glucose 0.1.3

use serde::{Serialize, Serializer, Deserialize, Deserializer};
use crate::{Vector, Matrix};
use serde::ser::SerializeSeq;
use serde::de::{Visitor, SeqAccess, Error};
use std::fmt::Formatter;
use std::marker::PhantomData;
use crate::numeric::num::Num;

impl<T: Num + Serialize, const N: usize> Serialize for Vector<T, { N }> {
    fn serialize<S>(&self, serializer: S) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error> where
        S: Serializer {
        let mut seq = serializer.serialize_seq(Some(N))?;
        for e in &self.data {
            seq.serialize_element(e)?;
        }
        seq.end()
    }
}


struct VectorVisitor<T, const N: usize> {
    marker: PhantomData<T>
}

impl<T, const N: usize> VectorVisitor<T, { N }> {
    pub fn new() -> Self {
        Self {
            marker: PhantomData
        }
    }
}
impl<'de, T: Num + Default + Deserialize<'de> + Copy, const N: usize> Deserialize<'de> for Vector<T, { N }> {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where
        D: Deserializer<'de> {
        deserializer.deserialize_seq(VectorVisitor::new())
    }
}

impl<'de, T: Num + Default + Deserialize<'de> + Copy, const N: usize> Visitor<'de> for VectorVisitor<T, { N }> {
    type Value = Vector<T, { N }>;

    fn expecting(&self, formatter: &mut Formatter) -> std::fmt::Result {
        formatter.write_str("vector")
    }

    fn visit_seq<V>(self, mut seq: V) -> Result<Vector<T, { N }>, V::Error> where V: SeqAccess<'de> {
        let mut vec = Vector::default();
        for i in 0..N {
            vec[i] = seq.next_element()?.unwrap();
        }
        Ok(vec)
    }
}


#[cfg(test)]
mod serde_tests {
    use crate::Vector;
    use serde::{Serialize, Deserialize};
    use serde_test::{assert_tokens, Token};

    #[test]
    fn vec_serialize_deserialize() {
        let vec = Vector::new([0.1, 0.4, -2.0]);
        assert_tokens(&vec, &[
            Token::Seq {len: Some(3)},
            Token::F64(0.1),
            Token::F64(0.4),
            Token::F64(-2.0),
        ]);
    }
}