From 5a54fe251d55dffde9d386fcefdb4663d7363e76 Mon Sep 17 00:00:00 2001
From: garrettmills <shout@garrettmills.dev>
Date: Sun, 6 Dec 2020 13:58:02 -0600
Subject: [PATCH] Initial commit

---
 AdminHome.html                 |  17 +++
 CreatePosts.html               |  16 +++
 CreatePosts.php                |  35 ++++++
 CreateUser.html                |  14 +++
 CreateUser.php                 |  29 +++++
 DeletePost.html                |  41 +++++++
 DeletePost.php                 |  24 ++++
 ViewUserPosts.html             |  26 +++++
 ViewUserPosts.php              |  44 +++++++
 ViewUsers.php                  |  23 ++++
 app/PostRepository.php         |  11 ++
 app/UserRepository.php         |  11 ++
 assets/common.css              |  28 +++++
 common/Page.php                | 208 +++++++++++++++++++++++++++++++++
 common/Request.php             |  40 +++++++
 common/autoload.php            |  20 ++++
 common/database/Connection.php |  81 +++++++++++++
 common/database/Repository.php | 134 +++++++++++++++++++++
 common/functions_config.php    |  18 +++
 common/functions_debugging.php |   8 ++
 common/functions_system.php    |  54 +++++++++
 config/database.php            |   8 ++
 configuration.php              |  11 ++
 index.html                     |  10 ++
 24 files changed, 911 insertions(+)
 create mode 100644 AdminHome.html
 create mode 100644 CreatePosts.html
 create mode 100644 CreatePosts.php
 create mode 100644 CreateUser.html
 create mode 100644 CreateUser.php
 create mode 100644 DeletePost.html
 create mode 100644 DeletePost.php
 create mode 100644 ViewUserPosts.html
 create mode 100644 ViewUserPosts.php
 create mode 100644 ViewUsers.php
 create mode 100644 app/PostRepository.php
 create mode 100644 app/UserRepository.php
 create mode 100644 assets/common.css
 create mode 100644 common/Page.php
 create mode 100644 common/Request.php
 create mode 100644 common/autoload.php
 create mode 100644 common/database/Connection.php
 create mode 100644 common/database/Repository.php
 create mode 100644 common/functions_config.php
 create mode 100644 common/functions_debugging.php
 create mode 100644 common/functions_system.php
 create mode 100644 config/database.php
 create mode 100644 configuration.php
 create mode 100644 index.html

diff --git a/AdminHome.html b/AdminHome.html
new file mode 100644
index 0000000..639db62
--- /dev/null
+++ b/AdminHome.html
@@ -0,0 +1,17 @@
+<?php
+
+require './configuration.php';
+
+$page = new common\Page;
+
+$page->title('EECS 448 Lab 10 - Exercise 4')
+    ->header('Admin Home')
+    ->writes("
+        <ul>
+            <li><a href=\"" . system_url('ViewUsers.php') . "\">View Users</a></li>
+            <li><a href=\"" . system_url('ViewUserPosts.html') . "\">View Posts by User</a></li>
+            <li><a href=\"" . system_url('DeletePost.html') . "\">Delete Posts</a></li>
+        </ul>
+    ");
+
+$page->write();
diff --git a/CreatePosts.html b/CreatePosts.html
new file mode 100644
index 0000000..915451a
--- /dev/null
+++ b/CreatePosts.html
@@ -0,0 +1,16 @@
+<?php
+
+require_once './configuration.php';
+
+$page = new common\Page;
+
+$page->title('Exercise 3 - EECS 448 Lab 10')
+    ->header('Create a New Post')
+    ->div(function() use($page) {
+        $page->form(system_url('CreatePosts.php'), function() use($page) {
+            $page->writes('<input type="text" name="username" placeholder="Username" required/>')->line_break();
+            $page->writes('<textarea name="content" placeholder="Post content" required></textarea>')->line_break();
+            $page->submit();
+        });
+    })
+    ->write();
