From c403243350981d45a561357f0bc26fcf81fbc582 Mon Sep 17 00:00:00 2001
From: alyx <alyx@aleteoryx.me>
Date: Sat, 25 May 2024 14:40:40 -0400
Subject: Feature-complete

---
 visitors.php | 381 ++++++++++++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 339 insertions(+), 42 deletions(-)

diff --git a/visitors.php b/visitors.php
index 92abedb..37859ff 100644
--- a/visitors.php
+++ b/visitors.php
@@ -9,25 +9,79 @@ define('GIT_REPO', 'https://git.aleteoryx.me/cgit/visitors_dot_php/');
 
 // Title: string
 //
-// The title for the page and <title> element.
+// The title for the page.
 
 $config['title'] = 'Guestbook';
 
 
+// Site name: ?string
+//
+// The name of the larger website.
+
+//$config['site_name'] = "Jonny Sims's Magical Mystery Machine";
+
+
+// Blurb: ?string
+//
+// If set, will display under the main heading.
+
+//$config['blurb'] = 'Look what all these nice people said!';
+
+
+// Date format: string
+//
+// Format for the date displayed next to entries.
+// Format docs: <https://www.php.net/manual/en/datetime.format.php>
+
+$config['date_format'] = 'Y/m/d H:i';
+
+
 // Custom CSS: ?string
 //
-// Will be injected after the builtin CSS. Respects `use_path_info` when being served.
+// Data should be CSS code to inject into the page.
+// Link should be the URL of a stylesheet.
+// Only set one, or neither.
 
-//$config['custom_css'] = 'body { background: red; }';
+//$config['custom_css_data'] = 'body { background: red; }';
+//$config['custom_css_link'] = '/static/guestbook.css';
+
+
+// Custom JS: ?string
+//
+// Data should be JavaScript code to inject into the page.
+// Link should be the URL of a JS script.
+// Only set one, or neither.
+// Data is loaded into a normal script tag, with no module support.
+
+//$config['custom_js_data'] = 'alert("Custom JS!")';
+//$config['custom_js_link'] = '/static/guestbook.js';
 
 
 // Use builtin CSS: bool
 //
-// Toggles the builtin CSS
+// Enable builtin CSS?
 
 $config['builtin_css'] = true;
 
 
+// Content Order: choice
+//
+// 0 - Visits, Form
+// 1 - Form, Visits
+
+$config['content_order'] = 0;
+
+
+/* CONFIG OPTIONS - FORM */
+
+// Use captcha: bool
+//
+// Enable the captcha?
+// Recommended.
+
+$config['captcha'] = true;
+
+
 // Form mode: choice
 //
 // 0 - Only ask for name
@@ -37,7 +91,7 @@ $config['builtin_css'] = true;
 //
 // Any entries in one mode will display fine in any other.
 
-$config['form_mode'] = 0;
+$config['form_mode'] = 1;
 
 
 // E-Mail display mode: choice
@@ -53,13 +107,36 @@ $config['email_display'] = 1;
 
 // E-Mail icon/link: ?string
 //
-// Link should be a link to an image for the email icon. Icon should be the icon's data, base64 encoded, prefixed with `<mimetype>:`.
+// Link should be a link to an image for the email icon.
+// Icon should be the icon's data, base64 encoded, prefixed with `<mimetype>:`.
 // Only set one, or neither. This option only applies for email_display modes 0 and 1.
 
 //$config['email_link'] = '/static/my_cool_email_icon.gif';
 //$config['email_icon'] = 'image/png:...';
 
 
+// Message box dimensions: int, int
+//
+// Sets the rows= and cols= html attributes on the <textarea? for the message.
+
+$config['message_rows'] = 5;
+$config['message_cols'] = 60;
+
+
+// Form prompt: string
+//
+// Text for a header above the form
+
+$config['form_prompt'] = "Write something in my guestbook!";
+
+
+// Submit button text: string
+//
+// Sets the text of the submit button
+
+$config['submit_text'] = "Sign!";
+
+
 /* CONFIG OPTIONS - BACKEND */
 
 // Send assets via PATH_INFO: bool
@@ -68,7 +145,7 @@ $config['email_display'] = 1;
 // Otherwise, inline them into a single HTML document.
 // Only enable this if your webserver supports PATH_INFO.
 
