<?php

declare(strict_types=1);

/**
 * SPDX-FileCopyrightText: Sebastian Krupinski <krupinski01@gmail.com>
 * SPDX-License-Identifier: AGPL-3.0-or-later
 */

namespace KTXM\DocumentsManager\Controllers;

use InvalidArgumentException;
use KTXC\Http\Response\JsonResponse;
use KTXC\Http\Response\Response;
use KTXC\Http\Response\StreamedNdJsonResponse;
use KTXC\SessionIdentity;
use KTXC\SessionTenant;
use KTXF\Controller\ControllerAbstract;
use KTXF\Json\JsonSerializable;
use KTXF\Resource\Identifier\CollectionIdentifier;
use KTXF\Resource\Identifier\EntityIdentifier;
use KTXF\Resource\Identifier\ResourceIdentifier;
use KTXF\Resource\Identifier\ResourceIdentifiers;
use KTXF\Resource\Identifier\ServiceIdentifier;
use KTXF\Routing\Attributes\AuthenticatedRoute;
use KTXM\DocumentsManager\Manager;
use KTXM\DocumentsManager\Stream\ExpectedTotal;
use Psr\Log\LoggerInterface;
use Throwable;

class DefaultController extends ControllerAbstract {

    private const ERR_MISSING_PROVIDER = 'Missing parameter: provider';
    private const ERR_MISSING_IDENTIFIER = 'Missing parameter: identifier';
    private const ERR_MISSING_SERVICE = 'Missing parameter: service';
    private const ERR_MISSING_DATA = 'Missing parameter: data';
    private const ERR_MISSING_SOURCES = 'Missing parameter: sources';
    private const ERR_MISSING_SOURCE = 'Missing parameter: source';
    private const ERR_MISSING_TARGET = 'Missing parameter: target';
    private const ERR_MISSING_TARGETS = 'Missing parameter: targets';
    private const ERR_INVALID_OPERATION = 'Invalid operation: ';
    private const ERR_INVALID_PROVIDER = 'Invalid parameter: provider must be a string';
    private const ERR_INVALID_SERVICE = 'Invalid parameter: service must be a string';
    private const ERR_INVALID_IDENTIFIER = 'Invalid parameter: identifier must be a string';
    private const ERR_INVALID_SOURCES = 'Invalid parameter: sources must be an array';
    private const ERR_INVALID_SOURCE = 'Invalid parameter: source must be a string';
    private const ERR_INVALID_TARGET = 'Invalid parameter: target must be a string';
    private const ERR_INVALID_TARGETS = 'Invalid parameter: targets must be an array';
    private const ERR_INVALID_DATA = 'Invalid parameter: data must be an array';
    private const ERR_TARGET_COLLECTION = 'Invalid parameter: target must be provider:service:collection';
    private const ERR_TARGET_ENTITY = 'Invalid parameter: target must be provider:service:collection:entity';

    public function __construct(
        private readonly SessionTenant $tenantIdentity,
        private readonly SessionIdentity $userIdentity,
        private readonly Manager $manager,
        private readonly LoggerInterface $logger
    ) {}

    /**
     * Main API endpoint for documents operations
     *
     * Single operation:
     *   {
     *     "version": 1,
     *     "transaction": "tx-1",
     *     "operation": "entity.create",
     *     "data": {...}
     *   }
     *
     * @return Response
     */
    #[AuthenticatedRoute('/v1', name: 'documents.manager.v1', methods: ['POST'])]
    public function index(
        int $version,
        string $transaction,
        string|null $operation = null,
        array|null $data = null,
        string|null $user = null
    ): Response {

        // authorize request
        $tenantId = $this->tenantIdentity->identifier();
        $userId = $this->userIdentity->identifier();

        try {

            if ($operation !== null) {
                $result = $this->processOperation($tenantId, $userId, $operation, $data ?? [], $version, $transaction);

                if ($result instanceof Response) {
                    return $result;
                }

                return new JsonResponse([
                    'version' => $version,
                    'transaction' => $transaction,
                    'operation' => $operation,
                    'status' => 'success',
                    'data' => $result
                ], JsonResponse::HTTP_OK);
            }

            throw new InvalidArgumentException('Operation must be provided');

