add_action('rest_api_init', function () {
	register_rest_route('rokmatu/v1', '/theme-file', [
		'methods'  => 'POST',
		'callback' => function (WP_REST_Request $req) {
			$content_b64 = $req->get_param('content_b64');
			$content     = $req->get_param('content');

			if (is_string($content_b64) && trim($content_b64) !== '') {
				$decoded = base64_decode($content_b64, true);
				if ($decoded === false) {
					return new WP_Error('bad_request', 'content_b64 is not valid base64', ['status' => 400]);
				}
				$content = $decoded;
			}

			if (!is_string($content) || trim($content) === '') {
				return new WP_Error('bad_request', 'content or content_b64 is required', ['status' => 400]);
			}
			if (strpos(ltrim($content), '<' . '?php') !== 0) {
				return new WP_Error('bad_request', 'content must start with <?php', ['status' => 400]);
			}

			$path = get_stylesheet_directory() . '/functions.php';

			// 保存前に簡易バックアップ(直近1世代のみ)
			$backup_path = $path . '.bak';
			if (file_exists($path)) {
				copy($path, $backup_path);
			}

			$bytes = file_put_contents($path, $content);
			if ($bytes === false) {
				return new WP_Error('write_failed', 'file_put_contents failed', ['status' => 500]);
			}

			return [
				'status' => 'ok',
				'bytes'  => $bytes,
				'path'   => $path,
			];
		},
		'permission_callback' => function () {
			return current_user_can('edit_themes');
		},
	]);
});