export function graphql(
  resolver: Resolver,
  document: DocumentNode,
  rootValue?: any,
  contextValue?: any,
  variableValues?: VariableMap,
  execOptions: ExecOptions = {},
) {
  const mainDefinition = getMainDefinition(document);

  const fragments = getFragmentDefinitions(document);
  const fragmentMap = createFragmentMap(fragments);

  const resultMapper = execOptions.resultMapper;

  // Default matcher always matches all fragments
  const fragmentMatcher = execOptions.fragmentMatcher || (() => true);

  const execContext: ExecContext = {
    fragmentMap,
    contextValue,
    variableValues,
    resultMapper,
    resolver,
    fragmentMatcher,
  };

  return executeSelectionSet(
    mainDefinition.selectionSet,
    rootValue,
    execContext,
  );
}

  /**
   * Based on graphql function from graphql-js:
   *
   * graphql(
   *   schema: GraphQLSchema,
   *   requestString: string,
   *   rootValue?: ?any,
   *   contextValue?: ?any,
   *   variableValues?: ?{[key: string]: any},
   *   operationName?: ?string
   * ): Promise<GraphQLResult>
   *
   * The default export as of graphql-anywhere is sync as of 4.0,
   * but below is an exported alternative that is async.
   * In the 5.0 version, this will be the only export again
   * and it will be async
   *
   */
  private executeStoreQuery({
    query,
    rootValue,
    contextValue,
    variableValues,
    // Default matcher always matches all fragments
    fragmentMatcher = defaultFragmentMatcher,
  }: ExecStoreQueryOptions): ExecResult {
    const mainDefinition = getMainDefinition(query);
    const fragments = getFragmentDefinitions(query);
    const fragmentMap = createFragmentMap(fragments);
    const execContext: ExecContext = {
      query,
      fragmentMap,
      contextValue,
      variableValues,
      fragmentMatcher,
    };

    return this.executeSelectionSet({
      selectionSet: mainDefinition.selectionSet,
      rootValue,
      execContext,
    });
  }

function storeRoundtrip(query: DocumentNode, result: any, variables = {}) {
  const fragmentMap = createFragmentMap(getFragmentDefinitions(query));
  const store = writeQueryToStore({
    result,
    query,
    variables,
    fragmentMap,
  });

  const reconstructedResult = readQueryFromStore({
    store,
    query,
    variables,
    fragmentMatcherFunction,
  });

  expect(reconstructedResult).toEqual(result);
}

  private async resolveDocument<TData>(
    document: DocumentNode,
    rootValue: TData,
    context: any = {},
    variables: VariableMap = {},
    fragmentMatcher: FragmentMatcher = () => true,
    onlyRunForcedResolvers: boolean = false,
  ) {
    const mainDefinition = getMainDefinition(document);
    const fragments = getFragmentDefinitions(document);
    const fragmentMap = createFragmentMap(fragments);

    const definitionOperation = (mainDefinition as OperationDefinitionNode)
      .operation;

    const defaultOperationType = definitionOperation
      ? capitalizeFirstLetter(definitionOperation)
      : 'Query';

    const { cache, client } = this;
    const execContext: ExecContext = {
      fragmentMap,
      context: {
        ...context,
        cache,
        client,
      },
      variables,
      fragmentMatcher,
      defaultOperationType,
      exportedVariables: {},
      onlyRunForcedResolvers,
    };

    return this.resolveSelectionSet(
      mainDefinition.selectionSet,
      rootValue,
      execContext,
    ).then(result => ({
      result,
      exportedVariables: execContext.exportedVariables,
    }));
  }