/// <reference path="./aggregate.d.ts" />
/// <reference path="./callback.d.ts" />
/// <reference path="./collection.d.ts" />
/// <reference path="./connection.d.ts" />
/// <reference path="./cursor.d.ts" />
/// <reference path="./document.d.ts" />
/// <reference path="./error.d.ts" />
/// <reference path="./expressions.d.ts" />
/// <reference path="./helpers.d.ts" />
/// <reference path="./middlewares.d.ts" />
/// <reference path="./indexes.d.ts" />
/// <reference path="./models.d.ts" />
/// <reference path="./mongooseoptions.d.ts" />
/// <reference path="./pipelinestage.d.ts" />
/// <reference path="./populate.d.ts" />
/// <reference path="./query.d.ts" />
/// <reference path="./schemaoptions.d.ts" />
/// <reference path="./schematypes.d.ts" />
/// <reference path="./session.d.ts" />
/// <reference path="./types.d.ts" />
/// <reference path="./utility.d.ts" />
/// <reference path="./validation.d.ts" />
/// <reference path="./inferrawdoctype.d.ts" />
/// <reference path="./inferschematype.d.ts" />
/// <reference path="./virtuals.d.ts" />
/// <reference path="./augmentations.d.ts" />

declare class NativeDate extends globalThis.Date { }

declare module 'mongoose' {
  import Kareem = require('kareem');
  import events = require('events');
  import mongodb = require('mongodb');
  import mongoose = require('mongoose');

  export type Mongoose = typeof mongoose;

  /**
   * Mongoose constructor. The exports object of the `mongoose` module is an instance of this
   * class. Most apps will only use this one instance.
   */
  export const Mongoose: new (options?: MongooseOptions | null) => Mongoose;

  export let Promise: any;

  /**
   * Can be extended to explicitly type specific models.
   */
  export interface Models {
    [modelName: string]: Model<any>
  }

  /** An array containing all models associated with this Mongoose instance. */
  export const models: Models;

  /**
   * Removes the model named `name` from the default connection, if it exists.
   * You can use this function to clean up any models you created in your tests to
   * prevent OverwriteModelErrors.
   */
  export function deleteModel(name: string | RegExp): Mongoose;

  /**
   * Sanitizes query filters against query selector injection attacks by wrapping
   * any nested objects that have a property whose name starts with `$` in a `$eq`.
   */
  export function sanitizeFilter<T>(filter: FilterQuery<T>): FilterQuery<T>;

  /** Gets mongoose options */
  export function get<K extends keyof MongooseOptions>(key: K): MongooseOptions[K];

  export function omitUndefined<T extends Record<string, any>>(val: T): T;

  /* ! ignore */
  export type CompileModelOptions = {
    overwriteModels?: boolean,
    connection?: Connection
  };

  export function model<TSchema extends Schema = any>(
    name: string,
    schema?: TSchema,
    collection?: string,
    options?: CompileModelOptions
  ): Model<
    InferSchemaType<TSchema>,
    ObtainSchemaGeneric<TSchema, 'TQueryHelpers'>,
    ObtainSchemaGeneric<TSchema, 'TInstanceMethods'>,
    ObtainSchemaGeneric<TSchema, 'TVirtuals'>,
    HydratedDocument<
      InferSchemaType<TSchema>,
      ObtainSchemaGeneric<TSchema, 'TVirtuals'> & ObtainSchemaGeneric<TSchema, 'TInstanceMethods'>,
      ObtainSchemaGeneric<TSchema, 'TQueryHelpers'>,
      ObtainSchemaGeneric<TSchema, 'TVirtuals'>,
      ObtainSchemaGeneric<TSchema, 'TSchemaOptions'>
    >,
    TSchema
  > & ObtainSchemaGeneric<TSchema, 'TStaticMethods'>;

  export function model<T>(name: string, schema?: Schema<T, any, any> | Schema<T & Document, any, any>, collection?: string, options?: CompileModelOptions): Model<T>;

  export function model<T, U, TQueryHelpers = {}>(
    name: string,
    schema?: Schema<T, any, any, TQueryHelpers, any, any, any>,
    collection?: string,
    options?: CompileModelOptions
  ): U;

  /** Returns an array of model names created on this instance of Mongoose. */
  export function modelNames(): Array<string>;

  /**
   * Overwrites the current driver used by this Mongoose instance. A driver is a
   * Mongoose-specific interface that defines functions like `find()`.
   */
  export function setDriver(driver: any): Mongoose;

  /** The node-mongodb-native driver Mongoose uses. */
  export { mongodb as mongo };

  /** Declares a global plugin executed on all Schemas. */
  export function plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): Mongoose;

  /** Getter/setter around function for pluralizing collection names. */
  export function pluralize(fn?: ((str: string) => string) | null): ((str: string) => string) | null;

  /** Sets mongoose options */
  export function set<K extends keyof MongooseOptions>(key: K, value: MongooseOptions[K]): Mongoose;
  export function set(options: { [K in keyof MongooseOptions]: MongooseOptions[K] }): Mongoose;

  /** The Mongoose version */
  export const version: string;

  export type AnyKeys<T> = { [P in keyof T]?: T[P] | any };
  export interface AnyObject {
    [k: string]: any
  }

  export type Require_id<T> = T extends { _id?: infer U }
    ? IfAny<U, T & { _id: Types.ObjectId }, T & Required<{ _id: U }>>
    : T & { _id: Types.ObjectId };

  export type Default__v<T, TSchemaOptions = {}> = TSchemaOptions extends { versionKey: false }
    ? T
    : TSchemaOptions extends { versionKey: infer VK }
      ? (
          // If VK is a *literal* string, add that property
          T & {
            [K in VK as K extends string
              ? (string extends K ? never : K) // drop if wide string
              : never
            ]: number
          }
        )
      : T extends { __v?: infer U }
        ? T
        : T & { __v: number };

