statime-wire 0.1.1

use crate::{Error, common::Timestamp};

/// Follow up message for a sync message.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct FollowUpMessage {
    /// Precise time the matching sync message was transmitted.
    pub precise_origin_timestamp: Timestamp,
}

impl FollowUpMessage {
    pub(crate) fn content_size(&self) -> usize {
        10
    }

    pub(crate) fn serialize_content(&self, buffer: &mut [u8]) -> Result<(), Error> {
        self.precise_origin_timestamp
            .serialize(buffer.get_mut(0..10).ok_or(Error::BufferTooShort)?)?;

        Ok(())
    }

    pub(crate) fn deserialize_content(buffer: &[u8]) -> Result<Self, Error> {
        let slice = buffer.get(0..10).ok_or(Error::BufferTooShort)?;
        let precise_origin_timestamp = Timestamp::deserialize(slice)?;

        Ok(Self {
            precise_origin_timestamp,
        })
    }
}

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

    #[test]
    fn timestamp_wireformat() {
        let representations = [
            (
                [0x00, 0x00, 0x45, 0xb1, 0x11, 0x5a, 0x0a, 0x64, 0xfa, 0xb0],
                FollowUpMessage {
                    precise_origin_timestamp: Timestamp::new(1_169_232_218, 174_389_936).unwrap(),
                },
            ),
            (
                [0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x01u8],
                FollowUpMessage {
                    precise_origin_timestamp: Timestamp::new(0x0000_0000_0002, 0x0000_0001)
                        .unwrap(),
                },
            ),
        ];

        for (byte_representation, object_representation) in representations {
            // Test the serialization output
            let mut serialization_buffer = [0; 10];
            object_representation
                .serialize_content(&mut serialization_buffer)
                .unwrap();
            assert_eq!(serialization_buffer, byte_representation);

            // Test the deserialization output
            let deserialized_data =
                FollowUpMessage::deserialize_content(&byte_representation).unwrap();
            assert_eq!(deserialized_data, object_representation);
        }
    }
}