GM storage wrapper

simple wrapper for GM_storage with added functions

此脚本不应直接安装。它是供其他脚本使用的外部库,要使用该库请加入元指令 // @require https://update.gf.qytechs.cn/scripts/38717/253024/GM%20storage%20wrapper.js

您需要先安装一个扩展,例如 篡改猴Greasemonkey暴力猴,之后才能安装此脚本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安装一个扩展,例如 篡改猴暴力猴,之后才能安装此脚本。

您需要先安装一个扩展,例如 篡改猴Userscripts ,之后才能安装此脚本。

您需要先安装一款用户脚本管理器扩展,例如 Tampermonkey,才能安装此脚本。

您需要先安装用户脚本管理器扩展后才能安装此脚本。

(我已经安装了用户脚本管理器,让我安装!)

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

(我已经安装了用户样式管理器,让我安装!)

/*jshint esversion: 6 */
// ==UserScript==
// @name           GM storage wrapper
// @version        1.0
// @description    simple wrapper for GM_storage with added functions
// ==/UserScript==

    var gmStorageWrapper = {
        options : {
            prefix : ''
        },
        // “Set” means “add if absent, replace if present.”
        set : function(key, value) {
            let storageVals = this.read(key);

            if (typeof storageVals === 'undefined' || !storageVals) {
                // add if absent
                return this.add(key, value);
            } else {
                // replace if present
                this.write(key, value);
                return true;
            }
        },
        // “Add” means “add if absent, do nothing if present” (if a uniquing collection).
        add : function(key, value) {
            let storageVals = this.read(key, false);

            if (typeof storageVals === 'undefined' || !storageVals) {
                this.write(key, value);
                return true;
            } else {
                if (this._isArray(storageVals)) { // is array
                    let index = storageVals.indexOf(value);

                    if (index !== -1) {
                        // do nothing if present
                        return false;
                    } else {
                        // add if absent
                        storageVals.push(value);
                        this.write(key, storageVals);
                        return true;
                    }
                } else if (this._isObject(storageVals)) { // is object
                    // merge obj value on obj
                    let result,
                        objToMerge = value;

                    result = Object.assign(storageVals, objToMerge);
                    this.write(key, result);
                    return false;
                }
                return false;
            }
        },
        // “Replace” means “replace if present, do nothing if absent.”
        replace : function(key, itemFind, itemReplacement) {
            let storageVals = this.read(key, false);

            if (typeof storageVals === 'undefined' || !storageVals) {
                // do nothing if absent
                return false;
            } else {
                if (this._isArray(storageVals)) { // is Array
                    let index = storageVals.indexOf(itemFind);

                    if (index !== -1) {
                        // replace if present
                        storageVals[index] = itemReplacement;
                        this.write(key, storageVals);
                        return true;
                    } else {
                        // do nothing if absent
                        return false;
                    }
                } else if (this._isObject(storageVals)) {
                    // is Object
                    // replace property's value
                    storageVals[itemFind] = itemReplacement;
                    this.write(key, storageVals);
                    return true;
                }
                return false;
            }
        },
        // “Remove” means “remove if present, do nothing if absent.”
        remove : function(key, value) {
            if (typeof value === 'undefined') { // remove key
                this.delete(key);
                return true;
            } else { // value present
                let storageVals = this.read(key);

                if (typeof storageVals === 'undefined' || !storageVals) {
                    return true;
                } else {
                    if (this._isArray(storageVals)) { // is Array
                        let index = storageVals.indexOf(value);

                        if (index !== -1) {
                            // remove if present
                            storageVals.splice(index, 1);
                            this.write(key, storageVals);
                            return true;
                        } else {
                            // do nothing if absent
                            return false;
                        }
                    } else if (this._isObject(storageVals)) { // is Object
                        let property = value;

                        delete storageVals[property];
                        this.write(key, storageVals);
                        return true;
                    }
                    return false;
                }
            }
        },
        get : function(key, defaultValue) {
            return this.read(key, defaultValue);
        },

        // GM storage API
        read : function(key, defaultValue) {
            return this.unserialize(GM_getValue(this._prefix(key), defaultValue));
        },
        write : function(key, value) {
            return GM_setValue(this._prefix(key), this.serialize(value));
        },
        delete : function(key) {
            return GM_deleteValue(this._prefix(key));
        },
        readKeys : function() {
            return GM_listValues();
        },
        // /GM Storage API

        getAll : function() {
            const keys = this._listKeys();
            let obj    = {};

            for (let i = 0, len = keys.length; i < len; i++) {
                obj[keys[i]] = this.read(keys[i]);
            }
            return obj;
        },
        getKeys : function() {
            return this._listKeys();
        },
        getPrefix : function() {
            return this.options.prefix;
        },

        empty : function() {
            const keys = this._listKeys();

            for (let i = 0, len = keys.lenght; i < len; i++) {
                this.delete(keys[i]);
            }
        },
        has : function(key) {
            return this.get(key) !== null;
        },
        forEach : function(callbackFunc) {
            const allContent = this.getAll();

            for (let prop in allContent) {
                callbackFunc(prop, allContent[prop]);
            }
        },
        unserialize : function(value) {
            if (this._isJson(value)) {
                return JSON.parse(value);
            }
            return value;
        },
        serialize : function(value) {
            if (this._isJson(value)) {
                return JSON.stringify(value);
            }
            return value;
        },
        _listKeys : function(usePrefix = false) {
            const prefixed = this.readKeys();
            let unprefixed = [];

            if (usePrefix) {
                return prefixed;
            } else {
                for (let i = 0, len = prefixed.length; i < len; i++) {
                    unprefixed[i] = this._unprefix(prefixed[i]);
                }
                return unprefixed;
            }
        },
        _prefix : function(key) {
            return this.options.prefix + key;
        },
        _unprefix : function(key) {
            return key.substring(this.options.prefix.length);
        },
        _isJson : function(item) {
            try {
                JSON.parse(item);
            } catch (e) {
                return false;
            }
            return true;
        },
        _isObject : function(a) {
            return (!!a) && (a.constructor === Object);
        },
        _isArray : function(a) {
            return (!!a) && (a.constructor === Array);
        }
    };