use std::fmt;
use std::str::FromStr;

use crate::types::{ProtocolVersion, RequiredVersion};
use crate::utils::{quote, tag, unquote};
use crate::Error;

#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
/// KeyFormat specifies, how the key is represented in the resource identified by the URI
pub enum KeyFormat {
    /// The key is a single packed array of 16 octets in binary format.
    Identity,
}

impl Default for KeyFormat {
    fn default() -> Self {
        Self::Identity
    }
}

impl FromStr for KeyFormat {
    type Err = Error;

    fn from_str(input: &str) -> Result<Self, Self::Err> {
        tag(&unquote(input), "identity")?; // currently only KeyFormat::Identity exists!

        Ok(Self::Identity)
    }
}

impl fmt::Display for KeyFormat {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}", quote("identity"))
    }
}

impl RequiredVersion for KeyFormat {
    fn required_version(&self) -> ProtocolVersion {
        ProtocolVersion::V5
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_display() {
        assert_eq!(KeyFormat::Identity.to_string(), quote("identity"));
    }

    #[test]
    fn test_parser() {
        assert_eq!(KeyFormat::Identity, quote("identity").parse().unwrap());

        assert_eq!(KeyFormat::Identity, "identity".parse().unwrap());

        assert!("garbage".parse::<KeyFormat>().is_err());
    }

    #[test]
    fn test_required_version() {
        assert_eq!(KeyFormat::Identity.required_version(), ProtocolVersion::V5)
    }

    #[test]
    fn test_default() {
        assert_eq!(KeyFormat::Identity, KeyFormat::default());
    }
}