// This file is part of Substrate.

// Copyright (C) 2017-2022 Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Shareable Substrate types.

#![warn(missing_docs)]
#![cfg_attr(not(feature = "std"), no_std)]

/// Initialize a key-value collection from array.
///
/// Creates a vector of given pairs and calls `collect` on the iterator from it.
/// Can be used to create a `HashMap`.
#[macro_export]
macro_rules! map {
	($( $name:expr => $value:expr ),* $(,)? ) => (
		vec![ $( ( $name, $value ) ),* ].into_iter().collect()
	);
}

#[doc(hidden)]
pub use codec::{Decode, Encode, MaxEncodedLen};
use scale_info::TypeInfo;
#[cfg(feature = "std")]
pub use serde;
#[cfg(feature = "std")]
use serde::{Deserialize, Serialize};
use sp_runtime_interface::pass_by::{PassByEnum, PassByInner};
use sp_std::{ops::Deref, prelude::*};

pub use sp_debug_derive::RuntimeDebug;

#[cfg(feature = "std")]
pub use impl_serde::serialize as bytes;

#[cfg(feature = "full_crypto")]
pub mod hashing;

#[cfg(feature = "full_crypto")]
pub use hashing::{blake2_128, blake2_256, keccak_256, twox_128, twox_256, twox_64};
pub mod bounded;
pub mod crypto;
pub mod hexdisplay;

pub mod defer;
pub mod ecdsa;
pub mod ed25519;
pub mod hash;
#[cfg(feature = "std")]
mod hasher;
pub mod offchain;
pub mod sr25519;
pub mod testing;
#[cfg(feature = "std")]
pub mod traits;
pub mod uint;

pub use self::{
	hash::{convert_hash, H160, H256, H512},
	uint::{U256, U512},
};
#[cfg(feature = "full_crypto")]
pub use crypto::{ByteArray, DeriveJunction, Pair, Public};

#[cfg(feature = "std")]
pub use self::hasher::blake2::Blake2Hasher;
#[cfg(feature = "std")]
pub use self::hasher::keccak::KeccakHasher;
pub use hash_db::Hasher;

pub use sp_storage as storage;

#[doc(hidden)]
pub use sp_std;

/// Context for executing a call into the runtime.
pub enum ExecutionContext {
	/// Context used for general block import (including locally authored blocks).
	Importing,
	/// Context used for importing blocks as part of an initial sync of the blockchain.
	///
	/// We distinguish between major sync and import so that validators who are running
	/// their initial sync (or catching up after some time offline) can use the faster
	/// native runtime (since we can reasonably assume the network as a whole has already
	/// come to a broad consensus on the block and it probably hasn't been crafted
	/// specifically to attack this node), but when importing blocks at the head of the
	/// chain in normal operation they can use the safer Wasm version.
	Syncing,
	/// Context used for block construction.
	BlockConstruction,
	/// Context used for offchain calls.
	///
	/// This allows passing offchain extension and customizing available capabilities.
	OffchainCall(Option<(Box<dyn offchain::Externalities>, offchain::Capabilities)>),
}

impl ExecutionContext {
	/// Returns the capabilities of particular context.
	pub fn capabilities(&self) -> offchain::Capabilities {
		use ExecutionContext::*;

		match self {
			Importing | Syncing | BlockConstruction => offchain::Capabilities::empty(),
			// Enable keystore, transaction pool and Offchain DB reads by default for offchain
			// calls.
			OffchainCall(None) =>
				offchain::Capabilities::KEYSTORE |
					offchain::Capabilities::OFFCHAIN_DB_READ |
					offchain::Capabilities::TRANSACTION_POOL,
			OffchainCall(Some((_, capabilities))) => *capabilities,
		}
	}
}

