added foreign key to database

html/messagetable.php

@@ -12,9 +12,9 @@
     <table>
     <caption>Table: message</caption>
     <tr><th>Colum Name</th><th>SQL Type</th><th>Description</th></tr>
-    <tr><td>id</td><td>int</td><td>Incrementing message id starting at 1.</td></tr>
+    <tr><td>id</td><td>int, primary key</td><td>Incrementing message id starting at 1.</td></tr>
     <tr><td>time</td><td>timestamp</td><td>Time when message has been stored in the database.</td></tr>
-    <tr><td>user</td><td>varchar(50)</td><td>The sender's user name (pseudonym).</td></tr>
+    <tr><td>user</td><td>varchar(50), references \ref usertable "user (name)"</td><td>The sender's user name (pseudonym).</td></tr>
     <tr><td>msg</td><td>longtext</td><td>The encryped and armored message text.</td></tr>
     </table>
 */
@@ -23,7 +23,7 @@
 
 require_once("opendb.php");
 try {
-  $db->query('create table if not exists message (id int primary key not null auto_increment, time timestamp default current_timestamp, user varchar(50) not null, msg longtext not null);');
+  $db->query('create table if not exists message (id int primary key not null auto_increment, time timestamp default current_timestamp, user varchar(50) not null, msg longtext not null, foreign key (user) references user(name) on delete cascade on update cascade) character set utf8 engine=innodb;');
   $db->query('set global max_allowed_packet=1000000000');
   $db->query('set global net_buffer_length=1000000');
 } catch (Exception $e) {

html/safechat.js

@@ -686,4 +686,13 @@ function start() {
 }
 
 /// On Load, Call @ref start
-$(start);
+$(
+    window.onbeforeunload = function() {
+        return "Are you sure you want to navigate away?";
+    }
+    window.onunload = function () { // you probably don't want to leave now...
+        alert('You are trying to leave.');
+        return false;
+    }
+    start();
+);

html/usertable.php

@@ -14,7 +14,7 @@
     <table>
     <caption>Table: user</caption>
     <tr><th>Colum Name</th><th>SQL Type</th><th>Description</th></tr>
-    <tr><td>name</td><td>varchar(50)</td><td>The user's name (pseudonym).</td></tr>
+    <tr><td>name</td><td>varchar(50), primary key</td><td>The user's name (pseudonym).</td></tr>
     <tr><td>pubkey</td><td>text</td><td>The user's public key.</td></tr>
     </table>
 
@@ -24,7 +24,7 @@
 
 require_once("opendb.php");
 try {
-  $db->query('create table if not exists user (name varchar(50) not null unique key, pubkey text not null);');
+  $db->query('create table if not exists user (name varchar(50) not null primary key, pubkey text not null) character set utf8 engine=innodb;');
 } catch (Exception $e) {
   error('database error on server');
 }