"use strict";

const omitKeys = require("./omit-keys");
const reservedProperties = require("../reserved-properties");
const getChain = require("../get-chain");

let Context = Symbol("Context");

module.exports = function getContext(error) {
	if (error[Context] != null) {
		return error[Context];
	} else {
		let contexts = getChain(error)
			.reverse()
			.map((item) => omitKeys(item, reservedProperties));

		let combinedContext = Object.assign({}, ... contexts);

		error[Context] = combinedContext;
		return combinedContext;
	}
};