/// Hex-serialized shim for `Vec<u8>`.
#[derive(PartialEq, Eq, Clone, RuntimeDebug)]
#[cfg_attr(feature = "std", derive(Serialize, Deserialize, Hash, PartialOrd, Ord))]
pub struct Bytes(#[cfg_attr(feature = "std", serde(with = "bytes"))] pub Vec<u8>);

impl From<Vec<u8>> for Bytes {
	fn from(s: Vec<u8>) -> Self {
		Bytes(s)
	}
}

impl From<OpaqueMetadata> for Bytes {
	fn from(s: OpaqueMetadata) -> Self {
		Bytes(s.0)
	}
}

impl Deref for Bytes {
	type Target = [u8];
	fn deref(&self) -> &[u8] {
		&self.0[..]
	}
}

impl codec::WrapperTypeEncode for Bytes {}

impl codec::WrapperTypeDecode for Bytes {
	type Wrapped = Vec<u8>;
}

#[cfg(feature = "std")]
impl sp_std::str::FromStr for Bytes {
	type Err = bytes::FromHexError;

	fn from_str(s: &str) -> Result<Self, Self::Err> {
		bytes::from_hex(s).map(Bytes)
	}
}

/// Stores the encoded `RuntimeMetadata` for the native side as opaque type.
#[derive(Encode, Decode, PartialEq)]
pub struct OpaqueMetadata(Vec<u8>);

impl OpaqueMetadata {
	/// Creates a new instance with the given metadata blob.
	pub fn new(metadata: Vec<u8>) -> Self {
		OpaqueMetadata(metadata)
	}
}

impl sp_std::ops::Deref for OpaqueMetadata {
	type Target = Vec<u8>;

	fn deref(&self) -> &Self::Target {
		&self.0
	}
}

/// Simple blob to hold a `PeerId` without committing to its format.
#[derive(
	Default,
	Clone,
	Eq,
	PartialEq,
	Ord,
	PartialOrd,
	Encode,
	Decode,
	RuntimeDebug,
	PassByInner,
	TypeInfo,
)]
#[cfg_attr(feature = "std", derive(Serialize, Deserialize))]
pub struct OpaquePeerId(pub Vec<u8>);

impl OpaquePeerId {
	/// Create new `OpaquePeerId`
	pub fn new(vec: Vec<u8>) -> Self {
		OpaquePeerId(vec)
	}
}

/// Provide a simple 4 byte identifier for a type.
pub trait TypeId {
	/// Simple 4 byte identifier.
	const TYPE_ID: [u8; 4];
}

/// A log level matching the one from `log` crate.
///
/// Used internally by `sp_io::logging::log` method.
#[derive(Encode, Decode, PassByEnum, Copy, Clone)]
pub enum LogLevel {
	/// `Error` log level.
	Error = 1_isize,
	/// `Warn` log level.
	Warn = 2_isize,
	/// `Info` log level.
	Info = 3_isize,
	/// `Debug` log level.
	Debug = 4_isize,
	/// `Trace` log level.
	Trace = 5_isize,
}

impl From<u32> for LogLevel {
	fn from(val: u32) -> Self {
		match val {
			x if x == LogLevel::Warn as u32 => LogLevel::Warn,
			x if x == LogLevel::Info as u32 => LogLevel::Info,
			x if x == LogLevel::Debug as u32 => LogLevel::Debug,
			x if x == LogLevel::Trace as u32 => LogLevel::Trace,
			_ => LogLevel::Error,
		}
	}
}

impl From<log::Level> for LogLevel {
	fn from(l: log::Level) -> Self {
		use log::Level::*;
		match l {
			Error => Self::Error,
			Warn => Self::Warn,
			Info => Self::Info,
			Debug => Self::Debug,
			Trace => Self::Trace,
		}
	}
}

impl From<LogLevel> for log::Level {
	fn from(l: LogLevel) -> Self {
		use self::LogLevel::*;
		match l {
			Error => Self::Error,
			Warn => Self::Warn,
			Info => Self::Info,
			Debug => Self::Debug,
			Trace => Self::Trace,
		}
	}
}