-$config['use_path_info'] = true;
+$config['use_path_info'] = false;
 
 
 // Database path: string
@@ -85,6 +162,17 @@ $config['use_path_info'] = true;
 $config['db'] = 'visitors.csv';
 
 
+// Captcha hook: ?fn() => ['prompt' => string, 'answer' => string]
+//
+// A function used to generate captchas. If unset, will be a builtin function.
+// The answer is kept server-side, so it can be anything.
+//
+// Ensure you've taken adequate steps to ensure the session is kept secure.
+// <https://www.php.net/manual/en/features.session.security.management.php>
+
+//$config['captcha_hook'] = fn() => ['prompt' => 'What's the year?', 'answer' => date('Y')];
+
+
 /* --- END OF CONFIG, CODE BELOW, PROBABLY DON'T EDIT PAST THIS POINT --- */
 
 
@@ -99,11 +187,77 @@ if (!isset($config['email_link'])) { // stolen from <https://forum.melonland.net
   }
 }
 
+if (!isset($config['custom_css_link'])) {
+  if ($config['use_path_info'] && isset($config['custom_css_data'])) {
+    $config['custom_css_link'] = $_SERVER['SCRIPT_NAME'].'/custom_css';
+  }
+}
+
+if (!isset($config['custom_js_link'])) {
+  if ($config['use_path_info'] && isset($config['custom_js_data'])) {
+    $config['custom_js_link'] = $_SERVER['SCRIPT_NAME'].'/custom_js';
+  }
+}
+
+$config['captcha_hook'] ??= 'builtin_captcha';
+
 
 /* BUILTIN_CSS */
 
 define('BUILTIN_CSS', <<<EOT
+body {
+  background: #666;
+
+  display: flex;
+  flex-direction: column;
+  align-items: center;
 
+  padding-left: min(30%, calc(50%) - 5cm);
+  padding-right: min(30%, calc(50%) - 5cm);
+}
+body > h1, footer {
+  color: white;
+}
+body > a, footer > a {
+  color: cyan;
+}
+body > a:visited, footer > a:visited {
+  color: pink;
+}
+main {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  width: 100%;
+}
+main > article {
+  background: #bbb;
+  width: 100%;
+  margin: 0.1cm;
+  padding: 0.1cm;
+  border-radius: 0.1cm;
+  border: 1px white solid;
+}
+form {
+  background: #bbb;
+  margin: 1cm;
+  padding: 0.1cm;
+  border-radius: 0.1cm;
+  border: 1px white solid;
+}
+.visit-info > time {
+  float: right;
+}
+#submission_error {
+  margin-bottom: 0.5cm;
+}
+#submission_error > span {
+  background: lightcoral;
+  color: black;
+  font-weight: bold;
+  padding: 0.1cm;
+  border-radius: 0.1cm;
+}
 EOT);
 
 
@@ -122,7 +276,11 @@ if (@$_SERVER['PATH_INFO']) {
     break;
   case '/custom_css':
     header('Content-Type: text/css');
-    echo $config['custom_css']??'';
+    echo $config['custom_css_data']??'';
+    break;
+  case '/custom_js':
+    header('Content-Type: text/javascript');
+    echo $config['custom_js_data']??'';
     break;
   default:
     http_response_code('404');
@@ -136,25 +294,34 @@ if (@$_SERVER['PATH_INFO']) {
 
 /* DATABASES */
 
-// db_row: ['id' => int (only for list_rows), 'name' => string, 'message' => string, 'email' => ?string, 'website' => ?string, 'timestamp' => string (or DateTimeInterface for list_rows)]
+// db_row: ['id' => int (only for list_rows), 'name' => string, 'message' => string, 'website' => ?string, 'email' => ?string, 'timestamp' => string (or DateTimeInterface for list_rows)]
 // message is pre-escaped at insert time.
 // timestamp is DateTimeInterface::ISO8601_EXPANDED format.
 
