<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Validator\Mapping;

use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\Constraints\Cascade;
use Symfony\Component\Validator\Constraints\Composite;
use Symfony\Component\Validator\Constraints\GroupSequence;
use Symfony\Component\Validator\Constraints\Traverse;
use Symfony\Component\Validator\Constraints\Valid;
use Symfony\Component\Validator\Exception\ConstraintDefinitionException;
use Symfony\Component\Validator\Exception\GroupDefinitionException;
use Symfony\Component\Validator\GroupSequenceProviderInterface;

/**
 * Default implementation of {@link ClassMetadataInterface}.
 *
 * This class supports serialization and cloning.
 *
 * @author Bernhard Schussek <bschussek@gmail.com>
 * @author Fabien Potencier <fabien@symfony.com>
 */
class ClassMetadata extends GenericMetadata implements ClassMetadataInterface
{
    private string $name;
    private string $defaultGroup;

    /**
     * @var MemberMetadata[][]
     */
    private array $members = [];

    /**
     * @var PropertyMetadata[]
     */
    private array $properties = [];

    /**
     * @var GetterMetadata[]
     */
    private array $getters = [];

    private ?GroupSequence $groupSequence = null;
    private bool $groupSequenceProvider = false;
    private ?string $groupProvider = null;

    /**
     * The strategy for cascading objects.
     *
     * By default, objects are not cascaded.
     *
     * @var CascadingStrategy::*
     */
    private int $cascadingStrategy = CascadingStrategy::NONE;

    /**
     * The strategy for traversing traversable objects.
     *
     * By default, only instances of {@link \Traversable} are traversed.
     *
     * @var TraversalStrategy::*
     */
    private int $traversalStrategy = TraversalStrategy::IMPLICIT;

    private \ReflectionClass $reflClass;

    public function __construct(string $class)
    {
        $this->name = $class;
        // class name without namespace
        if (false !== $nsSep = strrpos($class, '\\')) {
            $this->defaultGroup = substr($class, $nsSep + 1);
        } else {
            $this->defaultGroup = $class;
        }
    }

    public function __serialize(): array
    {
        return array_filter([
            'cascadingStrategy' => CascadingStrategy::NONE !== $this->cascadingStrategy ? $this->cascadingStrategy : null,
            'traversalStrategy' => TraversalStrategy::IMPLICIT !== $this->traversalStrategy ? $this->traversalStrategy : null,
        ] + parent::__serialize() + [
            'getters' => $this->getters,
            'groupSequence' => $this->groupSequence,
            'groupSequenceProvider' => $this->groupSequenceProvider,
            'groupProvider' => $this->groupProvider,
            'members' => $this->members,
            'name' => $this->name,
            'properties' => $this->properties,
            'defaultGroup' => $this->defaultGroup,
        ]);
    }

    public function getClassName(): string
    {
        return $this->name;
    }

    /**
     * Returns the name of the default group for this class.
     *
     * For each class, the group "Default" is an alias for the group
     * "<ClassName>", where <ClassName> is the non-namespaced name of the
     * class. All constraints implicitly or explicitly assigned to group
     * "Default" belong to both of these groups, unless the class defines
     * a group sequence.
     *
     * If a class defines a group sequence, validating the class in "Default"
     * will validate the group sequence. The constraints assigned to "Default"
     * can still be validated by validating the class in "<ClassName>".
     */
    public function getDefaultGroup(): string
    {
        return $this->defaultGroup;
    }

    /**
     * If the constraint {@link Cascade} is added, the cascading strategy will be
     * changed to {@link CascadingStrategy::CASCADE}.
     *
     * If the constraint {@link Traverse} is added, the traversal strategy will be
     * changed. Depending on the $traverse property of that constraint,
     * the traversal strategy will be set to one of the following:
     *
     *  - {@link TraversalStrategy::IMPLICIT} by default
     *  - {@link TraversalStrategy::NONE} if $traverse is disabled
     *  - {@link TraversalStrategy::TRAVERSE} if $traverse is enabled
     */
    public function addConstraint(Constraint $constraint): static
    {
        $this->checkConstraint($constraint);

        if ($constraint instanceof Traverse) {
            $this->traversalStrategy = $constraint->traverse ? TraversalStrategy::TRAVERSE : TraversalStrategy::NONE;

            // The constraint is not added
            return $this;
        }

        if ($constraint instanceof Cascade) {
            $this->cascadingStrategy = CascadingStrategy::CASCADE;

            foreach ($this->getReflectionClass()->getProperties() as $property) {
                if (isset($constraint->exclude[$property->getName()])) {
                    continue;
                }

                if ($this->canCascade($property->getType())) {
                    $this->addPropertyConstraint($property->getName(), new Valid());
                }
            }