/// Log level filter that expresses which log levels should be filtered.
///
/// This enum matches the [`log::LevelFilter`] enum.
#[derive(Encode, Decode, PassByEnum, Copy, Clone)]
pub enum LogLevelFilter {
	/// `Off` log level filter.
	Off = 0_isize,
	/// `Error` log level filter.
	Error = 1_isize,
	/// `Warn` log level filter.
	Warn = 2_isize,
	/// `Info` log level filter.
	Info = 3_isize,
	/// `Debug` log level filter.
	Debug = 4_isize,
	/// `Trace` log level filter.
	Trace = 5_isize,
}

impl From<LogLevelFilter> for log::LevelFilter {
	fn from(l: LogLevelFilter) -> Self {
		use self::LogLevelFilter::*;
		match l {
			Off => Self::Off,
			Error => Self::Error,
			Warn => Self::Warn,
			Info => Self::Info,
			Debug => Self::Debug,
			Trace => Self::Trace,
		}
	}
}

impl From<log::LevelFilter> for LogLevelFilter {
	fn from(l: log::LevelFilter) -> Self {
		use log::LevelFilter::*;
		match l {
			Off => Self::Off,
			Error => Self::Error,
			Warn => Self::Warn,
			Info => Self::Info,
			Debug => Self::Debug,
			Trace => Self::Trace,
		}
	}
}

/// Encodes the given value into a buffer and returns the pointer and the length as a single `u64`.
///
/// When Substrate calls into Wasm it expects a fixed signature for functions exported
/// from the Wasm blob. The return value of this signature is always a `u64`.
/// This `u64` stores the pointer to the encoded return value and the length of this encoded value.
/// The low `32bits` are reserved for the pointer, followed by `32bit` for the length.
#[cfg(not(feature = "std"))]
pub fn to_substrate_wasm_fn_return_value(value: &impl Encode) -> u64 {
	let encoded = value.encode();

	let ptr = encoded.as_ptr() as u64;
	let length = encoded.len() as u64;
	let res = ptr | (length << 32);

	// Leak the output vector to avoid it being freed.
	// This is fine in a WASM context since the heap
	// will be discarded after the call.
	sp_std::mem::forget(encoded);

	res
}

/// The void type - it cannot exist.
// Oh rust, you crack me up...
#[derive(Clone, Decode, Encode, Eq, PartialEq, RuntimeDebug, TypeInfo, MaxEncodedLen)]
pub enum Void {}

/// Macro for creating `Maybe*` marker traits.
///
/// Such a maybe-marker trait requires the given bound when `feature = std` and doesn't require
/// the bound on `no_std`. This is useful for situations where you require that a type implements
/// a certain trait with `feature = std`, but not on `no_std`.
///
/// # Example
///
/// ```
/// sp_core::impl_maybe_marker! {
///     /// A marker for a type that implements `Debug` when `feature = std`.
///     trait MaybeDebug: std::fmt::Debug;
///     /// A marker for a type that implements `Debug + Display` when `feature = std`.
///     trait MaybeDebugDisplay: std::fmt::Debug, std::fmt::Display;
/// }
/// ```
#[macro_export]
macro_rules! impl_maybe_marker {
	(
		$(
			$(#[$doc:meta] )+
			trait $trait_name:ident: $( $trait_bound:path ),+;
		)+
	) => {
		$(
			$(#[$doc])+
			#[cfg(feature = "std")]
			pub trait $trait_name: $( $trait_bound + )+ {}
			#[cfg(feature = "std")]
			impl<T: $( $trait_bound + )+> $trait_name for T {}

			$(#[$doc])+
			#[cfg(not(feature = "std"))]
			pub trait $trait_name {}
			#[cfg(not(feature = "std"))]
			impl<T> $trait_name for T {}
		)+
	}
}

/// The maximum number of bytes that can be allocated at one time.
// The maximum possible allocation size was chosen rather arbitrary, 32 MiB should be enough for
// everybody.
pub const MAX_POSSIBLE_ALLOCATION: u32 = 33554432; // 2^25 bytes, 32 MiB

/// A trait for querying a single value from a type defined in the trait.
///
/// It is not required that the value is constant.
pub trait TypedGet {
	/// The type which is returned.
	type Type;
	/// Return the current value.
	fn get() -> Self::Type;
}

