+        }
+    }
+    fclose($fp_in);
+    fclose($fp_out);
+    $dlEnd = microtime(true);
+    $dlTime = round($dlEnd - $dlStart, 3);
+    header("X-Debug-Download-Time: $dlTime s");
+    $prefixes = ["B", "KB", "MB", "GB", "TB", "PB"];
+    $prefix = array_shift($prefixes);
+    while ($size > 1500) {
+        $prefix = array_shift($prefixes);
+        $size = $size / 1024;
+    }
+    $hsize = round($size, 3) . " " . $prefix;
+    header("X-Debug-Download-Size: $hsize");
+} else {
+    header("X-Debug-Cache-Hit: url");
+}
+
+$errors = false;
+
+try {
+    $parseStart = microtime(true);
+    $ical = new ICal($urlCacheFile, [
+        "defaultTimeZone" => "UTC",
+    ]);
+    $events = $ical->eventsFromRange(
+        date("Y-m-d", strtotime("today")),
+        date("Y-m-d", strtotime("today + 90 days"))
+    );
+    $parseEnd = microtime(true);
+    $parseTime = round($parseEnd - $parseStart, 3);
+    header("X-Debug-Parse-Time: $parseTime s");
+
+    while (count($events) > $maxItems) {
+        array_pop($events);
+    }
+
+    $events = array_map(function (Event $event) {
+        $r = [];
+        @$r["summary"] = $event->summary;
+        @$r["description"] = $event->description;
+        @$r["location"] = $event->location;
+        @$r["start"] = $event->dtstart_array[2];
+        @$r["end"] = $event->dtend_array[2];
+        @$r["duration"] = $event->duration;
+        @$r["url"] = $event->url;
+        @$r["status"] = $event->status;
+        return $r;
+    }, $events);
+    usort($events, function ($a, $b) {
+        return $a["start"] - $b["start"];
+    });
+} catch (\Exception $e) {
+    header("HTTP/1.1 500 Internal Server Error");
+    echo "Error parsing ical file";
+    exit();
+}
+
+$data = json_encode(
+    $events,
+    JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT
+);
+file_put_contents($completeCacheFile, $data);
+header("Content-Type: application/json");
+echo $data;
+
+foreach (glob(CACHE_DIR . "/*") as $file) {
+    if (filemtime($file) < time() - CACHE_TTL) {
+        unlink($file);
+    }
+}
diff --git a/htdocs/app.js b/htdocs/app.js
new file mode 100644
index 0000000..1eda5fa
--- /dev/null
+++ b/htdocs/app.js
@@ -0,0 +1,86 @@
+let previewData = [];
+let getData = function () {
+  let data = {};
+  data.url = document.getElementById("url").value;
+  data.start = document.getElementById("start").value;
+  data.end = document.getElementById("end").value;
+  data.maxitems = document.getElementById("maxitems").value;
+  for (let key in data) {
+    if (data[key] == "") {
+      delete data[key];
+    }
+  }
+  return data;
+};
+
+document.getElementById("form").onsubmit = function () {
+  // Get data from form
+  let data = getData();
+  // Send data to server as url form encoded
+  let xhr = new XMLHttpRequest();
+  let outputEl = document.getElementById("preview");
+  outputEl.innerHTML = "Loading...";
+  outputEl.classList.add("loading");
+  outputEl.classList.remove("error");
+  let url = "/api/?" + new URLSearchParams(data).toString();
+  xhr.open("get", url);
+  xhr.onload = function () {
+    if (xhr.status == 200) {
+      outputEl.classList.remove("loading");
+      outputEl.classList.remove("error");
+    } else {
+      outputEl.classList.remove("loading");
+      outputEl.classList.add("error");
+    }
+    document.getElementById("preview").innerHTML = xhr.responseText;
+    previewData = JSON.parse(xhr.responseText);
+  };
+  xhr.send();
+
+  document.getElementById("previewUrl").value =
+    window.location.protocol + "//" + window.location.host + url;
+  return false;
+};
+let start = document.getElementById("start");
+start.onchange = function () {
+  let val = this.value;
+  if (val == "") {
+    val = start.getAttribute("placeholder");
+  }
+  let xhr = new XMLHttpRequest();
+  xhr.open(
+    "get",
+    "/strtotime/?" +
+      new URLSearchParams({ date: val, format: "Y-m-d" }).toString()
+  );
+  xhr.onload = function () {
+    if (xhr.status == 200) {
+      document.querySelector(".previewStart").textContent = xhr.responseText;
+    }
+  };
+  xhr.send();
+};
