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mod acl;
pub use self::acl::*;

mod watch;
pub use self::watch::*;

/// Statistics about a znode, similar to the UNIX `stat` structure.
///
/// # Time in ZooKeeper
/// The concept of time is tricky in distributed systems. ZooKeeper keeps track of time in a number
/// of ways.
///
/// - **zxid**: Every change to a ZooKeeper cluster receives a stamp in the form of a *zxid*
///   (ZooKeeper Transaction ID). This exposes the total ordering of all changes to ZooKeeper. Each
///   change will have a unique *zxid* -- if *zxid:a* is smaller than *zxid:b*, then the associated
///   change to *zxid:a* happened before *zxid:b*.
/// - **Version Numbers**: Every change to a znode will cause an increase to one of the version
///   numbers of that node.
/// - **Clock Time**: ZooKeeper does not use clock time to make decisions, but it uses it to put
///   timestamps into the `Stat` structure.
#[derive(Debug, PartialEq, Eq, Clone, Copy)]
pub struct Stat {
    /// The transaction ID that created the znode.
    pub czxid: i64,
    /// The last transaction that modified the znode.
    pub mzxid: i64,
    /// Milliseconds since epoch when the znode was created.
    pub ctime: i64,
    /// Milliseconds since epoch when the znode was last modified.
    pub mtime: i64,
    /// The number of changes to the data of the znode.
    pub version: i32,
    /// The number of changes to the children of the znode.
    pub cversion: i32,
    /// The number of changes to the ACL of the znode.
    pub aversion: i32,
    /// The session ID of the owner of this znode, if it is an ephemeral entry.
    pub ephemeral_owner: i64,
    /// The length of the data field of the znode.
    pub data_length: i32,
    /// The number of children this znode has.
    pub num_children: i32,
    /// The transaction ID that last modified the children of the znode.
    pub pzxid: i64,
}

/// CreateMode value determines how the znode is created on ZooKeeper.
#[repr(i32)]
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum CreateMode {
    /// The znode will not be automatically deleted upon client's disconnect.
    Persistent = 0,
    /// The znode will be deleted upon the client's disconnect.
    Ephemeral = 1,
    /// The name of the znode will be appended with a monotonically increasing number. The actual
    /// path name of a sequential node will be the given path plus a suffix `"i"` where *i* is the
    /// current sequential number of the node. The sequence number is always fixed length of 10
    /// digits, 0 padded. Once such a node is created, the sequential number will be incremented by
    /// one.
    PersistentSequential = 2,
    /// The znode will be deleted upon the client's disconnect, and its name will be appended with a
    /// monotonically increasing number.
    EphemeralSequential = 3,
    /// Container nodes are special purpose nodes useful for recipes such as leader, lock, etc. When
    /// the last child of a container is deleted, the container becomes a candidate to be deleted by
    /// the server at some point in the future. Given this property, you should be prepared to get
    /// `ZkError::NoNode` when creating children inside of this container node.
    Container = 4,
    //
    // 421
    // 000
    // ^----- is it a container?
    //  ^---- is it sequential?
    //   ^--- is it ephemeral?
}