  /** Helper type for getting the hydrated document type from the raw document type. The hydrated document type is what `new MyModel()` returns. */
  export type HydratedDocument<
    DocType,
    TOverrides = {},
    TQueryHelpers = {},
    TVirtuals = {},
    TSchemaOptions = {}
  > = IfAny<
    DocType,
    any,
    TOverrides extends Record<string, never> ?
      Document<unknown, TQueryHelpers, DocType, TVirtuals, TSchemaOptions> & Default__v<Require_id<DocType>, TSchemaOptions> :
      IfAny<
        TOverrides,
        Document<unknown, TQueryHelpers, DocType, TVirtuals, TSchemaOptions> & Default__v<Require_id<DocType>, TSchemaOptions>,
        Document<unknown, TQueryHelpers, DocType, TVirtuals, TSchemaOptions> & MergeType<
          Default__v<Require_id<DocType>, TSchemaOptions>,
          TOverrides
        >
      >
  >;
  export type HydratedSingleSubdocument<
    DocType,
    TOverrides = {}
  > = IfAny<
  DocType,
  any,
  TOverrides extends Record<string, never> ?
    Types.Subdocument<unknown, Record<string, never>, DocType> & Require_id<DocType> :
    IfAny<
      TOverrides,
      Types.Subdocument<unknown, Record<string, never>, DocType> & Require_id<DocType>,
      Types.Subdocument<unknown, Record<string, never>, DocType> & MergeType<
        Require_id<DocType>,
        TOverrides
      >
    >
  >;
  export type HydratedArraySubdocument<DocType, TOverrides = {}> = IfAny<
    DocType,
    any,
    TOverrides extends Record<string, never> ?
      Types.ArraySubdocument<unknown, Record<string, never>, DocType> & Require_id<DocType> :
      IfAny<
        TOverrides,
        Types.ArraySubdocument<unknown, Record<string, never>, DocType> & Require_id<DocType>,
        Types.ArraySubdocument<unknown, Record<string, never>, DocType> & MergeType<
          Require_id<DocType>,
          TOverrides
        >
      >
    >;

  export type HydratedDocumentFromSchema<TSchema extends Schema> = HydratedDocument<
    InferSchemaType<TSchema>,
    ObtainSchemaGeneric<TSchema, 'TInstanceMethods'> & ObtainSchemaGeneric<TSchema, 'TVirtuals'>,
    ObtainSchemaGeneric<TSchema, 'TQueryHelpers'>,
    ObtainSchemaGeneric<TSchema, 'TVirtuals'>,
    ObtainSchemaGeneric<TSchema, 'TSchemaOptions'>
  >;

  export interface TagSet {
    [k: string]: string;
  }

  export interface ToObjectOptions<RawDocType = unknown, THydratedDocumentType = HydratedDocument<RawDocType>> {
    /** if `options.virtuals = true`, you can set `options.aliases = false` to skip applying aliases. This option is a no-op if `options.virtuals = false`. */
    aliases?: boolean;
    /** if true, replace any conventionally populated paths with the original id in the output. Has no affect on virtual populated paths. */
    depopulate?: boolean;
    /** if true, convert Maps to POJOs. Useful if you want to `JSON.stringify()` the result of `toObject()`. */
    flattenMaps?: boolean;
    /** if true, convert any ObjectIds in the result to 24 character hex strings. */
    flattenObjectIds?: boolean;
    /** if true, convert any UUIDs in the result to 36 character hex strings. */
    flattenUUIDs?: boolean;
    /** apply all getters (path and virtual getters) */
    getters?: boolean;
    /** remove empty objects (defaults to true) */
    minimize?: boolean;
    /** If true, the resulting object will only have fields that are defined in the document's schema. By default, `toJSON()` & `toObject()` returns all fields in the underlying document from MongoDB, including ones that are not listed in the schema. */
    schemaFieldsOnly?: boolean;
    /** if set, mongoose will call this function to allow you to transform the returned object */
    transform?: boolean | ((
      doc: THydratedDocumentType,
      ret: Default__v<Require_id<RawDocType>>,
      options: ToObjectOptions<THydratedDocumentType>
    ) => any);
    /** If true, omits fields that are excluded in this document's projection. Unless you specified a projection, this will omit any field that has `select: false` in the schema. */
    useProjection?: boolean;
    /** if false, exclude the version key (`__v` by default) from the output */
    versionKey?: boolean;
    /** apply virtual getters (can override getters option) */
    virtuals?: boolean | string[];
  }

  export type DiscriminatorModel<M, T> = T extends Model<infer T, infer TQueryHelpers, infer TInstanceMethods, infer TVirtuals>
    ?
    M extends Model<infer M, infer MQueryHelpers, infer MInstanceMethods, infer MVirtuals>
      ? Model<Omit<M, keyof T> & T, MQueryHelpers | TQueryHelpers, MInstanceMethods | TInstanceMethods, MVirtuals | TVirtuals>
      : M
    : M;

  export type DiscriminatorSchema<DocType, M, TInstanceMethods, TQueryHelpers, TVirtuals, TStaticMethods, DisSchema> =
    DisSchema extends Schema<infer DisSchemaEDocType, infer DisSchemaM, infer DisSchemaInstanceMethods, infer DisSchemaQueryhelpers, infer DisSchemaVirtuals, infer DisSchemaStatics>
      ? Schema<MergeType<DocType, DisSchemaEDocType>, DiscriminatorModel<DisSchemaM, M>, DisSchemaInstanceMethods | TInstanceMethods, DisSchemaQueryhelpers | TQueryHelpers, DisSchemaVirtuals | TVirtuals, DisSchemaStatics & TStaticMethods>
      : Schema<DocType, M, TInstanceMethods, TQueryHelpers, TVirtuals, TStaticMethods>;

  type QueryResultType<T> = T extends Query<infer ResultType, any> ? ResultType : never;

  type PluginFunction<
    DocType,
    M,
    TInstanceMethods,
    TQueryHelpers,
    TVirtuals,
    TStaticMethods> = (schema: Schema<DocType, M, TInstanceMethods, TQueryHelpers, TVirtuals, TStaticMethods>, opts?: any) => void;