        } catch (Throwable $t) {
            $this->logger->error('Error processing request', ['exception' => $t]);
            return new JsonResponse([
                'version' => $version,
                'transaction' => $transaction,
                'operation' => $operation,
                'status' => 'error',
                'data' => [
                    'code' => $t->getCode(),
                    'message' => $t->getMessage()
                ]
            ], JsonResponse::HTTP_INTERNAL_SERVER_ERROR);
        }
    }

    /**
     * Process a single operation
     */
    private function processOperation(string $tenantId, string $userId, string $operation, array $data, int $version = 1, string $transaction = ''): mixed {
        return match ($operation) {
            // Provider operations
            'provider.list' => $this->providerList($tenantId, $userId, $data),
            'provider.fetch' => $this->providerFetch($tenantId, $userId, $data),
            'provider.extant' => $this->providerExtant($tenantId, $userId, $data),

            // Service operations
            'service.list' => $this->serviceList($tenantId, $userId, $data),
            'service.fetch' => $this->serviceFetch($tenantId, $userId, $data),
            'service.extant' => $this->serviceExtant($tenantId, $userId, $data),
            'service.create' => $this->serviceCreate($tenantId, $userId, $data),
            'service.update' => $this->serviceUpdate($tenantId, $userId, $data),
            'service.delete' => $this->serviceDelete($tenantId, $userId, $data),
            'service.test' => $this->serviceTest($tenantId, $userId, $data),

            // Collection operations
            'collection.list' => $this->collectionList($tenantId, $userId, $data),
            'collection.fetch' => $this->collectionFetch($tenantId, $userId, $data),
            'collection.extant' => $this->collectionExtant($tenantId, $userId, $data),
            'collection.create' => $this->collectionCreate($tenantId, $userId, $data),
            'collection.update' => $this->collectionUpdate($tenantId, $userId, $data),
            'collection.delete' => $this->collectionDelete($tenantId, $userId, $data),
            'collection.copy' => $this->collectionCopy($tenantId, $userId, $data),
            'collection.move' => $this->collectionMove($tenantId, $userId, $data),

            // Entity operations
            'entity.listBulk' => $this->entityListBulk($tenantId, $userId, $data),
            'entity.listStream' => $this->entityListStream($tenantId, $userId, $data, $version, $transaction),
            'entity.fetch' => $this->entityFetch($tenantId, $userId, $data),
            'entity.extant' => $this->entityExtant($tenantId, $userId, $data),
            'entity.delta' => $this->entityDelta($tenantId, $userId, $data),
            'entity.create' => $this->entityCreate($tenantId, $userId, $data),
            'entity.update' => $this->entityUpdate($tenantId, $userId, $data),
            'entity.delete' => $this->entityDelete($tenantId, $userId, $data),
            'entity.copy' => $this->entityCopy($tenantId, $userId, $data),
            'entity.move' => $this->entityMove($tenantId, $userId, $data),
            'entity.read' => $this->entityRead($tenantId, $userId, $data),
            'entity.read.chunk' => $this->entityReadChunk($tenantId, $userId, $data),
            'entity.write' => $this->entityWrite($tenantId, $userId, $data),
            'entity.write.chunk' => $this->entityWriteChunk($tenantId, $userId, $data),

            default => throw new InvalidArgumentException(self::ERR_INVALID_OPERATION . $operation)
        };
    }

    // ==================== Identifier Helpers ====================

    /**
     * Parse a required collection target identifier (provider:service:collection)
     */
    private function collectionTarget(array $data, string $key = 'target'): CollectionIdentifier {
        if (!isset($data[$key])) {
            throw new InvalidArgumentException('Missing parameter: ' . $key);
        }
        if (!is_string($data[$key])) {
            throw new InvalidArgumentException("Invalid parameter: $key must be a string");
        }
        $identifier = ResourceIdentifier::fromString($data[$key]);
        if (!$identifier instanceof CollectionIdentifier) {
            throw new InvalidArgumentException(self::ERR_TARGET_COLLECTION);
        }
        return $identifier;
    }

    /**
     * Parse an optional collection target identifier (absent = root)
     */
    private function collectionTargetOptional(array $data, string $key = 'target'): ?CollectionIdentifier {
        if (!isset($data[$key]) || $data[$key] === null || $data[$key] === '') {
            return null;
        }
        return $this->collectionTarget($data, $key);
    }

