import { DocumentNode } from "../language/ast";
import { GraphQLSchema } from "../type/schema";
import { GraphQLSchemaValidationOptions } from "../type/schema";

interface Options extends GraphQLSchemaValidationOptions {
    /**
     * Descriptions are defined as preceding string literals, however an older
     * experimental version of the SDL supported preceding comments as
     * descriptions. Set to true to enable this deprecated behavior.
     * This option is provided to ease adoption and will be removed in v16.
     *
     * Default: false
     */
    commentDescriptions?: boolean;

    /**
     * Set to true to assume the SDL is valid.
     *
     * Default: false
     */
    assumeValidSDL?: boolean;
}

/**
 * Produces a new schema given an existing schema and a document which may
 * contain GraphQL type extensions and definitions. The original schema will
 * remain unaltered.
 *
 * Because a schema represents a graph of references, a schema cannot be
 * extended without effectively making an entire copy. We do not know until it's
 * too late if subgraphs remain unchanged.
 *
 * This algorithm copies the provided schema, applying extensions while
 * producing the copy. The original schema remains unaltered.
 *
 * Accepts options as a third argument:
 *
 *    - commentDescriptions:
 *        Provide true to use preceding comments as the description.
 *
 */
export function extendSchema(schema: GraphQLSchema, documentAST: DocumentNode, options?: Options): GraphQLSchema;