  export class Schema<
    RawDocType = any,
    TModelType = Model<RawDocType, any, any, any>,
    TInstanceMethods = {},
    TQueryHelpers = {},
    TVirtuals = {},
    TStaticMethods = {},
    TSchemaOptions = DefaultSchemaOptions,
    DocType extends ApplySchemaOptions<
      ObtainDocumentType<DocType, RawDocType, ResolveSchemaOptions<TSchemaOptions>>,
      ResolveSchemaOptions<TSchemaOptions>
    > = ApplySchemaOptions<
      ObtainDocumentType<any, RawDocType, ResolveSchemaOptions<TSchemaOptions>>,
      ResolveSchemaOptions<TSchemaOptions>
    >,
    THydratedDocumentType = HydratedDocument<FlatRecord<DocType>, TVirtuals & TInstanceMethods, {}, TVirtuals, ResolveSchemaOptions<TSchemaOptions>>
  >
    extends events.EventEmitter {
    /**
     * Create a new schema
     */
    constructor(
      definition?: SchemaDefinition<SchemaDefinitionType<RawDocType>, RawDocType, THydratedDocumentType> | DocType,
      options?: SchemaOptions<
        FlatRecord<DocType>,
        TInstanceMethods,
        TQueryHelpers,
        TStaticMethods,
        TVirtuals,
        THydratedDocumentType,
        IfEquals<
          TModelType,
          Model<any, any, any, any>,
          Model<DocType, TQueryHelpers, TInstanceMethods, TVirtuals, THydratedDocumentType>,
          TModelType
        >
      > | ResolveSchemaOptions<TSchemaOptions>
    );

    /** Adds key path / schema type pairs to this schema. */
    add(obj: SchemaDefinition<SchemaDefinitionType<RawDocType>, RawDocType> | Schema, prefix?: string): this;

    /**
     * Add an alias for `path`. This means getting or setting the `alias`
     * is equivalent to getting or setting the `path`.
     */
    alias(path: string, alias: string | string[]): this;

    /**
     * Array of child schemas (from document arrays and single nested subdocs)
     * and their corresponding compiled models. Each element of the array is
     * an object with 2 properties: `schema` and `model`.
     */
    childSchemas: { schema: Schema, model: any }[];

    /** Removes all indexes on this schema */
    clearIndexes(): this;

    /** Returns a copy of this schema */
    clone<T = this>(): T;

    discriminator<DisSchema = Schema>(name: string | number, schema: DisSchema, options?: DiscriminatorOptions): this;

    /** Returns a new schema that has the picked `paths` from this schema. */
    pick<T = this>(paths: string[], options?: SchemaOptions): T;

    /** Object containing discriminators defined on this schema */
    discriminators?: { [name: string]: Schema };

    /** Iterates the schemas paths similar to Array#forEach. */
    eachPath(fn: (path: string, type: SchemaType) => void): this;

    /** Defines an index (most likely compound) for this schema. */
    index(fields: IndexDefinition, options?: Omit<IndexOptions, 'unique'> & { unique?: boolean | [true, string] }): this;

    /**
     * Define a search index for this schema.
     *
     * @remarks Search indexes are only supported when used against a 7.0+ Mongo Atlas cluster.
     */
    searchIndex(description: SearchIndexDescription): this;

    /**
     * Returns a list of indexes that this schema declares, via `schema.index()`
     * or by `index: true` in a path's options.
     */
    indexes(): Array<[IndexDefinition, IndexOptions]>;

    /** Gets a schema option. */
    get<K extends keyof SchemaOptions>(key: K): SchemaOptions[K];

    /**
     * Loads an ES6 class into a schema. Maps [setters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set) + [getters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get), [static methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static),
     * and [instance methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Class_body_and_method_definitions)
     * to schema [virtuals](http://mongoosejs.com/docs/guide.html#virtuals),
     * [statics](http://mongoosejs.com/docs/guide.html#statics), and
     * [methods](http://mongoosejs.com/docs/guide.html#methods).
     */
    loadClass(model: Function, onlyVirtuals?: boolean): this;

    /** Adds an instance method to documents constructed from Models compiled from this schema. */
    method<Context = THydratedDocumentType>(name: string, fn: (this: Context, ...args: any[]) => any, opts?: any): this;
    method(obj: Partial<TInstanceMethods>): this;

    /** Object of currently defined methods on this schema. */
    methods: AddThisParameter<TInstanceMethods, THydratedDocumentType> & AnyObject;

    /** The original object passed to the schema constructor */
    obj: SchemaDefinition<SchemaDefinitionType<RawDocType>, RawDocType>;

    /** Returns a new schema that has the `paths` from the original schema, minus the omitted ones. */
    omit<T = this>(paths: string[], options?: SchemaOptions): T;

    options: SchemaOptions;

    /** Gets/sets schema paths. */
    path<ResultType extends SchemaType = SchemaType<any, THydratedDocumentType>>(path: string): ResultType;
    path<pathGeneric extends keyof RawDocType>(path: pathGeneric): SchemaType<RawDocType[pathGeneric]>;
    path(path: string, constructor: any): this;

    /** Lists all paths and their type in the schema. */
    paths: {
      [key: string]: SchemaType;
    };

    /** Returns the pathType of `path` for this schema. */
    pathType(path: string): string;

    /** Registers a plugin for this schema. */
    plugin<PFunc extends PluginFunction<DocType, TModelType, any, any, any, any>, POptions extends Parameters<PFunc>[1] = Parameters<PFunc>[1]>(fn: PFunc, opts?: POptions): this;

    /** Defines a post hook for the model. */

    // PostMiddlewareFunction
    // with errorHandler set to true
    post<T = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | RegExp, options: SchemaPostOptions & { errorHandler: true }, fn: ErrorHandlingMiddlewareWithOption<T>): this;
    post<T = THydratedDocumentType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { errorHandler: true }, fn: ErrorHandlingMiddlewareWithOption<T>): this;
    post<T extends Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions & { errorHandler: true }, fn: ErrorHandlingMiddlewareWithOption<T, Array<any>>): this;
    post<T = TModelType>(method: 'insertMany' | RegExp, options: SchemaPostOptions & { errorHandler: true }, fn: ErrorHandlingMiddlewareWithOption<T>): this;

