<?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\Serializer\Mapping\Loader;

use Symfony\Component\Serializer\Attribute\Context;
use Symfony\Component\Serializer\Attribute\DiscriminatorMap;
use Symfony\Component\Serializer\Attribute\Groups;
use Symfony\Component\Serializer\Attribute\Ignore;
use Symfony\Component\Serializer\Attribute\MaxDepth;
use Symfony\Component\Serializer\Attribute\SerializedName;
use Symfony\Component\Serializer\Attribute\SerializedPath;
use Symfony\Component\Serializer\Exception\MappingException;
use Symfony\Component\Serializer\Mapping\AttributeMetadata;
use Symfony\Component\Serializer\Mapping\AttributeMetadataInterface;
use Symfony\Component\Serializer\Mapping\ClassDiscriminatorMapping;
use Symfony\Component\Serializer\Mapping\ClassMetadataInterface;

/**
 * Loader for PHP attributes.
 *
 * @author Kévin Dunglas <dunglas@gmail.com>
 * @author Alexander M. Turek <me@derrabus.de>
 * @author Alexandre Daubois <alex.daubois@gmail.com>
 */
class AttributeLoader implements LoaderInterface
{
    private const KNOWN_ATTRIBUTES = [
        DiscriminatorMap::class,
        Groups::class,
        Ignore::class,
        MaxDepth::class,
        SerializedName::class,
        SerializedPath::class,
        Context::class,
    ];

    /**
     * @param array<class-string, class-string[]> $mappedClasses
     */
    public function __construct(
        private bool $allowAnyClass = true,
        private array $mappedClasses = [],
    ) {
    }

    /**
     * @return class-string[]
     */
    public function getMappedClasses(): array
    {
        return array_keys($this->mappedClasses);
    }

    public function loadClassMetadata(ClassMetadataInterface $classMetadata): bool
    {
        if (!$sourceClasses = $this->mappedClasses[$classMetadata->getName()] ??= $this->allowAnyClass ? [$classMetadata->getName()] : []) {
            return false;
        }

        $success = false;
        foreach ($sourceClasses as $sourceClass) {
            $reflectionClass = $classMetadata->getName() === $sourceClass ? $classMetadata->getReflectionClass() : new \ReflectionClass($sourceClass);
            $success = $this->doLoadClassMetadata($reflectionClass, $classMetadata) || $success;
        }

        return $success;
    }

    private function doLoadClassMetadata(\ReflectionClass $reflectionClass, ClassMetadataInterface $classMetadata): bool
    {
        $className = $reflectionClass->name;
        $loaded = false;
        $classGroups = [];
        $classContextAttribute = null;

        $attributesMetadata = $classMetadata->getAttributesMetadata();

        foreach ($this->loadAttributes($reflectionClass) as $attribute) {
            match (true) {
                $attribute instanceof DiscriminatorMap => $classMetadata->setClassDiscriminatorMapping(new ClassDiscriminatorMapping($attribute->typeProperty, $attribute->mapping, $attribute->defaultType)),
                $attribute instanceof Groups => $classGroups = $attribute->groups,
                $attribute instanceof Context => $classContextAttribute = $attribute,
                default => null,
            };
        }

        foreach ($reflectionClass->getProperties() as $property) {
            if (!isset($attributesMetadata[$property->name])) {
                $attributesMetadata[$property->name] = new AttributeMetadata($property->name);
                $classMetadata->addAttributeMetadata($attributesMetadata[$property->name]);
            }

            $attributeMetadata = $attributesMetadata[$property->name];
            if ($property->getDeclaringClass()->name === $className) {
                if ($classContextAttribute) {
                    $this->setAttributeContextsForGroups($classContextAttribute, $attributeMetadata);
                }

                foreach ($classGroups as $group) {
                    $attributeMetadata->addGroup($group);
                }

                foreach ($this->loadAttributes($property) as $attribute) {
                    $loaded = true;

                    if ($attribute instanceof Groups) {
                        foreach ($attribute->groups as $group) {
                            $attributeMetadata->addGroup($group);
                        }

                        continue;
                    }

                    match (true) {
                        $attribute instanceof MaxDepth => $attributeMetadata->setMaxDepth($attribute->maxDepth),
                        $attribute instanceof SerializedName => $attributeMetadata->setSerializedName($attribute->serializedName),
                        $attribute instanceof SerializedPath => $attributeMetadata->setSerializedPath($attribute->serializedPath),
                        $attribute instanceof Ignore => $attributeMetadata->setIgnore(true),
                        $attribute instanceof Context => $this->setAttributeContextsForGroups($attribute, $attributeMetadata),
                        default => null,
                    };
                }
            }
        }

        foreach ($reflectionClass->getMethods() as $method) {
            if ($method->getDeclaringClass()->name !== $className) {
                continue;
            }
            $name = $method->name;

            if (0 === stripos($name, 'get') && $method->getNumberOfRequiredParameters()) {
                continue; /*  matches the BC behavior in `Symfony\Component\Serializer\Normalizer\ObjectNormalizer::extractAttributes` */
            }

