identifier.rs

// SPDX-License-Identifier: MIT
// Copyright ${YEAR} IROX Contributors
//

//!
//! An Identifier represents a way to uniquely identify an item, whether as a [`String`], [`u64`],
//! or [`UUID`].
//!

extern crate alloc;
use crate::format;
use crate::murmur3::murmur3_128;
use crate::uuid::UUID;
use alloc::string::{String, ToString};
use core::fmt::{Display, Formatter};

///
/// Represents a way to uniquely identify an item.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub enum Identifier {
    Integer(u64),
    String(String),
    UUID(UUID),
}

impl Identifier {
    /// Represents this identifier as an [`u64`] type
    #[must_use]
    pub fn as_integer(&self) -> Identifier {
        match self {
            Identifier::Integer(i) => Identifier::Integer(*i),
            Identifier::String(s) => {
                let hash = murmur3_128(s.as_bytes());
                Identifier::Integer(hash as u64)
            }
            Identifier::UUID(u) => {
                let inner: u128 = u.into();
                Identifier::Integer(inner as u64)
            }
        }
    }

    /// Represents this identifier as a [`String`] type
    #[must_use]
    pub fn as_string(&self) -> Identifier {
        match self {
            Identifier::Integer(i) => Identifier::String(format!("{i}")),
            Identifier::String(s) => Identifier::String(s.to_string()),
            Identifier::UUID(u) => Identifier::String(format!("{u}")),
        }
    }

    /// Represents this identifier as a [`UUID`] type
    #[must_use]
    pub fn as_uuid(&self) -> Identifier {
        match self {
            Identifier::Integer(i) => {
                let inner: u128 = *i as u128;
                Identifier::UUID(inner.into())
            }
            Identifier::String(s) => {
                let inner: u128 = murmur3_128(s);
                Identifier::UUID(inner.into())
            }
            Identifier::UUID(u) => Identifier::UUID(*u),
        }
    }
}

impl Display for Identifier {
    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
        match self {
            Identifier::Integer(i) => f.write_fmt(format_args!("{i}")),
            Identifier::String(s) => f.write_fmt(format_args!("{s}")),
            Identifier::UUID(u) => f.write_fmt(format_args!("{u}")),
        }
    }
}

impl From<u64> for Identifier {
    fn from(value: u64) -> Self {
        Identifier::Integer(value)
    }
}

impl From<&u64> for Identifier {
    fn from(value: &u64) -> Self {
        Identifier::Integer(*value)
    }
}

impl From<String> for Identifier {
    fn from(value: String) -> Self {
        Identifier::String(value)
    }
}

impl From<&str> for Identifier {
    fn from(value: &str) -> Self {
        Identifier::String(value.to_string())
    }
}

impl From<UUID> for Identifier {
    fn from(value: UUID) -> Self {
        Identifier::UUID(value)
    }
}

impl From<&UUID> for Identifier {
    fn from(value: &UUID) -> Self {
        Identifier::UUID(*value)
    }
}