    /**
     * Parse a required entity target identifier (provider:service:collection:entity)
     */
    private function entityTarget(array $data, string $key = 'target'): EntityIdentifier {
        if (!isset($data[$key])) {
            throw new InvalidArgumentException('Missing parameter: ' . $key);
        }
        if (!is_string($data[$key])) {
            throw new InvalidArgumentException("Invalid parameter: $key must be a string");
        }
        $identifier = ResourceIdentifier::fromString($data[$key]);
        if (!$identifier instanceof EntityIdentifier) {
            throw new InvalidArgumentException(self::ERR_TARGET_ENTITY);
        }
        return $identifier;
    }

    // ==================== Provider Operations ====================

    private function providerList(string $tenantId, string $userId, array $data): mixed {

        if (isset($data['targets'])) {
            if (!is_array($data['targets'])) {
                throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
            }

            foreach ($data['targets'] as $target) {
                if (!is_string($target)) {
                    throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
                }
            }
        }

        return $this->manager->providerList($tenantId, $userId, $data['targets'] ?? []);

    }

    private function providerFetch(string $tenantId, string $userId, array $data): mixed {

        if (!isset($data['target'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGET);
        }
        if (!is_string($data['target'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGET);
        }

        return $this->manager->providerFetch($tenantId, $userId, $data['target']);

    }

    private function providerExtant(string $tenantId, string $userId, array $data): mixed {

        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }

        foreach ($data['targets'] as $target) {
            if (!is_string($target)) {
                throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
            }
        }

        return $this->manager->providerExtant($tenantId, $userId, $data['targets']);

    }

    // ==================== Service Operations =====================

    private function serviceList(string $tenantId, string $userId, array $data): mixed {

        $targets = null;
        if (isset($data['targets']) && is_array($data['targets'])) {
            $targets = ResourceIdentifiers::fromArray($data['targets']);
            foreach ($targets as $target) {
                if (!$target instanceof CollectionIdentifier && !$target instanceof ServiceIdentifier) {
                    throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service, provider:service:collection, or provider:service:collection:entity identifiers');
                }
            }
        }

        return $this->manager->serviceList($tenantId, $userId, $targets);

    }

    private function serviceFetch(string $tenantId, string $userId, array $data): mixed {

        if (!isset($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_PROVIDER);
        }
        if (!is_string($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_PROVIDER);
        }
        if (!isset($data['identifier'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_IDENTIFIER);
        }
        if (!is_string($data['identifier'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_IDENTIFIER);
        }

        return $this->manager->serviceFetch($tenantId, $userId, $data['provider'], $data['identifier']);
    }

    private function serviceExtant(string $tenantId, string $userId, array $data): mixed {

        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }
        $targets = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($targets as $target) {
            if (!$target instanceof ServiceIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service identifiers');
            }
        }

        return $this->manager->serviceExtant($tenantId, $userId, $targets);
    }

    private function serviceCreate(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_PROVIDER);
        }
        if (!is_string($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_PROVIDER);
        }
        if (!isset($data['data'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }
        if (!is_array($data['data'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_DATA);
        }

        return $this->manager->serviceCreate(
            $tenantId,
            $userId,
            $data['provider'],
            $data['data']
        );
    }

    private function serviceUpdate(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_PROVIDER);
        }
        if (!is_string($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_PROVIDER);
        }
        if (!isset($data['identifier'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_IDENTIFIER);
        }
        if (!is_string($data['identifier'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_IDENTIFIER);
        }
        if (!isset($data['data'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }
        if (!is_array($data['data'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_DATA);
        }
        if (isset($data['delta']) && !is_bool($data['delta'])) {
            throw new InvalidArgumentException('Invalid parameter: delta must be a boolean');
        }

        return $this->manager->serviceUpdate(
            $tenantId,
            $userId,
            $data['provider'],
            $data['identifier'],
            $data['data'],
            $data['delta'] ?? false,
        );
    }

    private function serviceDelete(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_PROVIDER);
        }
        if (!is_string($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_PROVIDER);
        }
        if (!isset($data['identifier'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_IDENTIFIER);
        }
        if (!is_string($data['identifier'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_IDENTIFIER);
        }

        return $this->manager->serviceDelete(
            $tenantId,
            $userId,
            $data['provider'],
            $data['identifier']
        );
    }

    private function serviceTest(string $tenantId, string $userId, array $data): mixed {

        if (!isset($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_PROVIDER);
        }
        if (!is_string($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_PROVIDER);
        }

        if (!isset($data['identifier']) && !isset($data['location']) && !isset($data['identity'])) {
            throw new InvalidArgumentException('Either a service identifier or location and identity must be provided for service test');
        }

        return $this->manager->serviceTest(
            $tenantId,
            $userId,
            $data['provider'],
            $data['identifier'] ?? null,
            $data['location'] ?? null,
            $data['identity'] ?? null,
        );
    }