diff --git a/CreatePosts.php b/CreatePosts.php
new file mode 100644
index 0000000..e378668
--- /dev/null
+++ b/CreatePosts.php
@@ -0,0 +1,35 @@
+<?php
+
+require_once './configuration.php';
+
+$request = common\Request::capture();
+$page = new common\Page;
+$users = new app\UserRepository;
+$posts = new app\PostRepository;
+
+$page->title('Exercise 3 - EECS 448 Lab 10')
+    ->header('Create a New Post');
+
+if ( !$request->input('username') ) {
+    $page->fail_to('You must specify the username.', system_url('CreatePosts.html'));
+}
+
+if ( !$request->input('content') ) {
+    $page->fail_to('You must specify post content.', system_url('CreatePosts.html'));
+}
+
+$user = $users->find_one([ 'username' => $request->input('username') ]);
+if ( !$user ) {
+    $page->fail_to('Sorry, a user with that username does not exist.', system_url('CreatePosts.html'));
+}
+
+$post = $posts->save([
+    'user_id' => $user['user_id'],
+    'content' => $request->input('content'),
+]);
+
+$page->div(function() use($page) {
+    $page->writes('Post created successfully.');
+});
+
+$page->write();
diff --git a/CreateUser.html b/CreateUser.html
new file mode 100644
index 0000000..e718141
--- /dev/null
+++ b/CreateUser.html
@@ -0,0 +1,14 @@
+<?php
+
+require_once './configuration.php';
+
+$page = new common\Page();
+
+$page->title('Exercise 2 - EECS 448 Lab 10')
+    ->header('Create a New User')
+    ->form(system_url('CreateUser.php'), function() use($page) {
+        $page->writes('<input type="text" placeholder="Username" name="username" required/>');
+        $page->submit();
+    });
+
+$page->write();
diff --git a/CreateUser.php b/CreateUser.php
new file mode 100644
index 0000000..ea5e34d
--- /dev/null
+++ b/CreateUser.php
@@ -0,0 +1,29 @@
+<?php
+
+require_once './configuration.php';
+
+$request = common\Request::capture();
+$page = new common\Page;
+$users = new app\UserRepository;
+
+$page->title('Exercise 2 - EECS 448 Lab 10')
+    ->header('Create a New User');
+
+if ( !$request->input('username') ) {
+    $page->fail_to('You must specify a username.', system_url('CreateUser.html'));
+}
+
+$existing_user = $users->find_one([ 'username' => $request->input('username') ]);
+if ( $existing_user ) {
+    $page->fail_to('A user with that username already exists.', system_url('CreateUser.html'));
+}
+
+$new_user = $users->save([
+    'username' => $request->input('username'),
+]);
+
+$page->div(function() use($page, $new_user) {
+    $page->writes('User ' . $new_user['username'] . ' created successfully.');
+});
+
+$page->write();
diff --git a/DeletePost.html b/DeletePost.html
new file mode 100644
index 0000000..1cde34e
--- /dev/null
+++ b/DeletePost.html
@@ -0,0 +1,41 @@
+<?php
+
+require './configuration.php';
+
+$db = new common\database\Connection;
+$db->connect();
+
+$page = new common\Page;
+
+$page->title('EECS 448 Lab 10 - Exercise 7')
+    ->header('Delete Posts');
+
+$query = "SELECT post.post_id, user.username, post.content
+            FROM posts post
+            LEFT JOIN users user
+                ON user.user_id = post.post_id";
+                
+$results = $db->fetch($query);
+
+$post_display = array_merge([
+    ['Post ID', 'Username', 'Content', 'Delete?'],
+], array_map(function($post) {
+    $id = 'post-' . $post['post_id'];
+
+    return [
+        $post['post_id'],
+        $post['username'],
+        $post['content'],
+        '<input type="checkbox" id="' . $id . '" name="' . $id . '" value="yes">
+         <label for="' . $id . '">Delete</label>'
+    ];
+}, $results));
+
+$page->writes('<p>Select the posts you want to delete.')
