Initial project scaffold

Set up MVC architecture with front controller, router, autoloader,
database singleton, and Docker Compose stack (Nginx + PHP-FPM + MariaDB).
Includes DB schema, responsive layout, dev tooling (php-cs-fixer,
parallel-lint), and documentation.

6 files changed, 201 insertions, 0 deletions

diff --git a/src/app/Controllers/HomeController.php b/src/app/Controllers/HomeController.php
new file mode 100644
index 0000000..8c462a0
--- /dev/null
+++ b/src/app/Controllers/HomeController.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+// Handles the home page and verifies database connectivity.
+
+namespace App\Controllers;
+
+use App\Database;
+
+class HomeController
+{
+    public function index(): void
+    {
+        $db = Database::getInstance()->getPdo();
+        $stmt = $db->query('SELECT 1');
+        $dbStatus = $stmt ? 'Connected' : 'Failed';
+
+        $content = __DIR__ . '/../Views/home/index.php';
+        include __DIR__ . '/../Views/layouts/main.php';
+    }
+}
diff --git a/src/app/Database.php b/src/app/Database.php
new file mode 100644
index 0000000..f4dff79
--- /dev/null
+++ b/src/app/Database.php
@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+// PDO singleton for MariaDB connections.
+
+namespace App;
+
+class Database
+{
+    private static ?Database $instance = null;
+    private \PDO $pdo;
+
+    private function __construct()
+    {
+        $host = getenv('MYSQL_HOST') ?: 'mariadb';
+        $db = getenv('MYSQL_DATABASE');
+        $user = getenv('MYSQL_USER');
+        $pass = getenv('MYSQL_PASSWORD');
+
+        $this->pdo = new \PDO(
+            "mysql:host=$host;dbname=$db;charset=utf8mb4",
+            $user,
+            $pass,
+            [
+                \PDO::ATTR_ERRMODE => \PDO::ERRMODE_EXCEPTION,
+                \PDO::ATTR_DEFAULT_FETCH_MODE => \PDO::FETCH_ASSOC,
+                \PDO::ATTR_EMULATE_PREPARES => false,
+            ]
+        );
+    }
+
+    public static function getInstance(): self
+    {
+        if (self::$instance === null) {
+            self::$instance = new self();
+        }
+        return self::$instance;
+    }
+
+    public function getPdo(): \PDO
+    {
+        return $this->pdo;
+    }
+}
diff --git a/src/app/Router.php b/src/app/Router.php
new file mode 100644
index 0000000..9bfe09d
--- /dev/null
+++ b/src/app/Router.php
@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+// Regex-based HTTP router that dispatches requests to controller methods.
+
+namespace App;
+
+class Router
+{
+    private array $routes = [];
+
+    public function get(string $path, string $controller, string $method): void
+    {
+        $this->routes[] = ['GET', $path, $controller, $method];
+    }
+
+    public function post(string $path, string $controller, string $method): void
+    {
+        $this->routes[] = ['POST', $path, $controller, $method];
+    }
+
+    public function dispatch(): void
+    {
+        $requestMethod = $_SERVER['REQUEST_METHOD'];
+        $uri = parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH);
+        $uri = rtrim($uri, '/') ?: '/';
+
+        foreach ($this->routes as [$method, $path, $controller, $action]) {
+            if ($method !== $requestMethod) {
+                continue;
+            }
+
+            // Convert route placeholders to named regex capture groups.
+            // Example with route '/post/{id}' and request '/post/42':
+            //   1. preg_replace turns '{id}' into '(?P<id>[^/]+)'
+            //      result: '#^/post/(?P<id>[^/]+)$#'
+            //   2. preg_match against '/post/42' produces:
+            //      [0 => '/post/42', 'id' => '42', 1 => '42']
+            //   3. array_filter keeps only string keys: ['id' => '42']
+            //   4. PostController->show('42') is called
+            $pattern = preg_replace('#\{(\w+)\}#', '(?P<$1>[^/]+)', $path);
+            $pattern = '#^' . $pattern . '$#';
+
+            if (preg_match($pattern, $uri, $matches)) {
+                $params = array_filter($matches, 'is_string', ARRAY_FILTER_USE_KEY);
+                $controllerClass = "App\\Controllers\\$controller";
+                $instance = new $controllerClass();
+                $instance->$action(...array_values($params));
+                return;
+            }
+        }
+
+        http_response_code(404);
+        echo '404 Not Found';
+    }
+}
diff --git a/src/app/Views/home/index.php b/src/app/Views/home/index.php
new file mode 100644
index 0000000..f5cde93
--- /dev/null
+++ b/src/app/Views/home/index.php
@@ -0,0 +1,3 @@
+<?php // Home page: displays a welcome message and database connection status.?>
+<h1>Welcome to Camagru</h1>
+<p>Database status: <?= htmlspecialchars($dbStatus) ?></p>
diff --git a/src/app/Views/layouts/main.php b/src/app/Views/layouts/main.php
new file mode 100644
index 0000000..b4c7dad
--- /dev/null
+++ b/src/app/Views/layouts/main.php
@@ -0,0 +1,35 @@
+<?php // Base HTML layout: header with navigation, content slot, and footer.?>
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Camagru</title>
+    <link rel="stylesheet" href="/css/style.css">
+</head>
+<body>
+    <header>
+        <nav>
+            <a href="/" class="logo">Camagru</a>
+            <div class="nav-links">
+                <a href="/gallery">Gallery</a>
+                <?php if (isset($_SESSION['user_id'])): ?>
+                    <a href="/editor">Editor</a>
+                    <a href="/profile">Profile</a>
+                    <a href="/logout">Logout</a>
+                <?php else: ?>
+                    <a href="/login">Login</a>
+                    <a href="/register">Register</a>
+                <?php endif; ?>
+            </div>
+        </nav>
+    </header>
+    <main>
+        <?php include $content; ?>
+    </main>
+    <footer>
+        <p>Camagru &copy; <?= date('Y') ?></p>
+    </footer>
+    <script src="/js/app.js"></script>
+</body>
+</html>
diff --git a/src/app/bootstrap.php b/src/app/bootstrap.php
new file mode 100644
index 0000000..835615b
--- /dev/null
+++ b/src/app/bootstrap.php
@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+// Application bootstrap: loads .env, registers the autoloader, and configures error reporting.
+
+session_start();
+
+// Load .env
+$envFile = dirname(__DIR__, 2) . '/.env';
+if (file_exists($envFile)) {
+    $lines = file($envFile, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
+    foreach ($lines as $line) {
+        if (str_starts_with(trim($line), '#')) {
+            continue;
+        }
+        $parts = explode('=', $line, 2);
+        if (count($parts) === 2) {
+            $key = trim($parts[0]);
+            $value = trim($parts[1]);
+            $_ENV[$key] = $value;
+            putenv("$key=$value");
+        }
+    }
+}
+
+// Autoloader
+spl_autoload_register(function (string $class): void {
+    $prefix = 'App\\';
+    if (!str_starts_with($class, $prefix)) {
+        return;
+    }
+    $relative = substr($class, strlen($prefix));
+    $file = __DIR__ . '/' . str_replace('\\', '/', $relative) . '.php';
+    if (file_exists($file)) {
+        require $file;
+    }
+});
+
+// Error reporting
+error_reporting(E_ALL);
+ini_set('display_errors', '0');
+ini_set('log_errors', '1');