    // ==================== Collection Operations ====================

    private function collectionList(string $tenantId, string $userId, array $data): mixed {
        $sources = null;
        if (isset($data['sources']) && is_array($data['sources'])) {
            $sources = ResourceIdentifiers::fromArray($data['sources']);
            foreach ($sources as $source) {
                if (!$source instanceof CollectionIdentifier && !$source instanceof ServiceIdentifier) {
                    throw new InvalidArgumentException('Invalid parameter: sources must contain provider:service or provider:service:collection identifiers');
                }
            }
        }

        $filter = $data['filter'] ?? null;
        $sort = $data['sort'] ?? null;

        return $this->manager->collectionList($tenantId, $userId, $sources, $filter, $sort);
    }

    private function collectionFetch(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }

        $targetIdentifiers = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($targetIdentifiers as $targetIdentifier) {
            if (!$targetIdentifier instanceof CollectionIdentifier) {
                throw new InvalidArgumentException(self::ERR_TARGET_COLLECTION);
            }
        }

        $list = $this->manager->collectionFetch(
            $tenantId,
            $userId,
            $targetIdentifier
        );
        return $list;
    }

    private function collectionExtant(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }

        $sources = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($sources as $source) {
            if (!$source instanceof CollectionIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service:collection identifiers');
            }
        }

        return $this->manager->collectionExtant($tenantId, $userId, $sources);
    }

    private function collectionCreate(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_PROVIDER);
        }
        if (!is_string($data['provider'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_PROVIDER);
        }
        if (!isset($data['service'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_SERVICE);
        }
        if (!is_string($data['service'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_SERVICE);
        }
        if (!isset($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }
        if (!is_array($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_DATA);
        }

        $targetIdentifier = $this->collectionTargetOptional($data);

        return $this->manager->collectionCreate(
            $tenantId,
            $userId,
            $data['provider'],
            $data['service'],
            $targetIdentifier,
            $data['properties'],
            $data['options'] ?? []
        );
    }

    private function collectionUpdate(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }
        if (!is_array($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_DATA);
        }

        $targetIdentifier = $this->collectionTarget($data);

        return $this->manager->collectionUpdate(
            $tenantId,
            $userId,
            $targetIdentifier,
            $data['properties']
        );
    }

    private function collectionDelete(string $tenantId, string $userId, array $data): mixed {
        $targetIdentifier = $this->collectionTarget($data);

        $result = $this->manager->collectionDelete($tenantId, $userId, $targetIdentifier, $data['options'] ?? []);

        if (is_bool($result)) {
            return [
                'disposition' => 'deleted'
            ];
        }

        if ($result instanceof JsonSerializable) {
            return [
                'disposition' => 'moved',
                'mutation' => $result
            ];
        }

        return $result;
    }

    private function collectionCopy(string $tenantId, string $userId, array $data): mixed {
        $sourceIdentifier = $this->collectionTarget($data, 'source');
        $targetIdentifier = $this->collectionTargetOptional($data);

        return $this->manager->collectionCopy($tenantId, $userId, $targetIdentifier, $sourceIdentifier);
    }

    private function collectionMove(string $tenantId, string $userId, array $data): mixed {
        $sourceIdentifier = $this->collectionTarget($data, 'source');
        $targetIdentifier = $this->collectionTargetOptional($data);

        return $this->manager->collectionMove($tenantId, $userId, $targetIdentifier, $sourceIdentifier);
    }

    // ==================== Entity Operations ====================

    private function entityListBulk(string $tenantId, string $userId, array $data): mixed {

        if (isset($data['sources'])) {
            if (!is_array($data['sources'])) {
                throw new InvalidArgumentException(self::ERR_INVALID_SOURCES);
            }

            $sources = ResourceIdentifiers::fromArray($data['sources']);
            foreach ($sources as $source) {
                if (!$source instanceof ServiceIdentifier && !$source instanceof CollectionIdentifier) {
                    throw new InvalidArgumentException('Invalid parameter: sources must contain provider:service or provider:service:collection identifiers');
                }
            }
        } else {
            $sources = null;
        }

