@woosh/meep-engine/src/core/model/object/compareValues.js

Pure JavaScript game engine. Fully featured and production ready.

import { array_compare } from "../../collection/array/array_compare.js";
import { extractFunctionBody } from "../../function/extractFunctionBody.js";
import { compareBooleans } from "../../primitives/boolean/compareBooleans.js";
import { number_compare_ascending } from "../../primitives/numbers/number_compare_ascending.js";
import { compareStrings } from "../../primitives/strings/compareStrings.js";

/**
 *
 * @param {*} a
 * @param {*} b
 * @returns {number}
 */
export function compareValues(a, b) {
    if (a === b) {
        return 0;
    }

    const aType = typeof a;
    const bType = typeof b;

    if (aType !== bType) {
        return compareStrings(aType, bType);
    }

    if (aType === "string") {
        return compareStrings(a, b);
    } else if (aType === "number") {
        return number_compare_ascending(a, b);
    } else if (aType === "boolean") {
        return compareBooleans(a, b);
    } else if (aType === "function") {
        return compareStrings(extractFunctionBody(a), extractFunctionBody(b));
    } else if (aType === "object") {
        if (a === null) {
            if (b !== null) {
                return -1;
            } else {
                return 0;
            }
        } else if (b === null) {
            return 1;
        }

        if (Array.isArray(a) && Array.isArray(b)) {
            return array_compare(a, b, compareValues);
        }

        const aKeys = Object.keys(a);
        const bKeys = Object.keys(b);

        const dKeys = array_compare(aKeys, bKeys, compareStrings);

        if (dKeys !== 0) {
            return dKeys;
        }

        for (let p in a) {
            const d = compareValues(a[p], b[p]);

            if (d !== 0) {
                return d;
            }
        }
    }

    return 0;
}