/// A trait for querying a single value from a type.
///
/// It is not required that the value is constant.
pub trait Get<T> {
	/// Return the current value.
	fn get() -> T;
}

impl<T: Default> Get<T> for () {
	fn get() -> T {
		T::default()
	}
}

/// Implement Get by returning Default for any type that implements Default.
pub struct GetDefault;
impl<T: Default> Get<T> for GetDefault {
	fn get() -> T {
		T::default()
	}
}

macro_rules! impl_const_get {
	($name:ident, $t:ty) => {
		#[doc = "Const getter for a basic type."]
		#[derive($crate::RuntimeDebug)]
		pub struct $name<const T: $t>;
		impl<const T: $t> Get<$t> for $name<T> {
			fn get() -> $t {
				T
			}
		}
		impl<const T: $t> Get<Option<$t>> for $name<T> {
			fn get() -> Option<$t> {
				Some(T)
			}
		}
		impl<const T: $t> TypedGet for $name<T> {
			type Type = $t;
			fn get() -> $t {
				T
			}
		}
	};
}

impl_const_get!(ConstBool, bool);
impl_const_get!(ConstU8, u8);
impl_const_get!(ConstU16, u16);
impl_const_get!(ConstU32, u32);
impl_const_get!(ConstU64, u64);
impl_const_get!(ConstU128, u128);
impl_const_get!(ConstI8, i8);
impl_const_get!(ConstI16, i16);
impl_const_get!(ConstI32, i32);
impl_const_get!(ConstI64, i64);
impl_const_get!(ConstI128, i128);

/// Try and collect into a collection `C`.
pub trait TryCollect<C> {
	/// The error type that gets returned when a collection can't be made from `self`.
	type Error;
	/// Consume self and try to collect the results into `C`.
	///
	/// This is useful in preventing the undesirable `.collect().try_into()` call chain on
	/// collections that need to be converted into a bounded type (e.g. `BoundedVec`).
	fn try_collect(self) -> Result<C, Self::Error>;
}

/// Create new implementations of the [`Get`](crate::Get) trait.
///
/// The so-called parameter type can be created in four different ways:
///
/// - Using `const` to create a parameter type that provides a `const` getter. It is required that
///   the `value` is const.
///
/// - Declare the parameter type without `const` to have more freedom when creating the value.
///
/// NOTE: A more substantial version of this macro is available in `frame_support` crate which
/// allows mutable and persistant variants.
///
/// # Examples
///
/// ```
/// # use sp_core::Get;
/// # use sp_core::parameter_types;
/// // This function cannot be used in a const context.
/// fn non_const_expression() -> u64 { 99 }
///
/// const FIXED_VALUE: u64 = 10;
/// parameter_types! {
///    pub const Argument: u64 = 42 + FIXED_VALUE;
///    /// Visibility of the type is optional
///    OtherArgument: u64 = non_const_expression();
/// }
///
/// trait Config {
///    type Parameter: Get<u64>;
///    type OtherParameter: Get<u64>;
/// }
///
/// struct Runtime;
/// impl Config for Runtime {
///    type Parameter = Argument;
///    type OtherParameter = OtherArgument;
/// }
/// ```
///
/// # Invalid example:
///
/// ```compile_fail
/// # use sp_core::Get;
/// # use sp_core::parameter_types;
/// // This function cannot be used in a const context.
/// fn non_const_expression() -> u64 { 99 }
///
/// parameter_types! {
///    pub const Argument: u64 = non_const_expression();
/// }
/// ```
#[macro_export]
macro_rules! parameter_types {
	(
		$( #[ $attr:meta ] )*
		$vis:vis const $name:ident: $type:ty = $value:expr;
		$( $rest:tt )*
	) => (
		$( #[ $attr ] )*
		$vis struct $name;
		$crate::parameter_types!(@IMPL_CONST $name , $type , $value);
		$crate::parameter_types!( $( $rest )* );
	);
	(
		$( #[ $attr:meta ] )*
		$vis:vis $name:ident: $type:ty = $value:expr;
		$( $rest:tt )*
	) => (
		$( #[ $attr ] )*
		$vis struct $name;
		$crate::parameter_types!(@IMPL $name, $type, $value);
		$crate::parameter_types!( $( $rest )* );
	);
	() => ();
	(@IMPL_CONST $name:ident, $type:ty, $value:expr) => {
		impl $name {
			/// Returns the value of this parameter type.
			pub const fn get() -> $type {
				$value
			}
		}

