<?php
/**
 * @link https://craftcms.com/
 * @copyright Copyright (c) Pixel & Tonic, Inc.
 * @license https://craftcms.github.io/license/
 */

namespace craft\services;

use Craft;
use craft\base\ElementContainerFieldInterface;
use craft\base\ElementInterface as BaseElementInterface;
use craft\base\FieldInterface;
use craft\base\GqlInlineFragmentFieldInterface;
use craft\behaviors\FieldLayoutBehavior;
use craft\db\Query as DbQuery;
use craft\db\Table;
use craft\enums\CmsEdition;
use craft\errors\GqlException;
use craft\events\ConfigEvent;
use craft\events\DefineGqlValidationRulesEvent;
use craft\events\ExecuteGqlQueryEvent;
use craft\events\RegisterGqlDirectivesEvent;
use craft\events\RegisterGqlMutationsEvent;
use craft\events\RegisterGqlQueriesEvent;
use craft\events\RegisterGqlSchemaComponentsEvent;
use craft\events\RegisterGqlTypesEvent;
use craft\gql\ArgumentManager;
use craft\gql\base\Directive;
use craft\gql\base\GeneratorInterface;
use craft\gql\base\SingularTypeInterface;
use craft\gql\directives\FormatDateTime;
use craft\gql\directives\Markdown;
use craft\gql\directives\Money;
use craft\gql\directives\ParseRefs;
use craft\gql\directives\StripTags;
use craft\gql\directives\Transform;
use craft\gql\directives\Trim;
use craft\gql\ElementQueryConditionBuilder;
use craft\gql\GqlEntityRegistry;
use craft\gql\interfaces\Element as ElementInterface;
use craft\gql\interfaces\elements\Address as AddressInterface;
use craft\gql\interfaces\elements\Asset as AssetInterface;
use craft\gql\interfaces\elements\Category as CategoryInterface;
use craft\gql\interfaces\elements\Entry as EntryInterface;
use craft\gql\interfaces\elements\GlobalSet as GlobalSetInterface;
use craft\gql\interfaces\elements\Tag as TagInterface;
use craft\gql\interfaces\elements\User as UserInterface;
use craft\gql\mutations\Asset as AssetMutation;
use craft\gql\mutations\Category as CategoryMutation;
use craft\gql\mutations\Entry as EntryMutation;
use craft\gql\mutations\GlobalSet as GlobalSetMutation;
use craft\gql\mutations\Ping as PingMutation;
use craft\gql\mutations\Tag as TagMutation;
use craft\gql\queries\Address as AddressQuery;
use craft\gql\queries\Asset as AssetQuery;
use craft\gql\queries\Category as CategoryQuery;
use craft\gql\queries\Entry as EntryQuery;
use craft\gql\queries\GlobalSet as GlobalSetQuery;
use craft\gql\queries\Ping as PingQuery;
use craft\gql\queries\Tag as TagQuery;
use craft\gql\queries\User as UserQuery;
use craft\gql\TypeLoader;
use craft\gql\TypeManager;
use craft\gql\types\DateTime;
use craft\gql\types\Mutation;
use craft\gql\types\Number;
use craft\gql\types\Query;
use craft\gql\types\QueryArgument;
use craft\helpers\DateTimeHelper;
use craft\helpers\Db;
use craft\helpers\Gql as GqlHelper;
use craft\helpers\ProjectConfig as ProjectConfigHelper;
use craft\helpers\StringHelper;
use craft\models\FieldLayout;
use craft\models\GqlSchema;
use craft\models\GqlToken;
use craft\models\Section;
use craft\records\GqlSchema as GqlSchemaRecord;
use craft\records\GqlToken as GqlTokenRecord;
use GraphQL\Error\DebugFlag;
use GraphQL\Error\Error;
use GraphQL\GraphQL;
use GraphQL\Type\Definition\Directive as GqlDirective;
use GraphQL\Type\Schema;
use GraphQL\Validator\DocumentValidator;
use GraphQL\Validator\Rules\DisableIntrospection;
use GraphQL\Validator\Rules\FieldsOnCorrectType;
use GraphQL\Validator\Rules\KnownTypeNames;
use GraphQL\Validator\Rules\QueryComplexity;
use GraphQL\Validator\Rules\QueryDepth;
use Throwable;
use yii\base\Component;
use yii\base\Exception;
use yii\base\InvalidArgumentException;
use yii\base\UnknownMethodException;
use yii\caching\TagDependency;

/**
 * GraphQL service.
 *
 * An instance of the service is available via [[\craft\base\ApplicationTrait::getGql()|`Craft::$app->getGql()`]].
 *
 * @author Pixel & Tonic, Inc. <support@pixelandtonic.com>
 * @since 3.3.0
 */
class Gql extends Component
{
    /**
     * @event RegisterGqlTypesEvent The event that is triggered when registering GraphQL types.
     *
     * Plugins get a chance to add their own GraphQL types.
     * See [GraphQL API](https://craftcms.com/docs/5.x/extend/graphql.html) for documentation on adding GraphQL support.
     *
     * ---
     * ```php
     * use craft\events\RegisterGqlTypesEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     *
     * Event::on(Gql::class, Gql::EVENT_REGISTER_GQL_TYPES, function(RegisterGqlTypesEvent $event) {
     *     // Add my GraphQL types
     *     $event->types[] = MyType::class;
     * });
     * ```
     */
    public const EVENT_REGISTER_GQL_TYPES = 'registerGqlTypes';

    /**
     * @event RegisterGqlQueriesEvent The event that is triggered when registering GraphQL queries.
     *
     * Plugins get a chance to add their own GraphQL queries.
     * See [GraphQL API](https://craftcms.com/docs/5.x/extend/graphql.html) for documentation on adding GraphQL support.
     *
     * ---
     * ```php
     * use craft\events\RegisterGqlQueriesEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     * use GraphQL\Type\Definition\Type;
     *
     * Event::on(Gql::class, Gql::EVENT_REGISTER_GQL_QUERIES, function(RegisterGqlQueriesEvent $event) {
     *     // Add my GraphQL queries
     *     $event->queries['queryPluginData'] =
     *     [
     *         'type' => Type::listOf(MyType::getType()),
     *         'args' => MyArguments::getArguments(),
     *         'resolve' => MyResolver::class . '::resolve'
     *     ];
     * });
     * ```
     */
    public const EVENT_REGISTER_GQL_QUERIES = 'registerGqlQueries';

    /**
     * @event RegisterGqlMutationsEvent The event that is triggered when registering GraphQL mutations.
     *
     * Plugins get a chance to add their own GraphQL mutations.
     * See [GraphQL API](https://craftcms.com/docs/5.x/extend/graphql.html) for documentation on adding GraphQL support.
     *
     * ---
     * ```php
     * use craft\events\RegisterGqlMutationsEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     * use GraphQL\Type\Definition\Type;
     *
     * Event::on(Gql::class, Gql::EVENT_REGISTER_GQL_MUTATIONS, function(RegisterGqlMutationsEvent $event) {
     *     // Add my GraphQL mutations
     *     $event->mutations['mutationPluginData'] =
     *     [
     *         'type' => Type::listOf(MyType::getType()),
     *         'args' => MyArguments::getArguments(),
     *     ];
     * });
     * ```
     */
    public const EVENT_REGISTER_GQL_MUTATIONS = 'registerGqlMutations';