    // this = never since it never happens
    post<T = never>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: false, query: false }, fn: PostMiddlewareFunction<never, never>): this;
    post<T = never>(method: MongooseDistinctQueryMiddleware|MongooseDistinctQueryMiddleware[], options: SchemaPostOptions & { document: boolean, query: false }, fn: PostMiddlewareFunction<T, QueryResultType<T>>): this;
    post<T = never>(method: MongooseDistinctDocumentMiddleware | MongooseDistinctDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: false, query: true }, fn: PostMiddlewareFunction<T, T>): this;
    // this = Document
    post<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], fn: PostMiddlewareFunction<T, T>): this;
    post<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], options: SchemaPostOptions & SchemaPostOptions, fn: PostMiddlewareFunction<T, T>): this;
    post<T = THydratedDocumentType>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: true, query: false }, fn: PostMiddlewareFunction<T, T>): this;
    post<T = THydratedDocumentType>(method: 'init', fn: PostMiddlewareFunction<T, T>): this;

    // this = Query
    post<T = Query<any, any>>(method: MongooseRawResultQueryMiddleware|MongooseRawResultQueryMiddleware[], fn: PostMiddlewareFunction<T, null | QueryResultType<T> | ModifyResult<QueryResultType<T>>>): this;
    post<T = Query<any, any>>(method: MongooseDefaultQueryMiddleware|MongooseDefaultQueryMiddleware[], fn: PostMiddlewareFunction<T, QueryResultType<T>>): this;
    post<T = Query<any, any>>(method: MongooseDistinctQueryMiddleware|MongooseDistinctQueryMiddleware[], options: SchemaPostOptions, fn: PostMiddlewareFunction<T, QueryResultType<T>>): this;
    post<T = Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: false, query: true }, fn: PostMiddlewareFunction<T, QueryResultType<T>>): this;
    // this = Union of Document and Query, could be called with any of them
    post<T = THydratedDocumentType|Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: true, query: true }, fn: PostMiddlewareFunction<T, T|QueryResultType<T>>): this;
    post<T = THydratedDocumentType|Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, fn: PostMiddlewareFunction<T, T|QueryResultType<T>>): this;

    // ErrorHandlingMiddlewareFunction
    // this = never since it never happens
    post<T = never>(method: MongooseDistinctQueryMiddleware|MongooseDistinctQueryMiddleware[], options: SchemaPostOptions & { document: boolean, query: false }, fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = never>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], options: SchemaPostOptions & { document: false, query: boolean }, fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = never>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: false, query: false }, fn: ErrorHandlingMiddlewareFunction<T>): this;
    // this = Document
    post<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = THydratedDocumentType>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: true, query: false }, fn: ErrorHandlingMiddlewareFunction<T>): this;
    // this = Query
    post<T = Query<any, any>>(method: MongooseDefaultQueryMiddleware|MongooseDefaultQueryMiddleware[], fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = Query<any, any>>(method: MongooseDistinctQueryMiddleware|MongooseDistinctQueryMiddleware[], options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: false, query: true }, fn: ErrorHandlingMiddlewareFunction<T>): this;
    // this = Union of Document and Query, could be called with any of them
    post<T = THydratedDocumentType|Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPostOptions & { document: true, query: true }, fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = THydratedDocumentType|Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;

    // method aggregate and insertMany with PostMiddlewareFunction
    post<T extends Aggregate<any>>(method: 'aggregate' | RegExp, fn: PostMiddlewareFunction<T, Array<AggregateExtract<T>>>): this;
    post<T extends Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T, Array<AggregateExtract<T>>>): this;
    post<T = TModelType>(method: 'insertMany' | RegExp, fn: PostMiddlewareFunction<T, T>): this;
    post<T = TModelType>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T, T>): this;

    // method aggregate and insertMany with ErrorHandlingMiddlewareFunction
    post<T extends Aggregate<any>>(method: 'aggregate' | RegExp, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
    post<T extends Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
    post<T = TModelType>(method: 'bulkWrite' | 'createCollection' | 'insertMany' | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
    post<T = TModelType>(method: 'bulkWrite' | 'createCollection' | 'insertMany' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;

    /** Defines a pre hook for the model. */
    // this = never since it never happens
    pre<T = never>(method: 'save', options: SchemaPreOptions & { document: false, query: boolean }, fn: PreSaveMiddlewareFunction<T>): this;
    pre<T = never>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPreOptions & { document: false, query: false }, fn: PreMiddlewareFunction<T>): this;
    pre<T = never>(method: MongooseDistinctQueryMiddleware|MongooseDistinctQueryMiddleware[], options: SchemaPreOptions & { document: boolean, query: false }, fn: PreMiddlewareFunction<T>): this;
    pre<T = never>(method: MongooseDistinctDocumentMiddleware | MongooseDistinctDocumentMiddleware[] | RegExp, options: SchemaPreOptions & { document: false, query: boolean }, fn: PreMiddlewareFunction<T>): this;
    // this = Union of Document and Query, could be called with any of them
    pre<T = THydratedDocumentType | Query<any, any>>(
      method: 'updateOne' | RegExp,
      options: SchemaPreOptions & { document: true, query: true },
      fn: PreUpdateOneMiddlewareFunction<T>
    ): this;
    pre<T = THydratedDocumentType | Query<any, any>>(
      method: 'deleteOne' | RegExp,
      options: SchemaPreOptions & { document: true, query: true },
      fn: PreDeleteOneMiddlewareFunction<T>
    ): this;
    // this = Document
    pre<T = THydratedDocumentType>(method: 'save', fn: PreSaveMiddlewareFunction<T>): this;
    pre<T = THydratedDocumentType, U = RawDocType>(method: 'init', fn: (this: T, doc: U) => void): this;
    pre<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], fn: PreMiddlewareFunction<T>): this;
    pre<T = THydratedDocumentType>(method: MongooseDistinctDocumentMiddleware|MongooseDistinctDocumentMiddleware[], options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
    pre<T = THydratedDocumentType>(
      method: 'updateOne' | RegExp,
      options: SchemaPreOptions & { document: true },
      fn: PreUpdateOneMiddlewareFunction<T>
    ): this;
    pre<T = THydratedDocumentType>(
      method: 'deleteOne' | RegExp,
      options: SchemaPreOptions & { document: true },
      fn: PreDeleteOneMiddlewareFunction<T>
    ): this;
    pre<T = THydratedDocumentType>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPreOptions & { document: true, query: false }, fn: PreMiddlewareFunction<T>): this;
    // this = Query
    pre<T = Query<any, any>>(method: MongooseDefaultQueryMiddleware|MongooseDefaultQueryMiddleware[], fn: PreMiddlewareFunction<T>): this;
    pre<T = Query<any, any>>(method: MongooseDistinctQueryMiddleware|MongooseDistinctQueryMiddleware[], options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
    pre<T = Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPreOptions & { document: false, query: true }, fn: PreMiddlewareFunction<T>): this;
    // this = Union of Document and Query, could be called with any of them
    pre<T = THydratedDocumentType|Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, options: SchemaPreOptions & { document: true, query: true }, fn: PreMiddlewareFunction<T>): this;
    pre<T = THydratedDocumentType|Query<any, any>>(method: MongooseQueryOrDocumentMiddleware | MongooseQueryOrDocumentMiddleware[] | RegExp, fn: PreMiddlewareFunction<T>): this;
    // method aggregate
    pre<T extends Aggregate<any>>(method: 'aggregate' | RegExp, fn: PreMiddlewareFunction<T>): this;
    /* method insertMany */
    pre<T = TModelType>(
      method: 'insertMany' | RegExp,
      fn: (
        this: T,
        next: (err?: CallbackError) => void,
        docs: any | Array<any>,
        options?: InsertManyOptions & { lean?: boolean }
      ) => void | Promise<void>
    ): this;
    /* method bulkWrite */
    pre<T = TModelType>(
      method: 'bulkWrite' | RegExp,
      fn: (
        this: T,
        next: (err?: CallbackError) => void,
        ops: Array<AnyBulkWriteOperation<any>>,
        options?: mongodb.BulkWriteOptions & MongooseBulkWriteOptions
      ) => void | Promise<void>
    ): this;
    /* method createCollection */
    pre<T = TModelType>(
      method: 'createCollection' | RegExp,
      fn: (
        this: T,
        next: (err?: CallbackError) => void,
        options?: mongodb.CreateCollectionOptions & Pick<SchemaOptions, 'expires'>
      ) => void | Promise<void>
    ): this;