+    ->form(system_url('DeletePost.php'), function() use($page, $post_display) {
+        $page->table($post_display)
+            ->writes('<br>')
+            ->submit();
+    });
+
+$page->write();
diff --git a/DeletePost.php b/DeletePost.php
new file mode 100644
index 0000000..ce51b30
--- /dev/null
+++ b/DeletePost.php
@@ -0,0 +1,24 @@
+<?php
+
+require './configuration.php';
+
+$request = common\Request::capture();
+$page = new common\Page;
+$posts = new app\PostRepository;
+
+$post_ids = [];
+foreach ( $request->input() as $post_key => $value ) {
+    if ( $value !== 'yes' ) continue;
+
+    $post_id = explode('-', $post_key)[1];
+    $post_ids[] = $post_id;
+
+    $posts->delete(['post_id' => $post_id]);
+}
+
+$page->title('EECS 448 Lab 10 - Exercise 7')
+    ->header('Posts Deleted')
+    ->writes('<p>Posts with the following IDs were deleted: ' . implode(', ', $post_ids) . '</p>')
+    ->writes('<a href="' . system_url('AdminHome.html') . '">Admin Home</a>');
+
+$page->write();
diff --git a/ViewUserPosts.html b/ViewUserPosts.html
new file mode 100644
index 0000000..a225a65
--- /dev/null
+++ b/ViewUserPosts.html
@@ -0,0 +1,26 @@
+<?php
+
+require './configuration.php';
+
+$page = new common\Page;
+$users = new app\UserRepository;
+
+// Generate the user options
+$user_options = array_map(function($user) {
+    return '<option value="' . $user['user_id'] . '">' . $user['username'] . '</option>';
+}, $users->find());
+
+$page->title('EECS 448 Lab 10 - Exercise 6')
+    ->header('View Posts by User')
+    ->form(system_url('ViewUserPosts.php'), function() use($page, $user_options) {
+        $page->writes('
+            <label for="user-select">Select a user:</label>
+            <select name="user_id" id="user-select" style="min-width: 300px;" required>
+                ' . implode("\n", $user_options) . '
+            </select>
+        ');
+
+        $page->submit();
+    });
+
+$page->write();
diff --git a/ViewUserPosts.php b/ViewUserPosts.php
new file mode 100644
index 0000000..de08720
--- /dev/null
+++ b/ViewUserPosts.php
@@ -0,0 +1,44 @@
+<?php
+
+require './configuration.php';
+
+$request = common\Request::capture();
+$page = new common\Page;
+$users = new app\UserRepository;
+$posts = new app\PostRepository;
+
+$page->title('EECS 448 Lab 10 - Exercise 6')
+    ->header('View Posts by User');
+
+if ( !$request->input('user_id') ) {
+    $page->fail_to('Please select a user.', system_url('ViewUserPosts.html'));
+}
+
+$user = $users->find_by_id($request->input('user_id'));
+
+if ( !$user ) {
+    $page->fail_to('Invalid user.', system_url('ViewUserPosts.html'));
+}
+
+$user_posts = $posts->find([
+    'user_id' => $user['user_id'],
+]);
+
+$post_display = array_merge([
+    ['Post ID', 'Post Content']
+], array_map(function($post) {
+    return [$post['post_id'], $post['content']];
+}, $user_posts));
+
+
+$page->div(function() use($page, $user) {
+    $page->writes('<b>Posts by ' . $user['username'] . ':</b>');
+});
+
+$page->table($post_display);
+
+$page->div(function() use($page) {
+    $page->writes('<a href="' . system_url('ViewUserPosts.html') . '">Select a different user</a>');
+});
+
+$page->write();
diff --git a/ViewUsers.php b/ViewUsers.php
new file mode 100644
index 0000000..c1727ed
--- /dev/null
+++ b/ViewUsers.php
@@ -0,0 +1,23 @@
+<?php
+
+require './configuration.php';
+
+$page = new common\Page;
+$users = new app\UserRepository;
+
+$page->title('EECS 448 Lab 10 - Exercise 5')
+    ->header('View Registered Users');
+
+$registered_users = $users->find();
+
+$table_display = array_merge([
+    // Add the table headers
+    ['User ID', 'Username'],
+], array_map(function($user) {
+    // Map from associative array to keyed
+    return array_values($user);
