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use serde::de::{
self,
value::{MapAccessDeserializer, MapDeserializer},
IntoDeserializer,
};
use std::{
array::IntoIter,
fmt::Display,
fs::File,
io::{BufReader, Cursor, Read, Seek},
iter::Peekable,
mem,
path::Path,
};
use crate::{
date::serde_impls::DATE_NEWTYPE_STRUCT_NAME,
error::{self, Error, ErrorKind, EventKind},
stream::{self, Event, OwnedEvent},
u64_to_usize,
uid::serde_impls::UID_NEWTYPE_STRUCT_NAME,
value::serde_impls::VALUE_NEWTYPE_STRUCT_NAME,
};
macro_rules! expect {
($next:expr, $kind:expr) => {
match $next {
Some(Ok(ref event)) if EventKind::of_event(event) != $kind => {
return Err(error::unexpected_event_type($kind, event))?;
}
Some(Ok(event)) => event,
Some(Err(err)) => return Err(err),
None => return Err(ErrorKind::UnexpectedEndOfEventStream.without_position()),
}
};
}
macro_rules! try_next {
($next:expr) => {
match $next {
Some(Ok(event)) => event,
Some(Err(err)) => return Err(err)?,
None => return Err(ErrorKind::UnexpectedEndOfEventStream.without_position())?,
}
};
}
#[doc(hidden)]
impl de::Error for Error {
fn custom<T: Display>(msg: T) -> Self {
ErrorKind::Serde(msg.to_string()).without_position()
}
}
enum OptionMode {
Root,
StructField,
Explicit,
}
/// A structure that deserializes plist event streams into Rust values.
pub struct Deserializer<I>
where
I: IntoIterator<Item = Result<OwnedEvent, Error>>,
{
events: Peekable<<I as IntoIterator>::IntoIter>,
option_mode: OptionMode,
in_plist_value: bool,
}
impl<I> Deserializer<I>
where
I: IntoIterator<Item = Result<OwnedEvent, Error>>,
{
pub fn new(iter: I) -> Deserializer<I> {
Deserializer {
events: iter.into_iter().peekable(),
option_mode: OptionMode::Root,
in_plist_value: false,
}
}
fn with_option_mode<T, F: FnOnce(&mut Deserializer<I>) -> Result<T, Error>>(
&mut self,
option_mode: OptionMode,
f: F,
) -> Result<T, Error> {
let prev_option_mode = mem::replace(&mut self.option_mode, option_mode);
let ret = f(&mut *self);
self.option_mode = prev_option_mode;
ret
}
fn enter_plist_value<T, F: FnOnce(&mut Deserializer<I>) -> Result<T, Error>>(
&mut self,
f: F,
) -> Result<T, Error> {
let prev = mem::replace(&mut self.in_plist_value, true);
let ret = f(&mut *self);
self.in_plist_value = prev;
ret
}
}
impl<'de, 'a, I> de::Deserializer<'de> for &'a mut Deserializer<I>
where
I: IntoIterator<Item = Result<OwnedEvent, Error>>,
{
type Error = Error;
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
match try_next!(self.events.next()) {
Event::StartArray(len) => {
let len = len.and_then(u64_to_usize);
let ret = visitor.visit_seq(MapAndSeqAccess::new(self, false, len))?;
expect!(self.events.next(), EventKind::EndCollection);
Ok(ret)
}
Event::StartDictionary(len) => {
let len = len.and_then(u64_to_usize);
let ret = visitor.visit_map(MapAndSeqAccess::new(self, false, len))?;
expect!(self.events.next(), EventKind::EndCollection);
Ok(ret)
}
