use std::{borrow::Cow, mem};
use form_urlencoded::{Serializer as UrlEncodedSerializer, Target as UrlEncodedTarget};
use serde::ser;
use crate::ser::{key::KeySink, part::PartSerializer, value::ValueSink, Error};
pub struct PairSerializer<'input, 'target, Target: UrlEncodedTarget> {
urlencoder: &'target mut UrlEncodedSerializer<'input, Target>,
state: PairState,
}
impl<'input, 'target, Target> PairSerializer<'input, 'target, Target>
where
Target: 'target + UrlEncodedTarget,
{
pub fn new(urlencoder: &'target mut UrlEncodedSerializer<'input, Target>) -> Self {
PairSerializer { urlencoder, state: PairState::WaitingForKey }
}
}
impl<'input, 'target, Target> ser::Serializer for PairSerializer<'input, 'target, Target>
where
Target: 'target + UrlEncodedTarget,
{
type Ok = ();
type Error = Error;
type SerializeSeq = ser::Impossible<(), Error>;
type SerializeTuple = Self;
type SerializeTupleStruct = ser::Impossible<(), Error>;
type SerializeTupleVariant = ser::Impossible<(), Error>;
type SerializeMap = ser::Impossible<(), Error>;
type SerializeStruct = ser::Impossible<(), Error>;
type SerializeStructVariant = ser::Impossible<(), Error>;
fn serialize_bool(self, _v: bool) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_i8(self, _v: i8) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_i16(self, _v: i16) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_i32(self, _v: i32) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_i64(self, _v: i64) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_u8(self, _v: u8) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_u16(self, _v: u16) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_u32(self, _v: u32) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_u64(self, _v: u64) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_f32(self, _v: f32) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_f64(self, _v: f64) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_char(self, _v: char) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_str(self, _value: &str) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_bytes(self, _value: &[u8]) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_unit(self) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_unit_struct(self, _name: &'static str) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_unit_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_newtype_struct<T: ?Sized + ser::Serialize>(
self,
_name: &'static str,
value: &T,
) -> Result<(), Error> {
value.serialize(self)
}
fn serialize_newtype_variant<T: ?Sized + ser::Serialize>(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_value: &T,
) -> Result<(), Error> {
Err(Error::unsupported_pair())
}
fn serialize_none(self) -> Result<(), Error> {
Ok(())
}
fn serialize_some<T: ?Sized + ser::Serialize>(self, value: &T) -> Result<(), Error> {
value.serialize(self)
}
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Error> {
Err(Error::unsupported_pair())
}
fn serialize_tuple(self, len: usize) -> Result<Self, Error> {
if len == 2 {
Ok(self)
} else {
Err(Error::unsupported_pair())
}
}
fn serialize_tuple_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleStruct, Error> {
Err(Error::unsupported_pair())
}
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant, Error> {
Err(Error::unsupported_pair())
}
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Error> {
Err(Error::unsupported_pair())
}
fn serialize_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeStruct, Error> {
Err(Error::unsupported_pair())
}
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant, Error> {
Err(Error::unsupported_pair())
}
}
impl<'input, 'target, Target> ser::SerializeTuple for PairSerializer<'input, 'target, Target>
where
Target: 'target + UrlEncodedTarget,
{
type Ok = ();
type Error = Error;
fn serialize_element<T: ?Sized + ser::Serialize>(&mut self, value: &T) -> Result<(), Error> {
match mem::replace(&mut self.state, PairState::Done) {
PairState::WaitingForKey => {
let key_sink = KeySink::new(|key| Ok(key.into()));
let key_serializer = PartSerializer::new(key_sink);
self.state = PairState::WaitingForValue { key: value.serialize(key_serializer)? };
Ok(())
}
PairState::WaitingForValue { key } => {
let result = {
let value_sink = ValueSink::new(self.urlencoder, &key);
let value_serializer = PartSerializer::new(value_sink);
value.serialize(value_serializer)
};
if result.is_ok() {
self.state = PairState::Done;
} else {
self.state = PairState::WaitingForValue { key };
}
result
}
PairState::Done => Err(Error::done()),
}
}
fn end(self) -> Result<(), Error> {
if let PairState::Done = self.state {
Ok(())
} else {
Err(Error::not_done())
}
}
}
enum PairState {
WaitingForKey,
WaitingForValue { key: Cow<'static, str> },
Done,
}