// this file provides a well-typed wrapper about the (unchecked) PegJS parser.

import { Expression, Pattern } from './types';

declare const require: (path: string) => any; // eslint-disable-line

const colorExpressions: any = (require)('./colorExpressions.js'); // eslint-disable-line

export function parseExpression(expression: string): Expression {
    try {
        return colorExpressions.parse(expression, { startRule: 'expression' });
    } catch (e: unknown) {
        const message = typeof (e) === "object" && e !== null && "message" in e && typeof (e.message) === "string" && e.message;
        throw new Error(`Failed to parse "${expression}" as expression: ${message ?? ""}`);
    }
}

export function parseInteger(expression: string): number {
    try {
        return colorExpressions.parse(expression, { startRule: 'integer' });
    } catch (e) {
        const message = typeof (e) === "object" && e !== null && "message" in e && typeof (e.message) === "string" && e.message;
        throw new Error(`Failed to parse "${expression}" as integer: ${message ?? ""}`);
    }
}

export function parsePattern(pattern: string): Pattern {
    try {
        return colorExpressions.parse(pattern, { startRule: 'pattern' });
    } catch (e) {
        const message = typeof (e) === "object" && e !== null && "message" in e && typeof (e.message) === "string" && e.message;
        throw new Error(`Failed to parse "${pattern}" as pattern: ${message ?? ""}`);
    }
}