BI.Cache = {
    _prefix: "bi",
    setUsername: function (username) {
        localStorage.setItem(BI.Cache._prefix + ".username", (username + "" || "").toUpperCase());
    },
    getUsername: function () {
        return localStorage.getItem(BI.Cache._prefix + ".username") || "";
    },
    _getKeyPrefix: function () {
        return BI.Cache.getUsername() + "." + BI.Cache._prefix + ".";
    },
    _generateKey: function (key) {
        return BI.Cache._getKeyPrefix() + (key || "");
    },
    getItem: function (key) {
        return localStorage.getItem(BI.Cache._generateKey(key));
    },
    setItem: function (key, value) {
        localStorage.setItem(BI.Cache._generateKey(key), value);
    },
    removeItem: function (key) {
        localStorage.removeItem(BI.Cache._generateKey(key));
    },
    clear: function () {
        for (var i = localStorage.length; i >= 0; i--) {
            var key = localStorage.key(i);
            if (key) {
                if (key.indexOf(BI.Cache._getKeyPrefix()) === 0) {
                    localStorage.removeItem(key);
                }
            }
        }
    },
    keys: function () {
        var result = [];
        for (var i = localStorage.length; i >= 0; i--) {
            var key = localStorage.key(i);
            if (key) {
                var prefix = BI.Cache._getKeyPrefix();
                if (key.indexOf(prefix) === 0) {
                    result[result.length] = key.substring(prefix.length);
                }
            }
        }
        return result;
    },

    addCookie: function (name, value, path, expiresHours) {
        var cookieString = name + "=" + escape(value);
        // 判断是否设置过期时间
        if (expiresHours && expiresHours > 0) {
            var date = new Date();
            // expires是标准GMT格式时间，应该使用时间戳作为起始时间
            date.setTime(date.getTime() + expiresHours * 3600 * 1000);
            cookieString = cookieString + "; expires=" + date.toUTCString();
        }
        if (path) {
            cookieString = cookieString + "; path=" + path;
        }
        document.cookie = cookieString;
    },
    getCookie: function (name) {
        var arr, reg = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
        if (arr = document.cookie.match(reg)) {return unescape(arr[2]);}
        return null;
    },
    deleteCookie: function (name, path) {
        var date = new Date();
        date.setTime(date.getTime() - 10000);
        var cookieString = name + "=v; expires=" + date.toUTCString();
        if (path) {
            cookieString = cookieString + "; path=" + path;
        }
        document.cookie = cookieString;
    }
};