import util from './util';

let localStore = {
    _storage: util.safeStorage('local'),
    get(key)
    {
        let val = this._storage.getItem(key);

        try {
            val = JSON.parse(val);
        /* eslint-disable no-empty */
        } catch (e) {}

        return val;
    },
    set(key, val)
    {
        if (util.isObj(val)) val = JSON.stringify(val);

        this._storage.setItem(key, val);

        return this;
    },
    remove(key)
    {
        this._storage.removeItem(key);

        return this;
    }
};

export default class Storage extends util.Emitter
{
    constructor(name)
    {
        super();
        this._name = name;
        this._val = localStore.get(name);
        if (!this._val || !util.isObj(this._val)) this._val = {};
    }
    save()
    {
        localStore.set(this._name, this._val);

        return this;
    }
    get(key)
    {
        if (util.isUndef(key)) return this._val;

        return this._val[key];
    }
    set(key, val)
    {
        let kv;

        if (util.isObj(key))
        {
            kv = key;
        } else
        {
            kv = {};
            kv[key] = val;
        }

        util.each(kv, (val, key) =>
        {
            let preVal = this._val[key];
            this._val[key] = val;
            if (preVal !== val) this.emit('change', key, val);
        });

        return this.save();
    }
}