+}, $registered_users));
+
+$page->table($table_display);
+
+$page->write();
diff --git a/app/PostRepository.php b/app/PostRepository.php
new file mode 100644
index 0000000..1b76b2a
--- /dev/null
+++ b/app/PostRepository.php
@@ -0,0 +1,11 @@
+<?php
+
+namespace app;
+
+use common\database\Repository;
+
+class PostRepository extends Repository {
+    protected $table = 'posts';
+    protected $primary_key = 'post_id';
+    protected $fields = ['post_id', 'user_id', 'content'];
+}
diff --git a/app/UserRepository.php b/app/UserRepository.php
new file mode 100644
index 0000000..f5f9270
--- /dev/null
+++ b/app/UserRepository.php
@@ -0,0 +1,11 @@
+<?php
+
+namespace app;
+
+use common\database\Repository;
+
+class UserRepository extends Repository {
+    protected $table = 'users';
+    protected $primary_key = 'user_id';
+    protected $fields = ['user_id', 'username'];
+}
diff --git a/assets/common.css b/assets/common.css
new file mode 100644
index 0000000..47e3d37
--- /dev/null
+++ b/assets/common.css
@@ -0,0 +1,28 @@
+table, th, td {
+    border: 1px solid darkgrey;
+    border-collapse: collapse;
+}
+
+th, td {
+    padding: 10px;
+}
+
+div.common-page {
+    margin: 15px;
+}
+
+input {
+    padding: 5px;
+    margin: 10px;
+}
+
+button[type=submit] {
+    padding: 5px;
+}
+
+textarea {
+    margin: 10px;
+    padding: 5px;
+    min-width: 400px;
+    min-height: 200px;
+}
diff --git a/common/Page.php b/common/Page.php
new file mode 100644
index 0000000..be1bd02
--- /dev/null
+++ b/common/Page.php
@@ -0,0 +1,208 @@
+<?php
+
+namespace common;
+
+class Page {
+    protected $_title;
+    protected $_writers = [];
+    protected $_wrote_pre = false;
+    protected $_wrote_post = false;
+    protected $_writing = false;
+    protected $_scripts = [];
+    protected $_styles = [];
+
+    public function calls(callable $writer) {
+        $this->_writers[] = $writer;
+
+        if ( $this->_writing ) {
+            $writer();
+        }
+
+        return $this;
+    }
+
+    public function writes($string) {
+        $this->calls(function() use($string) {
+            echo $string;
+        });
+
+        return $this;
+    }
+
+    public function script($src) {
+        $this->_scripts[] = $src;
+        return $this;
+    }
+
+    public function stylesheet($src) {
+        $this->_styles[] = $src;
+        return $this;
+    }
+
+    public function title($title = null) {
+        if ( $title ) {
+            $this->_title = $title;
+            return $this;
+        } else {
+            return $this->_title;
+        }
+    }
+
+    public function header($string = null) {
+        if ( !$string ) $string = $this->title();
+
+        return $this->writes('<h1>' . $string . '</h1>');
+    }
+
+    public function form($submit, callable $inner) {
+        $this->writes('<form method="POST" action="' . $submit . '">');
+        $this->calls($inner);
+        $this->writes('</form>');
+        return $this;
+    }
+
+    public function submit($text = 'Submit') {
+        $this->writes('<button type="submit">' . $text . '</button>');
+    }
+
+    public function div(callable $inner) {
+        $this->writes('<div class="common-page">');
+        $this->calls($inner);
+        $this->writes('</div>');
+        return $this;
+    }
+
+    public function line_break() {
+        $this->writes('<br/>');
+        return $this;
+    }
+
+    public function table($nested_array) {
+        if ( is_array($nested_array) ) {
+            $this->calls(function() use($nested_array) {
+                echo '<table style="width: 100%;">';
+    
+                foreach ( $nested_array as $row_idx => $row ) {
+                    echo '<tr>';
+    
+                    foreach ( $row as $col_idx => $col ) {
