New upgrade command

README.md

@@ -62,6 +62,7 @@ This should print the Kirby CLI version and a list of available commands
 - kirby remove:command
 - kirby roots
 - kirby unzip
+- kirby upgrade
 - kirby uuid:generate
 - kirby uuid:populate
 - kirby uuid:remove

commands/upgrade.php

@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types = 1);
+
+use Kirby\CLI\CLI;
+
+return [
+	'description' => 'Upgrades the Kirby core',
+	'args' => [
+		'version' => [
+			'description'  => 'The version corresponding with the tag name in the kirby repo',
+			'defaultValue' => 'latest'
+		]
+	],
+	'command' => static function (CLI $cli): void {
+		$version   = $cli->arg('version');
+		$kirby     = $cli->kirby();
+		$kirbyRoot = $kirby->root('kirby');
+		$folder    = 'kirby.' . $version;
+
+		// if entered version is `latest`
+		// get exact version to compare current kirby version
+		if ($version === 'latest') {
+			$release = json_decode(file_get_contents('https://getkirby.com/security.json'));
+			$version = $release->latest;
+		}
+
+		// checks current kirby version whether same or higher
+		if (version_compare($version, $kirby->version(), '<=') === true) {
+			throw new Exception('Current Kirby version is the same or higher than the version you are trying to upgrade to');
+		}
+
+		// confirms the process when major version upgrade available
+		if ((int)$version > (int)$kirby->version()) {
+			$cli->confirmToContinue(
+				'Major version upgrade detected. Are you sure you want to proceed?',
+				fn () => throw new Exception('Major version upgrade has been canceled')
+			);
+		}
+
+		if (is_dir($cli->dir() . '/' . $folder) === true) {
+			throw new Exception('The ' . $folder . ' directory exists');
+		}
+
+		$cli->out('Upgrading Kirby from ' . $kirby->version() . ' to ' . $version . ' …');
+		$cli->run('install:repo', 'getkirby/kirby', $folder, $version);
+
+		// move current kirby to temp directory as backup
+		rename($kirbyRoot, $kirbyRoot . '.old');
+
+		// move new kirby to current root
+		rename($cli->dir() . '/' . $folder, $kirbyRoot);
+
+		// delete old kirby
+		$cli->rmdir($kirbyRoot . '.old');
+
+		// delete temp panel directory
+		$cli->rmdir($kirby->root('media') . '/panel');
+
+		$cli->success('The Kirby has been upgraded to ' . $version);
+	}
+];