+start.onkeyup = start.onchange;
+start.onchange();
+
+let end = document.getElementById("end");
+end.onchange = function () {
+  let val = this.value;
+  if (val == "") {
+    val = end.getAttribute("placeholder");
+  }
+  let xhr = new XMLHttpRequest();
+  xhr.open(
+    "get",
+    "/strtotime/?" +
+      new URLSearchParams({ date: val, format: "Y-m-d" }).toString()
+  );
+  xhr.onload = function () {
+    if (xhr.status == 200) {
+      document.querySelector(".previewEnd").textContent = xhr.responseText;
+    }
+  };
+  xhr.send();
+};
+end.onkeyup = end.onchange;
+end.onchange();
diff --git a/htdocs/composer.json b/htdocs/composer.json
new file mode 100644
index 0000000..9377f0d
--- /dev/null
+++ b/htdocs/composer.json
@@ -0,0 +1,5 @@
+{
+  "require": {
+    "johngrogg/ics-parser": "^2.1"
+  }
+}
diff --git a/htdocs/composer.lock b/htdocs/composer.lock
new file mode 100644
index 0000000..bedacc1
--- /dev/null
+++ b/htdocs/composer.lock
@@ -0,0 +1,155 @@
+{
+  "_readme": [
+    "This file locks the dependencies of your project to a known state",
+    "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
+    "This file is @generated automatically"
+  ],
+  "content-hash": "10482d28879f2a0ab5cd26452cfd53d5",
+  "packages": [
+    {
+      "name": "johngrogg/ics-parser",
+      "version": "v2.2.2",
+      "source": {
+        "type": "git",
+        "url": "https://github.com/u01jmg3/ics-parser.git",
+        "reference": "69c80471a0a99142ebc72b21c2bc084e81a7c4f4"
+      },
+      "dist": {
+        "type": "zip",
+        "url": "https://api.github.com/repos/u01jmg3/ics-parser/zipball/69c80471a0a99142ebc72b21c2bc084e81a7c4f4",
+        "reference": "69c80471a0a99142ebc72b21c2bc084e81a7c4f4",
+        "shasum": ""
+      },
+      "require": {
+        "ext-mbstring": "*",
+        "php": ">=5.3.9"
+      },
+      "require-dev": {
+        "phpunit/phpunit": "^4",
+        "squizlabs/php_codesniffer": "~2.9.1"
+      },
+      "type": "library",
+      "autoload": {
+        "psr-0": {
+          "ICal": "src/"
+        }
+      },
+      "notification-url": "https://packagist.org/downloads/",
+      "license": ["MIT"],
+      "authors": [
+        {
+          "name": "Jonathan Goode",
+          "role": "Developer/Owner"
+        },
+        {
+          "name": "John Grogg",
+          "email": "john.grogg@gmail.com",
+          "role": "Developer/Prior Owner"
+        }
+      ],
+      "description": "ICS Parser",
+      "homepage": "https://github.com/u01jmg3/ics-parser",
+      "keywords": [
+        "iCalendar",
+        "ical",
+        "ical-parser",
+        "ics",
+        "ics-parser",
+        "ifb"
+      ],
+      "support": {
+        "issues": "https://github.com/u01jmg3/ics-parser/issues",
+        "source": "https://github.com/u01jmg3/ics-parser/tree/v2.2.2"
+      },
+      "funding": [
+        {
+          "url": "https://github.com/sponsors/u01jmg3",
+          "type": "github"
+        }
+      ],
+      "time": "2020-11-02T10:28:33+00:00"
+    },
+    {
+      "name": "symfony/polyfill-mbstring",
+      "version": "v1.27.0",
+      "source": {
+        "type": "git",
+        "url": "https://github.com/symfony/polyfill-mbstring.git",
+        "reference": "8ad114f6b39e2c98a8b0e3bd907732c207c2b534"
+      },
+      "dist": {
+        "type": "zip",
+        "url": "https://api.github.com/repos/symfony/polyfill-mbstring/zipball/8ad114f6b39e2c98a8b0e3bd907732c207c2b534",
+        "reference": "8ad114f6b39e2c98a8b0e3bd907732c207c2b534",
+        "shasum": ""
+      },
+      "require": {
+        "php": ">=7.1"
+      },
+      "provide": {
+        "ext-mbstring": "*"
+      },
+      "suggest": {
+        "ext-mbstring": "For best performance"
+      },
+      "type": "library",
+      "extra": {
+        "branch-alias": {
+          "dev-main": "1.27-dev"
+        },
+        "thanks": {
+          "name": "symfony/polyfill",
+          "url": "https://github.com/symfony/polyfill"
+        }
+      },
+      "autoload": {
+        "files": ["bootstrap.php"],
+        "psr-4": {
+          "Symfony\\Polyfill\\Mbstring\\": ""
