<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

/**
 * CountryZone
 * -----------
 * Stores the zone mapping for a country.
 *
 * Crucial: a country can have DIFFERENT zones for Parcel vs Document.
 * Example from the customer's data:
 *   Afghanistan  →  Parcel Zone 7,  Document Zone 5
 *   Belgium      →  Parcel Zone 1,  Document Zone 3
 *   China        →  Parcel Zone 6,  Document Zone 4
 */
class CountryZone extends Model
{
    protected $table = 'country_zones';

    protected $fillable = [
        'country_name', 'country_iso2', 'parcel_zone', 'document_zone',
    ];

    protected $casts = [
        'parcel_zone'   => 'integer',
        'document_zone' => 'integer',
    ];

    /**
     * Lookup zone for a country by service type.
     * Returns null if country not found OR zone is 0 (origin country).
     */
    public static function lookupZone(string $country, string $serviceType): ?int
    {
        $row = self::where('country_name', $country)->first();
        if (! $row) return null;

        $zone = $serviceType === 'document'
            ? $row->document_zone
            : $row->parcel_zone;

        return ($zone && $zone > 0) ? (int) $zone : null;
    }
}