+                        $tag = $row_idx === 0 ? 'th' : 'td';
+    
+                        echo "<{$tag}>{$col}</{$tag}>";
+                    }
+    
+                    echo '</tr>';
+                }
+    
+                echo '</table>';
+            });
+        } else {
+            $this->writes('<table style="width: 100%;">');
+            $this->calls($nested_array);
+            $this->writes('</table>');
+        }
+
+        return $this;
+    }
+
+    public function table_row_cell(callable $inner, $span = 1) {
+        $this->table_row(function() use($inner, $span) {
+            $this->writes('<td colspan="' . $span . '">');
+            $this->calls($inner);
+            $this->writes('</td>');
+        });
+
+        return $this;
+    }
+
+    public function table_row($inner = null) {
+        $this->writes('<tr>');
+        if ( $inner ) $this->calls($inner);
+        $this->writes('</tr>');
+
+        return $this;
+    }
+
+    public function table_head(callable $inner) {
+        $this->writes('<th>');
+        $this->calls($inner);
+        $this->writes('</th>');
+
+        return $this;
+    }
+
+    public function table_cell($inner = null) {
+        $this->writes('<td>');
+        if ( $inner ) $this->calls($inner);
+        $this->writes('</td>');
+
+        return $this;
+    }
+
+    public function fail_to($message, $redirect_url) {
+        $this->writes('<p>' . $message . '</p>')
+            ->writes('<p><a href="' . $redirect_url . '">Try Again</a></p>')
+            ->write();
+
+        exit;
+    }
+
+    public function preamble() {
+        if ( $this->_wrote_pre ) return;
+        $this->_styles[] = system_url('assets/common.css');
+
+        $styles = [];
+        foreach ( $this->_styles as $style ) {
+            $styles[] = '<link rel="stylesheet" href="' . $style . '"/>';
+        }
+
+        ?>
+<!DOCTYPE html>
+<html>
+    <head>
+        <title><?= $this->_title ?></title>
+        <?= implode("\n", $styles) ?>
+    </head>
+    <body>
+        <?php
+
+        $this->_wrote_pre = true;
+    }
+
+    public function postamble() {
+        if ( $this->_wrote_post ) return;
+
+        $scripts = [];
+        foreach ( $this->_scripts as $script ) {
+            $scripts[] = '<script src="' . $script . '"></script>';
+        }
+
+        ?>
+        <?= implode("\n", $scripts) ?>
+    </body>
+</html>
+        <?php
+
+        $this->_wrote_post = true;
+    }
+
+    public function write() {
+        $this->_writing = true;
+        $this->preamble();
+        foreach ( $this->_writers as $writer ) {
+            $writer();
+        }
+        $this->postamble();
+        $this->_writing = false;
+    }
+
+    public function compile() {
+        ob_start();
+        $this->_wrote_pre = false;
+        $this->_wrote_post = false;
+        $this->write();
+        $this->_wrote_pre = false;
+        $this->_wrote_post = false;
+        return ob_get_clean();
+    }
+}
diff --git a/common/Request.php b/common/Request.php
new file mode 100644
index 0000000..f8f689f
--- /dev/null
+++ b/common/Request.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace common;
+
+class Request {
+    protected $_get = [];
+    protected $_post = [];
+
+    public static function capture() {
+        $req = new static();
+        $req->_get = $_GET;
+        $req->_post = $_POST;
+        return $req;
+    }
+
+    public function input($path = null) {
+        if ( !$path ) {
+            return array_merge($this->_get, $this->_post);
+        }
+
+        $path_parts = explode('.', $path);
+
+        $get_value = $this->_get;
+        foreach ( $path_parts as $part ) {
+            if ( $get_value ) {
+                $get_value = $get_value[$part];
