//! Newtype wrappers for primitive data types with semantic meaning.
#![allow(clippy::unit_arg)]
use crate::serialization::{
    ReadZcashExt, SerializationError, WriteZcashExt, ZcashDeserialize, ZcashSerialize,
};
use std::{
    fmt,
    io::{self, Read},
};

/// A sequence of message authentication tags ...
///
/// binding h_sig to each a_sk of the JoinSplit description, computed as
/// described in § 4.10 ‘Non-malleability (Sprout)’ on p. 37
#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
#[cfg_attr(test, derive(proptest_derive::Arbitrary))]
pub struct MAC([u8; 32]);

impl ZcashDeserialize for MAC {
    fn zcash_deserialize<R: Read>(mut reader: R) -> Result<Self, SerializationError> {
        let bytes = reader.read_32_bytes()?;

        Ok(Self(bytes))
    }
}

impl ZcashSerialize for MAC {
    fn zcash_serialize<W: io::Write>(&self, mut writer: W) -> Result<(), io::Error> {
        writer.write_all(&self.0[..])
    }
}
/// An encoding of a Bitcoin script.
#[derive(Clone, Eq, PartialEq, Serialize, Deserialize)]
#[cfg_attr(test, derive(proptest_derive::Arbitrary))]
pub struct Script(pub Vec<u8>);

impl fmt::Debug for Script {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.debug_tuple("Script")
            .field(&hex::encode(&self.0))
            .finish()
    }
}

impl ZcashSerialize for Script {
    fn zcash_serialize<W: io::Write>(&self, mut writer: W) -> Result<(), io::Error> {
        writer.write_compactsize(self.0.len() as u64)?;
        writer.write_all(&self.0[..])?;
        Ok(())
    }
}

impl ZcashDeserialize for Script {
    fn zcash_deserialize<R: io::Read>(mut reader: R) -> Result<Self, SerializationError> {
        // XXX what is the max length of a script?
        let len = reader.read_compactsize()?;
        let mut bytes = Vec::new();
        reader.take(len).read_to_end(&mut bytes)?;
        Ok(Script(bytes))
    }
}

#[cfg(test)]
mod proptests {
    use std::io::Cursor;

    use proptest::prelude::*;

    use super::*;
    use crate::serialization::{ZcashDeserialize, ZcashSerialize};

    proptest! {
        #[test]
        fn script_roundtrip(script in any::<Script>()) {
            let mut bytes = Cursor::new(Vec::new());
            script.zcash_serialize(&mut bytes)?;

            bytes.set_position(0);
            let other_script = Script::zcash_deserialize(&mut bytes)?;

            prop_assert_eq![script, other_script];
        }
    }
}