 abstract class Database {
-  public function append_row(string $name, string $message, ?string $email = NULL, ?string $website = NULL) {
+  private ?array $data_cache;
+
+  public function append_row(string $name, string $message, ?string $website = NULL, ?string $email = NULL) {
+    unset($this->data_cache);
     $timestamp = date(DATE_ISO8601_EXPANDED);
-    $this->_append_row(compact('name', 'message', 'email', 'website', 'timestamp'));
+    $this->_append_row(compact('name', 'message', 'website', 'email', 'timestamp'));
   }
 
   public function list_rows(): array {
+    if (isset($this->data_cache))
+      return $this->data_cache;
+
     $data = $this->_list_rows();
     foreach($data as &$row) {
       $row['timestamp'] = DateTime::createFromFormat(DATE_ISO8601_EXPANDED, $row['timestamp']);
     }
+
+    $this->data_cache = $data;
     return $data;
   }
 
   public function delete_row(int $id): bool {
+    unset($this->data_cache);
     return $this->_delete_row($id);
   }
 
@@ -233,7 +400,7 @@ final class JsonlDatabase extends FileDatabase {
 
 // notes: `id` is not stable
 final class CsvDatabase extends FileDatabase {
-  private const array KEY_ORDER = ['id', 'name', 'message', 'email', 'website', 'timestamp'];
+  private const array KEY_ORDER = ['id', 'name', 'message', 'website', 'email', 'timestamp'];
 
   protected function save() {
     $fp = fopen($this->file, 'w');
@@ -254,11 +421,11 @@ final class SqliteDatabase extends Database {
   public function __construct(string $file) {
     $this->handle = new Sqlite3($file);
     if (!$this->handle->querySingle('SELECT count(*) FROM sqlite_master'))
-      $this->handle->exec('CREATE TABLE visitors (id INTEGER PRIMARY KEY, name TEXT NOT NULL, message TEXT NOT NULL, email TEXT, website TEXT, timestamp TEXT NOT NULL)');
+      $this->handle->exec('CREATE TABLE visitors (id INTEGER PRIMARY KEY, name TEXT NOT NULL, message TEXT NOT NULL, website TEXT, email TEXT, timestamp TEXT NOT NULL)');
   }
 
   protected function _append_row(array $db_row) {
-    $stmt = $this->handle->prepare('INSERT INTO visitors (name, message, email, website, timestamp) VALUES (:name, :message, :email, :website, :timestamp)');
+    $stmt = $this->handle->prepare('INSERT INTO visitors (name, message, website, email, timestamp) VALUES (:name, :message, :website, :email, :timestamp)');
     foreach($db_row as $key => $value)
       $stmt->bindValue($key, $value);
     $stmt->execute();
@@ -300,37 +467,90 @@ function get_database_for_file(string $file): Database {
 
 $db = get_database_for_file($config['db']);
 
-//$db->append_row('foo', 'bar');
+
+/* POST HANDLING */
+
+function builtin_captcha(): array {
+  global $db;
+  return ['prompt' => 'What is the name of the most recent visitor?',
+          'answer' => trim($db->list_rows()[0]['name'])];
+}
+
+header('Refresh: 1400');
+session_start(['cookie_lifetime' => 1440]);
+
+function cleanup_post() {
+  global $config;
+  if ($config['captcha'] && (@$_SESSION['captcha'] !== htmlentities($_POST['captcha']??''))) {
+    return "Invalid captcha!";
+  }
+  if (isset($_POST['site-or-email'])) {
+    $_POST['site-or-email'] = trim($_POST['site-or-email']);
+    if (preg_match('/^(?:https?|gopher|gemini):\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/', $_POST['site-or-email']))
+      $_POST['website'] = htmlentities($_POST['site-or-email']);
+    else if (preg_match('/^[a-zA-Z0-9.!#$%&’*+\/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/', $_POST['site-or-email']))
+      $_POST['email'] = htmlentities($_POST['site-or-email']);
+    else return "Invalid Website URL or E-Mail!";
+  }
+  else {
+    if (isset($_POST['website'])) {
+      $_POST['website'] = trim($_POST['website']);
+      if (!preg_match('/^(?:https?|gopher|gemini):\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/', $_POST['website']))
+        return "Invalid Website URL!";
+      $_POST['website'] = htmlentities($_POST['website']);
+    }
+    if (isset($_POST['email'])) {
+      $_POST['email'] = trim($_POST['email']);
+      if (!preg_match('/^[a-zA-Z0-9.!#$%&’*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/', $_POST['email']))
+        return "Invalid E-Mail!";
+      $_POST['email'] = htmlentities($_POST['email']);
+    }
+  }
+  $_POST['name'] = htmlentities($_POST['name']);
+  $_POST['message'] = htmlentities($_POST['message']);
+}
+
+$form_error;
+if ($_SERVER['REQUEST_METHOD'] == 'POST') {
+  $form_error = cleanup_post();
+  if (!$form_error) {
+    $db->append_row($_POST['name'], $_POST['message'], @$_POST['website'], @$_POST['email']);
+  }
+}
+
 