    /** Object of currently defined query helpers on this schema. */
    query: TQueryHelpers;

    /** Adds a method call to the queue. */
    queue(name: string, args: any[]): this;

    /** Removes the given `path` (or [`paths`]). */
    remove(paths: string | Array<string>): this;

    /** Removes index by name or index spec */
    removeIndex(index: string | AnyObject): this;

    /** Returns an Array of path strings that are required by this schema. */
    requiredPaths(invalidate?: boolean): string[];

    /** Sets a schema option. */
    set<K extends keyof SchemaOptions>(key: K, value: SchemaOptions<DocType>[K], _tags?: any): this;

    /** Adds static "class" methods to Models compiled from this schema. */
    static<K extends keyof TStaticMethods>(name: K, fn: TStaticMethods[K]): this;
    static(obj: Partial<TStaticMethods> & { [name: string]: (this: TModelType, ...args: any[]) => any }): this;
    static(name: string, fn: (this: TModelType, ...args: any[]) => any): this;

    /** Object of currently defined statics on this schema. */
    statics: { [F in keyof TStaticMethods]: TStaticMethods[F] } &
    { [name: string]: (this: TModelType, ...args: any[]) => unknown };

    toJSONSchema(options?: { useBsonType?: boolean }): Record<string, any>;

    /** Creates a virtual type with the given name. */
    virtual<T = THydratedDocumentType>(
      name: keyof TVirtuals | string,
      options?: VirtualTypeOptions<T, DocType>
    ): VirtualType<T>;

    /** Object of currently defined virtuals on this schema */
    virtuals: TVirtuals;

    /** Returns the virtual type with the given `name`. */
    virtualpath<T = THydratedDocumentType>(name: string): VirtualType<T> | null;

    static ObjectId: typeof Schema.Types.ObjectId;
  }

  export type NumberSchemaDefinition = typeof Number | 'number' | 'Number' | typeof Schema.Types.Number | Schema.Types.Number;
  export type StringSchemaDefinition = typeof String | 'string' | 'String' | typeof Schema.Types.String | Schema.Types.String;
  export type BooleanSchemaDefinition = typeof Boolean | 'boolean' | 'Boolean' | typeof Schema.Types.Boolean | Schema.Types.Boolean;
  export type DateSchemaDefinition = DateConstructor | 'date' | 'Date' | typeof Schema.Types.Date | Schema.Types.Date;
  export type ObjectIdSchemaDefinition = 'ObjectId' | 'ObjectID' | typeof Schema.Types.ObjectId | Schema.Types.ObjectId | Types.ObjectId;
  export type BufferSchemaDefinition = typeof Buffer | 'buffer' | 'Buffer' | typeof Schema.Types.Buffer;
  export type Decimal128SchemaDefinition = 'decimal128' | 'Decimal128' | typeof Schema.Types.Decimal128 | Schema.Types.Decimal128 | Types.Decimal128;
  export type BigintSchemaDefinition = 'bigint' | 'BigInt' | typeof Schema.Types.BigInt | Schema.Types.BigInt | typeof BigInt | BigInt;
  export type UuidSchemaDefinition = 'uuid' | 'UUID' | typeof Schema.Types.UUID | Schema.Types.UUID;
  export type MapSchemaDefinition = MapConstructor | 'Map' | typeof Schema.Types.Map;
  export type UnionSchemaDefinition = 'Union' | 'union' | typeof Schema.Types.Union | Schema.Types.Union;
  export type DoubleSchemaDefinition = 'double' | 'Double' | typeof Schema.Types.Double | Schema.Types.Double;

  export type SchemaDefinitionWithBuiltInClass<T> = T extends number
    ? NumberSchemaDefinition
    : T extends string
      ? StringSchemaDefinition
      : T extends boolean
        ? BooleanSchemaDefinition
        : T extends NativeDate
          ? DateSchemaDefinition
          : (Function | string);