		impl<I: From<$type>> $crate::Get<I> for $name {
			fn get() -> I {
				I::from(Self::get())
			}
		}

		impl $crate::TypedGet for $name {
			type Type = $type;
			fn get() -> $type {
				Self::get()
			}
		}
	};
	(@IMPL $name:ident, $type:ty, $value:expr) => {
		impl $name {
			/// Returns the value of this parameter type.
			pub fn get() -> $type {
				$value
			}
		}

		impl<I: From<$type>> $crate::Get<I> for $name {
			fn get() -> I {
				I::from(Self::get())
			}
		}

		impl $crate::TypedGet for $name {
			type Type = $type;
			fn get() -> $type {
				Self::get()
			}
		}
	};
}

/// Build a bounded vec from the given literals.
///
/// The type of the outcome must be known.
///
/// Will not handle any errors and just panic if the given literals cannot fit in the corresponding
/// bounded vec type. Thus, this is only suitable for testing and non-consensus code.
#[macro_export]
#[cfg(feature = "std")]
macro_rules! bounded_vec {
	($ ($values:expr),* $(,)?) => {
		{
			$crate::sp_std::vec![$($values),*].try_into().unwrap()
		}
	};
	( $value:expr ; $repetition:expr ) => {
		{
			$crate::sp_std::vec![$value ; $repetition].try_into().unwrap()
		}
	}
}

/// Build a bounded btree-map from the given literals.
///
/// The type of the outcome must be known.
///
/// Will not handle any errors and just panic if the given literals cannot fit in the corresponding
/// bounded vec type. Thus, this is only suitable for testing and non-consensus code.
#[macro_export]
#[cfg(feature = "std")]
macro_rules! bounded_btree_map {
	($ ( $key:expr => $value:expr ),* $(,)?) => {
		{
			$crate::TryCollect::<$crate::bounded::BoundedBTreeMap<_, _, _>>::try_collect(
				$crate::sp_std::vec![$(($key, $value)),*].into_iter()
			).unwrap()
		}
	};
}

/// Generates a macro for checking if a certain feature is enabled.
///
/// These feature checking macros can be used to conditionally enable/disable code in a dependent
/// crate based on a feature in the crate where the macro is called.
#[macro_export]
// We need to skip formatting this macro because of this bug:
// https://github.com/rust-lang/rustfmt/issues/5283
#[rustfmt::skip]
macro_rules! generate_feature_enabled_macro {
	( $macro_name:ident, $feature_name:meta, $d:tt ) => {
		/// Enable/disable the given code depending on
		#[doc = concat!("`", stringify!($feature_name), "`")]
		/// being enabled for the crate or not.
		///
		/// # Example
		///
		/// ```nocompile
		/// // Will add the code depending on the feature being enabled or not.
		#[doc = concat!(stringify!($macro_name), "!( println!(\"Hello\") )")]
		/// ```
		#[cfg($feature_name)]
		#[macro_export]
		macro_rules! $macro_name {
			( $d ( $d input:tt )* ) => {
				$d ( $d input )*
			}
		}

		/// Enable/disable the given code depending on
		#[doc = concat!("`", stringify!($feature_name), "`")]
		/// being enabled for the crate or not.
		///
		/// # Example
		///
		/// ```nocompile
		/// // Will add the code depending on the feature being enabled or not.
		#[doc = concat!(stringify!($macro_name), "!( println!(\"Hello\") )")]
		/// ```
		#[cfg(not($feature_name))]
		#[macro_export]
		macro_rules! $macro_name {
			( $d ( $d input:tt )* ) => {};
		}
	};
}