<?php

namespace App\Services\Hosting\Proxmox;

use App\Enums\VmPowerAction;
use App\Exceptions\Hosting\ProxmoxException;
use App\Exceptions\Hosting\ProvisioningException;
use App\Models\Customer;
use App\Models\User;
use App\Models\VmActivityLog;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Str;

class VmManagementService
{
    public function __construct(
        private readonly ProxmoxClient $proxmox,
    ) {}

    public function assertManageable(Customer $vm): void
    {
        if (! $vm->vmid) {
            throw new ProvisioningException('VM ist noch nicht in Proxmox provisioniert.', step: 'vm_not_ready');
        }

        if ($vm->status !== 'active') {
            throw new ProvisioningException('VM ist nicht aktiv (Status: '.$vm->status.').', step: 'vm_not_active');
        }
    }

    public function refreshLiveStatus(Customer $vm): array
    {
        $this->assertManageable($vm);

        $raw = $this->proxmox->getVMStatus((int) $vm->vmid);
        $normalized = $this->proxmox->normalizeLiveStatus($raw);

        $vm->update([
            'proxmox_status' => $normalized['status'],
            'proxmox_uptime' => $normalized['uptime'],
            'proxmox_status_at' => now(),
        ]);

        return $normalized;
    }

    public function power(Customer $vm, VmPowerAction $action, User $user): void
    {
        $this->assertManageable($vm);

        $live = $this->refreshLiveStatus($vm);
        $isRunning = ($live['status'] ?? '') === 'running';

        if ($action->requiresRunning() && ! $isRunning) {
            throw new ProxmoxException('VM läuft nicht – Aktion nicht möglich.', step: 'power_state');
        }

        if ($action->requiresStopped() && $isRunning) {
            throw new ProxmoxException('VM läuft bereits.', step: 'power_state');
        }

        try {
            match ($action) {
                VmPowerAction::Start => $this->proxmox->startVM((int) $vm->vmid),
                VmPowerAction::Shutdown => $this->proxmox->shutdownVM((int) $vm->vmid),
                VmPowerAction::Stop => $this->proxmox->stopVM((int) $vm->vmid),
                VmPowerAction::Reboot => $this->proxmox->rebootVM((int) $vm->vmid),
                VmPowerAction::Reset => $this->proxmox->resetVM((int) $vm->vmid),
            };

            $this->log($vm, $user, 'power.'.$action->value, 'success');
            $this->refreshLiveStatus($vm);
        } catch (\Throwable $e) {
            $this->log($vm, $user, 'power.'.$action->value, 'failed', $e->getMessage());
            throw $e;
        }
    }

    public function mountIso(Customer $vm, string $isoVolid, User $user): void
    {
        $this->assertManageable($vm);

        $available = collect($this->proxmox->listIsos())->pluck('volid');
        if (! $available->contains($isoVolid)) {
            throw new ProxmoxException('ISO nicht im Storage gefunden.', step: 'iso_invalid');
        }

        try {
            $this->proxmox->mountIso((int) $vm->vmid, $isoVolid);
            $vm->update(['attached_iso' => $isoVolid]);
            $this->log($vm, $user, 'iso.mount', 'success', null, ['iso' => $isoVolid]);
        } catch (\Throwable $e) {
            $this->log($vm, $user, 'iso.mount', 'failed', $e->getMessage());
            throw $e;
        }
    }

    public function unmountIso(Customer $vm, User $user): void
    {
        $this->assertManageable($vm);

        try {
            $this->proxmox->unmountIso((int) $vm->vmid);
            $vm->update(['attached_iso' => null]);
            $this->log($vm, $user, 'iso.unmount', 'success');
        } catch (\Throwable $e) {
            $this->log($vm, $user, 'iso.unmount', 'failed', $e->getMessage());
            throw $e;
        }
    }

    /**
     * @return array{token: string, ws_url: string, vmid: int, node: string, expires_at: int}
     */
    public function createConsoleSession(Customer $vm, User $user): array
    {
        $this->assertManageable($vm);

        $live = $this->refreshLiveStatus($vm);
        if (($live['status'] ?? '') !== 'running') {
            throw new ProxmoxException('Konsole nur bei laufender VM verfügbar. Bitte VM starten.', step: 'console_not_running');
        }

        $proxy = $this->proxmox->createVncProxy((int) $vm->vmid);

        if ($proxy['port'] === '' || $proxy['ticket'] === '') {
            throw new ProxmoxException('VNC-Proxy konnte nicht erstellt werden.', step: 'console_proxy');
        }

        $token = Str::random(64);
        $proxmoxWsUrl = $this->proxmox->buildVncWebSocketUrl((int) $vm->vmid, $proxy['port'], $proxy['ticket']);
        $expiresAt = now()->addMinutes(5)->timestamp;

        $wsUrl = $proxmoxWsUrl;
        if (config('hosting.console.proxy_enabled') && config('hosting.console.proxy_ws_url')) {
            $wsUrl = rtrim(config('hosting.console.proxy_ws_url'), '/').'/'.$token;
        }

        Cache::put($this->consoleCacheKey($token), [
            'customer_id' => $vm->id,
            'user_id' => $user->id,
            'ws_url' => $proxmoxWsUrl,
            'ticket' => $proxy['ticket'],
            'port' => $proxy['port'],
            'vmid' => $vm->vmid,
            'node' => $proxy['node'],
            'cert' => $proxy['cert'],
        ], 300);

        $this->log($vm, $user, 'console.open', 'success');

        return [
            'token' => $token,
            'ws_url' => $wsUrl,
            'vmid' => (int) $vm->vmid,
            'node' => $proxy['node'],
            'expires_at' => $expiresAt,
        ];
    }

    public function getConsoleSession(string $token, User $user): array
    {
        $data = Cache::get($this->consoleCacheKey($token));

        if (! $data) {
            throw new ProxmoxException('Konsole-Session abgelaufen oder ungültig.', step: 'console_expired');
        }

        if ($data['user_id'] !== $user->id && ! $user->isAdmin()) {
            throw new ProxmoxException('Kein Zugriff auf diese Konsole.', step: 'console_forbidden');
        }

        return $data;
    }

    public function consoleCacheKey(string $token): string
    {
        return 'vm_console:'.$token;
    }

    private function log(Customer $vm, User $user, string $action, string $status, ?string $message = null, array $meta = []): void
    {
        VmActivityLog::query()->create([
            'customer_id' => $vm->id,
            'user_id' => $user->id,
            'action' => $action,
            'status' => $status,
            'message' => $message,
            'meta' => $meta ?: null,
        ]);
    }
}