  export type SchemaDefinitionProperty<T = undefined, EnforcedDocType = any, THydratedDocumentType = HydratedDocument<EnforcedDocType>> =
    // ThisType intersection here avoids corrupting ThisType for SchemaTypeOptions (see test gh11828)
    | SchemaDefinitionWithBuiltInClass<T> & ThisType<EnforcedDocType>
    | SchemaTypeOptions<T extends undefined ? any : T, EnforcedDocType, THydratedDocumentType>
    | typeof SchemaType
    | Schema<any, any, any>
    | Schema<any, any, any>[]
    | SchemaTypeOptions<T extends undefined ? any : Unpacked<T>, EnforcedDocType, THydratedDocumentType>[]
    | Function[]
    | SchemaDefinition<T, EnforcedDocType, THydratedDocumentType>
    | SchemaDefinition<Unpacked<T>, EnforcedDocType, THydratedDocumentType>[]
    | typeof Schema.Types.Mixed
    | MixedSchemaTypeOptions<EnforcedDocType>;

  export type SchemaDefinition<T = undefined, EnforcedDocType = any, THydratedDocumentType = HydratedDocument<EnforcedDocType>> = T extends undefined
    ? { [path: string]: SchemaDefinitionProperty; }
    : { [path in keyof T]?: SchemaDefinitionProperty<T[path], EnforcedDocType, THydratedDocumentType>; };

  export type AnyArray<T> = T[] | ReadonlyArray<T>;
  export type ExtractMongooseArray<T> = T extends Types.Array<any> ? AnyArray<Unpacked<T>> : T;

  export interface MixedSchemaTypeOptions<EnforcedDocType> extends SchemaTypeOptions<Schema.Types.Mixed, EnforcedDocType> {
    type: typeof Schema.Types.Mixed;
  }

  export type RefType =
    | number
    | string
    | Buffer
    | undefined
    | Types.ObjectId
    | Types.Buffer
    | typeof Schema.Types.Number
    | typeof Schema.Types.String
    | typeof Schema.Types.Buffer
    | typeof Schema.Types.ObjectId
    | typeof Schema.Types.UUID;


  export type InferId<T> = mongodb.InferIdType<T>;

  export interface VirtualTypeOptions<HydratedDocType = Document, DocType = unknown> {
    /** If `ref` is not nullish, this becomes a populated virtual. */
    ref?: string | Function;

    /** The local field to populate on if this is a populated virtual. */
    localField?: string | ((this: HydratedDocType, doc: HydratedDocType) => string);

    /** The foreign field to populate on if this is a populated virtual. */
    foreignField?: string | ((this: HydratedDocType, doc: HydratedDocType) => string);

    /**
     * By default, a populated virtual is an array. If you set `justOne`,
     * the populated virtual will be a single doc or `null`.
     */
    justOne?: boolean;

    /** If you set this to `true`, Mongoose will call any custom getters you defined on this virtual. */
    getters?: boolean;

    /**
     * If you set this to `true`, `populate()` will set this virtual to the number of populated
     * documents, as opposed to the documents themselves, using `Query#countDocuments()`.
     */
    count?: boolean;

    /** Add an extra match condition to `populate()`. */
    match?: FilterQuery<any> | ((doc: Record<string, any>, virtual?: this) => Record<string, any> | null);

    /** Add a default `limit` to the `populate()` query. */
    limit?: number;

    /** Add a default `skip` to the `populate()` query. */
    skip?: number;

    /**
     * For legacy reasons, `limit` with `populate()` may give incorrect results because it only
     * executes a single query for every document being populated. If you set `perDocumentLimit`,
     * Mongoose will ensure correct `limit` per document by executing a separate query for each
     * document to `populate()`. For example, `.find().populate({ path: 'test', perDocumentLimit: 2 })`
     * will execute 2 additional queries if `.find()` returns 2 documents.
     */
    perDocumentLimit?: number;

    /** Additional options like `limit` and `lean`. */
    options?: QueryOptions<DocType> & { match?: AnyObject };

    /** If true and the given `name` is a direct child of an array, apply the virtual to the array rather than the elements. */
    applyToArray?: boolean;

    /** Additional options for plugins */
    [extra: string]: any;
  }

  export class VirtualType<HydratedDocType> {
    /** Applies getters to `value`. */
    applyGetters(value: any, doc: Document): any;

    /** Applies setters to `value`. */
    applySetters(value: any, doc: Document): any;

    /** Adds a custom getter to this virtual. */
    get<T = HydratedDocType>(fn: (this: T, value: any, virtualType: VirtualType<T>, doc: T) => any): this;

    /** Adds a custom setter to this virtual. */
    set<T = HydratedDocType>(fn: (this: T, value: any, virtualType: VirtualType<T>, doc: T) => void): this;
  }

  export type ReturnsNewDoc = { new: true } | { returnOriginal: false } | { returnDocument: 'after' };

  type ArrayOperators = { $slice: number | [number, number]; $elemMatch?: never } | { $elemMatch: Record<string, any>; $slice?: never };
  /**
   * This Type Assigns `Element | undefined` recursively to the `T` type.
   * if it is an array it will do this to the element of the array, if it is an object it will do this for the properties of the object.
   * `Element` is the truthy or falsy values that are going to be used as the value of the projection.(1 | true or 0 | false)
   * For the elements of the array we will use: `Element | `undefined` | `ArrayOperators`
   * @example
   * type CalculatedType = Projector<{ a: string, b: number, c: { d: string }, d: string[] }, true>
   * type CalculatedType = {
        a?: true | undefined;
        b?: true | undefined;
        c?: true | {
            d?: true | undefined;
        } | undefined;
        d?: true | ArrayOperators | undefined;
    }
  */
  type Projector<T, Element> = T extends Array<infer U>
    ? Projector<U, Element> | ArrayOperators
    : T extends TreatAsPrimitives
      ? Element
      : T extends Record<string, any>
        ? {
          [K in keyof T]?: T[K] extends Record<string, any> ? Projector<T[K], Element> | Element : Element;
        }
        : Element;
  type _IDType = { _id?: boolean | number };
  export type InclusionProjection<T> = IsItRecordAndNotAny<T> extends true
    ? Omit<Projector<WithLevel1NestedPaths<T>, boolean | number>, '_id'> & _IDType
    : AnyObject;
  export type ExclusionProjection<T> = IsItRecordAndNotAny<T> extends true
    ? Omit<Projector<WithLevel1NestedPaths<T>, false | 0>, '_id'> & _IDType
    : AnyObject;