            $accessorOrMutator = match ($name[0]) {
                's' => str_starts_with($name, 'set') && isset($name[$i = 3]),
                'g' => str_starts_with($name, 'get') && isset($name[$i = 3]),
                'h' => str_starts_with($name, 'has') && isset($name[$i = 3]),
                'c' => str_starts_with($name, 'can') && isset($name[$i = 3]),
                'i' => str_starts_with($name, 'is') && isset($name[$i = 2]),
                default => false,
            };
            if ($accessorOrMutator && !ctype_lower($name[$i])) {
                if ($this->hasProperty($method->getDeclaringClass(), $name)) {
                    $attributeName = $name;
                } else {
                    $attributeName = substr($name, $i);

                    if (!$reflectionClass->hasProperty($attributeName)) {
                        $attributeName = lcfirst($attributeName);
                    }
                }

                if (isset($attributesMetadata[$attributeName])) {
                    $attributeMetadata = $attributesMetadata[$attributeName];
                } else {
                    $attributesMetadata[$attributeName] = $attributeMetadata = new AttributeMetadata($attributeName);
                    $classMetadata->addAttributeMetadata($attributeMetadata);
                }
            }

            foreach ($this->loadAttributes($method) as $attribute) {
                if ($attribute instanceof Groups) {
                    if (!$accessorOrMutator) {
                        throw new MappingException(\sprintf('Groups on "%s::%s()" cannot be added. Groups can only be added on methods beginning with "get", "is", "has", "can" or "set".', $className, $method->name));
                    }

                    foreach ($attribute->groups as $group) {
                        $attributeMetadata->addGroup($group);
                    }
                } elseif ($attribute instanceof MaxDepth) {
                    if (!$accessorOrMutator) {
                        throw new MappingException(\sprintf('MaxDepth on "%s::%s()" cannot be added. MaxDepth can only be added on methods beginning with "get", "is", "has", "can" or "set".', $className, $method->name));
                    }

                    $attributeMetadata->setMaxDepth($attribute->maxDepth);
                } elseif ($attribute instanceof SerializedName) {
                    if (!$accessorOrMutator) {
                        throw new MappingException(\sprintf('SerializedName on "%s::%s()" cannot be added. SerializedName can only be added on methods beginning with "get", "is", "has", "can" or "set".', $className, $method->name));
                    }

                    $attributeMetadata->setSerializedName($attribute->serializedName);
                } elseif ($attribute instanceof SerializedPath) {
                    if (!$accessorOrMutator) {
                        throw new MappingException(\sprintf('SerializedPath on "%s::%s()" cannot be added. SerializedPath can only be added on methods beginning with "get", "is", "has", "can" or "set".', $className, $method->name));
                    }

                    $attributeMetadata->setSerializedPath($attribute->serializedPath);
                } elseif ($attribute instanceof Ignore) {
                    if ($accessorOrMutator) {
                        $attributeMetadata->setIgnore(true);
                    }
                } elseif ($attribute instanceof Context) {
                    if (!$accessorOrMutator) {
                        throw new MappingException(\sprintf('Context on "%s::%s()" cannot be added. Context can only be added on methods beginning with "get", "is", "has", "can" or "set".', $className, $method->name));
                    }

                    $this->setAttributeContextsForGroups($attribute, $attributeMetadata);
                }

                $loaded = true;
            }
        }

        return $loaded;
    }

    private function loadAttributes(\ReflectionMethod|\ReflectionClass|\ReflectionProperty $reflector): iterable
    {
        foreach ($reflector->getAttributes() as $attribute) {
            if ($this->isKnownAttribute($attribute->getName())) {
                try {
                    yield $attribute->newInstance();
                } catch (\Error $e) {
                    if (\Error::class !== $e::class) {
                        throw $e;
                    }
                    $on = match (true) {
                        $reflector instanceof \ReflectionClass => ' on class '.$reflector->name,
                        $reflector instanceof \ReflectionMethod => \sprintf(' on "%s::%s()"', $reflector->getDeclaringClass()->name, $reflector->name),
                        $reflector instanceof \ReflectionProperty => \sprintf(' on "%s::$%s"', $reflector->getDeclaringClass()->name, $reflector->name),
                        default => '',
                    };

                    throw new MappingException(\sprintf('Could not instantiate attribute "%s"%s.', $attribute->getName(), $on), 0, $e);
                }
            }
        }
    }

    private function setAttributeContextsForGroups(Context $attribute, AttributeMetadataInterface $attributeMetadata): void
    {
        $context = $attribute->context;
        $groups = $attribute->groups;
        $normalizationContext = $attribute->normalizationContext;
        $denormalizationContext = $attribute->denormalizationContext;

        if ($normalizationContext || $context) {
            $attributeMetadata->setNormalizationContextForGroups($normalizationContext ?: $context, $groups);
        }

        if ($denormalizationContext || $context) {
            $attributeMetadata->setDenormalizationContextForGroups($denormalizationContext ?: $context, $groups);
        }
    }

    private function isKnownAttribute(string $attributeName): bool
    {
        foreach (self::KNOWN_ATTRIBUTES as $knownAttribute) {
            if (is_a($attributeName, $knownAttribute, true)) {
                return true;
            }
        }

        return false;
    }

    private function hasProperty(\ReflectionClass $class, string $propName): bool
    {
        do {
            if ($class->hasProperty($propName)) {
                return true;
            }
        } while ($class = $class->getParentClass());

        return false;
    }
}