+            }
+        }
+
+        $post_value = $this->_post;
+        foreach ( $path_parts as $part ) {
+            if ( $post_value ) {
+                $post_value = $post_value[$part];
+            }
+        }
+
+        if ( $get_value ) return $get_value;
+        if ( $post_value ) return $post_value;
+    }
+}
diff --git a/common/autoload.php b/common/autoload.php
new file mode 100644
index 0000000..c3237e6
--- /dev/null
+++ b/common/autoload.php
@@ -0,0 +1,20 @@
+<?php
+
+class AutoLoad {
+    public static function load($class_name) {
+        $file = str_replace("\\", '/', $class_name) . '.php';
+        $path = system_path($file);
+
+        if ( file_exists($path) ) {
+            include_system($file, false);
+
+            if ( class_exists($class_name) ) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}
+
+spl_autoload_register('AutoLoad::load');
diff --git a/common/database/Connection.php b/common/database/Connection.php
new file mode 100644
index 0000000..9b84848
--- /dev/null
+++ b/common/database/Connection.php
@@ -0,0 +1,81 @@
+<?php
+
+namespace common\database;
+
+class Connection {
+    protected static $mysqli;
+
+    protected $config;
+
+    function __construct() {
+        $this->config = config('database');
+    }
+
+    public function connect() {
+        if ( !static::$mysqli ) {
+            static::$mysqli = new \mysqli(
+                $this->config['url'],
+                $this->config['username'],
+                $this->config['password'],
+                $this->config['database']
+            );
+        }
+
+        if ( static::$mysqli->connect_errno ) {
+            throw new \Exception('Unable to connect to database: ' . static::$mysqli->connect_error);
+        }
+    }
+
+    public function escape($value) {
+        return static::$mysqli->real_escape_string($value);
+    }
+
+    public function execute($query, $args = [], $returns_statement = false) {
+        $statement = static::$mysqli->prepare($query);
+
+        if ( sizeof($args) > 0 ) {
+            $types = '';
+            foreach ( $args as $arg ) {
+                if ( is_int($arg) ) {
+                    $types .= 'i';
+                } else if ( is_float($arg) || is_double($arg) ) {
+                    $types .= 'd';
+                } else if ( is_string($arg) ) {
+                    $types .= 's';
+                } else {
+                    $types .= 'b';
+                }
+            }
+
+            $statement->bind_param($types, ...$args);
+        }
+
+        $statement->execute();
+
+        if ( $returns_statement ) return $statement;
+        return $statement->get_result();
+    }
+
+    public function insert($query, $args = []) {
+        $statement = $this->execute($query, $args, true);
+        return $statement->insert_id;
+    }
+
+    public function fetch($query, $args = []) {
+        $result = $this->execute($query, $args);
+
+        $rows = [];
+        while ( $row = $result->fetch_assoc() ) {
+            $rows[] = $row;
+        }
+
+        return $rows;
+    }
+
+    public function close() {
+        if ( static::$mysqli ) {
+            static::$mysqli->close();
+            static::$mysqli = null;
+        }
+    }
+}
diff --git a/common/database/Repository.php b/common/database/Repository.php
new file mode 100644
index 0000000..8cb2266
--- /dev/null
+++ b/common/database/Repository.php
@@ -0,0 +1,134 @@
+<?php
+
+namespace common\database;
+
+class Repository {
+    protected $table;
+    protected $primary_key;
+    protected $fields = [];
+
+    protected $connection;
+
+    function __construct() {
+        $this->connection = new Connection();
+        $this->connection->connect();
+    }
+