  export type ProjectionType<T> = (InclusionProjection<T> & AnyObject)
    | (ExclusionProjection<T> & AnyObject)
    | string;
  export type SortValues = SortOrder;

  export type SortOrder = -1 | 1 | 'asc' | 'ascending' | 'desc' | 'descending';

  type _UpdateQuery<TSchema, AdditionalProperties = AnyObject> = {
    /** @see https://www.mongodb.com/docs/manual/reference/operator/update-field/ */
    $currentDate?: AnyKeys<TSchema> & AdditionalProperties;
    $inc?: AnyKeys<TSchema> & AdditionalProperties;
    $min?: AnyKeys<TSchema> & AdditionalProperties;
    $max?: AnyKeys<TSchema> & AdditionalProperties;
    $mul?: AnyKeys<TSchema> & AdditionalProperties;
    $rename?: Record<string, string>;
    $set?: AnyKeys<TSchema> & AdditionalProperties;
    $setOnInsert?: AnyKeys<TSchema> & AdditionalProperties;
    $unset?: AnyKeys<TSchema> & AdditionalProperties;

    /** @see https://www.mongodb.com/docs/manual/reference/operator/update-array/ */
    $addToSet?: AnyKeys<TSchema> & AdditionalProperties;
    $pop?: AnyKeys<TSchema> & AdditionalProperties;
    $pull?: AnyKeys<TSchema> & AdditionalProperties;
    $push?: AnyKeys<TSchema> & AdditionalProperties;
    $pullAll?: AnyKeys<TSchema> & AdditionalProperties;

    /** @see https://www.mongodb.com/docs/manual/reference/operator/update-bitwise/ */
    $bit?: AnyKeys<TSchema>;
  };

  export type UpdateWithAggregationPipeline = UpdateAggregationStage[];
  export type UpdateAggregationStage = { $addFields: any } |
  { $set: any } |
  { $project: any } |
  { $unset: any } |
  { $replaceRoot: any } |
  { $replaceWith: any };

  /**
   * Update query command to perform on the document
   * @example
   * ```js
   * { age: 30 }
   * ```
   */
  export type UpdateQuery<T> = AnyKeys<T> & _UpdateQuery<T> & AnyObject;

  /**
   * A more strict form of UpdateQuery that enforces updating only
   * known top-level properties.
   * @example
   * ```ts
   * function updateUser(_id: mongoose.Types.ObjectId, update: UpdateQueryKnownOnly<IUser>) {
   *   return User.updateOne({ _id }, update);
   * }
   * ```
   */
  export type UpdateQueryKnownOnly<T> = _UpdateQuery<T, {}>;

  export type FlattenMaps<T> = {
    [K in keyof T]: FlattenProperty<T[K]>;
  };

  export type BufferToBinaryProperty<T> = unknown extends Buffer
    ? T
    : T extends Buffer
      ? mongodb.Binary
      : T extends Types.DocumentArray<infer ItemType>
        ? Types.DocumentArray<BufferToBinary<ItemType>>
        : T extends Types.Subdocument<unknown, unknown, infer SubdocType>
          ? HydratedSingleSubdocument<BufferToBinary<SubdocType>>
          : BufferToBinary<T>;

  /**
   * Converts any Buffer properties into mongodb.Binary instances, which is what `lean()` returns
   */
   export type BufferToBinary<T> = unknown extends Buffer
     ? T
     : T extends Buffer
       ? mongodb.Binary
       : T extends Document
         ? T
         : T extends TreatAsPrimitives
           ? T
           : T extends Record<string, any>
             ? {
                 [K in keyof T]: BufferToBinaryProperty<T[K]>
               }
             : T;

  /**
  * Converts any Buffer properties into { type: 'buffer', data: [1, 2, 3] } format for JSON serialization
  */
  export type BufferToJSON<T> = unknown extends Buffer
    ? T
    : T extends Buffer
      ? { type: 'buffer', data: number[] }
      : T extends Document
        ? T
        : T extends TreatAsPrimitives
          ? T
          : T extends Record<string, any> ? {
            [K in keyof T]: T[K] extends Buffer
              ? { type: 'buffer', data: number[] }
              : T[K] extends Types.DocumentArray<infer ItemType>
                  ? Types.DocumentArray<BufferToBinary<ItemType>>
                  : T[K] extends Types.Subdocument<unknown, unknown, infer SubdocType>
                    ? HydratedSingleSubdocument<SubdocType>
                    : BufferToBinary<T[K]>;
          } : T;

  /**
   * Converts any UUID properties into strings for JSON serialization
   */
  export type UUIDToString<T> = T extends Types.UUID
    ? string
    : T extends mongodb.UUID
      ? string
      : T extends Document
        ? T
        : T extends TreatAsPrimitives
          ? T
          : T extends Record<string, any> ? {
            [K in keyof T]: T[K] extends Types.UUID
              ? string
              : T[K] extends mongodb.UUID
                ? string
                : T[K] extends Types.DocumentArray<infer ItemType>
                    ? Types.DocumentArray<UUIDToString<ItemType>>
                    : T[K] extends Types.Subdocument<unknown, unknown, infer SubdocType>
                      ? HydratedSingleSubdocument<UUIDToString<SubdocType>>
                      : UUIDToString<T[K]>;
          } : T;

  /**
   * Alias for UUIDToString for backwards compatibility.
   * @deprecated Use UUIDToString instead.
   */
  export type UUIDToJSON<T> = UUIDToString<T>;

  /**
   * Converts any ObjectId properties into strings for JSON serialization
   */
  export type ObjectIdToString<T> = T extends mongodb.ObjectId
    ? string
    : T extends Document
      ? T
      : T extends TreatAsPrimitives
        ? T
        : T extends Record<string, any> ? {
          [K in keyof T]: T[K] extends mongodb.ObjectId
            ? string
            : T[K] extends Types.DocumentArray<infer ItemType>
                ? Types.DocumentArray<ObjectIdToString<ItemType>>
                : T[K] extends Types.Subdocument<unknown, unknown, infer SubdocType>
                  ? HydratedSingleSubdocument<ObjectIdToString<SubdocType>>
                  : ObjectIdToString<T[K]>;
        } : T;

