<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, OPTIONS');
header('Access-Control-Allow-Headers: Content-Type');

if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
    http_response_code(204);
    exit;
}

// ── Parse the route from the URL ──────────────────────────────────────────────
// Expected format: /api/register, /api/upload, /api/save etc.
$path   = parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH);
$path   = rtrim($path, '/');
$parts  = explode('/', $path);

// Last segment is the route e.g. "register" from "/api/register"
$route  = end($parts);

$validRoutes = [
    'register',
    'upload',
    'save',
    'file',
    'files',
    'delete',
    'stats',
    'serve'
];

if (!in_array($route, $validRoutes)) {
    http_response_code(404);
    echo json_encode([
        'error'          => 'Unknown route',
        'available'      => array_map(fn($r) => "/api/{$r}", $validRoutes),
        'docs'           => [
            'POST /api/register'        => 'Create a new user site. Body: {"username":"alice"}',
            'POST /api/upload'          => 'Upload files. Form data: username + files[]',
            'POST /api/save'            => 'Save file from editor. Body: {"username":"alice","filepath":"index.php","content":"..."}',
            'GET  /api/file'            => 'Get file content. Params: ?username=alice&filepath=index.php',
            'GET  /api/files'           => 'List all files. Params: ?username=alice',
            'POST /api/delete'          => 'Delete file or site. Body: {"username":"alice","filepath":"index.php"} or {"username":"alice","delete_all":true}',
            'GET  /api/stats'           => 'Disk usage and user count',
            'GET  /site/username/file'  => 'View a user site e.g. /site/alice/index.php',
        ]
    ]);
    exit;
}

// ── Route to the correct file ─────────────────────────────────────────────────
require_once __DIR__ . "/{$route}.php";