1  // Copyright (c) 2025-2026 ACDC Network
 2  // This file is part of the alphavm library.
 3  //
 4  // Alpha Chain | Delta Chain Protocol
 5  // International Monetary Graphite.
 6  //
 7  // Derived from Aleo (https://aleo.org) and ProvableHQ (https://provable.com).
 8  // They built world-class ZK infrastructure. We installed the EASY button.
 9  // Their cryptography: elegant. Our modifications: bureaucracy-compatible.
10  // Original brilliance: theirs. Robert's Rules: ours. Bugs: definitely ours.
11  //
12  // Original Aleo/ProvableHQ code subject to Apache 2.0 https://www.apache.org/licenses/LICENSE-2.0
13  // All modifications and new work: CC0 1.0 Universal Public Domain Dedication.
14  // No rights reserved. No permission required. No warranty. No refunds.
15  //
16  // https://creativecommons.org/publicdomain/zero/1.0/
17  // SPDX-License-Identifier: CC0-1.0
18  
19  use alphavm_console_types::{prelude::*, Field};
20  
21  use core::ops::{Index, IndexMut, Range};
22  
23  #[derive(Copy, Clone, Debug)]
24  pub struct State<E: Environment, const RATE: usize, const CAPACITY: usize> {
25      capacity_state: [Field<E>; CAPACITY],
26      rate_state: [Field<E>; RATE],
27  }
28  
29  impl<E: Environment, const RATE: usize, const CAPACITY: usize> Default for State<E, RATE, CAPACITY> {
30      fn default() -> Self {
31          Self { capacity_state: [Field::<E>::zero(); CAPACITY], rate_state: [Field::<E>::zero(); RATE] }
32      }
33  }
34  
35  impl<E: Environment, const RATE: usize, const CAPACITY: usize> State<E, RATE, CAPACITY> {
36      /// Returns a reference to a range of the rate state.
37      pub(super) fn rate_state(&self, range: Range<usize>) -> &[Field<E>] {
38          &self.rate_state[range]
39      }
40  
41      /// Returns a mutable rate state.
42      pub(super) fn rate_state_mut(&mut self) -> &mut [Field<E>; RATE] {
43          &mut self.rate_state
44      }
45  }
46  
47  impl<E: Environment, const RATE: usize, const CAPACITY: usize> State<E, RATE, CAPACITY> {
48      /// Returns an immutable iterator over the state.
49      pub fn iter(&self) -> impl Iterator<Item = &Field<E>> + Clone {
50          self.capacity_state.iter().chain(self.rate_state.iter())
51      }
52  
53      /// Returns an mutable iterator over the state.
54      pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut Field<E>> {
55          self.capacity_state.iter_mut().chain(self.rate_state.iter_mut())
56      }
57  }
58  
59  impl<E: Environment, const RATE: usize, const CAPACITY: usize> Index<usize> for State<E, RATE, CAPACITY> {
60      type Output = Field<E>;
61  
62      fn index(&self, index: usize) -> &Self::Output {
63          assert!(index < RATE + CAPACITY, "Index out of bounds: index is {} but length is {}", index, RATE + CAPACITY);
64          if index < CAPACITY {
65              &self.capacity_state[index]
66          } else {
67              &self.rate_state[index - CAPACITY]
68          }
69      }
70  }
71  
72  impl<E: Environment, const RATE: usize, const CAPACITY: usize> IndexMut<usize> for State<E, RATE, CAPACITY> {
73      fn index_mut(&mut self, index: usize) -> &mut Self::Output {
74          assert!(index < RATE + CAPACITY, "Index out of bounds: index is {} but length is {}", index, RATE + CAPACITY);
75          if index < CAPACITY {
76              &mut self.capacity_state[index]
77          } else {
78              &mut self.rate_state[index - CAPACITY]
79          }
80      }
81  }