 /* ACTUAL UI */
 
 $ed_1_or_3 = $config['email_display'] == 1 || $config['email_display'] == 3;
 
-?>
-<!doctype html>
-<html>
-<head>
-<meta charset='utf-8' />
-<title><?= $config['title'] ?></title>
-<?= $config['use_path_info'] ?
-      '<link rel=stylesheet href="'.$_SERVER['REQUEST_URI'].'/builtin_css"/><link rel=stylesheet href="'.$_SERVER['REQUEST_URI'].'/custom_css"/>' :
-      '<style>'.BUILTIN_CSS.'</style>'.(@$config['custom_css'] ? '<style>'.$config['custom_css'].'</style>' : '') ?>
-</head>
-<body>
-  <h1><?= $config['title'] ?></h1>
+function author_link($row) {
+  global $ed_1_or_3;
+
+  if ($row['website'])
+    return '<a href="'.$row['website'].'">'.$row['name'].'</a>';
+  else if ($row['email'] && $ed_1_or_3)
+    return '<a href="mailto:'.$row['email'].'">'.$row['name'].'</a>';
+  else return $row['name'];
+}
+
+function email_element($row) {
+  global $ed_1_or_3, $config;
+
+  if (!$row['website'] && $row['email'] && $ed_1_or_3)
+    return '';
+  else if ($row['email'])
+    return match($config['email_display']) {
+      0, 1 => '<a href="mailto:'.$row['email'].'"><img alt="e-mail icon" src="'.($config['email_link']??$_SERVER['SCRIPT_NAME'].'/email_icon').'" /></a>',
+      2, 3 => '<a href="mailto:'.$row['email'].'">[e-mail]</a>',
+      4 => 'mail:&nbsp<u>'.str_replace(['@', '.'], [' at ', ' dot '], $row['email']).'</u>'
+    };
+  else return '';
+}
+
+function render_visits() {
+  global $config, $db; ?>
   <main>
-    <?php foreach($db->list_rows() as $row):
-            $author_link = $row['website'] ?
-                             '<a href="'.$row['website'].'">'.$row['name'].'</a>' :
-                             (($row['email'] && $ed_1_or_3) ?
-                               '<a href="mailto:'.$row['email'].'">'.$row['name'].'</a>' :
-                               $row['name']);
-            $email_element = $row['email'] && (($row['website'] && $ed_1_or_3) || !$ed_1_or_3) ?
-                               match ($config['email_display']) {
-                                 0, 1 => '<a href="mailto:'.$row['email'].'"><img alt="e-mail icon" src="'.($config['email_link']??$_SERVER['REQUEST_URI'].'/email_icon').'" /></a>',
-                                 2, 3 => '<a href="mailto:'.$row['email'].'">[e-mail]</a>',
-                                 4 => 'mail:&nbsp<u>'.str_replace(['@', '.'], [' at ', ' dot '], $row['email']).'</u>'
-                               } : ''; ?>
+    <?php foreach($db->list_rows() as $row): ?>
     <article id=visit-<?= $row['id'] ?>
              data-visit-id=<?= $row['id'] ?>
              data-visit-name="<?= $row['name'] ?>"
@@ -338,13 +558,90 @@ $ed_1_or_3 = $config['email_display'] == 1 || $config['email_display'] == 3;
              data-visit-email="<?= $row['email'] ?>"
              data-visit-website="<?= $row['website'] ?>">
       <div class='visit-info'>
-        <span class='author-link'><?= $author_link ?></span>&nbsp;&nbsp;<span class='email'><?= $email_element ?></span>
-        <span class='wide'>
-        <time datetime="<?= $row['timestamp']->format(DATE_ISO8601) ?>"><?= $row['timestamp']->format("Y/m/d H:i") ?></time>
+        <span class='author-link'><?= author_link($row) ?></span>&nbsp;&nbsp;<span class='email'><?= email_element($row) ?></span>
+        <time datetime="<?= $row['timestamp']->format(DATE_ISO8601) ?>"><?= $row['timestamp']->format($config['date_format']) ?></time>
       </div>
       <q><?= $row['message'] ?></q>
     </article>