            // The constraint is not added
            return $this;
        }

        $constraint->addImplicitGroupName($this->getDefaultGroup());

        if ($constraint instanceof Valid && null === $constraint->groups) {
            $this->cascadingStrategy = CascadingStrategy::CASCADE;
            $this->traversalStrategy = $constraint->traverse ? TraversalStrategy::IMPLICIT : TraversalStrategy::NONE;

            // The constraint is not added
            return $this;
        }

        parent::addConstraint($constraint);

        return $this;
    }

    /**
     * Adds a constraint to the given property.
     *
     * @return $this
     */
    public function addPropertyConstraint(string $property, Constraint $constraint): static
    {
        if (!isset($this->properties[$property])) {
            $this->properties[$property] = new PropertyMetadata($this->getClassName(), $property);

            $this->addPropertyMetadata($this->properties[$property]);
        }

        $constraint->addImplicitGroupName($this->getDefaultGroup());

        $this->properties[$property]->addConstraint($constraint);

        return $this;
    }

    /**
     * @param Constraint[] $constraints
     *
     * @return $this
     */
    public function addPropertyConstraints(string $property, array $constraints): static
    {
        foreach ($constraints as $constraint) {
            $this->addPropertyConstraint($property, $constraint);
        }

        return $this;
    }

    /**
     * Adds a constraint to the getter of the given property.
     *
     * The name of the getter is assumed to be the name of the property with an
     * uppercased first letter and the prefix "get", "is" or "has".
     *
     * @return $this
     */
    public function addGetterConstraint(string $property, Constraint $constraint): static
    {
        if (!isset($this->getters[$property])) {
            $this->getters[$property] = new GetterMetadata($this->getClassName(), $property);

            $this->addPropertyMetadata($this->getters[$property]);
        }

        $constraint->addImplicitGroupName($this->getDefaultGroup());

        $this->getters[$property]->addConstraint($constraint);

        return $this;
    }

    /**
     * Adds a constraint to the getter of the given property.
     *
     * @return $this
     */
    public function addGetterMethodConstraint(string $property, string $method, Constraint $constraint): static
    {
        if (!isset($this->getters[$property])) {
            $this->getters[$property] = new GetterMetadata($this->getClassName(), $property, $method);

            $this->addPropertyMetadata($this->getters[$property]);
        }

        $constraint->addImplicitGroupName($this->getDefaultGroup());

        $this->getters[$property]->addConstraint($constraint);

        return $this;
    }

    /**
     * @param Constraint[] $constraints
     *
     * @return $this
     */
    public function addGetterConstraints(string $property, array $constraints): static
    {
        foreach ($constraints as $constraint) {
            $this->addGetterConstraint($property, $constraint);
        }

        return $this;
    }

    /**
     * @param Constraint[] $constraints
     *
     * @return $this
     */
    public function addGetterMethodConstraints(string $property, string $method, array $constraints): static
    {
        foreach ($constraints as $constraint) {
            $this->addGetterMethodConstraint($property, $method, $constraint);
        }

        return $this;
    }

    /**
     * Merges the constraints of the given metadata into this object.
     */
    public function mergeConstraints(self $source): void
    {
        if ($source->isGroupSequenceProvider()) {
            $this->setGroupProvider($source->getGroupProvider());
            $this->setGroupSequenceProvider(true);
        }

        if (TraversalStrategy::IMPLICIT === $this->traversalStrategy) {
            $this->traversalStrategy = $source->getTraversalStrategy();
        }

        foreach ($source->getConstraints() as $constraint) {
            $this->addConstraint(clone $constraint);
        }

        foreach ($source->getConstrainedProperties() as $property) {
            foreach ($source->getPropertyMetadata($property) as $member) {
                $member = clone $member;

                foreach ($member->getConstraints() as $constraint) {
                    $constraint->addImplicitGroupName($this->getDefaultGroup());
                    $member->addConstraint($constraint);
                }

                if ($member instanceof MemberMetadata && !$member->isPrivate($this->name)) {
                    $property = $member->getPropertyName();
                    $this->members[$property][] = $member;

                    if ($member instanceof PropertyMetadata && !isset($this->properties[$property])) {
                        $this->properties[$property] = $member;
                    } elseif ($member instanceof GetterMetadata && !isset($this->getters[$property])) {
                        $this->getters[$property] = $member;
                    }
                } else {
                    $this->addPropertyMetadata($member);
                }
            }
        }
    }