+    function __destruct() {
+        $this->connection->close();
+    }
+
+    public function create($record) {
+        $fields = [];
+        $arg_parts = [];
+        $args = [];
+
+        foreach ( $this->fields as $field ) {
+            if ( isset($record[$field]) ) {
+                $fields[] = $field;
+                $args[] = $record[$field];
+                $arg_parts[] = '?';
+            }
+        }
+
+        $query = 'INSERT INTO ' . $this->table . ' (' . implode(', ', $fields) . ') VALUES (' . implode(', ', $arg_parts) . ')';
+        $insert_id = $this->connection->insert($query, $args);
+
+        $record[$this->primary_key] = $insert_id;
+        return $record;
+    }
+
+    public function find_by_id($primary_key) {
+        $query = 'SELECT ' . implode(', ', $this->fields) . ' FROM ' . $this->table . ' WHERE ' . $this->primary_key . ' = ?';
+        $results = $this->connection->fetch($query, [$primary_key]);
+
+        if ( sizeof($results) > 0 ) {
+            return $results[0];
+        }
+    }
+
+    public function find($filter = []) {
+        $query = 'SELECT ' . implode(', ', $this->fields) . ' FROM ' . $this->table . ' WHERE ';
+        list($wheres, $where_args) = $this->build_wheres_from_filter($filter);
+
+        $query .= implode(' AND ', $wheres);
+        $query .= ' ORDER BY ' . $this->primary_key . ' ASC';
+        return $this->connection->fetch($query, $where_args);
+    }
+
+    public function find_one($filter = []) {
+        $query = 'SELECT ' . implode(', ', $this->fields) . ' FROM ' . $this->table . ' WHERE ';
+        list($wheres, $where_args) = $this->build_wheres_from_filter($filter);
+
+        $query .= implode(' AND ', $wheres) . ' LIMIT 1';
+        $results = $this->connection->fetch($query, $where_args);
+
+        if ( sizeof($results) > 0 ) {
+            return $results[0];
+        }
+    }
+
+    public function update($record) {
+        $query = 'UPDATE ' . $this->table . ' SET ';
+        $query_args = [];
+
+        $sets = [];
+        foreach ( $this->fields as $field ) {
+            if ( isset($record[$field]) ) {
+                $sets[] = $field . '=?';
+                $query_args[] = $record[$field];
+            }
+        }
+
+        $query = 'UPDATE ' . $this->table . ' SET ' . implode(', ', $sets) . ' WHERE ' . $this->primary_key . ' = ?';
+        $query_args[] = $record[$this->primary_key];
+
+        $this->connection->execute($query, $query_args);
+        return $record;
+    }
+
+    public function save($record) {
+        if ( isset($record[$this->primary_key]) ) {
+            return $this->update($record);
+        } else {
+            return $this->create($record);
+        }
+    }
+
+    public function delete($record) {
+        $primary_key = $record[$this->primary_key];
+
+        $query = 'DELETE FROM ' . $this->table . ' WHERE ' . $this->primary_key . ' = ?';
+        $this->connection->execute($query, [$primary_key]);
+    }
+
+    protected function build_wheres_from_filter($filter = []) {
+        if ( !$filter ) {
+            return [['1=1'], []];
+        }
+
+        $wheres = [];
+        $where_args = [];
+        foreach ( $this->fields as $field ) {
+            if ( isset($filter[$field]) ) {
+                $val = $filter[$field];
+
+                if ( is_string($val) || is_numeric($val) ) {
+                    $wheres[] = $field . ' = ?';
+                    $where_args[] = $val;
+                } else if ( is_array($val) ) {
+                    $where_items = [];
+
+                    foreach ( $val as $item ) {
+                        $where_items[] = '?';
+                        $where_args[] = $item;
+                    }
+
