"use strict";

const { validateArguments } = require("@validatem/core");
const required = require("@validatem/required");
const either = require("@validatem/either");

const node = require("../ast-node");
const unreachable = require("../unreachable");
const tagAsType = require("../validators/tag-as-type");

module.exports = function (operations) {
	const isExpression = require("../validators/operations/is-expression")(operations);
	const isCondition = require("../validators/operations/is-condition")(operations);
	
	return function not(_expression) {
		let [ expression ] = validateArguments(arguments, {
			expression: [ required, either([
				[ isExpression, tagAsType("expression") ],
				[ isCondition, tagAsType("condition") ],
			])]
		});

		// FIXME: rename expression to something clearer, that indicates its relationship to conditions?

		if (expression.type === "expression") {
			return node({ type: "notExpression", expression: expression.value });
		} else if (expression.type === "condition") {
			return node({ type: "notCondition", condition: expression.value });
		} else {
			unreachable(`Invalid tagged type '${expression.type}'`);
		}
	};
};