use crate::ser::Serializer;
use crate::Error;
use serde::ser::Impossible;
use serde::{serde_if_integer128, Serialize, Serializer as _};
use std::borrow::Cow;
use std::io::Write;
use std::ops::Deref;
pub(crate) struct KeySerializer<'a, W> {
pub(crate) ser: &'a mut Serializer<W>,
}
impl<'a, W> KeySerializer<'a, W>
where
W: Write,
{
fn serialize_int<I>(self, v: I) -> Result<(), Error>
where
I: itoa::Integer,
{
let mut buffer = itoa::Buffer::new();
let v = buffer.format(v);
self.serialize_str(v)
}
fn serialize_shared_property(&mut self, v: MaybeStatic<'_, str>) -> Result<bool, Error> {
let shared_properties = match &mut self.ser.shared_properties {
Some(shared_properties) => shared_properties,
None => return Ok(false),
};
match shared_properties.get(&v) {
Some(backref) => {
if backref <= 63 {
self.ser
.writer
.write_all(&[0x40 + backref as u8])
.map_err(Error::io)?;
} else {
let buf = [0x30 | (backref >> 8) as u8, backref as u8];
self.ser.writer.write_all(&buf).map_err(Error::io)?;
}
Ok(true)
}
None => {
let cow = match v {
MaybeStatic::Static(v) => Cow::Borrowed(v),
MaybeStatic::Nonstatic(v) => Cow::Owned(v.to_string()),
};
shared_properties.intern(cow);
Ok(false)
}
}
}
pub(crate) fn serialize_maybe_static_str(
&mut self,
v: MaybeStatic<'_, str>,
) -> Result<(), Error> {
if v.is_empty() {
return self.ser.writer.write_all(&[0x20]).map_err(Error::io);
}
if self.serialize_shared_property(v)? {
return Ok(());
}
if v.len() <= 64 && v.is_ascii() {
self.ser
.writer
.write_all(&[0x80 + v.len() as u8 - 1])
.map_err(Error::io)?;
self.ser.writer.write_all(v.as_bytes()).map_err(Error::io)?;
} else if v.len() < 57 {
self.ser
.writer
.write_all(&[0xc0 + v.len() as u8 - 2])
.map_err(Error::io)?;
self.ser.writer.write_all(v.as_bytes()).map_err(Error::io)?;
} else {
self.ser.writer.write_all(&[0x34]).map_err(Error::io)?;
self.ser.writer.write_all(v.as_bytes()).map_err(Error::io)?;
self.ser.writer.write_all(&[0xfc]).map_err(Error::io)?;
}
Ok(())
}
}
impl<'a, W> serde::Serializer for KeySerializer<'a, W>
where
W: Write,
{
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, _v: bool) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_i8(self, v: i8) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
fn serialize_i16(self, v: i16) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
fn serialize_i32(self, v: i32) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
fn serialize_i64(self, v: i64) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
serde_if_integer128! {
fn serialize_i128(self, v: i128) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
}
fn serialize_u8(self, v: u8) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
fn serialize_u16(self, v: u16) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
fn serialize_u32(self, v: u32) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
fn serialize_u64(self, v: u64) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
serde_if_integer128! {
fn serialize_u128(self, v: u128) -> Result<Self::Ok, Self::Error> {
self.serialize_int(v)
}
}
fn serialize_f32(self, _v: f32) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_f64(self, _v: f64) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_char(self, v: char) -> Result<Self::Ok, Self::Error> {
self.serialize_str(v.encode_utf8(&mut [0; 4]))
}
fn serialize_str(mut self, v: &str) -> Result<Self::Ok, Self::Error> {
self.serialize_maybe_static_str(MaybeStatic::Nonstatic(v))
}
fn serialize_bytes(self, _v: &[u8]) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_some<T>(self, _value: &T) -> Result<Self::Ok, Self::Error>
where
T: Serialize + ?Sized,
{
Err(Error::key_must_be_a_string())
}
fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_unit_variant(
mut self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
) -> Result<Self::Ok, Self::Error> {
self.serialize_maybe_static_str(MaybeStatic::Static(variant))
}
fn serialize_newtype_struct<T>(
self,
_name: &'static str,
value: &T,
) -> Result<Self::Ok, Self::Error>
where
T: Serialize + ?Sized,
{
value.serialize(self)
}
fn serialize_newtype_variant<T>(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_value: &T,
) -> Result<Self::Ok, Self::Error>
where
T: Serialize + ?Sized,
{
Err(Error::key_must_be_a_string())
}
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_tuple_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleStruct, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeStruct, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant, Self::Error> {
Err(Error::key_must_be_a_string())
}
fn is_human_readable(&self) -> bool {
true
}
}
pub(crate) enum MaybeStatic<'a, T>
where
T: ?Sized + 'static,
{
Static(&'static T),
Nonstatic(&'a T),
}
impl<T> Copy for MaybeStatic<'_, T> where T: ?Sized {}
impl<T> Clone for MaybeStatic<'_, T>
where
T: ?Sized,
{
fn clone(&self) -> Self {
*self
}
}
impl<'a, T> Deref for MaybeStatic<'a, T>
where
T: ?Sized,
{
type Target = T;
fn deref(&self) -> &Self::Target {
match self {
MaybeStatic::Static(v) => v,
MaybeStatic::Nonstatic(v) => v,
}
}
}