import type { Algebra } from '@comunica/utils-algebra';
import type * as RDF from '@rdfjs/types';
import type { AsyncIterator } from 'asynciterator';
import type { BindingsStream } from './Bindings';
import type { IActionContext } from './IActionContext';
import type { QueryAlgebraContext, QueryStringContext } from './IQueryContext';
import type { IQueryExplained, QueryEnhanced, QueryExplainMode } from './IQueryOperationResult';
import type { QuerySourceUnidentified } from './IQuerySource';
export type QueryFormatType = string | Algebra.Operation;
export type SourceType = QuerySourceUnidentified;
export type QueryType = QueryEnhanced & {
    context?: IActionContext;
};
/**
 * Base interface for a Comunica query engine.
 */
export interface IQueryEngine<QueryStringContextInner extends RDF.QueryStringContext = QueryStringContext, QueryAlgebraContextInner extends RDF.QueryAlgebraContext = QueryAlgebraContext> extends RDF.StringQueryable<RDF.AllMetadataSupport, QueryStringContextInner>, RDF.AlgebraQueryable<Algebra.Operation, RDF.AllMetadataSupport, QueryAlgebraContextInner>, RDF.StringSparqlQueryable<RDF.SparqlResultSupport, QueryStringContextInner>, RDF.AlgebraSparqlQueryable<Algebra.Operation, RDF.SparqlResultSupport, QueryAlgebraContextInner> {
    /**
     * Query the bindings results of a SELECT query.
     * @param query A query string or algebra object.
     *              Algebra objects must not contain blank nodes. They should be converted to variables.
     * @param context A context.
     */
    queryBindings: <QueryFormatTypeInner extends QueryFormatType>(query: QueryFormatTypeInner, context?: QueryFormatTypeInner extends string ? QueryStringContextInner : QueryAlgebraContextInner) => Promise<BindingsStream>;
    /**
     * Query the quad results of a CONSTRUCT or DESCRIBE query.
     * @param query A query string or algebra object.
     *              Algebra objects must not contain blank nodes. They should be converted to variables.
     * @param context A context.
     */
    queryQuads: <QueryFormatTypeInner extends QueryFormatType>(query: QueryFormatTypeInner, context?: QueryFormatTypeInner extends string ? QueryStringContextInner : QueryAlgebraContextInner) => Promise<AsyncIterator<RDF.Quad> & RDF.ResultStream<RDF.Quad>>;
    /**
     * Query the boolean result of an ASK query.
     * @param query A query string or algebra object.
     *              Algebra objects must not contain blank nodes. They should be converted to variables.
     * @param context A context.
     */
    queryBoolean: <QueryFormatTypeInner extends QueryFormatType>(query: QueryFormatTypeInner, context?: QueryFormatTypeInner extends string ? QueryStringContextInner : QueryAlgebraContextInner) => Promise<boolean>;
    /**
     * Execute an UPDATE query.
     * @param query A query string or algebra object.
     *              Algebra objects must not contain blank nodes. They should be converted to variables.
     * @param context A context.
     */
    queryVoid: <QueryFormatTypeInner extends QueryFormatType>(query: QueryFormatTypeInner, context?: QueryFormatTypeInner extends string ? QueryStringContextInner : QueryAlgebraContextInner) => Promise<void>;
    /**
     * Initiate a given query.
     * This will produce a future to a query result, which has to be executed to obtain the query results.
     * This can reject given an unsupported or invalid query.
     *
     * This method is prefered in case you don't know beforehand what type of query will be executed,
     * or if you require access to the metadata of the results.
     *
     * @param query A query string or algebra object.
     *              Algebra objects must not contain blank nodes. They should be converted to variables.
     * @param context A context.
     */
    query: <QueryFormatTypeInner extends QueryFormatType>(query: QueryFormatTypeInner, context?: QueryFormatTypeInner extends string ? QueryStringContextInner : QueryAlgebraContextInner) => Promise<QueryType>;
    /**
     * Explain the given query
     * @param {string | Algebra.Operation} query A query string or algebra.
     *                                           Algebra objects must not contain blank nodes.
     *                                           They should be converted to variables.
     * @param context A query context.
     * @param explainMode The explain mode.
     * @return {Promise<IQueryExplained>}
     *  A promise that resolves to the query output.
     */
    explain: <QueryFormatTypeInner extends QueryFormatType>(query: QueryFormatTypeInner, context: QueryFormatTypeInner extends string ? QueryStringContextInner : QueryAlgebraContextInner, explainMode: QueryExplainMode) => Promise<IQueryExplained>;
    /**
     * @param context An optional context.
     * @return {Promise<{[p: string]: number}>} All available SPARQL (weighted) result media types.
     */
    getResultMediaTypes: (context?: IActionContext) => Promise<Record<string, number>>;
    /**
     * @param context An optional context.
     * @return {Promise<{[p: string]: number}>} All available SPARQL result media type formats.
     */
    getResultMediaTypeFormats: (context?: IActionContext) => Promise<Record<string, string>>;
    /**
     * Convert a query result to a string stream based on a certain media type.
     * @param {QueryType} queryResult A query result.
     * @param {string} mediaType A media type.
     * @param {IActionContext} context An optional context.
     * @return {Promise<IActorQueryResultSerializeOutput>} A text stream.
     */
    resultToString: (queryResult: QueryType, mediaType?: string, context?: any) => any;
    /**
     * Invalidate all internal caches related to the given page URL.
     * If no page URL is given, then all pages will be invalidated.
     * @param {string} url The page URL to invalidate.
     * @return {Promise<any>} A promise resolving when the caches have been invalidated.
     */
    invalidateHttpCache: (url?: string) => Promise<any>;
}