event @ Event::EndCollection => Err(error::unexpected_event_type(
EventKind::ValueOrStartCollection,
&event,
)),
Event::Boolean(v) => visitor.visit_bool(v),
Event::Data(v) => visitor.visit_byte_buf(v.into_owned()),
Event::Date(v) if self.in_plist_value => {
visitor.visit_enum(MapAccessDeserializer::new(MapDeserializer::new(
IntoIter::new([(DATE_NEWTYPE_STRUCT_NAME, v.to_rfc3339())]),
)))
}
Event::Date(v) => visitor.visit_string(v.to_rfc3339()),
Event::Integer(v) => {
if let Some(v) = v.as_unsigned() {
visitor.visit_u64(v)
} else if let Some(v) = v.as_signed() {
visitor.visit_i64(v)
} else {
unreachable!()
}
}
Event::Real(v) => visitor.visit_f64(v),
Event::String(v) => visitor.visit_string(v.into_owned()),
Event::Uid(v) if self.in_plist_value => visitor.visit_enum(MapAccessDeserializer::new(
MapDeserializer::new(IntoIter::new([(UID_NEWTYPE_STRUCT_NAME, v.get())])),
)),
Event::Uid(v) => visitor.visit_u64(v.get()),
}
}
forward_to_deserialize_any! {
bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string
seq bytes byte_buf map unit_struct
tuple_struct tuple ignored_any identifier
}
fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
expect!(self.events.next(), EventKind::String);
visitor.visit_unit()
}
fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
match self.option_mode {
OptionMode::Root => {
if self.events.peek().is_none() {
visitor.visit_none::<Error>()
} else {
self.with_option_mode(OptionMode::Explicit, |this| visitor.visit_some(this))
}
}
OptionMode::StructField => {
// None struct values are ignored so if we're here the value must be Some.
self.with_option_mode(OptionMode::Explicit, |this| Ok(visitor.visit_some(this)?))
}
OptionMode::Explicit => {
expect!(self.events.next(), EventKind::StartDictionary);
let ret = match try_next!(self.events.next()) {
Event::String(ref s) if &s[..] == "None" => {
expect!(self.events.next(), EventKind::String);
visitor.visit_none::<Error>()?
}
Event::String(ref s) if &s[..] == "Some" => visitor.visit_some(&mut *self)?,
event => return Err(error::unexpected_event_type(EventKind::String, &event))?,
};
expect!(self.events.next(), EventKind::EndCollection);
Ok(ret)
}
}
}
fn deserialize_newtype_struct<V>(
self,
name: &'static str,
visitor: V,
) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
if name == VALUE_NEWTYPE_STRUCT_NAME {
self.enter_plist_value(|this| visitor.visit_newtype_struct(this))
} else {
visitor.visit_newtype_struct(self)
}
}
fn deserialize_struct<V>(
self,
_name: &'static str,
_fields: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
expect!(self.events.next(), EventKind::StartDictionary);
let ret = visitor.visit_map(MapAndSeqAccess::new(self, true, None))?;
expect!(self.events.next(), EventKind::EndCollection);
Ok(ret)
}
fn deserialize_enum<V>(
self,
name: &'static str,
variants: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
// `plist` since v1.1 serialises unit enum variants as plain strings.