    /**
     * @event RegisterGqlDirectivesEvent The event that is triggered when registering GraphQL directives.
     *
     * Plugins get a chance to add their own GraphQL directives.
     * See [GraphQL API](https://craftcms.com/docs/5.x/extend/graphql.html) for documentation on adding GraphQL support.
     *
     * ---
     * ```php
     * use craft\events\RegisterGqlDirectivesEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     *
     * Event::on(Gql::class,
     *     Gql::EVENT_REGISTER_GQL_DIRECTIVES,
     *     function(RegisterGqlDirectivesEvent $event) {
     *         $event->directives[] = MyDirective::class;
     *     }
     * );
     * ```
     */
    public const EVENT_REGISTER_GQL_DIRECTIVES = 'registerGqlDirectives';

    /**
     * @event RegisterGqlSchemaComponentsEvent The event that is triggered when registering GraphQL schema components.
     * @since 3.5.0
     */
    public const EVENT_REGISTER_GQL_SCHEMA_COMPONENTS = 'registerGqlSchemaComponents';

    /**
     * @event DefineGqlValidationRulesEvent The event that is triggered when defining validation rules to be used.
     *
     * Plugins get a chance to alter the GraphQL validation rule list.
     *
     * ---
     * ```php
     * use craft\events\DefineGqlValidationRulesEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     * use GraphQL\Type\Definition\Type;
     * use GraphQL\Validator\Rules\DisableIntrospection;
     *
     * Event::on(Gql::class, Gql::::EVENT_DEFINE_GQL_VALIDATION_RULES, function (DefineGqlValidationRulesEvent $event) {
     *     // Disable introspection permanently.
     *     $event->validationRules[DisableIntrospection::class] = new DisableIntrospection();
     * });
     * ```
     */
    public const EVENT_DEFINE_GQL_VALIDATION_RULES = 'defineGqlValidationRules';

    /**
     * @event ExecuteGqlQueryEvent The event that is triggered before executing the GraphQL query.
     *
     * Plugins get a chance to modify the query or return a cached response.
     *
     * ---
     * ```php
     * use craft\events\ExecuteGqlQueryEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     *
     * Event::on(Gql::class,
     *     Gql::EVENT_BEFORE_EXECUTE_GQL_QUERY,
     *     function(ExecuteGqlQueryEvent $event) {
     *         // Set the result from cache
     *         $event->result = ...;
     *     }
     * );
     * ```
     *
     * @since 3.3.11
     */
    public const EVENT_BEFORE_EXECUTE_GQL_QUERY = 'beforeExecuteGqlQuery';

    /**
     * @event ExecuteGqlQueryEvent The event that is triggered after executing the GraphQL query.
     *
     * Plugins get a chance to do something after a performed GraphQL query.
     *
     * ---
     * ```php
     * use craft\events\ExecuteGqlQueryEvent;
     * use craft\services\Gql;
     * use yii\base\Event;
     *
     * Event::on(Gql::class,
     *     Gql::EVENT_AFTER_EXECUTE_GQL_QUERY,
     *     function(ExecuteGqlQueryEvent $event) {
     *         // Cache the results from $event->result or just tweak them
     *     }
     * );
     * ```
     *
     * @since 3.3.11
     */
    public const EVENT_AFTER_EXECUTE_GQL_QUERY = 'afterExecuteGqlQuery';

    /**
     * @since 3.3.12
     */
    public const CACHE_TAG = 'graphql';

    /**
     * The field name to use when fetching count of related elements
     *
     * @since 3.4.0
     */
    public const GRAPHQL_COUNT_FIELD = '_count';

    /**
     * Complexity value for accessing a simple field.
     *
     * @since 3.6.0
     */
    public const GRAPHQL_COMPLEXITY_SIMPLE_FIELD = 1;

    /**
     * Complexity value for accessing a field that will trigger a single query for the request.
     *
     * @since 3.6.0
     */
    public const GRAPHQL_COMPLEXITY_QUERY = 10;

    /**
     * Complexity value for accessing a field that will add an instance of eager-loading for the request.
     *
     * @since 3.6.0
     */
    public const GRAPHQL_COMPLEXITY_EAGER_LOAD = 25;

    /**
     * Complexity value for accessing a field that will likely trigger a CPU heavy operation.
     *
     * @since 3.6.0
     */
    public const GRAPHQL_COMPLEXITY_CPU_HEAVY = 200;

    /**
     * Complexity value for accessing a field that will trigger a query for every parent returned.
     *
     * @since 3.6.0
     */
    public const GRAPHQL_COMPLEXITY_NPLUS1 = 500;

    /**
     * @var Schema|null Currently loaded schema definition
     */
    private ?Schema $_schemaDef = null;

    /**
     * @var GqlSchema|null The active GraphQL schema
     * @see setActiveSchema()
     */
    private ?GqlSchema $_schema = null;

    /**
     * @var array Content arguments by element class
     * @see getOrSetContentArguments()
     */
    private array $_contentArguments = [];

    /**
     * @var array Custom field arguments by field layout UUID
     * @see getFieldLayoutArguments()
     */
    private array $_fieldArguments = [];

    /**
     * @var TypeManager|null GQL type manager
     */
    private ?TypeManager $_typeManager = null;

    /**
     * @var array
     */
    private array $_typeDefinitions = [];

    /**
     * @var GqlToken|null
     * @see getPublicToken()
     */
    private ?GqlToken $_publicToken = null;

    /**
     * Returns the GraphQL schema.
     *
     * @param GqlSchema|null $schema
     * @param bool $prebuildSchema should the schema be deep-scanned and pre-built instead of lazy-loaded
     * @return Schema
     * @throws GqlException in case of invalid schema
     */
    public function getSchemaDef(?GqlSchema $schema = null, bool $prebuildSchema = false): Schema
    {
        if ($schema) {
            $this->setActiveSchema($schema);
        }
        if (!$this->_schemaDef || $prebuildSchema) {
            // Either cached version was not found or we need a pre-built schema.
            $registeredTypes = $this->_registerGqlTypes();
            $this->_registerGqlQueries();
            $this->_registerGqlMutations();

            $schemaConfig = [
                'typeLoader' => TypeLoader::class . '::loadType',
                'query' => TypeLoader::loadType('Query'),
                'mutation' => TypeLoader::loadType('Mutation'),
                'directives' => $this->_loadGqlDirectives(),
            ];

            // If we're not required to pre-build the schema the relevant GraphQL types will be added to the Schema
            // as the query is being resolved thanks to the magic of lazy-loading, so we needn't worry.
            if (!$prebuildSchema) {
                $this->_schemaDef = new Schema($schemaConfig);
                return $this->_schemaDef;
            }

            foreach ($registeredTypes as $registeredType) {
                if (method_exists($registeredType, 'getTypeGenerator')) {
                    $typeGeneratorClass = $registeredType::getTypeGenerator();
                    if (is_subclass_of($typeGeneratorClass, GeneratorInterface::class)) {
                        foreach ($typeGeneratorClass::generateTypes() as $type) {
                            $schemaConfig['types'][] = $type;
                        }
                    }
                }
            }

            try {
                $this->_schemaDef = new Schema($schemaConfig);
                $this->_schemaDef->getTypeMap();
            } catch (Throwable $exception) {
                throw new GqlException('Failed to validate the GQL Schema - ' . $exception->getMessage(), previous: $exception);
            }
        }

        return $this->_schemaDef;
    }

    /**
     * Return a set of validation rules to use.
     *
     * @param bool $debug Whether debugging validation rules should be allowed.
     * @param bool $isIntrospectionQuery Whether this is an introspection query
     * @return array
     */
    public function getValidationRules(bool $debug = false, bool $isIntrospectionQuery = false): array
    {
        $validationRules = DocumentValidator::defaultRules();

        if (!$debug) {
            // Remove the rules which would generate a full schema just for a nice message, to avoid performance hit.
            unset(
                $validationRules[KnownTypeNames::class],
                $validationRules[FieldsOnCorrectType::class]
            );
        }

