1  // Copyright (c) 2019-2025 Alpha-Delta Network Inc.
 2  // This file is part of the alphavm library.
 3  
 4  // Licensed under the Apache License, Version 2.0 (the "License");
 5  // you may not use this file except in compliance with the License.
 6  // You may obtain a copy of the License at:
 7  
 8  // http://www.apache.org/licenses/LICENSE-2.0
 9  
10  // Unless required by applicable law or agreed to in writing, software
11  // distributed under the License is distributed on an "AS IS" BASIS,
12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  // See the License for the specific language governing permissions and
14  // limitations under the License.
15  
16  use super::*;
17  
18  impl<N: Network> Visibility for Plaintext<N> {
19      type Boolean = Boolean<N>;
20  
21      /// Returns the number of field elements to encode `self`.
22      fn size_in_fields(&self) -> Result<u16> {
23          // Compute the number of bits.
24          let num_bits = self.to_bits_le().len() + 1; // 1 extra bit for the terminus indicator.
25          // Compute the ceiling division of the number of bits by the number of bits in a field element.
26          let num_fields = num_bits.div_ceil(Field::<N>::size_in_data_bits());
27          // Ensure the number of field elements does not exceed the maximum allowed size.
28          match num_fields <= N::MAX_DATA_SIZE_IN_FIELDS as usize {
29              // Return the number of field elements.
30              true => Ok(u16::try_from(num_fields).or_halt_with::<N>("Plaintext exceeds u16::MAX field elements.")),
31              false => bail!("Plaintext cannot exceed {} field elements.", N::MAX_DATA_SIZE_IN_FIELDS),
32          }
33      }
34  }