     <?php endforeach; ?>
   </main>
+<?php }
+
+function render_form() {
+  global $config, $form_error; ?>
+  <form id=submission method=POST>
+    <h2><?= $config['form_prompt'] ?></h2>
+    <?php if (isset($form_error)): ?>
+      <div id=submission_error><span><?= $form_error ?></span></div>
+    <?php endif; ?>
+
+    <label for=name>Name:</label> <input type=text placeholder='Alice P. Hacker' name=name required /><br />
+
+    <?php if ($config['form_mode'] == 1 || $config['form_mode'] == 2): ?>
+    <label for=website>Website (optional):</label> <input type=url placeholder='https://example.com' name=website /><br />
+    <?php endif;
+          if ($config['form_mode'] == 2): ?>
+    <label for=email>E-Mail (optional):</label> <input type=email placeholder='ahacker@example.com' name=email /><br />
+    <?php endif;
+          if ($config['form_mode'] == 3): ?>
+    <label for=site-or-email>Website or E-Mail (optional):</label> <input type=text pattern='^(?:https?|gopher|gemini):\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$|^[a-zA-Z0-9.!#$%&’*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$' placeholder='...' name=site-or-email /><br />
+    <?php endif; ?>
+
+    <label for=message>Message:</label><br />
+    <textarea name=message placeholder='Write something...' rows="<?= $config['message_rows'] ?>" cols="<?= $config['message_cols'] ?>" required></textarea><br />
+
+    <?php if ($config['captcha']):
+            $captcha = $config['captcha_hook']();
+            $_SESSION['captcha'] = $captcha['answer']; ?>
+    <label for=captcha>Captcha: <?= $captcha['prompt'] ?></label><br /><input type=text name=captcha required /><br />
+    <?php endif; ?>
+
+    <button name=submit><?= $config['submit_text'] ?></button>
+  </form>
+<?php }
+
+?>
+<!doctype html>
+<html>
+<head>
+  <meta charset='utf-8' />
+  <meta name=description content="<?= @$config['blurb'] ?>" />
+  <meta name='og:name' content="<?= $config['title'] ?>">
+  <meta name='og:description' content="<?= @$config['blurb'] ?>">
+  <meta name='og:site_name' content="<?= @$config['site_name'] ?>">
+  <meta name='og:type' content=website>
+  <title><?= (isset($config['site_name']) ? $config['site_name'].' - ' : '').$config['title'] ?></title>
+
+  <?php if ($config['builtin_css']):
+          if ($config['use_path_info']): ?>
+      <link rel=stylesheet href="<?= $_SERVER['SCRIPT_NAME'] ?>/builtin_css"/>
+    <?php else: ?>
+      <style><?= BUILTIN_CSS ?></style>
+    <?php endif;
+        endif; ?>
+
+  <?php if (isset($config['custom_css_link'])): ?>
+    <link rel=stylesheet href="<?= $config['custom_css_link'] ?>"/>
+  <?php elseif (isset($config['custom_css_data'])): ?>
+    <style><?= $config['custom_css_data'] ?></style>
+  <?php endif; ?>
+</head>
+<body>
+  <h1><?= $config['title'] ?></h1>
+  <?php if ($config['content_order'] == 0): ?>
+    <a href='#submission'>Jump to form</a>
+    <?php render_visits();
+          render_form();
+        elseif ($config['content_order'] == 1):
+          render_form();
+          render_visits();
+        endif; ?>
+  <footer>Powered by <a href="<?= GIT_REPO ?>">visitors_dot_php</a> version <?= VERSION ?>.</footer>
+
+  <?php if (isset($config['custom_js_link'])): ?>
+    <script src="<?= $config['custom_js_link'] ?>"></script>
+  <?php elseif (isset($config['custom_js_data'])): ?>
+    <script><?= $config['custom_js_data'] ?></script>
+  <?php endif; ?>
 </body>
 </html>
-- 
cgit v1.2.3-54-g00ecf