<?php

declare(strict_types=1);

namespace App\Services\VirtualMachine;

use App\Models\OrderItem;
use App\Models\Os;
use App\Services\VirtualMachine\Dto\VmInfrastructureContext;
use RuntimeException;

/**
 * Resolves the provisioning target by walking the ACTIVE chain:
 *
 *   active vCenter → active Datacenter → active Host → active Datastore + Network
 *
 * The OS host (and its datacenter) overrides the active host when set, because the
 * OS template, datastore, network, resource pool and folder belong to that host. Datastore, network, resource pool and folder are exceptions: if
 * the OS has datastore_id / module_network_id / resource_pool_id / folder_id
 * set, they override the active chain / global default (an OS can target a
 * different datastore/IP pool/resource pool/folder than whatever happens to
 * be "active" or configured as the system-wide default).
 */
class VmInfrastructureResolver
{
    public function __construct(
        private readonly VmProvisionLogger $logger,
        private readonly VmActiveProviderService $activeProvider,
        private readonly VmProviderSettingsService $providerSettings,
    ) {
    }

    public function resolve(OrderItem $item, $product): VmInfrastructureContext
    {
        $os = Os::with(['osGroup', 'host.datacenter', 'network', 'datastore', 'resourcePool', 'folder'])->find($item->os_id);

        if (!$os) {
            throw new RuntimeException(
                "Không tìm thấy OS id={$item->os_id} trong OrderItem #{$item->id}. os_id không hợp lệ."
            );
        }

        $chain         = $this->activeProvider->resolveChain();
        $host          = $os->host ?? $chain['host'];
        $datacenter    = $os->host?->datacenter ?? $chain['datacenter'];
        $network       = $os->network ?? $chain['network'];
        $datastore     = $os->datastore ?? $chain['datastore'];
        $folderId      = $os->folder?->folder ?? $this->providerSettings->defaultFolder();
        $resourcePoolId = $os->resourcePool?->resource_pool ?? $this->providerSettings->defaultResourcePool();

        $this->logger->step('Infrastructure resolved from active chain', [
            'order_item_id'          => $item->id,
            'vcenter_id'             => $chain['vcenter']->id,
            'datacenter_id'          => $chain['datacenter']->id,
            'host_id'                => $host->id,
            'host_from_os'           => $os->host !== null,
            'datastore_id'           => $datastore->id,
            'datastore_from_os'      => $os->datastore !== null,
            'network_id'             => $network->id,
            'network_from_os'        => $os->network !== null,
            'folder_id'              => $folderId,
            'folder_from_os'         => $os->folder !== null,
            'resource_pool_id'       => $resourcePoolId,
            'resource_pool_from_os'  => $os->resourcePool !== null,
        ]);

        $osGroupName = $os->osGroup?->name ?? '';
        $isWindows   = str_contains(strtolower($osGroupName), 'windows');

        return new VmInfrastructureContext(
            os:         $os,
            host:       $host,
            datacenter: $datacenter,
            vcenter:    $chain['vcenter'],
            template:   $os->template_id,
            isWindows:  $isWindows,
            vmUser:     $isWindows ? 'administrator' : 'root',
            vmPort:     $isWindows ? 3389 : 22,
            datastore:  $datastore,
            network:    $network,
            folderId:       $folderId,
            resourcePoolId: $resourcePoolId,
        );
    }
}