        $generalConfig = Craft::$app->getConfig()->getGeneral();

        if (!$isIntrospectionQuery) {
            // Set complexity rule, if defined,
            if (!empty($generalConfig->maxGraphqlComplexity)) {
                $validationRules[QueryComplexity::class] = new QueryComplexity($generalConfig->maxGraphqlComplexity);
            }

            // Set depth rule, if defined,
            if (!empty($generalConfig->maxGraphqlDepth)) {
                $validationRules[QueryDepth::class] = new QueryDepth($generalConfig->maxGraphqlDepth);
            }
        }

        if (!$generalConfig->enableGraphqlIntrospection && Craft::$app->getUser()->getIsGuest()) {
            $validationRules[DisableIntrospection::class] = new DisableIntrospection();
        }

        // Fire a 'defineGqlValidationRules' event
        if ($this->hasEventHandlers(self::EVENT_DEFINE_GQL_VALIDATION_RULES)) {
            $event = new DefineGqlValidationRulesEvent([
                'validationRules' => $validationRules,
                'debug' => $debug,
            ]);
            $this->trigger(self::EVENT_DEFINE_GQL_VALIDATION_RULES, $event);
            $validationRules = $event->validationRules;
        }

        return array_values($validationRules);
    }

    /**
     * Execute a GraphQL query for a given schema.
     *
     * @param GqlSchema $schema The schema definition to use.
     * @param string $query The query string to execute.
     * @param array|null $variables The variables to use.
     * @param string|null $operationName The operation name.
     * @param bool $debugMode Whether debug mode validations rules should be used for GraphQL.
     * @return array
     * @since 3.3.11
     */
    public function executeQuery(
        GqlSchema $schema,
        string $query,
        ?array $variables = null,
        ?string $operationName = null,
        bool $debugMode = false,
    ): array {
        $context = [
            'conditionBuilder' => Craft::createObject([
                'class' => ElementQueryConditionBuilder::class,
            ]),
            'argumentManager' => Craft::createObject([
                'class' => ArgumentManager::class,
            ]),
        ];

        // Fire a 'beforeExecuteGqlQuery' event
        if ($this->hasEventHandlers(self::EVENT_BEFORE_EXECUTE_GQL_QUERY)) {
            $event = new ExecuteGqlQueryEvent([
                'schemaId' => $schema->id,
                'query' => $query,
                'variables' => $variables,
                'operationName' => $operationName,
                'context' => $context,
            ]);
            $this->trigger(self::EVENT_BEFORE_EXECUTE_GQL_QUERY, $event);
            $query = $event->query;
            $rootValue = $event->rootValue;
            $variables = $event->variables;
            $operationName = $event->operationName;
            $context = $event->context;
            $result = $event->result;
        } else {
            $result = $rootValue = null;
        }

        if ($result === null) {
            $cacheKey = $this->_getCacheKey(
                $schema,
                $query,
                $rootValue,
                $variables,
                $operationName,
            );

            if ($cacheKey && ($cachedResult = $this->getCachedResult($cacheKey)) !== null) {
                $result = $cachedResult;
            } else {
                $isIntrospectionQuery = GqlHelper::isIntrospectionQuery($query);
                $prebuildSchema = $isIntrospectionQuery || !Craft::$app->getConfig()->getGeneral()->lazyGqlTypes;
                $schemaDef = $this->getSchemaDef($schema, $prebuildSchema);
                $elementsService = Craft::$app->getElements();
                $elementsService->startCollectingCacheInfo();

                $result = GraphQL::executeQuery(
                    $schemaDef,
                    $query,
                    $rootValue,
                    $context,
                    $variables,
                    $operationName,
                    null,
                    $this->getValidationRules($debugMode, $isIntrospectionQuery)
                )
                    ->setErrorsHandler([$this, 'handleQueryErrors'])
                    ->toArray($debugMode ? DebugFlag::INCLUDE_DEBUG_MESSAGE | DebugFlag::INCLUDE_TRACE : false);

                [$dep, $duration] = $elementsService->stopCollectingCacheInfo();

                if (empty($result['errors']) && $cacheKey) {
                    $this->setCachedResult($cacheKey, $result, $dep, $duration);
                }
            }
        }

        // Fire an 'afterExecuteGqlQuery' event
        if ($this->hasEventHandlers(self::EVENT_AFTER_EXECUTE_GQL_QUERY)) {
            $event = new ExecuteGqlQueryEvent([
                'schemaId' => $schema->id,
                'query' => $query,
                'variables' => $variables,
                'operationName' => $operationName,
                'context' => $context,
                'rootValue' => $rootValue,
                'result' => $result,
            ]);
            $this->trigger(self::EVENT_AFTER_EXECUTE_GQL_QUERY, $event);
            $result = $event->result;
        }

        return $result ?? [];
    }

    /**
     * Invalidates all GraphQL result caches.
     *
     * @since 3.3.12
     */
    public function invalidateCaches(): void
    {
        TagDependency::invalidate(Craft::$app->getCache(), self::CACHE_TAG);
    }

    /**
     * Returns the cached result for a key.
     *
     * @param string $cacheKey
     * @return array|null
     * @since 3.3.12
     */
    public function getCachedResult(string $cacheKey): ?array
    {
        return Craft::$app->getCache()->get($cacheKey) ?: null;
    }

    /**
     * Cache a result for the key and tag it.
     *
     * @param string $cacheKey
     * @param array $result
     * @param TagDependency|null $dependency
     * @param int|null $duration
     * @since 3.3.12
     */
    public function setCachedResult(string $cacheKey, array $result, ?TagDependency $dependency = null, ?int $duration = null): void
    {
        if ($dependency === null) {
            $dependency = new TagDependency();
        }

        // Add the global graphql cache tag
        $dependency->tags[] = self::CACHE_TAG;

        Craft::$app->getCache()->set($cacheKey, $result, $duration, $dependency);
    }

    /**
     * Returns the active GraphQL schema.
     *
     * @return GqlSchema
     * @throws GqlException if no schema is currently active.
     */
    public function getActiveSchema(): GqlSchema
    {
        if (!$this->_schema) {
            throw new GqlException('No schema is active.');
        }

        return $this->_schema;
    }

    /**
     * Sets the active GraphQL schema.
     *
     * @param GqlSchema|null $schema The schema, or `null` to unset the active schema
     * @throws Exception
     */
    public function setActiveSchema(?GqlSchema $schema = null): void
    {
        $this->_schema = $schema;
    }

    /**
     * Returns all GraphQL tokens.
     *
     * @return GqlToken[]
     * @since 3.4.0
     */
    public function getTokens(): array
    {
        $rows = $this->_createTokenQuery()->all();
        $schemas = [];
        $names = [];

        foreach ($rows as $row) {
            $token = new GqlToken($row);

            if (!$token->getIsPublic()) {
                $schemas[] = $token;
                $names[] = $token->name;
            }
        }

