//  Copyright 2019 The Tari Project
//
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//  following disclaimer in the documentation and/or other materials provided with the distribution.
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use rand::{RngCore, rngs::OsRng};

/// Represents a local peer id. This number is meaningless outside of this node.
pub type PeerId = u64;

/// Generates a random peer key that is guaranteed to be positive '< u64::MAX'.
pub fn generate_peer_key() -> PeerId {
    OsRng.next_u64().saturating_sub(1)
}

/// Generates a random peer key that is guaranteed to be positive '< i64::MAX'.
pub fn generate_peer_id_as_i64() -> i64 {
    i64::try_from(generate_peer_key() % u64::try_from(i64::MAX).expect("infallible")).expect("infallible")
}

/// Converts a positive i64 to a PeerId. This is infallible as the value is guaranteed to be positive.
pub fn peer_id_from_i64(value: i64) -> PeerId {
    let value = if value == i64::MIN { i64::MAX } else { value.abs() };
    u64::try_from(value).expect("infallible")
}
