import Logger from "../../../common/logger";

export default class Utilities {
    /**
     * Generates an automatically memoizing version of an object.
     * @author Zerebos
     * @param {Object} object - object to memoize
     * @returns {Proxy} the proxy to the object that memoizes properties
     */
    static memoizeObject(object) {
        const proxy = new Proxy(object, {
            get: function(obj, mod) {
                if (!obj.hasOwnProperty(mod)) return undefined;
                if (Object.getOwnPropertyDescriptor(obj, mod).get) {
                    const value = obj[mod];
                    delete obj[mod];
                    obj[mod] = value;
                }
                return obj[mod];
            },
            set: function(obj, mod, value) {
                if (obj.hasOwnProperty(mod)) return Logger.error("MemoizedObject", "Trying to overwrite existing property");
                obj[mod] = value;
                return obj[mod];
            }
        });

        Object.defineProperty(proxy, "hasOwnProperty", {value: function(prop) {
            return this[prop] !== undefined;
        }});

        return proxy;
    }

    /**
     * Deep extends an object with a set of other objects. Objects later in the list
     * of `extenders` have priority, that is to say if one sets a key to be a primitive,
     * it will be overwritten with the next one with the same key. If it is an object,
     * and the keys match, the object is extended. This happens recursively.
     * @param {object} extendee - Object to be extended
     * @param {...object} extenders - Objects to extend with
     * @returns {object} - A reference to `extendee`
     */
    static extend(extendee, ...extenders) {
        for (let i = 0; i < extenders.length; i++) {
            for (const key in extenders[i]) {
                if (extenders[i].hasOwnProperty(key)) {
                    if (typeof extendee[key] === "object" && typeof extenders[i][key] === "object") {
                        this.extend(extendee[key], extenders[i][key]);
                    }
                    else if (typeof extenders[i][key] === "object") {
                        extendee[key] = {};
                        this.extend(extendee[key], extenders[i][key]);
                    }
                    else {
                        extendee[key] = extenders[i][key];
                    }
                }
            }
        }
        return extendee;
    }

    /**
     * Deep extends an object with a set of other objects. Objects later in the list
     * of `extenders` have priority, that is to say if one sets a key to be a primitive,
     * it will be overwritten with the next one with the same key. If it is an object,
     * and the keys match, the object is extended. This happens recursively.
     * @param {object} extendee - Object to be extended
     * @param {...object} extenders - Objects to extend with
     * @returns {object} - A reference to `extendee`
     */
    static extendTruthy(extendee, ...extenders) {
        for (let i = 0; i < extenders.length; i++) {
            for (const key in extenders[i]) {
                if (extenders[i].hasOwnProperty(key)) {
                    if (typeof extendee[key] === "object" && typeof extenders[i][key] === "object") {
                        this.extendTruthy(extendee[key], extenders[i][key]);
                    }
                    else if (typeof extenders[i][key] === "object") {
                        extendee[key] = {};
                        this.extendTruthy(extendee[key], extenders[i][key]);
                    }
                    else if (extenders[i][key]) {
                        extendee[key] = extenders[i][key];
                    }
                }
            }
        }
        return extendee;
    }

    /**
     * Format strings with placeholders (`{{placeholder}}`) into full strings.
     * Quick example: `PluginUtilities.formatString("Hello, {{user}}", {user: "Zerebos"})`
     * would return "Hello, Zerebos".
     * @param {string} string - string to format
     * @param {object} values - object literal of placeholders to replacements
     * @returns {string} the properly formatted string
     */
    static formatString(string, values) {
        for (const val in values) {
            let replacement = values[val];
            if (Array.isArray(replacement)) replacement = JSON.stringify(replacement);
            if (typeof(replacement) === "object" && replacement !== null) replacement = replacement.toString();
            string = string.replace(new RegExp(`{{${val}}}`, "g"), replacement);
        }
        return string;
    }

    /**
     * Finds a value, subobject, or array from a tree that matches a specific filter. This is a DFS.
     * @param {object} tree Tree that should be walked
     * @param {callable} searchFilter Filter to check against each object and subobject
     * @param {object} options Additional options to customize the search
     * @param {Array<string>|null} [options.walkable=null] Array of strings to use as keys that are allowed to be walked on. Null value indicates all keys are walkable
     * @param {Array<string>} [options.ignore=[]] Array of strings to use as keys to exclude from the search, most helpful when `walkable = null`.
     */
    static findInTree(tree, searchFilter, {walkable = null, ignore = []} = {}) {
        if (typeof searchFilter === "string") {
            if (tree.hasOwnProperty(searchFilter)) return tree[searchFilter];
        }
        else if (searchFilter(tree)) {
            return tree;
        }

        if (typeof tree !== "object" || tree == null) return undefined;

        let tempReturn;
        if (tree instanceof Array) {
            for (const value of tree) {
                tempReturn = this.findInTree(value, searchFilter, {walkable, ignore});
                if (typeof tempReturn != "undefined") return tempReturn;
            }
        }
        else {
            const toWalk = walkable == null ? Object.keys(tree) : walkable;
            for (const key of toWalk) {
                if (typeof(tree[key]) == "undefined" || ignore.includes(key)) continue;
                tempReturn = this.findInTree(tree[key], searchFilter, {walkable, ignore});
                if (typeof tempReturn != "undefined") return tempReturn;
            }
        }
        return tempReturn;
    }

    /**
     * Returns a function, that, as long as it continues to be invoked, will not
     * be triggered. The function will be called after it stops being called for
     * N milliseconds.
     * 
     * Adapted from the version by David Walsh (https://davidwalsh.name/javascript-debounce-function)
     * 
     * @param {function} executor 
     * @param {number} delay 
     */
     static debounce(executor, delay) {
        let timeout;
        return function(...args) {
            const callback = () => {
                timeout = null;
                Reflect.apply(executor, null, args);
            };
            clearTimeout(timeout);
            timeout = setTimeout(callback, delay);
        };
    }

    /**
     * Takes a string of html and escapes it using the brower's own escaping mechanism.
     * @param {String} html - html to be escaped
     */
    static escapeHTML(html) {
        const textNode = document.createTextNode("");
        const spanElement = document.createElement("span");
        spanElement.append(textNode);
        textNode.nodeValue = html;
        return spanElement.innerHTML;
    }

    /**
     * Builds a classname string from any number of arguments. This includes arrays and objects.
     * When given an array all values from the array are added to the list.
     * When given an object they keys are added as the classnames if the value is truthy.
     * Copyright (c) 2018 Jed Watson https://github.com/JedWatson/classnames MIT License
     * @param {...Any} argument - anything that should be used to add classnames.
     */
    static className() {
        const classes = [];
        const hasOwn = {}.hasOwnProperty;

        for (let i = 0; i < arguments.length; i++) {
            const arg = arguments[i];
            if (!arg) continue;

            const argType = typeof arg;

            if (argType === "string" || argType === "number") {
                classes.push(arg);
            }
            else if (Array.isArray(arg) && arg.length) {
                const inner = this.classNames.apply(null, arg);
                if (inner) {
                    classes.push(inner);
                }
            }
            else if (argType === "object") {
                for (const key in arg) {
                    if (hasOwn.call(arg, key) && arg[key]) {
                        classes.push(key);
                    }
                }
            }
        }

        return classes.join(" ");
    }
}