CLI: Add a wp surge flush command

Fixes #14

include/cli.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * All things CLI
+ *
+ * @package Surge
+ */
+
+namespace Surge;
+
+use WP_CLI;
+
+include_once( __DIR__ . '/common.php' );
+
+class CLI_Commands {
+
+	/**
+	 * Flush all cached data.
+	 *
+	 * ## OPTIONS
+	 *
+	 * [--delete]
+	 * : By default flushing cache will invalidate all existing entries. Using the --delete flag will also delete these entries from disk, which is slower.
+	 * ---
+	 * default: false
+	 */
+	public function flush( $args, $assoc_args ) {
+		$assoc_args = wp_parse_args( $assoc_args, [
+			'delete' => false,
+		] );
+
+		if ( ! $assoc_args['delete'] ) {
+			expire( '/' );
+			WP_CLI::success( 'Set all existing page cache entries as expired.' );
+			return;
+		}
+
+		require_once ABSPATH . 'wp-admin/includes/class-wp-filesystem-base.php';
+		require_once ABSPATH . 'wp-admin/includes/class-wp-filesystem-direct.php';
+
+		$fs = new \WP_Filesystem_Direct( false );
+		$r = $fs->rmdir( CACHE_DIR, true );
+		if ( ! $r ) {
+			WP_CLI::error( sprintf( 'Could not recursively delete %s. Please check permissions.', CACHE_DIR ) );
+		}
+
+		WP_CLI::success( 'All page cache deleted successfully.' );
+	}
+}
+
+WP_CLI::add_command( 'surge', __NAMESPACE__ . '\\CLI_Commands', [
+	'shortdesc' => 'Control Surge page caching.',
+] );

surge.php

@@ -31,6 +31,10 @@
 		include_once( __DIR__ . '/include/cron.php' );
 	}
 
+	if ( defined( 'WP_CLI' ) && WP_CLI ) {
+		include_once( __DIR__ . '/include/cli.php' );
+	}
+
 	include_once( __DIR__ . '/include/invalidate.php' );
 } );