+        }
+      },
+      "notification-url": "https://packagist.org/downloads/",
+      "license": ["MIT"],
+      "authors": [
+        {
+          "name": "Nicolas Grekas",
+          "email": "p@tchwork.com"
+        },
+        {
+          "name": "Symfony Community",
+          "homepage": "https://symfony.com/contributors"
+        }
+      ],
+      "description": "Symfony polyfill for the Mbstring extension",
+      "homepage": "https://symfony.com",
+      "keywords": ["compatibility", "mbstring", "polyfill", "portable", "shim"],
+      "support": {
+        "source": "https://github.com/symfony/polyfill-mbstring/tree/v1.27.0"
+      },
+      "funding": [
+        {
+          "url": "https://symfony.com/sponsor",
+          "type": "custom"
+        },
+        {
+          "url": "https://github.com/fabpot",
+          "type": "github"
+        },
+        {
+          "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
+          "type": "tidelift"
+        }
+      ],
+      "time": "2022-11-03T14:55:06+00:00"
+    }
+  ],
+  "packages-dev": [],
+  "aliases": [],
+  "minimum-stability": "stable",
+  "stability-flags": [],
+  "prefer-stable": false,
+  "prefer-lowest": false,
+  "platform": [],
+  "platform-dev": [],
+  "plugin-api-version": "2.3.0"
+}
diff --git a/htdocs/index.html b/htdocs/index.html
new file mode 100644
index 0000000..c0fd326
--- /dev/null
+++ b/htdocs/index.html
@@ -0,0 +1,50 @@
+<html>
+  <head>
+    <title>ICAL2JSON helper</title>
+    <link rel="stylesheet" href="styles.css" />
+  </head>
+  <body>
+    <h1>URL-Builder</h1>
+    <form id="form">
+      <label><input type="url" name="url" id="url" />ICAL-URL</label>
+      <label
+        ><input type="text" name="start" id="start" placeholder="today" />Start
+        Date in a strtotime() compatible format (<span
+          class="previewStart"
+        ></span
+        >)</label
+      >
+      <label
+        ><input
+          type="text"
+          name="end"
+          id="end"
+          placeholder="last day of next month"
+        />End Date in a strtotime() compatible format (<span
+          class="previewEnd"
+        ></span
+        >)</label
+      >
+      <label
+        ><input
+          type="number"
+          name="maxitems"
+          id="maxitems"
+          min="1"
+          max="100"
+          step="1"
+          placeholder="100"
+        />maximal number of items shown</label
+      >
+      <label><input type="submit" value="Preview" /></label>
+    </form>
+    <h1>Preview data</h1>
+    <label
+      ><input type="text" aria-disabled="true" id="previewUrl" value="" /> Your
+      json url</label
+    >
+    <div id="preview">No data</div>
+
+    <script src="app.js"></script>
+  </body>
+</html>
diff --git a/htdocs/strtotime/index.php b/htdocs/strtotime/index.php
new file mode 100644
index 0000000..9428c49
--- /dev/null
+++ b/htdocs/strtotime/index.php
@@ -0,0 +1,4 @@
+<?php
+$date = strtotime($_REQUEST["date"]);
+$format = isset($_REQUEST["format"]) ? $_REQUEST["format"] : "U";
+echo date($format, $date);
diff --git a/htdocs/styles.css b/htdocs/styles.css
new file mode 100644
index 0000000..cd3bc5b
--- /dev/null
+++ b/htdocs/styles.css
@@ -0,0 +1,56 @@
+label {
+  display: block;
+}
+label > input {
+  margin: 1em;
+  height: 3em;
+  width: 50em;
+}
+body {
+  font-family: Arial, Helvetica, sans-serif;
+  font-size: 1em;
+  color: #333;
+  background: #fff;
+}
+
+#preview {
+  font-family: monospace;
+  white-space: pre;
+  border: 0.3em inset #4c4;
+  min-height: 3em;
+}
+#preview.error {
+  border-color: #c44;
+}
+#preview.loading {
+  border-color: #cc4;
+}
+textarea {
+  display: block;
+  margin: 1em;
+  width: calc(100% - 2em);
+}
+
+.grow-wrap {
+  display: grid;
+}
+.grow-wrap::after {
+  content: attr(data-replicated-value) " ";
+
+  white-space: pre-wrap;
+
+  visibility: hidden;
+}
+.grow-wrap > textarea {
+  resize: none;
+
+  overflow: hidden;
+}
+.grow-wrap > textarea,
+.grow-wrap::after {
+  border: 1px solid black;
+  padding: 0.5rem;
+  font: inherit;
+
+  grid-area: 1 / 1 / 2 / 2;
+}