<?php

declare(strict_types=1);

namespace Pdp;

use Stringable;

use function count;
use function is_bool;

final class ResolvedDomain implements ResolvedDomainName
{
    private readonly DomainName $domain;
    private readonly DomainName $secondLevelDomain;
    private readonly DomainName $registrableDomain;
    private readonly DomainName $subDomain;
    private readonly EffectiveTopLevelDomain $suffix;

    /**
     * @throws CannotProcessHost
     */
    private function __construct(
        DomainName $domain,
        EffectiveTopLevelDomain $suffix
    ) {
        $this->domain = $domain;
        $this->suffix = $suffix;
        [
            'registrableDomain' => $this->registrableDomain,
            'secondLevelDomain' => $this->secondLevelDomain,
            'subDomain' => $this->subDomain,
        ] = $this->parse();
    }

    /**
     * @throws CannotProcessHost
     */
    public static function fromICANN(DomainNameProvider|Host|Stringable|string|int|null $domain, int $suffixLength): self
    {
        $domain = self::setDomainName($domain);

        return new self($domain, Suffix::fromICANN($domain->withoutRootLabel()->slice(0, $suffixLength)));
    }

    /**
     * @throws CannotProcessHost
     */
    public static function fromPrivate(DomainNameProvider|Host|Stringable|string|int|null $domain, int $suffixLength): self
    {
        $domain = self::setDomainName($domain);

        return new self($domain, Suffix::fromPrivate($domain->withoutRootLabel()->slice(0, $suffixLength)));
    }

    /**
     * @throws CannotProcessHost
     */
    public static function fromIANA(DomainNameProvider|Host|Stringable|string|int|null $domain): self
    {
        $domain = self::setDomainName($domain);

        return new self($domain, Suffix::fromIANA($domain->withoutRootLabel()->label(0)));
    }

    /**
     * @throws CannotProcessHost
     */
    public static function fromUnknown(DomainNameProvider|Host|Stringable|string|int|null $domain, int $suffixLength = 0): self
    {
        $domain = self::setDomainName($domain);

        return new self($domain, Suffix::fromUnknown($domain->slice(0, $suffixLength)));
    }

    /**
     * @param array{domain:DomainName, suffix:EffectiveTopLevelDomain} $properties
     *
     * @throws CannotProcessHost
     */
    public static function __set_state(array $properties): self
    {
        return new self($properties['domain'], $properties['suffix']);
    }

    /**
     * @throws CannotProcessHost
     */
    private static function setDomainName(DomainNameProvider|Host|Stringable|string|int|null $domain): DomainName
    {
        return match (true) {
            $domain instanceof DomainNameProvider => $domain->domain(),
            $domain instanceof DomainName => $domain,
            default => RegisteredName::fromIDNA2008($domain),
        };
    }

    /**
     * Make sure the Value Object is always in a valid state.
     *
     * @throws UnableToResolveDomain|CannotProcessHost If the suffix can not be attached to the domain
     *
     * @return array{registrableDomain: DomainName, secondLevelDomain: DomainName, subDomain: DomainName}
     */
    private function parse(): array
    {
        $suffixValue = $this->suffix->value();
        if (null === $suffixValue) {
            $nullDomain = $this->domain->clear();

            return [
                'registrableDomain' => $nullDomain,
                'secondLevelDomain' => $nullDomain,
                'subDomain' => $nullDomain,
            ];
        }

        if (2 > count($this->domain)) {
            throw UnableToResolveDomain::dueToUnresolvableDomain($this->domain);
        }

        if ($this->domain->value() === $suffixValue) {
            throw UnableToResolveDomain::dueToIdenticalValue($this->domain);
        }

        $length = count($this->suffix);
        $offset = 0;
        if ($this->domain->isAbsolute()) {
            $offset = 1;
        }

        return [
            'registrableDomain' => $this->domain->slice($offset, $length + 1),
            'secondLevelDomain' => $this->domain->slice($length + $offset, 1),
            'subDomain' => RegisteredName::fromIDNA2008($this->domain->value())->slice($length + 1 + $offset),
        ];
    }

