1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154

// 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.

//! Types used in the pallet.

use crate::{Config, CreditOf, Event, Pallet};
use codec::{Decode, Encode, MaxEncodedLen};
use core::ops::BitOr;
use frame_support::traits::{Imbalance, LockIdentifier, OnUnbalanced, WithdrawReasons};
use scale_info::TypeInfo;
use sp_runtime::{RuntimeDebug, Saturating};

/// Simplified reasons for withdrawing balance.
#[derive(Encode, Decode, Clone, Copy, PartialEq, Eq, RuntimeDebug, MaxEncodedLen, TypeInfo)]
pub enum Reasons {
	/// Paying system transaction fees.
	Fee = 0,
	/// Any reason other than paying system transaction fees.
	Misc = 1,
	/// Any reason at all.
	All = 2,
}

impl From<WithdrawReasons> for Reasons {
	fn from(r: WithdrawReasons) -> Reasons {
		if r == WithdrawReasons::TRANSACTION_PAYMENT {
			Reasons::Fee
		} else if r.contains(WithdrawReasons::TRANSACTION_PAYMENT) {
			Reasons::All
		} else {
			Reasons::Misc
		}
	}
}

impl BitOr for Reasons {
	type Output = Reasons;
	fn bitor(self, other: Reasons) -> Reasons {
		if self == other {
			return self
		}
		Reasons::All
	}
}

/// A single lock on a balance. There can be many of these on an account and they "overlap", so the
/// same balance is frozen by multiple locks.
#[derive(Encode, Decode, Clone, PartialEq, Eq, RuntimeDebug, MaxEncodedLen, TypeInfo)]
pub struct BalanceLock<Balance> {
	/// An identifier for this lock. Only one lock may be in existence for each identifier.
	pub id: LockIdentifier,
	/// The amount which the free balance may not drop below when this lock is in effect.
	pub amount: Balance,
	/// If true, then the lock remains in effect even for payment of transaction fees.
	pub reasons: Reasons,
}

/// Store named reserved balance.
#[derive(Encode, Decode, Clone, PartialEq, Eq, RuntimeDebug, MaxEncodedLen, TypeInfo)]
pub struct ReserveData<ReserveIdentifier, Balance> {
	/// The identifier for the named reserve.
	pub id: ReserveIdentifier,
	/// The amount of the named reserve.
	pub amount: Balance,
}

/// An identifier and balance.
#[derive(Encode, Decode, Clone, PartialEq, Eq, RuntimeDebug, MaxEncodedLen, TypeInfo)]
pub struct IdAmount<Id, Balance> {
	/// An identifier for this item.
	pub id: Id,
	/// Some amount for this item.
	pub amount: Balance,
}

/// All balance information for an account.
#[derive(Encode, Decode, Clone, PartialEq, Eq, Default, RuntimeDebug, MaxEncodedLen, TypeInfo)]
pub struct AccountData<Balance> {
	/// Non-reserved part of the balance which the account holder may be able to control.
	///
	/// This is the only balance that matters in terms of most operations on tokens.
	pub free: Balance,
	/// Balance which is has active holds on it and may not be used at all.
	///
	/// This is the sum of all individual holds together with any sums still under the (deprecated)
	/// reserves API.
	pub reserved: Balance,
	/// The amount that `free + reserved` may not drop below when reducing the balance, except for
	/// actions where the account owner cannot reasonably benefit from the balance reduction, such
	/// as slashing.
	pub frozen: Balance,
	/// Extra information about this account. The MSB is a flag indicating whether the new ref-
	/// counting logic is in place for this account.
	pub flags: ExtraFlags,
}

const IS_NEW_LOGIC: u128 = 0x80000000_00000000_00000000_00000000u128;

#[derive(Encode, Decode, Clone, PartialEq, Eq, RuntimeDebug, MaxEncodedLen, TypeInfo)]
pub struct ExtraFlags(u128);
impl Default for ExtraFlags {
	fn default() -> Self {
		Self(IS_NEW_LOGIC)
	}
}
impl ExtraFlags {
	pub fn old_logic() -> Self {
		Self(0)
	}
	pub fn set_new_logic(&mut self) {
		self.0 = self.0 | IS_NEW_LOGIC
	}
	pub fn is_new_logic(&self) -> bool {
		(self.0 & IS_NEW_LOGIC) == IS_NEW_LOGIC
	}
}

impl<Balance: Saturating + Copy + Ord> AccountData<Balance> {
	pub fn usable(&self) -> Balance {
		self.free.saturating_sub(self.frozen)
	}

	/// The total balance in this account including any that is reserved and ignoring any frozen.
	pub fn total(&self) -> Balance {
		self.free.saturating_add(self.reserved)
	}
}

pub struct DustCleaner<T: Config<I>, I: 'static = ()>(
	pub(crate) Option<(T::AccountId, CreditOf<T, I>)>,
);

impl<T: Config<I>, I: 'static> Drop for DustCleaner<T, I> {
	fn drop(&mut self) {
		if let Some((who, dust)) = self.0.take() {
			Pallet::<T, I>::deposit_event(Event::DustLost { account: who, amount: dust.peek() });
			T::DustRemoval::on_unbalanced(dust);
		}
	}
}