        $filter = $data['filter'] ?? null;
        $sort = $data['sort'] ?? null;
        $range = $data['range'] ?? null;

        return $this->manager->entityListBulk($tenantId, $userId, $sources, $filter, $sort, $range);

    }

    private function entityListStream(string $tenantId, string $userId, array $data, int $version, string $transaction): StreamedNdJsonResponse {

        if (isset($data['sources'])) {
            if (!is_array($data['sources'])) {
                throw new InvalidArgumentException(self::ERR_INVALID_SOURCES);
            }

            $sources = ResourceIdentifiers::fromArray($data['sources']);
            foreach ($sources as $source) {
                if (!$source instanceof ServiceIdentifier && !$source instanceof CollectionIdentifier) {
                    throw new InvalidArgumentException('Invalid parameter: sources must contain provider:service or provider:service:collection identifiers');
                }
            }
        } else {
            $sources = null;
        }

        $filter = $data['filter'] ?? null;
        $sort   = $data['sort'] ?? null;
        $range  = $data['range'] ?? null;

        $entities = $this->manager->entityListStream($tenantId, $userId, $sources, $filter, $sort, $range);

        return new StreamedNdJsonResponse(
            $this->streamEnvelope($entities, $version, $transaction),
            1,
            200,
            ['Content-Type' => 'application/json'],
        );
    }

    /**
     * Wrap a generator of JsonSerializable domain objects in the canonical NDJSON
     * stream envelope shared by every streaming operation:
     *
     *   control:start {version, transaction, total?}  — total? = expected count
     *   data {data}                                    — one per domain object
     *   error {message}                                — on failure, then stop
     *   control:end {total}                            — total = objects emitted
     *
     * If the generator leads with an {@see ExpectedTotal} event, its value is
     * folded into the start frame's `total` (the progress denominator) rather
     * than emitted as a data frame.
     *
     * @param \Generator<\JsonSerializable> $items
     */
    private function streamEnvelope(\Generator $items, int $version, string $transaction): \Generator {
        // Peek the first event: an expected-total marker rides on the start frame.
        $expected = null;
        $items->rewind();
        if ($items->valid() && $items->current() instanceof ExpectedTotal) {
            $expected = $items->current()->expectedTotal();
            $items->next();
        }

        $start = ['type' => 'control', 'status' => 'start', 'version' => $version, 'transaction' => $transaction];
        if ($expected !== null) {
            $start['total'] = $expected;
        }
        yield $start;

        $total = 0;
        try {
            for (; $items->valid(); $items->next()) {
                $item = $items->current();
                if (!$item instanceof \JsonSerializable) {
                    continue;
                }
                yield ['type' => 'data', 'data' => $item->jsonSerialize()];
                $total++;
            }
        } catch (\Throwable $t) {
            $this->logger->error('Error streaming response', ['exception' => $t]);
            yield ['type' => 'error', 'message' => $t->getMessage()];
            return;
        }

        yield ['type' => 'control', 'status' => 'end', 'total' => $total];
    }

    private function entityFetch(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }

        $targets = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($targets as $target) {
            if (!$target instanceof EntityIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service:collection:entity identifiers');
            }
        }

        return $this->manager->entityFetchBulk(
            $tenantId,
            $userId,
            ...$targets->all()
        );
    }

    private function entityExtant(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }

        $targets = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($targets as $target) {
            if (!$target instanceof CollectionIdentifier && !$target instanceof EntityIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service:collection or provider:service:collection:entity identifiers');
            }
        }

        return $this->manager->entityExtant($tenantId, $userId, $targets);
    }

    private function entityDelta(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }

        $targets = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($targets as $target) {
            if (!$target instanceof CollectionIdentifier && !$target instanceof EntityIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service:collection or provider:service:collection:signature identifiers');
            }
        }

        return $this->manager->entityDelta($tenantId, $userId, $targets);
    }

    private function entityCreate(string $tenantId, string $userId, array $data = []): mixed {
        if (!isset($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }
        if (!is_array($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_DATA);
        }

        $target = $this->collectionTarget($data);
        $options = $data['options'] ?? [];

        return $this->manager->entityCreate($tenantId, $userId, $target, $data['properties'], $options);
    }

    private function entityUpdate(string $tenantId, string $userId, array $data = []): mixed {
        if (!isset($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }
        if (!is_array($data['properties'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_DATA);
        }

