<?php

namespace App\Domains\Ticket\Services;

use App\Domains\Auth\Models\User;
use App\Domains\Authorization\Enums\RoleCode;
use App\Domains\Catalog\Enums\CatalogItemType;
use App\Domains\Catalog\Models\CatalogItem;
use App\Domains\Catalog\Models\Variant;
use App\Domains\Tenant\Models\Tenant;
use Illuminate\Support\Collection;
use Illuminate\Support\Str;
use InvalidArgumentException;

class LoadTestTicketDatasetService
{
    public function __construct(
        private readonly TicketGeneratorService $ticketGenerator,
        private readonly TicketValidityResolver $validityResolver,
    ) {}

    /**
     * @return array{
     *     run_id: string,
     *     tenant_code: string,
     *     catalog_item_id: int,
     *     variant_id: int|null,
     *     tickets: int,
     *     scanners: int,
     *     owners: int,
     *     rows: array<int, array{scanner_token: string, ticket_uuid: string, expected_status: int}>
     * }
     */
    public function prepare(
        string $tenantCode,
        int $ticketCount,
        int $scannerCount,
        int $ownerCount,
        ?int $catalogItemId = null,
        ?int $variantId = null,
        ?string $runId = null,
    ): array {
        $this->validateInput($tenantCode, $ticketCount, $scannerCount, $ownerCount);

        $tenant = Tenant::query()->where('codigo', $tenantCode)->firstOrFail();
        $catalogItem = $this->resolveCatalogItem($tenant, $catalogItemId);
        $variant = $this->resolveVariant($catalogItem, $variantId);
        $runId ??= now()->format('Ymd-His').'-'.Str::lower(Str::random(6));

        if (preg_match('/\A[a-zA-Z0-9][a-zA-Z0-9._-]{0,63}\z/', $runId) !== 1) {
            throw new InvalidArgumentException('run_id contiene caracteres inválidos o es demasiado largo.');
        }

        if ($variant !== null && ! $this->validityResolver->resolveVariant($variant)->isValid()) {
            throw new InvalidArgumentException(
                'La variante seleccionada no tiene una vigencia activa y resoluble.'
            );
        }

        $scanners = $this->scanners($tenant, $catalogItem, $scannerCount);
        $owners = $this->owners($tenant, $ownerCount);
        $tokens = $scanners->map(function (User $scanner): string {
            $scanner->tokens()->where('name', 'load-test-scanner')->delete();

            return $scanner->createToken(
                'load-test-scanner',
                ['scanner'],
                now()->addMinutes((int) config('sanctum.expiration', 720)),
            )->plainTextToken;
        })->values();

        $rows = [];
        $remaining = $ticketCount;
        $ownerIndex = 0;
        $scannerIndex = 0;
        $batchSize = min(500, max(1, (int) ceil($ticketCount / $ownerCount)));

        while ($remaining > 0) {
            $quantity = min($batchSize, $remaining);
            $owner = $owners[$ownerIndex % $owners->count()];
            $tickets = $this->ticketGenerator->generate(
                $catalogItem,
                $owner,
                $quantity,
                $variant?->getKey(),
            );

            foreach ($tickets as $ticket) {
                if (! $ticket->is_valid) {
                    throw new InvalidArgumentException(
                        'La configuración seleccionada genera tickets que no están vigentes.'
                    );
                }

                $rows[] = [
                    'scanner_token' => $tokens[$scannerIndex % $tokens->count()],
                    'ticket_uuid' => $ticket->ticket,
                    'expected_status' => 200,
                ];
                $scannerIndex++;
            }

            $remaining -= $quantity;
            $ownerIndex++;
        }

        return [
            'run_id' => $runId,
            'tenant_code' => $tenant->codigo,
            'catalog_item_id' => $catalogItem->getKey(),
            'variant_id' => $variant?->getKey(),
            'tickets' => count($rows),
            'scanners' => $scanners->count(),
            'owners' => $owners->count(),
            'rows' => $rows,
        ];
    }

    private function validateInput(
        string $tenantCode,
        int $ticketCount,
        int $scannerCount,
        int $ownerCount,
    ): void {
        if (! str_starts_with($tenantCode, 'loadtest-')) {
            throw new InvalidArgumentException('El tenant debe comenzar con `loadtest-`.');
        }

        foreach ([
            'tickets' => [$ticketCount, 100_000],
            'scanners' => [$scannerCount, 10_000],
            'owners' => [$ownerCount, 100_000],
        ] as $name => [$value, $maximum]) {
            if ($value < 1 || $value > $maximum) {
                throw new InvalidArgumentException("{$name} debe estar entre 1 y {$maximum}.");
            }
        }

        if ($scannerCount > $ticketCount || $ownerCount > $ticketCount) {
            throw new InvalidArgumentException(
                'La cantidad de scanners y propietarios no puede superar la cantidad de tickets.'
            );
        }
    }

    private function resolveCatalogItem(Tenant $tenant, ?int $catalogItemId): CatalogItem
    {
        $query = $tenant->catalogItems()
            ->where('has_tickets', true)
            ->where('type', CatalogItemType::Standard->value);

        if ($catalogItemId !== null) {
            $query->whereKey($catalogItemId);
        }

        $catalogItem = $query->first();

        if ($catalogItem === null) {
            throw new InvalidArgumentException(
                'No se encontró un producto estándar con tickets habilitados para el tenant.'
            );
        }

        if ($tenant->requiresScannerCategoryValidation() && $catalogItem->category_id === null) {
            throw new InvalidArgumentException(
                'El producto debe tener una categoría para autorizar a los scanners.'
            );
        }

        return $catalogItem;
    }

    private function resolveVariant(CatalogItem $catalogItem, ?int $variantId): ?Variant
    {
        if ($variantId === null) {
            return null;
        }

        $variant = $catalogItem->variants()->whereKey($variantId)->first();

        if ($variant === null) {
            throw new InvalidArgumentException('La variante no pertenece al producto seleccionado.');
        }

        return $variant;
    }

    /** @return Collection<int, User> */
    private function scanners(Tenant $tenant, CatalogItem $catalogItem, int $count): Collection
    {
        return Collection::times($count, function (int $number) use ($tenant, $catalogItem): User {
            $scanner = User::withTrashed()->updateOrCreate(
                ['email' => $this->email($tenant, 'scanner', $number)],
                [
                    'nombre_apellido' => "Load test scanner {$number}",
                    'password' => Str::password(32),
                    'rol_codigo' => RoleCode::Scanner->value,
                    'tenant_codigo' => $tenant->codigo,
                ],
            );
            $scanner->restore();

            if ($tenant->requiresScannerCategoryValidation()) {
                $scanner->scanCategories()->syncWithoutDetaching([$catalogItem->category_id]);
            }

            return $scanner;
        });
    }

    /** @return Collection<int, User> */
    private function owners(Tenant $tenant, int $count): Collection
    {
        return Collection::times($count, function (int $number) use ($tenant): User {
            $owner = User::withTrashed()->updateOrCreate(
                ['email' => $this->email($tenant, 'owner', $number)],
                [
                    'nombre_apellido' => "Load test owner {$number}",
                    'password' => Str::password(32),
                    'rol_codigo' => RoleCode::User->value,
                    'tenant_codigo' => $tenant->codigo,
                ],
            );
            $owner->restore();

            return $owner;
        });
    }

    private function email(Tenant $tenant, string $kind, int $number): string
    {
        $tenantSlug = Str::lower(preg_replace('/[^a-z0-9]+/i', '-', $tenant->codigo));

        return "loadtest+{$tenantSlug}.{$kind}.{$number}@shopit.test";
    }
}