fastnbt 2.5.0

use std::io::Write;

use serde::{ser::Impossible, Serializer};

use crate::error::Error;

pub(crate) struct NameSerializer<W: Write> {
    pub(crate) name: W,
}

fn name_must_be_stringy(ty: &str) -> Error {
    Error::bespoke(format!("field must be string-like, found {ty}"))
}

/// NameSerializer is all about serializing the name of a field. It does not
/// write the length or the tag. We typically need to write this to a different
/// buffer than the main one we're writing to, because we need to write out the
/// field in tag, name, value order. In order the write the tag we need to know
/// what value we're serializing, which we can only do when we serialize the
/// value. So we save the name start serializing the value, which serializes the
/// tag, then the saved name, then the value.
impl<W: Write> Serializer for &mut NameSerializer<W> {
    type Ok = ();
    type Error = Error;
    type SerializeSeq = Impossible<(), Error>;
    type SerializeTuple = Impossible<(), Error>;
    type SerializeTupleStruct = Impossible<(), Error>;
    type SerializeTupleVariant = Impossible<(), Error>;
    type SerializeMap = Impossible<(), Error>;
    type SerializeStruct = Impossible<(), Error>;
    type SerializeStructVariant = Impossible<(), Error>;

    fn serialize_bool(self, _: bool) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("bool"))
    }

    fn serialize_i8(self, _: i8) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("i8"))
    }

    fn serialize_i16(self, _: i16) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("i16"))
    }

    fn serialize_i32(self, _: i32) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("i32"))
    }

    fn serialize_i64(self, _: i64) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("i64"))
    }

    fn serialize_u8(self, _: u8) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("u8"))
    }

    fn serialize_u16(self, _: u16) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("u16"))
    }

    fn serialize_u32(self, _: u32) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("u32"))
    }

    fn serialize_u64(self, _: u64) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("u64"))
    }

    fn serialize_f32(self, _: f32) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("f32"))
    }

    fn serialize_f64(self, _: f64) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("f64"))
    }

    fn serialize_char(self, c: char) -> Result<Self::Ok, Self::Error> {
        self.name.write_all(&cesu8::to_java_cesu8(&c.to_string()))?;
        Ok(())
    }

    fn serialize_str(self, v: &str) -> Result<Self::Ok, Self::Error> {
        self.name.write_all(&cesu8::to_java_cesu8(v))?;
        Ok(())
    }

    fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok, Self::Error> {
        self.name.write_all(v)?;
        Ok(())
    }

    fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("none"))
    }

    fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
    where
        T: serde::Serialize,
    {
        Err(name_must_be_stringy("some"))
    }

    fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("unit"))
    }

    fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("unit_struct"))
    }

    fn serialize_unit_variant(
        self,
        _name: &'static str,
        _variant_index: u32,
        _variant: &'static str,
    ) -> Result<Self::Ok, Self::Error> {
        Err(name_must_be_stringy("unit_variant"))
    }

    fn serialize_newtype_struct<T: ?Sized>(
        self,
        _name: &'static str,
        _value: &T,
    ) -> Result<Self::Ok, Self::Error>
    where
        T: serde::Serialize,
    {
        Err(name_must_be_stringy("newtype_struct"))
    }

    fn serialize_newtype_variant<T: ?Sized>(
        self,
        _: &'static str,
        _: u32,
        _: &'static str,
        _: &T,
    ) -> Result<Self::Ok, Self::Error>
    where
        T: serde::Serialize,
    {
        Err(name_must_be_stringy("newtype_variant"))
    }

    fn serialize_seq(self, _: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
        Err(name_must_be_stringy("seq"))
    }

    fn serialize_tuple(self, _: usize) -> Result<Self::SerializeTuple, Self::Error> {
        Err(name_must_be_stringy("tuple"))
    }

    fn serialize_tuple_struct(
        self,
        _: &'static str,
        _: usize,
    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
        Err(name_must_be_stringy("tuple_struct"))
    }

    fn serialize_tuple_variant(
        self,
        _: &'static str,
        _: u32,
        _: &'static str,
        _: usize,
    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
        Err(name_must_be_stringy("tuple_variant"))
    }

    fn serialize_map(self, _: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
        Err(name_must_be_stringy("map"))
    }

    fn serialize_struct(
        self,
        _: &'static str,
        _: usize,
    ) -> Result<Self::SerializeStruct, Self::Error> {
        Err(name_must_be_stringy("struct"))
    }

    fn serialize_struct_variant(
        self,
        _: &'static str,
        _: u32,
        _: &'static str,
        _: usize,
    ) -> Result<Self::SerializeStructVariant, Self::Error> {
        Err(name_must_be_stringy("struct_variant"))
    }
}