        // Sort them by name
        array_multisort($names, SORT_ASC, SORT_STRING, $schemas);

        return $schemas;
    }

    /**
     * Returns the public schema. If it does not exist and admin changes are allowed, it will be created.
     *
     * @return GqlSchema|null
     * @throws Exception
     */
    public function getPublicSchema(): ?GqlSchema
    {
        return $this->getPublicToken()?->getSchema();
    }

    /**
     * Returns all of the known GraphQL schema components.
     *
     * @return array
     * @since 3.5.0
     */
    public function getAllSchemaComponents(): array
    {
        $queries = [];
        $mutations = [];

        // Sites
        $label = Craft::t('app', 'Sites');
        [$queries[$label], $mutations[$label]] = $this->siteSchemaComponents();

        // Elements
        $label = Craft::t('app', 'All elements');
        [$queries[$label], $mutations[$label]] = $this->elementSchemaComponents();

        // Entries
        $label = Craft::t('app', 'Entries');
        [$queries[$label], $mutations[$label]] = $this->entrySchemaComponents();

        // Assets
        $label = Craft::t('app', 'Assets');
        [$queries[$label], $mutations[$label]] = $this->assetSchemaComponents();

        // Global Sets
        $label = Craft::t('app', 'Global Sets');
        [$queries[$label], $mutations[$label]] = $this->globalSetSchemaComponents();

        // Users
        $label = Craft::t('app', 'Users');
        [$queries[$label], $mutations[$label]] = $this->userSchemaComponents();

        // Categories
        $label = Craft::t('app', 'Categories');
        [$queries[$label], $mutations[$label]] = $this->categorySchemaComponents();

        // Tags
        $label = Craft::t('app', 'Tags');
        [$queries[$label], $mutations[$label]] = $this->tagSchemaComponents();

        // Fire a 'registerGqlSchemaComponents' event
        if ($this->hasEventHandlers(self::EVENT_REGISTER_GQL_SCHEMA_COMPONENTS)) {
            $event = new RegisterGqlSchemaComponentsEvent([
                'queries' => $queries,
                'mutations' => $mutations,
            ]);
            $this->trigger(self::EVENT_REGISTER_GQL_SCHEMA_COMPONENTS, $event);
            $queries = $event->queries;
            $mutations = $event->mutations;
        }

        return [
            'queries' => $queries,
            'mutations' => $mutations,
        ];
    }

    /**
     * Flush all GraphQL caches, registries and loaders.
     */
    public function flushCaches(): void
    {
        $this->_schema = null;
        $this->_schemaDef = null;
        $this->_contentArguments = [];
        $this->_typeDefinitions = [];
        TypeLoader::flush();
        GqlEntityRegistry::flush();
        $this->invalidateCaches();
    }

    /**
     * Returns a GraphQL token by its ID.
     *
     * @param int $id
     * @return GqlToken|null
     * @since 3.4.0
     */
    public function getTokenById(int $id): ?GqlToken
    {
        $result = $this->_createTokenQuery()
            ->where(['id' => $id])
            ->one();

        return $result ? new GqlToken($result) : null;
    }

    /**
     * Returns a GraphQL token by its name.
     *
     * @param string $tokenName
     * @return GqlToken|null
     * @since 3.4.0
     */
    public function getTokenByName(string $tokenName): ?GqlToken
    {
        $result = $this->_createTokenQuery()
            ->where(['name' => $tokenName])
            ->one();

        return $result ? new GqlToken($result) : null;
    }

    /**
     * Returns a GraphQL token by its UID.
     *
     * @param string $uid
     * @return GqlToken
     * @throws InvalidArgumentException if $uid is invalid
     * @since 3.4.0
     */
    public function getTokenByUid(string $uid): GqlToken
    {
        $result = $this->_createTokenQuery()
            ->where(['uid' => $uid])
            ->one();

        if (!$result) {
            throw new InvalidArgumentException('Invalid UID');
        }

        return new GqlToken($result);
    }

    /**
     * Returns a GraphQL token by its access token.
     *
     * @param string $token
     * @return GqlToken
     * @throws InvalidArgumentException if $token is invalid
     * @since 3.4.0
     */
    public function getTokenByAccessToken(string $token): GqlToken
    {
        if ($token === GqlToken::PUBLIC_TOKEN) {
            $publicToken = $this->getPublicToken();

            if (!$publicToken) {
                throw new InvalidArgumentException('Invalid access token');
            }

            return $publicToken;
        }

        $result = $this->_createTokenQuery()
            ->where(['accessToken' => $token])
            ->one();

        if (!$result) {
            throw new InvalidArgumentException('Invalid access token');
        }

        return new GqlToken($result);
    }

    /**
     * Returns the public token. If it does not exist and admin changes are allowed, it will be created.
     *
     * @return GqlToken|null
     * @since 3.5.0
     */
    public function getPublicToken(): ?GqlToken
    {
        if (!isset($this->_publicToken)) {
            $config = Craft::$app->getProjectConfig()->get(ProjectConfig::PATH_GRAPHQL_PUBLIC_TOKEN) ?? [];
            $this->_publicToken = $this->_createPublicToken($config);

            if ($this->_publicToken) {
                $this->_publicToken->id = $this->_createTokenQuery()
                    ->select(['id'])
                    ->where(['accessToken' => GqlToken::PUBLIC_TOKEN])
                    ->scalar();
            }
        }

        return $this->_publicToken;
    }

    /**
     * Creates a public token with the given config.
     *
     * @param array $config
     * @return GqlToken|null
     */
    private function _createPublicToken(array $config): ?GqlToken
    {
        $schema = $this->_getPublicSchema();

        if (!$schema) {
            if (!Craft::$app->getConfig()->getGeneral()->allowAdminChanges) {
                return null;
            }

            $schema = $this->_createPublicSchema();
        }

        return new GqlToken([
            'name' => 'Public Token',
            'accessToken' => GqlToken::PUBLIC_TOKEN,
            'schema' => $schema,
            'enabled' => $config['enabled'] ?? false,
            'expiryDate' => DateTimeHelper::toDateTime($config['expiryDate'] ?? false) ?: null,
        ]);
    }

    /**
     * Saves a GraphQL token.
     *
     * @param GqlToken $token the schema to save
     * @param bool $runValidation Whether the schema should be validated
     * @return bool Whether the schema was saved successfully
     * @throws Exception
     * @since 3.4.0
     */
    public function saveToken(GqlToken $token, bool $runValidation = true): bool
    {
        if ($token->isTemporary) {
            return false;
        }

        if ($runValidation && !$token->validate()) {
            Craft::info('Token not saved due to validation error.', __METHOD__);
            return false;
        }

        // Public token information is stored in the project config
        if ($token->accessToken === GqlToken::PUBLIC_TOKEN) {
            $data = [
                'enabled' => $token->enabled,
                'expiryDate' => $token->expiryDate?->getTimestamp(),
            ];

            $projectConfigService = Craft::$app->getProjectConfig();
            $muteEvents = $projectConfigService->muteEvents;
            $projectConfigService->muteEvents = false;
            Craft::$app->getProjectConfig()->set(ProjectConfig::PATH_GRAPHQL_PUBLIC_TOKEN, $data);
            $projectConfigService->muteEvents = $muteEvents;
        }

