File: src/js/node/adapters/UnicacheMemory.js

"use strict";

module.exports = function(UNICACHE) {
    var PROTO = 'prototype', _ = UNICACHE._;

    var MemoryCache = UNICACHE.MemoryCache = function() {
        this._cache = {};
    };

    // extend UNICACHE.Cache class
    MemoryCache[PROTO] = Object.create(UNICACHE.Cache[PROTO]);

    MemoryCache.isSupported = function() {
        return true;
    };

    MemoryCache[PROTO]._cache = null;

    MemoryCache[PROTO].dispose = function() {
        this._cache = null;
        return UNICACHE.Cache[PROTO].dispose.call(this);
    };

    MemoryCache[PROTO].supportsSync = function() {
        // can read/write/etc using sync operations as well
        return true;
    };

    MemoryCache[PROTO].put = function(key, data, ttl, cb) {
        this._cache[this.prefix + key] = [_.time() + ttl, data];
        if ('function' === typeof cb) cb(null, true);
    };

    MemoryCache[PROTO].get = function(key, cb) {
        var ret;
        if (!_.isset(this._cache, this.prefix + key, true))
        {
            ret = false;
        }
        else
        {
            var data = this._cache[this.prefix + key];

            if (!data || (_.time() > data[0]))
            {
                delete this._cache[this.prefix + key];
                ret = false;
            }
            else
            {
                ret = data[1];
            }
        }
        if ('function' === typeof cb)
        {
            cb(null, ret);
        }
        else
        {
            return ret;
        }
    };

    MemoryCache[PROTO].remove = function(key, cb) {
        var ret;
        if (!_.isset(this._cache, this.prefix + key))
        {
            ret = false;
        }
        else
        {
            delete this._cache[this.prefix + key];
            ret = true;
        }
        if ('function' === typeof cb)
        {
            cb(null, ret);
        }
        else
        {
            return ret;
        }
    };

    MemoryCache[PROTO].clear = function(cb) {
        if (!this.prefix.length)
        {
            this._cache = {};
        }
        else
        {
            for (key in this._cache)
            {
                if (!_.isset(this._cache, key)) continue;
                if (0 === key.indexOf(this.prefix))
                {
                    delete this._cache[key];
                }
            }
        }
        if ('function' === typeof cb)
        {
            cb(null, true);
        }
        else
        {
            return true;
        }
    };

    MemoryCache[PROTO].gc = function(maxlifetime, cb) {
        maxlifetime = +maxlifetime;
        var currenttime = _.time(),
            pl = this.prefix.length, data;
        for (key in this._cache)
        {
            if (!_.isset(this._cache, key)) continue;
            if (!pl || (0 === key.indexOf(this.prefix)))
            {
                data = this._cache[key];
                if (data[0] < currenttime-maxlifetime)
                    delete this._cache[key];
            }
        }
        if ('function' === typeof cb)
        {
            cb(null, true);
        }
        else
        {
            return true;
        }
    };

    return MemoryCache;
};