<?php

namespace App\Console\Commands;

use Illuminate\Console\Command;
use Illuminate\Console\Concerns\CallsCommands;
use Illuminate\Support\Facades\Http;
use Laravel\Forge\Forge;
use Laravel\Forge\Resources\Daemon;

class SwapOctaneServer extends Command
{
    use CallsCommands;

    private Forge $forgeApi;
    private $serverId;
    private $siteId;
    private $bluePort;
    private $greenPort;

    const BLUE  = 'blue';
    const GREEN = 'green';

    /**
     * The name and signature of the console command.
     *
     * @var string
     */
    protected $signature = 'octane:swap-server';

    /**
     * The console command description.
     *
     * @var string
     */
    protected $description = 'Start a new Octane daemon and swap the port in the nginx config';

    /**
     * Execute the console command.
     *
     * @return int
     */
    public function handle(Forge $forge)
    {
        $this->forgeApi  = $forge;
        $this->serverId  = config('services.forge.server_id');
        $this->siteId    = config('services.forge.site_id');
        $this->bluePort  = config('services.forge.blue_port');  // 8001
        $this->greenPort = config('services.forge.green_port'); // 8002

        $nginxPort = $this->getNginxPort();

        $this->info('Current nginx port: ' . $nginxPort);

        $blueIsActive = $nginxPort === $this->bluePort;

        $this->start($blueIsActive ? static::GREEN : static::BLUE);
        $this->stop($blueIsActive ? static::BLUE : static::GREEN);
    }

    private function getNginxPort(): int
    {
        $config = $this->forgeApi->siteNginxFile($this->serverId, $this->siteId);

        preg_match('/(proxy_pass http:\/\/127.0.0.1:)(\d+)\$/', $config, $matches);

        return $matches[2];
    }

    private function start($server)
    {
        $this->info('Start server: ' . $server);

        // make sure there's no dangling daemon
        $this->stop($server);

        $this->forgeApi->createDaemon($this->serverId, [
            "command"   => "bash start-{$server}-server.sh",
            "user"      => "forge",
            "directory" => "/home/forge/website.com/current",   // symbolic link
        ]);

        $port = $server === static::BLUE ? $this->bluePort : $this->greenPort;

        $this->info('Polling server on port: ' . $server);

        retry(
            300,
            fn () => Http::timeout(1)
                ->connectTimeout(1)
                ->get("127.0.0.1:{$port}"),
            100
        );

        $this->updateNginxConfig($port);
    }

    private function updateNginxConfig($newPort)
    {
        $this->info('Updating nginx config to port: ' . $newPort);

        $config = $this->forgeApi->siteNginxFile($this->serverId, $this->siteId);

        $config = preg_replace_callback('/(proxy_pass http:\/\/127.0.0.1:)(\d+)\$/', function ($matches) use ($newPort) {
            return $matches[1] . $newPort . '$';
        }, $config);

        $this->forgeApi->updateSiteNginxFile($this->serverId, $this->siteId, $config);
    }

    private function stop($server)
    {
        $forge = $this->forgeApi;

        /** @var Daemon $daemon */
        $daemon = collect($forge->daemons($this->serverId))->firstWhere('command', "bash start-{$server}-server.sh");

        if ($daemon) {
            $this->info('Wait for pending requests on server: ' . $server);

            usleep(config('octane.max_execution_time') * 1000 * 1000);

            $this->info('Stop server: ' . $server);

            rescue(fn () => $forge->deleteDaemon($daemon->serverId, $daemon->id));
        }
    }
}