use core::fmt;

use num_enum::{IntoPrimitive, TryFromPrimitive};

/// Message Identifier used in the communication protocol. This is specified by Viessmann
/// and UNACKED is rarely to never used.
#[repr(u8)]
#[derive(Debug, TryFromPrimitive, IntoPrimitive, Clone, Copy, PartialEq, Eq)]
pub enum MessageIdentifier {
    Request = 0x00,
    Response = 0x01,
    Unacked = 0x02,
    CommError = 0x03,
}

impl fmt::Display for MessageIdentifier {
    #[inline]
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match *self {
            Self::Request => write!(f, "Request"),
            Self::Response => write!(f, "Response"),
            Self::Unacked => write!(f, "Unacked"),
            Self::CommError => write!(f, "CommError"),
        }
    }
}

/// Function Code used in the communication protocol.
/// 
/// This is specified by Viessmann and Read and Write are usually used for simpler values, 
/// RPC can maybe be used for more complex things, but this is currently unclear
#[repr(u8)]
#[derive(Debug, TryFromPrimitive, IntoPrimitive, Clone, Copy, PartialEq, Eq)]
pub enum FunctionCode {
    VirtualREAD = 0x01,
    VirtualWRITE = 0x02,
    RemoteProcedureCall = 0x07,
}

impl fmt::Display for FunctionCode {
    #[inline]
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match *self {
            Self::VirtualREAD => write!(f, "VirtualREAD"),
            Self::VirtualWRITE => write!(f, "VirtualWRITE"),
            Self::RemoteProcedureCall => write!(f, "RemoteProcedureCall"),
        }
    }
}

/// Response code used in the communication protocol. This is specified by Viessmann
#[repr(u8)]
#[derive(Debug, TryFromPrimitive)]
pub enum ResponseCode {
    Ack = 0x06,
    Nack = 0x15,
    Enq = 0x05,
}