    /**
     * Drops the auto-mapping placeholders the loaders left untouched, and moves
     * the remaining ones last, where merging the parent's metadata would have put them.
     *
     * @param array<string, array{PropertyMetadata, int}> $placeholders
     *
     * @internal
     */
    public function removeUnusedAutoMappingPlaceholders(array $placeholders): void
    {
        foreach ($placeholders as $property => [$placeholder, $strategy]) {
            if (!$placeholder->getConstraints() && $strategy === $placeholder->getAutoMappingStrategy() && CascadingStrategy::NONE === $placeholder->getCascadingStrategy()) {
                $this->members[$property] = array_values(array_filter($this->members[$property], static fn (MemberMetadata $member) => $member !== $placeholder));

                if ($placeholder === ($this->properties[$property] ?? null)) {
                    unset($this->properties[$property]);
                }
            }

            $members = $this->members[$property];
            unset($this->members[$property]);

            if ($members) {
                $this->members[$property] = $members;
            }
        }
    }

    public function hasPropertyMetadata(string $property): bool
    {
        return \array_key_exists($property, $this->members);
    }

    public function getPropertyMetadata(string $property): array
    {
        return $this->members[$property] ?? [];
    }

    public function getConstrainedProperties(): array
    {
        return array_keys($this->members);
    }

    /**
     * Sets the default group sequence for this class.
     *
     * @param string[]|GroupSequence $groupSequence An array of group names
     *
     * @return $this
     *
     * @throws GroupDefinitionException
     */
    public function setGroupSequence(array|GroupSequence $groupSequence): static
    {
        if ($this->isGroupSequenceProvider()) {
            throw new GroupDefinitionException('Defining a static group sequence is not allowed with a group sequence provider.');
        }

        if (\is_array($groupSequence)) {
            $groupSequence = new GroupSequence($groupSequence);
        }

        if (\in_array(Constraint::DEFAULT_GROUP, $groupSequence->groups, true)) {
            throw new GroupDefinitionException(\sprintf('The group "%s" is not allowed in group sequences.', Constraint::DEFAULT_GROUP));
        }

        if (!\in_array($this->getDefaultGroup(), $groupSequence->groups, true)) {
            throw new GroupDefinitionException(\sprintf('The group "%s" is missing in the group sequence.', $this->getDefaultGroup()));
        }

        $this->groupSequence = $groupSequence;

        return $this;
    }

    public function hasGroupSequence(): bool
    {
        return isset($this->groupSequence) && $this->groupSequence->groups;
    }

    public function getGroupSequence(): ?GroupSequence
    {
        return $this->groupSequence;
    }

    /**
     * Returns a ReflectionClass instance for this class.
     */
    public function getReflectionClass(): \ReflectionClass
    {
        return $this->reflClass ??= new \ReflectionClass($this->getClassName());
    }

    /**
     * Sets whether a group sequence provider should be used.
     *
     * @throws GroupDefinitionException
     */
    public function setGroupSequenceProvider(bool $active): void
    {
        if ($this->hasGroupSequence()) {
            throw new GroupDefinitionException('Defining a group sequence provider is not allowed with a static group sequence.');
        }

        if (null === $this->groupProvider && !$this->getReflectionClass()->implementsInterface(GroupSequenceProviderInterface::class)) {
            throw new GroupDefinitionException(\sprintf('Class "%s" must implement GroupSequenceProviderInterface.', $this->name));
        }

        $this->groupSequenceProvider = $active;
    }

    public function isGroupSequenceProvider(): bool
    {
        return $this->groupSequenceProvider;
    }

    public function setGroupProvider(?string $provider): void
    {
        $this->groupProvider = $provider;
    }

    public function getGroupProvider(): ?string
    {
        return $this->groupProvider;
    }

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

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

    private function addPropertyMetadata(PropertyMetadataInterface $metadata): void
    {
        $property = $metadata->getPropertyName();

        $this->members[$property][] = $metadata;
    }

    private function checkConstraint(Constraint $constraint): void
    {
        if (!\in_array(Constraint::CLASS_CONSTRAINT, (array) $constraint->getTargets(), true)) {
            throw new ConstraintDefinitionException(\sprintf('The constraint "%s" cannot be put on classes.', get_debug_type($constraint)));
        }

        if ($constraint instanceof Composite) {
            foreach ($constraint->getNestedConstraints() as $nestedConstraint) {
                $this->checkConstraint($nestedConstraint);
            }
        }
    }

    private function canCascade(?\ReflectionType $type = null): bool
    {
        if (null === $type) {
            return false;
        }

        if ($type instanceof \ReflectionIntersectionType) {
            foreach ($type->getTypes() as $nestedType) {
                if ($this->canCascade($nestedType)) {
                    return true;
                }
            }

            return false;
        }

        if ($type instanceof \ReflectionUnionType) {
            foreach ($type->getTypes() as $nestedType) {
                if (!$this->canCascade($nestedType)) {
                    return false;
                }
            }

            return true;
        }

        return $type instanceof \ReflectionNamedType && (\in_array($type->getName(), ['array', 'null'], true) || class_exists($type->getName()));
    }
}
