Proxy

interface Hisobot
{
    public function sarlavha(): string;
    public function tana(): string;
}

final class OgirHisobot implements Hisobot
{
    private string $malumot;

    public function __construct(private readonly string $nom)
    {
        // Konstruktor QIMMAT - bazadan o'qiydi, hisoblaydi
        echo "  [ogir] {$nom} tayyorlanmoqda...", PHP_EOL;
        $qatorlar = [];
        for ($i = 1; $i <= 3; $i++) {
            $qatorlar[] = sprintf('  %d-qator: %d', $i, $i * 1000);
        }
        $this->malumot = implode("\n", $qatorlar);
    }

    public function sarlavha(): string
    {
        return 'Hisobot: ' . $this->nom;
    }

    public function tana(): string
    {
        return $this->malumot;
    }
}

$hisobotlar = [
    new OgirHisobot('yanvar'),
    new OgirHisobot('fevral'),
    new OgirHisobot('mart'),
];

echo '--- royxat', PHP_EOL;
foreach ($hisobotlar as $h) {
    echo $h->sarlavha(), PHP_EOL;
}

final class KechikkanHisobot implements Hisobot
{
    private ?OgirHisobot $haqiqiy = null;

    public function __construct(private readonly string $nom) {}

    // sarlavha uchun haqiqiy obyekt KERAK EMAS
    public function sarlavha(): string
    {
        return 'Hisobot: ' . $this->nom;
    }

    // tana so'ralgandagina yaratamiz
    public function tana(): string
    {
        $this->haqiqiy ??= new OgirHisobot($this->nom);
        return $this->haqiqiy->tana();
    }

    public function yuklanganmi(): bool
    {
        return $this->haqiqiy !== null;
    }
}

$hisobotlar = [
    new KechikkanHisobot('yanvar'),
    new KechikkanHisobot('fevral'),
    new KechikkanHisobot('mart'),
];

echo '--- royxat', PHP_EOL;
foreach ($hisobotlar as $h) {
    echo $h->sarlavha(), PHP_EOL;
}

echo '--- faqat bittasini ochamiz', PHP_EOL;
echo $hisobotlar[1]->tana(), PHP_EOL;

echo '--- yuklanganlar', PHP_EOL;
foreach ($hisobotlar as $h) {
    printf('%-20s %s%s', $h->sarlavha(),
        $h->yuklanganmi() ? 'yuklangan' : 'yuklanmagan', PHP_EOL);
}

final readonly class Foydalanuvchi
{
    public function __construct(
        public string $ism,
        public string $rol,
    ) {}
}

final class HimoyalanganHisobot implements Hisobot
{
    public function __construct(
        private readonly Hisobot $ichki,
        private readonly Foydalanuvchi $kim,
    ) {}

    public function sarlavha(): string
    {
        return $this->ichki->sarlavha();
    }

    public function tana(): string
    {
        if (!in_array($this->kim->rol, ['admin', 'buxgalter'], true)) {
            throw new RuntimeException(
                "{$this->kim->ism} ({$this->kim->rol}) uchun ruxsat yoq"
            );
        }
        return $this->ichki->tana();
    }
}

$asos = new KechikkanHisobot('yanvar');

$kimlar = [
    new Foydalanuvchi('Husanboy', 'admin'),
    new Foydalanuvchi('Malika', 'buxgalter'),
    new Foydalanuvchi('Nodira', 'mehmon'),
];

foreach ($kimlar as $kim) {
    $proxy = new HimoyalanganHisobot($asos, $kim);
    echo '--- ', $kim->ism, ' (', $kim->rol, ')', PHP_EOL;
    echo $proxy->sarlavha(), PHP_EOL;

    try {
        echo $proxy->tana(), PHP_EOL;
    } catch (RuntimeException $x) {
        echo 'RAD ETILDI: ', $x->getMessage(), PHP_EOL;
    }
}

final class SekinBaza
{
    private int $sorovlar = 0;

    public function mahsulot(int $id): string
    {
        $this->sorovlar++;
        echo "    [baza] SELECT ... WHERE id={$id}", PHP_EOL;
        return match ($id) {
            1 => 'Klaviatura',
            2 => 'Sichqoncha',
            default => 'Nomalum',
        };
    }

    public function sorovlar(): int
    {
        return $this->sorovlar;
    }
}

final class KeshProksi
{
    /** @var array<int, string> */
    private array $kesh = [];
    private int $tegdi = 0;

    public function __construct(private readonly SekinBaza $baza) {}

    public function mahsulot(int $id): string
    {
        if (isset($this->kesh[$id])) {
            $this->tegdi++;
            echo "    [kesh] {$id} keshdan", PHP_EOL;
            return $this->kesh[$id];
        }
        return $this->kesh[$id] = $this->baza->mahsulot($id);
    }

    public function statistika(): string
    {
        return sprintf('baza sorovlari: %d, keshdan: %d',
            $this->baza->sorovlar(), $this->tegdi);
    }
}

$baza = new SekinBaza();
$proxy = new KeshProksi($baza);

foreach ([1, 2, 1, 1, 2, 3] as $id) {
    $nom = $proxy->mahsulot($id);
    echo $id, ' -> ', $nom, PHP_EOL;
}

echo $proxy->statistika(), PHP_EOL;

final class UmumiyProksi
{
    /** @var list<string> */
    private array $chaqiruvlar = [];

    public function __construct(private readonly object $ichki) {}

    // istalgan metod chaqiruvi shu yerga tushadi
    public function __call(string $metod, array $argumentlar): mixed
    {
        $this->chaqiruvlar[] = $metod . '(' . implode(', ',
            array_map(static fn(mixed $a): string => var_export($a, true),
                $argumentlar)) . ')';

        return $this->ichki->$metod(...$argumentlar);
    }

    /** @return list<string> */
    public function chaqiruvlar(): array
    {
        return $this->chaqiruvlar;
    }
}

final class Kalkulyator
{
    public function qosh(int $a, int $b): int { return $a + $b; }
    public function kopaytir(int $a, int $b): int { return $a * $b; }
}

$k = new UmumiyProksi(new Kalkulyator());

echo $k->qosh(2, 3), PHP_EOL;
echo $k->kopaytir(4, 5), PHP_EOL;

echo '--- yozib olingan chaqiruvlar', PHP_EOL;
foreach ($k->chaqiruvlar() as $c) {
    echo '  ', $c, PHP_EOL;
}

$jadval = [
    ['Adapter',   'interfeys mos emas', 'tarjima qiladi',      'ha'],
    ['Decorator', 'xulq yetarli emas',  'qoshadi',             'yoq'],
    ['Proxy',     'kirishni nazorat',   'toxtatishi mumkin',   'yoq'],
];

printf("%-11s %-22s %-20s %s%s", 'Naqsh', 'Muammo', 'Nima qiladi',
    'Interfeys ozgaradimi', PHP_EOL);
echo str_repeat('-', 76), PHP_EOL;
foreach ($jadval as $q) {
    printf("%-11s %-22s %-20s %s%s", ...[...$q, PHP_EOL]);
}