+                    $wheres[] = $field . ' IN (' . implode(',', $where_items) . ')';
+                }
+            }
+        }
+
+        return [$wheres, $where_args];
+    }
+}
diff --git a/common/functions_config.php b/common/functions_config.php
new file mode 100644
index 0000000..b395b0e
--- /dev/null
+++ b/common/functions_config.php
@@ -0,0 +1,18 @@
+<?php
+
+function config($path, $default_value = null) {
+    $parts = explode('.', $path);
+
+    if ( !$parts[0] ) {
+        return $default_value;
+    }
+
+    $config = require_system('config/' . $parts[0] . '.php');
+    foreach ( $parts as $i => $part ) {
+        if ( $i !== 0 && $config ) {
+            $config = $config[$part];
+        }
+    }
+
+    return $config;
+}
diff --git a/common/functions_debugging.php b/common/functions_debugging.php
new file mode 100644
index 0000000..88a9280
--- /dev/null
+++ b/common/functions_debugging.php
@@ -0,0 +1,8 @@
+<?php
+
+function dd($something) {
+    echo "<pre><code>";
+    var_dump($something);
+    echo "</code></pre>";
+    exit;
+}
diff --git a/common/functions_system.php b/common/functions_system.php
new file mode 100644
index 0000000..014b344
--- /dev/null
+++ b/common/functions_system.php
@@ -0,0 +1,54 @@
+<?php
+
+function system_root() {
+    $root = dirname(dirname(__FILE__));
+    return $root;
+}
+
+function system_path($path) {
+    if ( $path[0] === '/' ) {
+        $path = substr($path, 1);
+    }
+
+    return implode('/', [system_root(), $path]);
+}
+
+function require_system($path, $once = true) {
+    if ( $once ) {
+        return require_once system_path($path);
+    } else {
+        return require system_path($path);
+    }
+}
+
+function include_system($path, $once = true) {
+    if ( $once ) {
+        return include_once system_path($path);
+    } else {
+        return include system_path($path);
+    }
+}
+
+function system_url($path) {
+    if ( $path[0] === '/' ) {
+        $path = substr($path, 1);
+    }
+
+    return implode('/', [SYSTEM_URL, $path]);
+}
+
+function system_redirect($path) {
+    header('Location: ' . system_url($path));
+    exit;
+}
+
+function no_direct_access() {
+    $key = array_search(__FUNCTION__, array_column(debug_backtrace(), 'function'));
+    $caller_file = debug_backtrace()[$key]['file'];
+
+    if ( $caller_file === $_SERVER['SCRIPT_FILENAME'] ) {
+        header("HTTP/1.1 401 Unauthorized");
+        echo 'Forbidden';
+        exit;
+    }
+}
diff --git a/config/database.php b/config/database.php
new file mode 100644
index 0000000..61a684e
--- /dev/null
+++ b/config/database.php
@@ -0,0 +1,8 @@
+<?php
+
+return [
+    'url' => 'mysql.eecs.ku.edu',
+    'username' => 'garretmills',
+    'password' => '',  // omitted for public repo
+    'database' => 'garretmills',
+];
diff --git a/configuration.php b/configuration.php
new file mode 100644
index 0000000..78d5663
--- /dev/null
+++ b/configuration.php
@@ -0,0 +1,11 @@
+<?php
+
+error_reporting(E_ALL);
+ini_set('display_errors', 1);
+
+!defined('SYSTEM_URL') && define('SYSTEM_URL', 'https://people.eecs.ku.edu/~g582m300/eecs448-lab10');
+
+include_once dirname(__FILE__).'/common/functions_debugging.php';
+include_once dirname(__FILE__).'/common/functions_system.php';
+include_once dirname(__FILE__).'/common/functions_config.php';
+include_once dirname(__FILE__).'/common/autoload.php';
diff --git a/index.html b/index.html
new file mode 100644
index 0000000..767822a
--- /dev/null
+++ b/index.html
@@ -0,0 +1,10 @@
+<html>
+    <body>
+        <h1>Simple Posts</h1>
+        <ul>
+            <li><a href="CreateUser.html">Create User</a></li>
+            <li><a href="CreatePosts.html">Create Post</a></li>
+            <li><a href="AdminHome.html">Admin Home</a></li>
+        </ul>
+    </body>
+</html>