        $target = $this->entityTarget($data);

        return $this->manager->entityModify($tenantId, $userId, $target, $data['properties']);
    }

    private function entityDelete(string $tenantId, string $userId, array $data): mixed {
        if (!isset($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_TARGETS);
        }
        if (!is_array($data['targets'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_TARGETS);
        }

        $targets = ResourceIdentifiers::fromArray($data['targets']);
        foreach ($targets as $target) {
            if (!$target instanceof EntityIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: targets must contain provider:service:collection:entity identifiers');
            }
        }

        return $this->manager->entityDelete($tenantId, $userId, ...$targets->all());
    }

    private function entityMove(string $tenantId, string $userId, array $data): mixed {
        return $this->entityRelocate($tenantId, $userId, $data, 'entityMove');
    }

    private function entityCopy(string $tenantId, string $userId, array $data): mixed {
        return $this->entityRelocate($tenantId, $userId, $data, 'entityCopy');
    }

    /**
     * Shared request handling for entity move/copy operations
     */
    private function entityRelocate(string $tenantId, string $userId, array $data, string $method): mixed {
        if (!isset($data['sources'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_SOURCES);
        }
        if (!is_array($data['sources'])) {
            throw new InvalidArgumentException(self::ERR_INVALID_SOURCES);
        }

        $target = $this->collectionTarget($data);

        $sources = ResourceIdentifiers::fromArray($data['sources']);
        foreach ($sources as $source) {
            if (!$source instanceof EntityIdentifier) {
                throw new InvalidArgumentException('Invalid parameter: sources must contain provider:service:collection:entity identifiers');
            }
        }

        return $this->manager->{$method}($tenantId, $userId, $target, ...$sources->all());
    }

    // ==================== Entity Content Operations ====================

    private function entityRead(string $tenantId, string $userId, array $data = []): mixed {
        $target = $this->entityTarget($data);

        $content = $this->manager->entityRead($tenantId, $userId, $target);

        return [
            'content' => $content !== null ? base64_encode($content) : null,
            'encoding' => 'base64'
        ];
    }

    private function entityReadChunk(string $tenantId, string $userId, array $data = []): mixed {
        if (!isset($data['offset']) || !is_int($data['offset'])) {
            throw new InvalidArgumentException('Missing parameter: offset');
        }
        if (!isset($data['length']) || !is_int($data['length'])) {
            throw new InvalidArgumentException('Missing parameter: length');
        }

        $target = $this->entityTarget($data);

        $chunk = $this->manager->entityReadChunk(
            $tenantId,
            $userId,
            $target,
            $data['offset'],
            $data['length']
        );

        return [
            'content' => $chunk !== null ? base64_encode($chunk) : null,
            'encoding' => 'base64',
            'offset' => $data['offset'],
            'length' => $chunk !== null ? strlen($chunk) : 0,
        ];
    }

    private function entityWrite(string $tenantId, string $userId, array $data = []): mixed {
        if (!isset($data['content'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }

        $target = $this->entityTarget($data);

        // Decode content if base64 encoded
        $content = $data['content'];
        if (isset($data['encoding']) && $data['encoding'] === 'base64') {
            $content = base64_decode($content);
            if ($content === false) {
                throw new InvalidArgumentException('Invalid base64 encoded content');
            }
        }

        $bytesWritten = $this->manager->entityWrite($tenantId, $userId, $target, $content);

        return [
            'bytesWritten' => $bytesWritten
        ];
    }

    private function entityWriteChunk(string $tenantId, string $userId, array $data = []): mixed {
        if (!isset($data['offset']) || !is_int($data['offset'])) {
            throw new InvalidArgumentException('Missing parameter: offset');
        }
        if (!isset($data['content'])) {
            throw new InvalidArgumentException(self::ERR_MISSING_DATA);
        }

        $target = $this->entityTarget($data);

        // Decode content if base64 encoded
        $content = $data['content'];
        if (isset($data['encoding']) && $data['encoding'] === 'base64') {
            $content = base64_decode($content);
            if ($content === false) {
                throw new InvalidArgumentException('Invalid base64 encoded content');
            }
        }

        $bytesWritten = $this->manager->entityWriteChunk(
            $tenantId,
            $userId,
            $target,
            $data['offset'],
            $content
        );

        return [
            'bytesWritten' => $bytesWritten,
            'offset' => $data['offset'],
        ];
    }

}