import type { GraphQLSchema } from 'graphql';
import type { SchemaManagerHost } from './types';
export type SchemaBuildErrorInfo = {
    message: string;
    fileName: string;
    fileContent: string;
    locations?: ReadonlyArray<{
        line: number;
        character: number;
    }>;
};
export type OnChangeCallback = (errors: SchemaBuildErrorInfo[] | null, schema: GraphQLSchema | null) => void;
export declare abstract class SchemaManager {
    protected _host: SchemaManagerHost;
    private _onChanges;
    private _extensionManager;
    constructor(_host: SchemaManagerHost);
    abstract getBaseSchema(): GraphQLSchema | null;
    protected abstract waitBaseSchema(): Promise<GraphQLSchema | null>;
    protected abstract startWatch(interval?: number): void;
    start(interval?: number): void;
    getSchema(): {
        schema: GraphQLSchema | null;
        errors: SchemaBuildErrorInfo[] | null;
    };
    waitSchema(): Promise<{
        schema: GraphQLSchema | null;
        errors: SchemaBuildErrorInfo[] | null;
    }>;
    registerOnChange(cb: OnChangeCallback): () => void;
    protected emitChange(): void;
    protected log(msg: string): void;
}
export declare class NoopSchemaManager extends SchemaManager {
    startWatch(): void;
    waitBaseSchema(): Promise<null>;
    getBaseSchema(): null;
}