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

// 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.

//! The conviction datatype.

use crate::types::Delegations;
use codec::{Decode, Encode, MaxEncodedLen};
use scale_info::TypeInfo;
use sp_runtime::{
	traits::{Bounded, CheckedDiv, CheckedMul, Zero},
	RuntimeDebug,
};
use sp_std::{prelude::*, result::Result};

/// A value denoting the strength of conviction of a vote.
#[derive(
	Encode,
	MaxEncodedLen,
	Decode,
	Copy,
	Clone,
	Eq,
	PartialEq,
	Ord,
	PartialOrd,
	RuntimeDebug,
	TypeInfo,
)]
pub enum Conviction {
	/// 0.1x votes, unlocked.
	None,
	/// 1x votes, locked for an enactment period following a successful vote.
	Locked1x,
	/// 2x votes, locked for 2x enactment periods following a successful vote.
	Locked2x,
	/// 3x votes, locked for 4x...
	Locked3x,
	/// 4x votes, locked for 8x...
	Locked4x,
	/// 5x votes, locked for 16x...
	Locked5x,
	/// 6x votes, locked for 32x...
	Locked6x,
}

impl Default for Conviction {
	fn default() -> Self {
		Conviction::None
	}
}

impl From<Conviction> for u8 {
	fn from(c: Conviction) -> u8 {
		match c {
			Conviction::None => 0,
			Conviction::Locked1x => 1,
			Conviction::Locked2x => 2,
			Conviction::Locked3x => 3,
			Conviction::Locked4x => 4,
			Conviction::Locked5x => 5,
			Conviction::Locked6x => 6,
		}
	}
}

impl TryFrom<u8> for Conviction {
	type Error = ();
	fn try_from(i: u8) -> Result<Conviction, ()> {
		Ok(match i {
			0 => Conviction::None,
			1 => Conviction::Locked1x,
			2 => Conviction::Locked2x,
			3 => Conviction::Locked3x,
			4 => Conviction::Locked4x,
			5 => Conviction::Locked5x,
			6 => Conviction::Locked6x,
			_ => return Err(()),
		})
	}
}

impl Conviction {
	/// The amount of time (in number of periods) that our conviction implies a successful voter's
	/// balance should be locked for.
	pub fn lock_periods(self) -> u32 {
		match self {
			Conviction::None => 0,
			Conviction::Locked1x => 1,
			Conviction::Locked2x => 2,
			Conviction::Locked3x => 4,
			Conviction::Locked4x => 8,
			Conviction::Locked5x => 16,
			Conviction::Locked6x => 32,
		}
	}

	/// The votes of a voter of the given `balance` with our conviction.
	pub fn votes<B: From<u8> + Zero + Copy + CheckedMul + CheckedDiv + Bounded>(
		self,
		capital: B,
	) -> Delegations<B> {
		let votes = match self {
			Conviction::None => capital.checked_div(&10u8.into()).unwrap_or_else(Zero::zero),
			x => capital.checked_mul(&u8::from(x).into()).unwrap_or_else(B::max_value),
		};
		Delegations { votes, capital }
	}
}

impl Bounded for Conviction {
	fn min_value() -> Self {
		Conviction::None
	}
	fn max_value() -> Self {
		Conviction::Locked6x
	}
}