        $this->_saveTokenInternal($token);

        return true;
    }

    /**
     * Handle public token settings being updated.
     *
     * @param ConfigEvent $event
     * @since 3.5.0
     */
    public function handleChangedPublicToken(ConfigEvent $event): void
    {
        // If we're just adding a public schema, ensure it makes it in.
        ProjectConfigHelper::ensureAllGqlSchemasProcessed();

        $this->_publicToken = $this->_createPublicToken($event->newValue);
    }

    /**
     * Deletes a GraphQL token by its ID.
     *
     * @param int $id The schemas's ID
     * @return bool Whether the schema was deleted.
     * @since 3.4.0
     */
    public function deleteTokenById(int $id): bool
    {
        $record = GqlTokenRecord::findOne($id);

        if (!$record) {
            return true;
        }

        return $record->delete();
    }

    /**
     * Saves a GraphQL schema.
     *
     * @param GqlSchema $schema the schema to save
     * @param bool $runValidation Whether the schema should be validated
     * @return bool Whether the schema was saved successfully
     * @throws Exception
     * @since 3.4.0
     */
    public function saveSchema(GqlSchema $schema, bool $runValidation = true): bool
    {
        $isNewSchema = !$schema->id;

        if ($runValidation && !$schema->validate()) {
            Craft::info('Schema not saved due to validation error.', __METHOD__);
            return false;
        }

        if ($isNewSchema && empty($schema->uid)) {
            $schema->uid = StringHelper::UUID();
        } elseif (empty($schema->uid)) {
            $schema->uid = Db::uidById(Table::GQLSCHEMAS, $schema->id);
        }

        $configPath = ProjectConfig::PATH_GRAPHQL_SCHEMAS . '.' . $schema->uid;
        $configData = $schema->getConfig();
        Craft::$app->getProjectConfig()->set($configPath, $configData, "Save GraphQL schema “{$schema->name}”");

        if ($isNewSchema) {
            $schema->id = Db::idByUid(Table::GQLSCHEMAS, $schema->uid);
        }

        return true;
    }

    /**
     * Handle schema change
     *
     * @param ConfigEvent $event
     * @since 3.4.0
     */
    public function handleChangedSchema(ConfigEvent $event): void
    {
        $schemaUid = $event->tokenMatches[0];
        $data = $event->newValue;

        $transaction = Craft::$app->getDb()->beginTransaction();

        try {
            $schemaRecord = $this->_getSchemaRecord($schemaUid);
            $isNew = $schemaRecord->getIsNewRecord();

            $schemaRecord->uid = $schemaUid;
            $schemaRecord->name = $data['name'];
            $schemaRecord->isPublic = (bool)($data['isPublic'] ?? false);
            $schemaRecord->scope = ($data['scope'] ?? false) ?: [];

            // Save the schema record
            $schemaRecord->save(false);

            // If we're updating to 3.4+, check if the old token info for this schema was cached
            if (
                $isNew &&
                ($allSchemas = Craft::$app->getCache()->get('migration:add_gql_project_config_support:schemas')) &&
                !empty($allSchemas[$schemaUid])
            ) {
                $migratedSchema = $allSchemas[$schemaUid];
                $token = new GqlToken([
                    'name' => $migratedSchema['name'],
                    'accessToken' => $migratedSchema['accessToken'],
                    'enabled' => $migratedSchema['enabled'],
                    'expiryDate' => $migratedSchema['expiryDate'],
                    'lastUsed' => $migratedSchema['lastUsed'],
                    'schemaId' => $schemaRecord->id,
                ]);
                $this->saveToken($token);
            }

            $transaction->commit();
        } catch (Throwable $e) {
            $transaction->rollBack();
            throw $e;
        }

        $this->invalidateCaches();
    }

    /**
     * Deletes a GraphQL schema by its ID.
     *
     * @param int $id The schema's ID
     * @return bool Whether the schema was deleted.
     * @since 3.4.0
     */
    public function deleteSchemaById(int $id): bool
    {
        $schema = $this->getSchemaById($id);

        if (!$schema) {
            return false;
        }

        return $this->deleteSchema($schema);
    }

    /**
     * Deletes a GraphQL schema.
     *
     * @param GqlSchema $schema
     * @return bool
     * @since 3.4.0
     */
    public function deleteSchema(GqlSchema $schema): bool
    {
        Craft::$app->getProjectConfig()->remove(ProjectConfig::PATH_GRAPHQL_SCHEMAS . '.' . $schema->uid, "Delete the “{$schema->name}” GraphQL schema");
        return true;
    }


    /**
     * Handle schema getting deleted
     *
     * @param ConfigEvent $event
     * @since 3.4.0
     */
    public function handleDeletedSchema(ConfigEvent $event): void
    {
        $uid = $event->tokenMatches[0];
        $schemaRecord = $this->_getSchemaRecord($uid);

        if ($schemaRecord->getIsNewRecord()) {
            return;
        }

        $db = Craft::$app->getDb();
        $transaction = $db->beginTransaction();

        try {
            // Delete the schema
            Db::delete(Table::GQLSCHEMAS, [
                'id' => $schemaRecord->id,
            ]);

            $transaction->commit();
        } catch (Throwable $e) {
            $transaction->rollBack();
            throw $e;
        }

        $this->invalidateCaches();
    }

    /**
     * Get a schema by its ID.
     *
     * @param int $id The schema's ID
     * @return GqlSchema|null
     */
    public function getSchemaById(int $id): ?GqlSchema
    {
        $result = $this->_createSchemaQuery()
            ->where(['id' => $id])
            ->one();

        return $result ? new GqlSchema($result) : null;
    }

    /**
     * Get a schema by its UID.
     *
     * @param string $uid The schema's UID
     * @return GqlSchema|null
     * @since 3.4.0
     */
    public function getSchemaByUid(string $uid): ?GqlSchema
    {
        $result = $this->_createSchemaQuery()
            ->where(['uid' => $uid])
            ->one();

        return $result ? new GqlSchema($result) : null;
    }

    /**
     * Get all schemas.
     *
     * @return GqlSchema[]
     * @since 3.4.0
     */
    public function getSchemas(): array
    {
        $rows = $this->_createSchemaQuery()
            ->all();

        $schemas = [];

        foreach ($rows as $row) {
            $schemas[] = new GqlSchema($row);
        }

        return $schemas;
    }

    /**
     * Returns the content arguments
     *
     * @param class-string<BaseElementInterface> $elementType
     * @param callable $setter
     * @phpstan-param callable():array $setter
     * @return array
     * @since 5.0.0
     */
    public function getOrSetContentArguments(string $elementType, callable $setter): array
    {
        if (!isset($this->_contentArguments[$elementType])) {
            $this->_contentArguments[$elementType] = $setter();
        }
        return $this->_contentArguments[$elementType];
    }

