<?php

namespace App\Domains\Ticketing\Ticket\Services;

use Carbon\CarbonImmutable;
use DateTimeZone;
use Illuminate\Support\Facades\DB;
use InvalidArgumentException;

class ConvertValidityTimesToUtcService
{
    /**
     * IDs or the all flag select values the operator has confirmed are still local.
     * UTC cannot be inferred reliably from a timezone-less database timestamp.
     *
     * @param  array<int, int>  $ids
     * @return array<int, array<string, mixed>>
     */
    public function run(array $ids, string $timezone, bool $apply = false, bool $all = false): array
    {
        if (! in_array($timezone, DateTimeZone::listIdentifiers(DateTimeZone::ALL_WITH_BC), true)) {
            throw new InvalidArgumentException('Zona horaria de origen inválida.');
        }
        if ($all && $ids !== []) {
            throw new InvalidArgumentException('Usar --all o --ids, no ambos.');
        }
        if (! $all && $ids === []) {
            throw new InvalidArgumentException('Indicar --all para todos los fixed_window o --ids para una selección.');
        }

        return DB::transaction(function () use ($ids, $timezone, $apply): array {
            $query = DB::table('validity_times')->orderBy('id');
            if ($ids === []) {
                $query->where('type', 'fixed_window');
            } else {
                $query->whereIn('id', $ids);
            }
            if ($apply) {
                $query->lockForUpdate();
            }
            $rows = $query->get();
            if ($ids !== [] && $rows->count() !== count(array_unique($ids))) {
                throw new InvalidArgumentException('Uno o más IDs no existen. No se modificó ningún registro.');
            }
            if ($rows->contains(fn ($row): bool => $row->type !== 'fixed_window')) {
                throw new InvalidArgumentException('Sólo se admiten IDs de fixed_window. No se modificó ningún registro.');
            }
            $result = [];
            foreach ($rows as $row) {
                $start = $this->convert($row->fixed_starts_at, $timezone);
                $end = $this->convert($row->fixed_expires_at, $timezone);
                $result[] = [
                    'id' => $row->id,
                    'status' => $apply ? 'convertido' : 'propuesta; verificar origen local',
                    'original_start' => $row->fixed_starts_at,
                    'original_end' => $row->fixed_expires_at,
                    'utc_start' => $start,
                    'utc_end' => $end,
                ];
                if (! $apply) {
                    continue;
                }
                DB::table('validity_times')->where('id', $row->id)->update([
                    'fixed_starts_at' => $start,
                    'fixed_expires_at' => $end,
                ]);
            }

            return $result;
        });
    }

    private function convert(?string $value, string $timezone): ?string
    {
        return $value === null ? null : CarbonImmutable::parse($value, $timezone)->utc()->format('Y-m-d H:i:s');
    }
}