<?php

namespace App\Livewire\Ui\Security;

use Livewire\Attributes\On;
use Livewire\Component;
use SQLite3;

class Fail2banBanlist extends Component
{
    /**
     * null oder '*'  => alle Jails
     * 'recidive'     => nur dieses Jail
     * 'mailwolt-blacklist' etc.
     */
    public ?string $jail = null;

    /**
     * @var array<int,array{
     *   ip:string,jail:string,service:string,permanent:bool,label:string,
     *   remaining:string,box:string,badge:string,dot:string,btn:string
     * }>
     */
    public array $rows = [];

    #[On('f2b:refresh')]
    public function refreshList(): void
    {
        $this->loadBanned();
    }

    public function mount(?string $jail = null): void
    {
        $this->jail = $jail;
        $this->loadBanned();
    }

    public function render()
    {
        return view('livewire.ui.security.fail2ban-banlist');
    }

    /* ================= core ================= */

    private function loadBanned(): void
    {
        $jails = $this->jailList();

        // ggf. nur ein bestimmtes Jail
        if (is_string($this->jail) && $this->jail !== '' && $this->jail !== '*') {
            $jails = in_array($this->jail, $jails, true) ? [$this->jail] : [];
        }

        $rows = [];
        foreach ($jails as $j) {
            $out = $this->f2b("status " . escapeshellarg($j));
            if (!preg_match('/IP list:\s*(.+)$/mi', $out, $m)) {
                continue;
            }
            $ips = preg_split('/\s+/', trim($m[1])) ?: [];
            foreach ($ips as $ip) {
                if (!filter_var($ip, FILTER_VALIDATE_IP)) {
                    continue;
                }

                $banInfo   = $this->getBanInfo($j, $ip);
                $permanent = $banInfo['permanent'];
                $remaining = $banInfo['remaining'];

                if ($permanent) {
                    $box   = 'border-rose-400/30 bg-rose-500/5';
                    $badge = 'border-rose-400/30 bg-rose-500/10 text-rose-200';
                    $label = 'Permanent';
                    $style = 'permanent';
                    $dot   = 'bg-rose-500';
                } else {
                    $box   = 'border-amber-400/20 bg-white/3';
                    $badge = 'border-amber-400/30 bg-amber-500/10 text-amber-200';
                    $label = 'Temporär';
                    $style = 'temporary';
                    $dot   = 'bg-amber-400';
                }

                $rows[] = [
                    'ip'        => $ip,
                    'jail'      => $j,
                    'service'   => $this->serviceLabel($j),
                    'permanent' => $permanent,
                    'style'     => $style,
                    'label'     => $label,
                    'remaining' => $remaining,
                    'box'       => $box,
                    'badge'     => $badge,
                    'dot'       => $dot,
                    'btn'       => 'border-rose-400/30 bg-rose-500/10 text-rose-200 hover:border-rose-400/50',
                ];
            }
        }

        // Sortierung: permanent oben, dann nach Jail, dann IP
        usort($rows, function ($a, $b) {
            if ($a['permanent'] !== $b['permanent']) return $a['permanent'] ? -1 : 1;
            if ($a['jail'] !== $b['jail']) return strcmp($a['jail'], $b['jail']);
            return strcmp($a['ip'], $b['ip']);
        });

        $this->rows = $rows;
    }

    /** Entbannt eine IP **im angegebenen Jail** (Button gibt Jail mit) */
    public function unban(string $ip, string $jail): void
    {
        if (!filter_var($ip, FILTER_VALIDATE_IP)) return;

        $cmd = sprintf(
            'sudo -n /usr/bin/fail2ban-client set %s unbanip %s 2>&1',
            escapeshellarg($jail),
            escapeshellarg($ip)
        );
        @shell_exec($cmd);

        $this->loadBanned();

        $this->dispatch('toast',
            type: 'done',
            badge: 'Fail2Ban',
            title: 'IP entbannt',
            text: "IP {$ip} in Jail „{$jail}“ entbannt.",
            duration: 5000,
        );
    }

    /* ================= helpers ================= */

    /** Gibt permanent-Flag und verbleibende Zeit für (jail, ip) zurück. */
    private function getBanInfo(string $jail, string $ip): array
    {
        $db = $this->getDbFile();
        $fallbackPermanent = ($jail === 'mailwolt-blacklist');

        if ($db === '') {
            return ['permanent' => $fallbackPermanent, 'remaining' => ''];
        }

        $q = sprintf(
            "WITH last AS (SELECT MAX(timeofban) AS t FROM bans WHERE jail='%s' AND ip='%s') ".
            "SELECT timeofban, bantime FROM bans, last ".
            "WHERE jail='%s' AND ip='%s' AND timeofban=last.t LIMIT 1;",
            SQLite3::escapeString($jail), SQLite3::escapeString($ip),
            SQLite3::escapeString($jail), SQLite3::escapeString($ip)
        );

        $cmd = sprintf('sudo -n /usr/bin/sqlite3 -readonly %s %s 2>&1',
            escapeshellarg($db), escapeshellarg($q));
        $out = trim((string)@shell_exec($cmd));

        if ($out === '') {
            return ['permanent' => $fallbackPermanent, 'remaining' => ''];
        }

        [$timeofban, $bantime] = array_pad(explode('|', $out), 2, '0');
        $timeofban = (int)$timeofban;
        $bantime   = (int)$bantime;

        if ($bantime < 0) {
            return ['permanent' => true, 'remaining' => ''];
        }

        $remaining = max(0, ($timeofban + $bantime) - time());
        return [
            'permanent' => false,
            'remaining' => $this->formatRemaining($remaining),
        ];
    }

    private function formatRemaining(int $seconds): string
    {
        if ($seconds <= 0) return 'läuft ab';
        if ($seconds < 60) return "noch {$seconds} Sek.";
        if ($seconds < 3600) return 'noch ' . (int)ceil($seconds / 60) . ' Min.';
        if ($seconds < 86400) return 'noch ' . round($seconds / 3600, 1) . ' Std.';
        return 'noch ' . (int)ceil($seconds / 86400) . ' Tage';
    }

    private function serviceLabel(string $jail): string
    {
        return match(true) {
            $jail === 'sshd'            => 'SSH',
            $jail === 'dovecot'         => 'IMAP/POP3',
            str_starts_with($jail, 'postfix') => 'SMTP',
            str_starts_with($jail, 'nginx')   => 'Web',
            $jail === 'recidive'        => 'Recidive',
            str_contains($jail, 'blacklist') => 'Blacklist',
            default                     => $jail,
        };
    }

    /** Liste aller Jails */
    private function jailList(): array
    {
        $out = $this->f2b('status');
        if (preg_match('/Jail list:\s*(.+)$/mi', $out, $m)) {
            $jails = array_map('trim', preg_split('/\s*,\s*/', trim($m[1])));
            return array_values(array_filter($jails, fn($v) => $v !== ''));
        }
        return [];
    }

    /** fail2ban-client über sudo aufrufen */
    private function f2b(string $args): string
    {
        return (string) @shell_exec('sudo -n /usr/bin/fail2ban-client '.$args.' 2>&1');
    }

    /** Pfad zur Fail2Ban-SQLite-DB holen */
    private function getDbFile(): string
    {
        $out = $this->f2b('get dbfile');
        $lines = array_values(array_filter(array_map('trim', preg_split('/\r?\n/', $out))));
        $path  = end($lines) ?: '';
        $path  = preg_replace('/^`?-?\s*/', '', $path);
        return $path ?: '/var/lib/fail2ban/fail2ban.sqlite3';
    }
}