    /**
     * Returns arguments for fields in the given field layout.
     *
     * @param FieldLayout $fieldLayout
     * @return array
     * @since 5.6.0
     */
    public function getFieldLayoutArguments(FieldLayout $fieldLayout): array
    {
        if (!isset($fieldLayout->type)) {
            throw new InvalidArgumentException('Field layout is missing its element type.');
        }

        if (!isset($this->_fieldArguments[$fieldLayout->uid])) {
            $this->_fieldArguments[$fieldLayout->uid] = $this->defineContentArgumentsForFields(
                $fieldLayout->type,
                $fieldLayout->getCustomFields(),
            );
        }

        return $this->_fieldArguments[$fieldLayout->uid];
    }

    /**
     * Returns the content arguments for a given element type and field layouts.
     *
     * @param class-string<BaseElementInterface> $elementType
     * @param FieldLayout[] $fieldLayouts
     * @return array
     * @since 5.0.0
     */
    public function defineContentArgumentsForFieldLayouts(string $elementType, array $fieldLayouts): array
    {
        $fields = [];
        $handledFieldLayouts = [];

        foreach ($fieldLayouts as $fieldLayout) {
            // avoid checking the same field layout more than once
            if (isset($fieldLayout->uid)) {
                if (isset($handledFieldLayouts[$fieldLayout->uid])) {
                    continue;
                }
                $handledFieldLayouts[$fieldLayout->uid] = true;
            }

            array_push($fields, ...$fieldLayout->getCustomFields());
        }

        return $this->defineContentArgumentsForFields($elementType, $fields);
    }

    /**
     * Returns the content arguments for a given element type and custom fields.
     *
     * @param class-string<BaseElementInterface> $elementType
     * @param FieldInterface[] $fields
     * @return array
     * @since 5.0.0
     */
    public function defineContentArgumentsForFields(string $elementType, array $fields): array
    {
        $arguments = [];
        $elementQuery = Craft::$app->getElements()->createElementQuery($elementType);

        foreach ($fields as $field) {
            if (
                !isset($arguments[$field->handle]) &&
                !$field instanceof GqlInlineFragmentFieldInterface &&
                !method_exists($elementQuery, $field->handle)
            ) {
                $arguments[$field->handle] = $field->getContentGqlQueryArgumentType();
            }
        }

        return $arguments;
    }

    /**
     * Returns the content arguments for an element class based on the given contexts.
     *
     * @param array $contexts
     * @param class-string<BaseElementInterface> $elementType
     * @return array
     */
    public function getContentArguments(array $contexts, string $elementType): array
    {
        /** @var FieldLayoutBehavior[] $contexts */
        return $this->getOrSetContentArguments($elementType, function() use ($contexts, $elementType): array {
            $fields = [];
            foreach ($contexts as $context) {
                if (GqlHelper::isSchemaAwareOf($elementType::gqlScopesByContext($context))) {
                    try {
                        array_push($fields, ...$context->getCustomFields());
                    } catch (UnknownMethodException) {
                    }
                }
            }
            return $this->defineContentArgumentsForFields($elementType, $fields);
        });
    }

    /**
     * Custom error handler for GraphQL query errors
     *
     * @param Error[] $errors
     * @param callable $formatter
     * @return Error[]
     * @since 3.6.2
     */
    public function handleQueryErrors(array $errors, callable $formatter): array
    {
        $devMode = Craft::$app->getConfig()->getGeneral()->devMode;

        foreach ($errors as &$error) {
            $originException = $nextException = $error;

            // Get the origin exception.
            while ($nextException = $nextException->getPrevious()) {
                $originException = $nextException;
            }

            // If devMode enabled, substitute the original exception here.
            if ($devMode && !empty($originException->getMessage())) {
                $error = $originException;
            } elseif (!$originException instanceof Error) {
                // If devMode not enabled and the error seems to be originating from Craft, display a generic message
                $error = new Error(
                    Craft::t('app', 'Something went wrong when processing the GraphQL query.')
                );
            }

            // Log it.
            Craft::$app->getErrorHandler()->logException($originException);
        }

        return array_map($formatter, $errors);
    }

    /**
     * Prepare field definitions for a given GraphQL type by giving plugins a chance to modify them.
     *
     * @param array $fields
     * @param string $typeName
     * @return array
     */
    public function prepareFieldDefinitions(array $fields, string $typeName): array
    {
        if (!array_key_exists($typeName, $this->_typeDefinitions)) {
            if ($this->_typeManager === null) {
                $this->_typeManager = Craft::createObject(TypeManager::class);
            }

            $this->_typeDefinitions[$typeName] = $this->_typeManager->registerFieldDefinitions($fields, $typeName);
        }

        return $this->_typeDefinitions[$typeName];
    }

    /**
     * Generate a cache key for the GraphQL operation. Returns null if caching is disabled or unable to generate one.
     *
     * @param GqlSchema $schema
     * @param string $query
     * @param mixed $rootValue
     * @param array|null $variables
     * @param string|null $operationName
     * @return string|null
     */
    private function _getCacheKey(
        GqlSchema $schema,
        string $query,
        mixed $rootValue,
        ?array $variables = null,
        ?string $operationName = null,
    ): ?string {
        // No cache key, if explicitly disabled
        $generalConfig = Craft::$app->getConfig()->getGeneral();

        if (!$generalConfig->enableGraphqlCaching) {
            return null;
        }

        // Do not cache mutations
        if (preg_match('/^\s*mutation(?P<operationName>\s+\w+)?\s*(?P<variables>\(.*\))?\s*{/si', $query)) {
            return null;
        }

        // No cache key if we have placeholder elements
        if (!empty(Craft::$app->getElements()->getPlaceholderElements())) {
            return null;
        }

        try {
            $cacheKey = self::CACHE_TAG .
                '::' . Craft::$app->getSites()->getCurrentSite()->id .
                '::' . $schema->uid .
                '::' . md5($query) .
                '::' . serialize($rootValue) .
                '::' . Craft::$app->getInfo()->configVersion .
                '::' . serialize($variables) .
                ($operationName ? "::$operationName" : '');
        } catch (Throwable $e) {
            Craft::$app->getErrorHandler()->logException($e);
            $cacheKey = null;
        }

        return $cacheKey;
    }

    /**
     * Register GraphQL types
     *
     * @return array the list of registered types.
     */
    private function _registerGqlTypes(): array
    {
        $types = [
            // Scalars
            DateTime::class,
            Number::class,
            QueryArgument::class,

            // Interfaces
            AddressInterface::class,
            ElementInterface::class,
            EntryInterface::class,
            AssetInterface::class,
            UserInterface::class,
            GlobalSetInterface::class,
            CategoryInterface::class,
            TagInterface::class,
        ];

        // Fire a 'registerGqlTypes' event
        if ($this->hasEventHandlers(self::EVENT_REGISTER_GQL_TYPES)) {
            $event = new RegisterGqlTypesEvent(['types' => $types]);
            $this->trigger(self::EVENT_REGISTER_GQL_TYPES, $event);
            $types = $event->types;
        }

        foreach ($types as $type) {
            /** @var class-string<SingularTypeInterface> $type */
            TypeLoader::registerType($type::getName(), "$type::getType");
        }

        return $types;
    }

    /**
     * Get GraphQL query definitions
     */
    private function _registerGqlQueries(): void
    {
        $queryList = [
            // Queries
            AddressQuery::getQueries(),
            PingQuery::getQueries(),
            EntryQuery::getQueries(),
            AssetQuery::getQueries(),
            UserQuery::getQueries(),
            GlobalSetQuery::getQueries(),
            CategoryQuery::getQueries(),
            TagQuery::getQueries(),
        ];

        // Flatten them
        $queries = array_merge(...$queryList);

        // Fire a 'registerGqlQueries' event
        if ($this->hasEventHandlers(self::EVENT_REGISTER_GQL_QUERIES)) {
            $event = new RegisterGqlQueriesEvent(['queries' => $queries]);
            $this->trigger(self::EVENT_REGISTER_GQL_QUERIES, $event);
            $queries = $event->queries;
        }

        TypeLoader::registerType('Query', fn() => call_user_func(Query::class . '::getType', $queries));
    }

