/* eslint no-unused-vars: 0 */

"use strict";

const ast = require( "../ast" );
const GrammarError = require( "../grammar-error" );
const opcodes = require( "./opcodes" );
const parser = require( "../parser" );
const util = require( "../util" );

function fatal( message, location ) {

    if ( typeof location !== "undefined" )

        throw new GrammarError( message, location );

    throw new Error( message );

}

class Session {

    constructor( config ) {

        config = typeof config !== "undefined" ? config : {};

        this.opcodes = config.opcodes || opcodes;
        this.parser = config.parser || parser;
        this.passes = config.passes || {};
        this.visitor = config.visitor || ast.visitor;
        this.vm = config.vm || {
            runInContext: util.runInContext
        };

        if ( typeof config.warn === "function" ) this.warn = config.warn;
        if ( typeof config.error === "function" ) this.error = config.error;

        Object.defineProperty( this, "fatal", { value: fatal } );

    }

    parse( input, options ) {

        return this.parser.parse( input, options );

    }

    buildVisitor( functions ) {

        return this.visitor.build( functions );

    }

    warn( message, location ) {}

    error( message, location ) {

        fatal( message, location );

    }

}

module.exports = Session;