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

    public function domain(): DomainName
    {
        return $this->domain;
    }

    public function registrableDomain(): DomainName
    {
        return $this->registrableDomain;
    }

    public function secondLevelDomain(): DomainName
    {
        return $this->secondLevelDomain;
    }

    public function subDomain(): DomainName
    {
        return $this->subDomain;
    }

    public function suffix(): EffectiveTopLevelDomain
    {
        return $this->suffix;
    }

    public function jsonSerialize(): ?string
    {
        return $this->domain->jsonSerialize();
    }

    public function value(): ?string
    {
        return $this->domain->value();
    }

    public function toString(): string
    {
        return $this->domain->toString();
    }

    public function toAscii(): self
    {
        return new self($this->domain->toAscii(), $this->suffix->toAscii());
    }

    public function toUnicode(): self
    {
        return new self($this->domain->toUnicode(), $this->suffix->toUnicode());
    }

    public function isAbsolute(): bool
    {
        return $this->domain->isAbsolute();
    }

    public function withoutRootLabel(): self
    {
        return new self($this->domain->withoutRootLabel(), $this->suffix);
    }

    public function withRootLabel(): self
    {
        return new self($this->domain->withRootLabel(), $this->suffix);
    }

    /**
     * @throws CannotProcessHost
     */
    public function withSuffix(DomainNameProvider|Host|Stringable|string|int|null $suffix): self
    {
        if (!$suffix instanceof EffectiveTopLevelDomain) {
            $suffix = Suffix::fromUnknown($suffix);
        }

        $domain = $this->domain->withoutRootLabel()->slice(count($this->suffix))->append($suffix);

        return new self(
            $domain->when($this->domain->isAbsolute(), fn (DomainName $domainName) => $domain->withRootLabel()),
            $suffix->normalize($this->domain)
        );
    }

    /**
     * @throws CannotProcessHost|UnableToResolveDomain
     */
    public function withSubDomain(DomainNameProvider|Host|Stringable|string|int|null $subDomain): self
    {
        if (null === $this->suffix->value()) {
            throw UnableToResolveDomain::dueToMissingRegistrableDomain($this->domain);
        }

        $subDomain = RegisteredName::fromIDNA2008($subDomain);
        if ($subDomain->isAbsolute()) {
            $subDomain = $subDomain->withoutRootLabel();
            if (null === $subDomain->value()) {
                throw SyntaxError::dueToMalformedValue($subDomain->withRootLabel()->toString());
            }
        }

        if ($this->subDomain->value() === $subDomain->value()) {
            return $this;
        }

        $domain = $this->registrableDomain->prepend($subDomain);

        return new self($domain->when($this->domain->isAbsolute(), fn (DomainName $domainName) => $domain->withRootLabel()), $this->suffix);
    }

    /**
     * @throws CannotProcessHost|UnableToResolveDomain
     */
    public function withSecondLevelDomain(DomainNameProvider|Host|Stringable|string|int|null $label): self
    {
        if (null === $this->suffix->value()) {
            throw UnableToResolveDomain::dueToMissingRegistrableDomain($this->domain);
        }

        $label = RegisteredName::fromIDNA2008($label);
        if ($label->isAbsolute()) {
            if (2 !== count($label)) {
                throw UnableToResolveDomain::dueToInvalidSecondLevelDomain($label);
            }
            $label = $label->withoutRootLabel();
        }

        if (1 !== count($label)) {
            throw UnableToResolveDomain::dueToInvalidSecondLevelDomain($label);
        }

        $newRegistrableDomain = $this->registrableDomain->withoutLabel(-1)->prepend($label);
        if ($newRegistrableDomain->value() === $this->registrableDomain->value()) {
            return $this;
        }

        return new self($newRegistrableDomain->prepend($this->subDomain), $this->suffix);
    }

    /**
     * Apply the callback if the given "condition" is (or resolves to) true.
     *
     * @param (callable($this): bool)|bool $condition
     * @param callable($this): (self|null) $onSuccess
     * @param ?callable($this): (self|null) $onFail
     *
     */
    public function when(callable|bool $condition, callable $onSuccess, ?callable $onFail = null): self
    {
        if (!is_bool($condition)) {
            $condition = $condition($this);
        }

        return match (true) {
            $condition => $onSuccess($this),
            null !== $onFail => $onFail($this),
            default => $this,
        } ?? $this;
    }
}