    /**
     * Get GraphQL mutation definitions
     */
    private function _registerGqlMutations(): void
    {
        $mutationList = [
            // Mutations
            PingMutation::getMutations(),
            EntryMutation::getMutations(),
            TagMutation::getMutations(),
            CategoryMutation::getMutations(),
            GlobalSetMutation::getMutations(),
            AssetMutation::getMutations(),
        ];

        // Flatten them
        $mutations = array_merge(...$mutationList);

        // Fire a 'registerGqlMutations' event
        if ($this->hasEventHandlers(self::EVENT_REGISTER_GQL_MUTATIONS)) {
            $event = new RegisterGqlMutationsEvent(['mutations' => $mutations]);
            $this->trigger(self::EVENT_REGISTER_GQL_MUTATIONS, $event);
            $mutations = $event->mutations;
        }

        TypeLoader::registerType('Mutation', fn() => call_user_func(Mutation::class . '::getType', $mutations));
    }

    /**
     * Get GraphQL query definitions
     *
     * @return GqlDirective[]
     */
    private function _loadGqlDirectives(): array
    {
        /** @var class-string<Directive>[] $directiveClasses */
        $directiveClasses = [
            // Directives
            FormatDateTime::class,
            Markdown::class,
            Money::class,
            ParseRefs::class,
            StripTags::class,
            Trim::class,
        ];

        if (!Craft::$app->getConfig()->getGeneral()->disableGraphqlTransformDirective) {
            $directiveClasses[] = Transform::class;
        }

        // Fire a 'registerGqlDirectives' event
        if ($this->hasEventHandlers(self::EVENT_REGISTER_GQL_DIRECTIVES)) {
            $event = new RegisterGqlDirectivesEvent(['directives' => $directiveClasses]);
            $this->trigger(self::EVENT_REGISTER_GQL_DIRECTIVES, $event);
            $directiveClasses = $event->directives;
        }

        $directives = GraphQL::getStandardDirectives();

        foreach ($directiveClasses as $class) {
            /** @var class-string<Directive> $class */
            $directives[] = $class::create();
        }

        return $directives;
    }

    /**
     * Return site schema components.
     *
     * @return array
     */
    private function siteSchemaComponents(): array
    {
        $sites = Craft::$app->getSites()->getAllSites(true);
        $queryComponents = [];

        foreach ($sites as $site) {
            $queryComponents["sites.{$site->uid}:read"] = [
                'label' => Craft::t('app', 'Query for elements in the “{site}” site', [
                    'site' => $site->name,
                ]),
            ];
        }

        return [$queryComponents, []];
    }

    /**
     * Return element schema components.
     *
     * @return array
     */
    private function elementSchemaComponents(): array
    {
        $queryComponents = [
            'elements.drafts:read' => [
                'label' => Craft::t('app', 'Query for element drafts'),
            ],
            'elements.revisions:read' => [
                'label' => Craft::t('app', 'Query for element revisions'),
            ],
            'elements.inactive:read' => [
                'label' => Craft::t('app', 'Query for non-enabled elements'),
            ],
        ];

        return [$queryComponents, []];
    }

    /**
     * Return the available schema components for entries.
     *
     * @return array
     */
    private function entrySchemaComponents(): array
    {
        $queryComponents = [];
        $mutationComponents = [];

        $entriesService = Craft::$app->getEntries();
        $singles = $entriesService->getSectionsByType(Section::TYPE_SINGLE);

        foreach ($singles as $section) {
            $name = Craft::t('site', $section->name);
            $prefix = "sections.$section->uid";
            $queryComponents["$prefix:read"] = [
                'label' => Craft::t('app', 'Query for the “{name}” entry', ['name' => $name]),
            ];
            $mutationComponents["$prefix:save"] = [
                'label' => Craft::t('app', 'Save the “{section}” entry', ['section' => $name]),
            ];
        }

        foreach ($entriesService->getAllSections() as $section) {
            if ($section->type === Section::TYPE_SINGLE) {
                continue;
            }

            $name = Craft::t('site', $section->name);
            $prefix = "sections.$section->uid";

            $queryComponents["$prefix:read"] = [
                'label' => Craft::t('app', 'Query for entries in the “{name}” section', ['name' => $name]),
            ];

            $mutationComponents["$prefix:edit"] = [
                'label' => Craft::t('app', 'Edit entries in the “{name}” section', ['name' => $name]),
                'nested' => [
                    "$prefix:create" => [
                        'label' => Craft::t('app', 'Create entries in the “{section}” section', ['section' => $name]),
                    ],
                    "$prefix:save" => [
                        'label' => Craft::t('app', 'Save entries in the “{section}” section', ['section' => $name]),
                    ],
                    "$prefix:delete" => [
                        'label' => Craft::t('app', 'Delete entries in the “{section}” section', ['section' => $name]),
                    ],
                ],
            ];
        }

        // Add components for fields that manage nested entries
        $fieldsService = Craft::$app->getFields();
        /** @var ElementContainerFieldInterface[] $fields */
        $fields = array_merge(...array_map(
            fn(string $type) => $fieldsService->getFieldsByType($type),
            $fieldsService->getNestedEntryFieldTypes(),
        ));
        usort($fields, fn(ElementContainerFieldInterface $a, ElementContainerFieldInterface $b) =>
            $a::displayName() <=> $b::displayName());

        foreach ($fields as $field) {
            $name = Craft::t('site', $field->name);
            $type = $field::displayName();
            $prefix = "nestedentryfields.$field->uid";

            $queryComponents["$prefix:read"] = [
                'label' => Craft::t('app', 'Query for entries in the “{name}” {type} field', [
                    'name' => $name,
                    'type' => $type,
                ]),
            ];

            $mutationComponents["$prefix:edit"] = [
                'label' => Craft::t('app', 'Edit entries in the “{name}” {type} field', [
                    'name' => $name,
                    'type' => $type,
                ]),
                'nested' => [
                    "$prefix:create" => [
                        'label' => Craft::t('app', 'Create entries in the “{section}” {type} field', [
                            'section' => $name, // todo: change to 'name'
                            'type' => $type,
                        ]),
                    ],
                    "$prefix:save" => [
                        'label' => Craft::t('app', 'Save entries in the “{section}” {type} field', [
                            'section' => $name, // todo: change to 'name'
                            'type' => $type,
                        ]),
                    ],
                    "$prefix:delete" => [
                        'label' => Craft::t('app', 'Delete entries in the “{section}” {type} field', [
                            'section' => $name, // todo: change to 'name'
                            'type' => $type,
                        ]),
                    ],
                ],
            ];
        }

        return [$queryComponents, $mutationComponents];
    }

    /**
     * Return volume permissions.
     *
     * @return array
     */
    private function assetSchemaComponents(): array
    {
        $queryComponents = [];
        $mutationComponents = [];

