<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Support\Carbon;
use Illuminate\Support\Str;

/**
 * One-time, time-limited link that lets an Abo owner (customer) update their credit card
 * via PAYONE without logging in. The plaintext token lives only in the e-mail link; the
 * database stores a SHA-256 hash for an indexed O(1) lookup (never bcrypt – that would
 * forbid a direct lookup). Single-use via {@see $used_at}, TTL via {@see ttlHours()}.
 *
 * @property int $user_abo_id
 * @property string $token_hash
 * @property Carbon $expires_at
 * @property Carbon|null $used_at
 * @property int|null $created_by_user_id
 */
class AboCardUpdateLink extends Model
{
    protected $table = 'abo_card_update_links';

    protected $fillable = [
        'user_abo_id',
        'token_hash',
        'expires_at',
        'used_at',
        'created_by_user_id',
    ];

    protected $casts = [
        'expires_at' => 'datetime',
        'used_at' => 'datetime',
    ];

    public const DEFAULT_TTL_HOURS = 72;

    public function user_abo(): BelongsTo
    {
        return $this->belongsTo(UserAbo::class, 'user_abo_id');
    }

    public static function ttlHours(): int
    {
        $hours = (int) Setting::getContentBySlug('abo-card-update-link-ttl-hours');

        return $hours > 0 ? $hours : self::DEFAULT_TTL_HOURS;
    }

    public static function hashToken(string $token): string
    {
        return hash('sha256', $token);
    }

    /**
     * Creates a link and returns the model plus the plaintext token (only emitted here,
     * never persisted).
     *
     * @return array{0: self, 1: string}
     */
    public static function generateFor(UserAbo $abo, ?int $createdBy = null): array
    {
        $token = Str::random(48);

        $link = self::create([
            'user_abo_id' => $abo->id,
            'token_hash' => self::hashToken($token),
            'expires_at' => now()->addHours(self::ttlHours()),
            'created_by_user_id' => $createdBy,
        ]);

        return [$link, $token];
    }

    public function isRedeemable(): bool
    {
        return $this->used_at === null && $this->expires_at->isFuture();
    }
}