  /**
   * Converts any Date properties into strings for JSON serialization
   */
  export type DateToString<T> = T extends NativeDate
    ? string
    : T extends Document
      ? T
        : T extends TreatAsPrimitives
        ? T
        : T extends Record<string, any> ? {
          [K in keyof T]: T[K] extends NativeDate
            ? string
            : T[K] extends (NativeDate | null | undefined)
              ? string | null | undefined
              : T[K] extends Types.DocumentArray<infer ItemType>
                  ? Types.DocumentArray<DateToString<ItemType>>
                  : T[K] extends Types.Subdocument<unknown, unknown, infer SubdocType>
                    ? HydratedSingleSubdocument<DateToString<SubdocType>>
                    : DateToString<T[K]>;
        } : T;

  /**
   * Converts any Mongoose subdocuments (single nested or doc arrays) into POJO equivalents
   */
  export type SubdocsToPOJOs<T> = T extends Document
    ? T
    : T extends TreatAsPrimitives
      ? T
      : T extends Record<string, any> ? {
        [K in keyof T]: T[K] extends Types.DocumentArray<infer ItemType>
          ? ItemType[]
          : T[K] extends Types.Subdocument<unknown, unknown, infer SubdocType>
            ? SubdocType
            : SubdocsToPOJOs<T[K]>;
      } : T;

  export type JSONSerialized<T> = SubdocsToPOJOs<
    FlattenMaps<
      BufferToJSON<
        ObjectIdToString<
          UUIDToString<
            DateToString<T>
          >
        >
      >
    >
  >;

  /**
   * Helper types for computing toObject/toJSON return types based on options.
   * These compose transforms conditionally to avoid combinatorial explosion of overloads.
   */
  type ApplyVirtuals<T, TVirtuals, O> =
    O extends { virtuals: true } ? T & TVirtuals : T;

  type GetVersionKeyName<TSchemaOptions> =
    TSchemaOptions extends { versionKey: infer VK }
      ? VK extends string ? VK : '__v'
      : '__v';

  type ApplyVersionKey<T, O, TSchemaOptions = {}> =
    O extends { versionKey: false } ? Omit<T, GetVersionKeyName<TSchemaOptions>> : T;

  /**
   * Single-pass type that applies all flatten transforms (flattenMaps, flattenObjectIds, flattenUUIDs)
   * in one recursive traversal. This avoids TypeScript's "union type too complex" error that occurs
   * when nesting separate recursive transform types.
   *
   * By handling all transforms in one pass, we correctly handle ObjectIds/UUIDs nested inside Maps
   * since we recurse into Map values during the same traversal that converts ObjectIds/UUIDs.
   */
  type ApplyFlattenTransforms<T, O> =
    // Handle ObjectId first (before TreatAsPrimitives since ObjectId is in TreatAsPrimitives)
    T extends mongodb.ObjectId
      ? O extends { flattenObjectIds: true } ? string : T
    // Handle UUID (both Types.UUID and mongodb.UUID)
    : T extends Types.UUID
      ? O extends { flattenUUIDs: true } ? string : T
    : T extends mongodb.UUID
      ? O extends { flattenUUIDs: true } ? string : T
    // Handle Map - flatten to Record and recurse into values
    : T extends Map<any, infer V>
      ? O extends { flattenMaps: true }
        ? Record<string, ApplyFlattenTransforms<V, O>>
        : T
    // Don't recurse into Documents
    : T extends Document
      ? T
    // Don't modify primitives
    : T extends TreatAsPrimitives
      ? T
    // Handle DocumentArray - recurse into items
    : T extends Types.DocumentArray<infer ItemType>
      ? Types.DocumentArray<ApplyFlattenTransforms<ItemType, O>>
    // Handle Subdocument - recurse into subdoc type
    : T extends Types.Subdocument<unknown, unknown, infer SubdocType>
      ? HydratedSingleSubdocument<ApplyFlattenTransforms<SubdocType, O>>
    // Handle regular objects - recurse into properties
    : T extends Record<string, any>
      ? { [K in keyof T]: ApplyFlattenTransforms<T[K], O> }
    : T;

  /**
   * Computes the return type of toObject/toJSON based on the provided options.
   * Uses a single-pass transform for flatten operations to correctly handle all combinations.
   */
  export type ToObjectReturnType<DocType, TVirtuals, O extends ToObjectOptions, TSchemaOptions = {}> =
    ApplyVersionKey<
      Default__v<
        ApplyFlattenTransforms<
          ApplyVirtuals<Require_id<DocType>, TVirtuals, O>,
          O
        >,
        TSchemaOptions
      >,
      O,
      TSchemaOptions
    >;

  /**
   * Separate type is needed for properties of union type (for example, Types.DocumentArray | undefined) to apply conditional check to each member of it
   * https://www.typescriptlang.org/docs/handbook/2/conditional-types.html#distributive-conditional-types
   */
  type FlattenProperty<T> = T extends Map<any, infer V>
      ? Record<string, V> : T extends TreatAsPrimitives
      ? T : T extends Document ? T : T extends Types.DocumentArray<infer ItemType>
        ? Types.DocumentArray<FlattenMaps<ItemType>> : FlattenMaps<T>;

  export type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
  export type TreatAsPrimitives = actualPrimitives | NativeDate | RegExp | symbol | Error | BigInt | Types.ObjectId | Buffer | Function | mongodb.Binary | mongodb.ClientSession;

  export type SchemaDefinitionType<T> = T extends Document ? Omit<T, Exclude<keyof Document, '_id' | 'id' | '__v'>> : T;

  /* for ts-mongoose */
  export class mquery { }

  export function overwriteMiddlewareResult(val: any): Kareem.OverwriteMiddlewareResult;

  export function skipMiddlewareFunction(val: any): Kareem.SkipWrappedFunction;

  export default mongoose;
}