        $volumes = Craft::$app->getVolumes()->getAllVolumes();

        if (!empty($volumes)) {
            foreach ($volumes as $volume) {
                $name = Craft::t('site', $volume->name);
                $prefix = "volumes.$volume->uid";
                $queryComponents["$prefix:read"] = [
                    'label' => Craft::t('app', 'Query for assets in the “{name}” volume', ['name' => $name]),
                ];
                $mutationComponents["$prefix:edit"] = [
                    'label' => Craft::t('app', 'Edit assets in the “{volume}” volume', ['volume' => $name]),
                    'nested' => [
                        "$prefix:create" => [
                            'label' => Craft::t('app', 'Create assets in the “{volume}” volume', ['volume' => $name]),
                        ],
                        "$prefix:save" => [
                            'label' => Craft::t('app', 'Modify assets in the “{volume}” volume', ['volume' => $name]),
                        ],
                        "$prefix:delete" => [
                            'label' => Craft::t('app', 'Delete assets from the “{volume}” volume', ['volume' => $name]),
                        ],
                    ],
                ];
            }
        }

        return [$queryComponents, $mutationComponents];
    }

    /**
     * Return global set permissions.
     *
     * @return array
     */
    private function globalSetSchemaComponents(): array
    {
        $queryComponents = [];
        $mutationComponents = [];

        $globalSets = Craft::$app->getGlobals()->getAllSets();

        if (!empty($globalSets)) {
            foreach ($globalSets as $globalSet) {
                $name = Craft::t('site', $globalSet->name);
                $prefix = "globalsets.$globalSet->uid";
                $queryComponents["$prefix:read"] = [
                    'label' => Craft::t('app', 'Query for the “{name}” global set', ['name' => $name]),
                ];
                $mutationComponents["$prefix:edit"] = [
                    'label' => Craft::t('app', 'Edit the “{globalSet}” global set.', ['globalSet' => $name]),
                ];
            }
        }

        return [$queryComponents, $mutationComponents];
    }

    /**
     * Return user permissions.
     *
     * @return array
     */
    private function userSchemaComponents(): array
    {
        if (Craft::$app->edition === CmsEdition::Solo) {
            return [[], []];
        }

        $queryComponents = [];
        $userGroups = Craft::$app->getUserGroups()->getAllGroups();

        $queryComponents['usergroups.everyone:read'] = [
            'label' => Craft::t('app', 'Query for users'),
        ];

        foreach ($userGroups as $userGroup) {
            $name = Craft::t('site', $userGroup->name);
            $prefix = "usergroups.$userGroup->uid";
            $queryComponents["$prefix:read"] = [
                'label' => Craft::t('app', 'Query for users in the “{name}” user group', ['name' => $name]),
            ];
        }

        return [$queryComponents, []];
    }

    /**
     * Return category group permissions.
     *
     * @return array
     */
    private function categorySchemaComponents(): array
    {
        $queryComponents = [];
        $mutationComponents = [];

        $categoryGroups = Craft::$app->getCategories()->getAllGroups();

        if (!empty($categoryGroups)) {
            foreach ($categoryGroups as $categoryGroup) {
                $name = Craft::t('site', $categoryGroup->name);
                $prefix = "categorygroups.$categoryGroup->uid";
                $queryComponents["$prefix:read"] = [
                    'label' => Craft::t('app', 'Query for categories in the “{name}” category group', ['name' => $name]),
                ];
                $mutationComponents["$prefix:edit"] = [
                    'label' => Craft::t('app', 'Edit categories in the “{categoryGroup}” category group', ['categoryGroup' => $name]),
                    'nested' => [
                        "$prefix:save" => [
                            'label' => Craft::t('app', 'Save categories in the “{categoryGroup}” category group', ['categoryGroup' => $name]),
                        ],
                        "$prefix:delete" => [
                            'label' => Craft::t('app', 'Delete categories from the “{categoryGroup}” category group', ['categoryGroup' => $name]),
                        ],
                    ],
                ];
            }
        }

        return [$queryComponents, $mutationComponents];
    }

    /**
     * Return tag group permissions.
     *
     * @return array
     */
    private function tagSchemaComponents(): array
    {
        $queryComponents = [];
        $mutationComponents = [];

        $tagGroups = Craft::$app->getTags()->getAllTagGroups();

        if (!empty($tagGroups)) {
            foreach ($tagGroups as $tagGroup) {
                $name = Craft::t('site', $tagGroup->name);
                $prefix = "taggroups.$tagGroup->uid";
                $queryComponents["$prefix:read"] = [
                    'label' => Craft::t('app', 'Query for tags in the “{name}” tag group', ['name' => $name]),
                ];
                $mutationComponents["$prefix:edit"] = [
                    'label' => Craft::t('app', 'Edit tags in the “{tagGroup}” tag group', ['tagGroup' => $name]),
                    'nested' => [
                        "$prefix:save" => [
                            'label' => Craft::t('app', 'Save tags in the “{tagGroup}” tag group', ['tagGroup' => $name]),
                        ],
                        "$prefix:delete" => [
                            'label' => Craft::t('app', 'Delete tags from the “{tagGroup}” tag group', ['tagGroup' => $name]),
                        ],
                    ],
                ];
            }
        }

        return [$queryComponents, $mutationComponents];
    }

    /**
     * Returns a DbCommand object prepped for retrieving tokens.
     *
     * @return DbQuery
     */
    private function _createTokenQuery(): DbQuery
    {
        return (new DbQuery())
            ->select([
                'id',
                'schemaId',
                'name',
                'accessToken',
                'enabled',
                'expiryDate',
                'lastUsed',
                'dateCreated',
                'uid',
            ])
            ->from([Table::GQLTOKENS]);
    }

    /**
     * Returns a DbCommand object prepped for retrieving schemas.
     *
     * @return DbQuery
     */
    private function _createSchemaQuery(): DbQuery
    {
        return (new DbQuery())
            ->select([
                'id',
                'name',
                'scope',
                'isPublic',
                'uid',
            ])
            ->from([Table::GQLSCHEMAS]);
    }

    /**
     * Get the public schema, if it exists.
     *
     * @return GqlSchema|null
     */
    private function _getPublicSchema(): ?GqlSchema
    {
        $result = $this->_createSchemaQuery()->where(['isPublic' => true])->one();

        return $result ? new GqlSchema($result) : null;
    }

    /**
     * Creates the public schema.
     *
     * @return GqlSchema
     */
    private function _createPublicSchema(): GqlSchema
    {
        $schemaUid = StringHelper::UUID();
        $publicSchema = new GqlSchema([
            'name' => 'Public Schema',
            'uid' => $schemaUid,
            'isPublic' => true,
        ]);

        $this->saveSchema($publicSchema, false);

        return $publicSchema;
    }

    /**
     * Gets a schema's record by uid.
     *
     * @param string $uid
     * @return GqlSchemaRecord
     */
    private function _getSchemaRecord(string $uid): GqlSchemaRecord
    {
        return GqlSchemaRecord::findOne(['uid' => $uid]) ?? new GqlSchemaRecord();
    }


    /**
     * Save a GQL Token record based on the model.
     *
     * @param GqlToken $token
     */
    private function _saveTokenInternal(GqlToken $token): void
    {
        $isNewToken = !$token->id;

        if ($isNewToken) {
            $tokenRecord = new GqlTokenRecord();
        } else {
            $tokenRecord = GqlTokenRecord::findOne($token->id) ?: new GqlTokenRecord();
        }

        $tokenRecord->name = $token->name;
        $tokenRecord->enabled = $token->enabled;
        $tokenRecord->expiryDate = Db::prepareDateForDb($token->expiryDate);
        $tokenRecord->lastUsed = Db::prepareDateForDb($token->lastUsed);
        $tokenRecord->schemaId = $token->schemaId;

        if ($token->accessToken) {
            $tokenRecord->accessToken = $token->accessToken;
        }

        $tokenRecord->save();
        $token->id = $tokenRecord->id;
        $token->uid = $tokenRecord->uid;
    }
}
