//! Generate the internal `bitflags`-facing flags type.
//!
//! The code generated here is owned by `bitflags`, but still part of its public API.
//! Changes to the types generated here need to be considered like any other public API change.

/// Declare the `bitflags`-facing bitflags struct.
///
/// This type is part of the `bitflags` crate's public API, but not part of the user's.
#[macro_export]
#[doc(hidden)]
macro_rules! __declare_internal_bitflags {
 (
 $vis:vis struct $InternalBitFlags:ident: $T:ty
 ) => {
 // NOTE: The ABI of this type is _guaranteed_ to be the same as `T`
 // This is relied on by some external libraries like `bytemuck` to make
 // its `unsafe` trait impls sound.
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[repr(transparent)]
 $vis struct $InternalBitFlags($T);
 };
}

/// Implement functions on the private (bitflags-facing) bitflags type.
///
/// Methods and trait implementations can be freely added here without breaking end-users.
/// If we want to expose new functionality to `#[derive]`, this is the place to do it.
#[macro_export]
#[doc(hidden)]
macro_rules! __impl_internal_bitflags {
 (
 $InternalBitFlags:ident: $T:ty, $PublicBitFlags:ident {
 $(
 $(#[$inner:ident $($args:tt)*])*
 const $Flag:tt = $value:expr;
 )*
 }
 ) => {
 // NOTE: This impl is also used to prevent using bits types from non-primitive types
 // in the `bitflags` macro. If this approach is changed, this guard will need to be
 // retained somehow
 impl $crate::__private::PublicFlags for $PublicBitFlags {
 type Primitive = $T;
 type Internal = $InternalBitFlags;
 }

 impl $crate::__private::core::default::Default for $InternalBitFlags {
 #[inline]
 fn default() -> Self {
 $InternalBitFlags::empty()
 }
 }

 impl $crate::__private::core::fmt::Debug for $InternalBitFlags {
 fn fmt(&self, f: &mut $crate::__private::core::fmt::Formatter<'_>) -> $crate::__private::core::fmt::Result {
 if self.is_empty() {
 // If no flags are set then write an empty hex flag to avoid
 // writing an empty string. In some contexts, like serialization,
 // an empty string is preferable, but it may be unexpected in
 // others for a format not to produce any output.
 //
 // We can remove this `0x0` and remain compatible with `FromStr`,
 // because an empty string will still parse to an empty set of flags,
 // just like `0x0` does.
 $crate::__private::core::write!(f, "{:#x}", <$T as $crate::Bits>::EMPTY)
 } else {
 $crate::__private::core::fmt::Display::fmt(self, f)
 }
 }
 }

 impl $crate::__private::core::fmt::Display for $InternalBitFlags {
 fn fmt(&self, f: &mut $crate::__private::core::fmt::Formatter<'_>) -> $crate::__private::core::fmt::Result {
 $crate::parser::to_writer(&$PublicBitFlags(*self), f)
 }
 }

 impl $crate::__private::core::str::FromStr for $InternalBitFlags {
 type Err = $crate::parser::ParseError;

 fn from_str(s: &str) -> $crate::__private::core::result::Result<Self, Self::Err> {
 $crate::parser::from_str::<$PublicBitFlags>(s).map(|flags| flags.0)
 }
 }

 impl $crate::__private::core::convert::AsRef<$T> for $InternalBitFlags {
 fn as_ref(&self) -> &$T {
 &self.0
 }
 }

 impl $crate::__private::core::convert::From<$T> for $InternalBitFlags {
 fn from(bits: $T) -> Self {
 Self::from_bits_retain(bits)
 }
 }

 // The internal flags type offers a similar API to the public one

 $crate::__impl_public_bitflags! {
 $InternalBitFlags: $T, $PublicBitFlags {
 $(
 $(#[$inner $($args)*])*
 const $Flag = $value;
 )*
 }
 }

 $crate::__impl_public_bitflags_ops! {
 $InternalBitFlags
 }

 $crate::__impl_public_bitflags_iter! {
 $InternalBitFlags: $T, $PublicBitFlags
 }

 impl $InternalBitFlags {
 /// Returns a mutable reference to the raw value of the flags currently stored.
 #[inline]
 pub fn bits_mut(&mut self) -> &mut $T {
 &mut self.0
 }
 }
 };
}