// Type definitions for express-graphql
// Project: https://www.npmjs.org/package/express-graphql
// Definitions by: Isman Usoh <https://github.com/isman-usoh>, Nitin Tutlani <https://github.com/nitintutlani>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped

/// <reference path="../express/express.d.ts" />

declare module "express-graphql" {
    import { Request, Response } from "express";

    namespace graphqlHTTP {
        /**
         * Used to configure the graphQLHTTP middleware by providing a schema
         * and other configuration options.
         */
        export type Options = ((req:Request) => OptionsObj) | OptionsObj
        export type OptionsObj = {
            /**
             * A GraphQL schema from graphql-js.
             */
            schema:Object,

            /**
             * A value to pass as the context to the graphql() function.
             */
            context?:Object,

            /**
             * An object to pass as the rootValue to the graphql() function.
             */
            rootValue?:Object,

            /**
             * A boolean to configure whether the output should be pretty-printed.
             */
            pretty?:boolean,

            /**
             * An optional function which will be used to format any errors produced by
             * fulfilling a GraphQL operation. If no function is provided, GraphQL's
             * default spec-compliant `formatError` function will be used.
             */
            formatError?:Function,

            /**
             * A boolean to optionally enable GraphiQL mode.
             */
            graphiql?:boolean,
        };

        type Middleware = (request:Request, response:Response) => void;
    }

    /**
     * Middleware for express; takes an options object or function as input to
     * configure behavior, and returns an express middleware.
     */
    function graphqlHTTP(options: graphqlHTTP.Options): graphqlHTTP.Middleware;
    export = graphqlHTTP;
}