if let Some(Ok(Event::String(s))) = self.events.peek() {
return s
.as_ref()
.into_deserializer()
.deserialize_enum(name, variants, visitor);
}
expect!(self.events.next(), EventKind::StartDictionary);
let ret = visitor.visit_enum(&mut *self)?;
expect!(self.events.next(), EventKind::EndCollection);
Ok(ret)
}
}
impl<'de, 'a, I> de::EnumAccess<'de> for &'a mut Deserializer<I>
where
I: IntoIterator<Item = Result<OwnedEvent, Error>>,
{
type Error = Error;
type Variant = Self;
fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self), Error>
where
V: de::DeserializeSeed<'de>,
{
Ok((seed.deserialize(&mut *self)?, self))
}
}
impl<'de, 'a, I> de::VariantAccess<'de> for &'a mut Deserializer<I>
where
I: IntoIterator<Item = Result<OwnedEvent, Error>>,
{
type Error = Error;
fn unit_variant(self) -> Result<(), Error> {
<() as de::Deserialize>::deserialize(self)
}
fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value, Error>
where
T: de::DeserializeSeed<'de>,
{
seed.deserialize(self)
}
fn tuple_variant<V>(self, len: usize, visitor: V) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
de::Deserializer::deserialize_tuple(self, len, visitor)
}
fn struct_variant<V>(
self,
fields: &'static [&'static str],
visitor: V,
) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
let name = "";
de::Deserializer::deserialize_struct(self, name, fields, visitor)
}
}
struct MapAndSeqAccess<'a, I>
where
I: 'a + IntoIterator<Item = Result<OwnedEvent, Error>>,
{
de: &'a mut Deserializer<I>,
is_struct: bool,
remaining: Option<usize>,
}
impl<'a, I> MapAndSeqAccess<'a, I>
where
I: 'a + IntoIterator<Item = Result<OwnedEvent, Error>>,
{
fn new(
de: &'a mut Deserializer<I>,
is_struct: bool,
len: Option<usize>,
) -> MapAndSeqAccess<'a, I> {
MapAndSeqAccess {
de,
is_struct,
remaining: len,
}
}
}
impl<'de, 'a, I> de::SeqAccess<'de> for MapAndSeqAccess<'a, I>
where
I: 'a + IntoIterator<Item = Result<OwnedEvent, Error>>,
{
type Error = Error;
fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Error>
where
T: de::DeserializeSeed<'de>,
{
if let Some(&Ok(Event::EndCollection)) = self.de.events.peek() {
return Ok(None);
}
self.remaining = self.remaining.map(|r| r.saturating_sub(1));
self.de
.with_option_mode(OptionMode::Explicit, |this| seed.deserialize(this))
.map(Some)
}
fn size_hint(&self) -> Option<usize> {
self.remaining
}
}
impl<'de, 'a, I> de::MapAccess<'de> for MapAndSeqAccess<'a, I>
where
I: 'a + IntoIterator<Item = Result<OwnedEvent, Error>>,
{
type Error = Error;
fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Error>
where
K: de::DeserializeSeed<'de>,
{
if let Some(&Ok(Event::EndCollection)) = self.de.events.peek() {
return Ok(None);
}
self.remaining = self.remaining.map(|r| r.saturating_sub(1));
self.de
.with_option_mode(OptionMode::Explicit, |this| seed.deserialize(this))
.map(Some)
}
fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Error>
where
V: de::DeserializeSeed<'de>,
{
let option_mode = if self.is_struct {
OptionMode::StructField
} else {
OptionMode::Explicit
};
self.de
.with_option_mode(option_mode, |this| Ok(seed.deserialize(this)?))
}
fn size_hint(&self) -> Option<usize> {
self.remaining
}
}
/// Deserializes an instance of type `T` from a byte slice.
pub fn from_bytes<T: de::DeserializeOwned>(bytes: &[u8]) -> Result<T, Error> {
let cursor = Cursor::new(bytes);
from_reader(cursor)
}
/// Deserializes an instance of type `T` from a plist file of any encoding.
pub fn from_file<P: AsRef<Path>, T: de::DeserializeOwned>(path: P) -> Result<T, Error> {
let file = File::open(path).map_err(error::from_io_without_position)?;
from_reader(BufReader::new(file))
}
/// Deserializes an instance of type `T` from a seekable byte stream containing a plist of any encoding.
pub fn from_reader<R: Read + Seek, T: de::DeserializeOwned>(reader: R) -> Result<T, Error> {
let reader = stream::Reader::new(reader);
let mut de = Deserializer::new(reader);
de::Deserialize::deserialize(&mut de)
}
/// Deserializes an instance of type `T` from a byte stream containing an XML encoded plist.
pub fn from_reader_xml<R: Read, T: de::DeserializeOwned>(reader: R) -> Result<T, Error> {
let reader = stream::XmlReader::new(reader);
let mut de = Deserializer::new(reader);
de::Deserialize::deserialize(&mut de)
}