var hashes = new (function () {

    var _this = this;

    var _SEPERATOR_KEY_VALUE = ":";

    var _SEPERATOR_PAIR = "|";

    var _OLD_HASHES = {};

    /**
     * Add Hash event.
     *
     * @param hash
     * @param callback
     */
    this.addHashEvent = function(hash, callback) {
        window.hashes = window.hashes || {};
        window.hashes[hash] = callback;
    };

    /**
     * When hash is change we fire this method, or you can fire manually.
     * hash must be on the following patter: key:value;key1:value, it will transform to:
     * ['key:value', 'ke1:value'] for later to be dispatch to window.hashes.key => value
     * and window.hashes.key1 = value1;
     */
    this.fireHashOnChange = function () {
        let hashes = getMapOfHash();
        for(let hash in hashes) {

            let value = hashes[hash];
            if (!window.hashes[hash]) {
                continue;
            }

            if (_this._OLD_HASHES && _this._OLD_HASHES[hash] && _this._OLD_HASHES[hash] === value) {
                continue;
            }


            let callback = window.hashes[hash];
            _this._OLD_HASHES[hash] = value;
            callback.call(_this, value);
        }

    };

    /**
     * Add/Change hash on url but maintain the actual hash already added.
     * @param hashKey
     * @param hashValue
     */
    this.addHash = function(hashKey, hashValue) {
        let hashes = getMapOfHash();
        hashes[hashKey] = hashValue;
        let fullHashes = [];
        for(let hash in hashes) {
            fullHashes.push(hash+_SEPERATOR_KEY_VALUE+hashes[hash]);
        }
        window.location.hash = fullHashes.join(_SEPERATOR_PAIR);
    }

    /**
     * Remove Hash from hashes.
     * @param hashKey
     * @param hashValue
     */
    this.removeHash = function(hashKey) {
        let hashes = getMapOfHash();
        let fullHashes = [];
        for(let hash in hashes) {
            if (hash !== hashKey) {
                fullHashes.push(hash+_SEPERATOR_KEY_VALUE+hashes[hash]);
            }
        }
        window.location.hash = fullHashes.join(_SEPERATOR_PAIR);
    }

    /**
     * Hash on Change.
     */
    let hashOnChange = function () {
        window.addEventListener("hashchange", _this.fireHashOnChange, false);
    };

    /**
     * Get all hashes from url
     */
    let getMapOfHash = function () {
        let hashes = location.hash.toString();
        let map = {};
        if (!hashes) {
            return map;
        }
        if (hashes.indexOf(";") >= -1) {
            hashes = hashes.split(_SEPERATOR_PAIR);
        } else {
            hashes = [hashes];
        }

        for(let hash of hashes) {
            hash = hash.replace("#", "");
            let parts = hash.split(_SEPERATOR_KEY_VALUE);
            map[parts[0]] = parts[1];
        }
        return map;
    }

    hashOnChange();

    window.addEventListener("hashchange", function () {
        _this.fireHashOnChange.call(_this);
    }, false);
})();